@article {pmid40559638,
year = {2025},
author = {Lincoln, OJ and Houghton, JDR and Zakariya, M and Lauritano, C and D'Ambra, I},
title = {Chemical Defenses in Medusozoa.},
journal = {Marine drugs},
volume = {23},
number = {6},
pages = {},
doi = {10.3390/md23060229},
pmid = {40559638},
issn = {1660-3397},
mesh = {Animals ; *Cnidaria/physiology/chemistry ; Antioxidants/pharmacology ; Symbiosis ; Anti-Infective Agents/pharmacology ; Antimicrobial Peptides/pharmacology ; Humans ; },
abstract = {Cnidarian defensive strategies are commonly associated with the toxins they synthesize. Because toxins have negative, sometimes lethal, effects on humans, research has focused on them for medical and biotechnological applications. However, Cnidaria possess a variety of defensive systems complementing toxins. In recent decades, ecological and biotechnological studies have shed light on these systems, particularly in Anthozoa, while the knowledge of defensive systems different from toxins has remained limited in Medusozoa (Cubozoa, Hydrozoa, Scyphozoa and Staurozoa). In this review, we collected the scattered information available in the literature and organized it into four main topics: UV-light protection compounds, antioxidants, antimicrobial peptides, and endosymbionts. Within the topics, we found the largest amount of data refers to antimicrobial activities, which suggests this line of research as a potential exploitation of this group of organisms often appearing in large aggregates. We also found that some Medusozoa have been studied in detail as model organisms, although the close phylogenetic relationship among classes suggests that some defensive strategies may be common to other members of different classes. Indeed, an integrated understanding of defensive systems has the potential to inform not only ecological and evolutionary frameworks, but also biotechnological applications-from the identification of novel antioxidants or antimicrobial agents to the valorization of Medusozoan biomass.},
}

Animals
*Cnidaria/physiology/chemistry
Antioxidants/pharmacology
Symbiosis
Anti-Infective Agents/pharmacology
Antimicrobial Peptides/pharmacology
Humans

@article {pmid40558985,
year = {2025},
author = {Hance, T and Hamidovic, A and Suraporn, S},
title = {Insight into the Microbiota of Orthopteran in Relation to Gut Compartmentalisation.},
journal = {Insects},
volume = {16},
number = {6},
pages = {},
doi = {10.3390/insects16060555},
pmid = {40558985},
issn = {2075-4450},
support = {n/a//This project was financially supported by Mahasarakham University, Thailand and an ARES travel grant provided by the Wallonia-Brussels Federation as part of the Asia Europe Meeting (ASEM-DUO) programme./ ; },
abstract = {This review first provides an overview of the functional diversity of Orthoptera-associated microbiota and the services they provide to their hosts. However, data are widely scattered across the different families studied, making it difficult to establish whether a core microbiota is present. The abundance of some genera (Pantoea, Enterococcus, Enterobacter, Acinetobacter) is associated with the degradation of cellulose compounds, although their clear contribution remains to be determined. In addition, P. agglomerans may play a role in the production of aggregation pheromones in the desert locust. In terms of gut compartmentalisation, the diversity of the bacterial community in the foregut appears to be highly variable between individuals and species, whereas it is more uniform in other parts of the gut. Metabolic pathways of the gut microbiota revealed differences in amino acid metabolism between the midgut and hindgut. Bacteria in the midgut are associated with amino acid synthesis and anaerobic metabolism, whereas pathways in the hindgut may be involved in amino acid catabolism and ace-tyl-CoA-mediated processes. Further research is needed to better understand these different components of the bacterial community in digestive processes, and to identify bacterial species of particular interest in explaining species' lifestyles or for bioconversion.},
}

@article {pmid40558984,
year = {2025},
author = {Crane, YM and Crane, CF and Subramanyam, S and Schemerhorn, BJ},
title = {Shotgun Metagenome Analysis of Two Schizaphis graminum Biotypes over Time With and Without Carried Cereal Yellow Dwarf Virus.},
journal = {Insects},
volume = {16},
number = {6},
pages = {},
doi = {10.3390/insects16060554},
pmid = {40558984},
issn = {2075-4450},
support = {5020-21000-000-D//USDA-ARS Research Project/ ; },
abstract = {The greenbug aphid (Schizaphis graminum (Rondani)) is a major pest of wheat and an important vector of wheat viruses. An RNA-seq study was conducted to investigate the microbial effects of two greenbug genotypes, the presence or absence of cereal yellow dwarf virus, and the condition of the wheat host over a 20-day time course of unrestricted greenbug feeding. Messenger RNA reads were mapped to ca. 47,000 bacterial, 1218 archaeal, 14,165 viral, 571 fungal, and 94 protozoan reference or representative genomes, plus greenbug itself and its wheat host. Taxon counts were analyzed with QIIME2 and DESeq2. Distinct early (days 1 through 10) and late (days 15 and 20) communities differed in the abundance of typical enteric genera (Shigella, Escherichia, Citrobacter), which declined in the late community, while the ratio of microbial to greenbug read counts declined 50% and diversity measures increased. The nearly universal aphid endosymbiont, Buchnera aphidicola, accounted for less than 25% of the read counts in both communities. There were 302 differentially expressed (populated) genera with respect to early and late dates, while 25 genera differed between the greenbug genotypes and nine differed between carrier and virus-free greenbugs. The late community was likely responding to starvation as the wheat host succumbed to aphid feeding. Our results add to basic knowledge about aphid microbiomes and offer an attractive alternative method to assess insect microbiomes.},
}

@article {pmid40556890,
year = {2025},
author = {Ohata, Y and Tagami, Y},
title = {Antibiotic agrochemical treatment reduces endosymbiont infections and alters population dynamics in leafminers, thrips, and parasitoid wasps.},
journal = {Frontiers in microbiology},
volume = {16},
number = {},
pages = {1605308},
pmid = {40556890},
issn = {1664-302X},
abstract = {INTRODUCTION: The agricultural pests Liriomyza trifolii (Diptera: Agromyzidae) and Hercinothrips femoralis (Thysanoptera: Thripidae) harbor the endosymbiont Wolbachia, which induces cytoplasmic incompatibility and thelytokous parthenogenesis (asexual reproduction of female offspring without fertilization), respectively. The parasitoid Neochrysocharis formosa (Hymenoptera: Eulophidae), a natural enemy of leaf miners, is infected with Rickettsia, which also induces thelytokous parthenogenesis. Although symbionts can be eliminated in laboratory settings using antibiotics mixed with physical manipulation, the effects of agrochemical antibiotics designed for plant disease control on these insects and their symbionts remain unexplored. This study investigated the effects of MycoShield, a commercially available agrochemical containing 17% oxytetracycline, on symbiont-infected populations of these three insect species.

METHODS: MycoShield was applied to kidney bean plants or mixed into honey to expose L. trifolii, H. femoralis, and N. formosa to oxytetracycline. Offspring were screened for symbiont presence using PCR, and infection frequencies were compared across treatment concentrations. Additionally, H. femoralis populations were monitored in caged conditions under continuous exposure to treated plants.

RESULTS: At standard concentrations (1,000-fold dilution), MycoShield eliminated Wolbachia from L. trifolii and H. femoralis, resulting in L. trifolii producing uninfected offspring and H. femoralis producing only uninfected males. Similarly, Rickettsia was eliminated from N. formosa when adults ingested MycoShield-mixed honey. Additionally, N. formosa appeared to ingest the antibiotic indirectly by parasitizing L. trifolii larvae that had fed on treated leaves. Symbiont elimination was dose-dependent. Long-term exposure led to a substantial reduction in H. femoralis populations. Two out of eleven cages experienced complete extinction by day 100, likely due to genetic drift resulting from severe reproductive bottlenecks.

DISCUSSION: These findings demonstrate the potential of agrochemical antibiotics such as MycoShield as insecticidal agents targeting symbiont-mediated reproduction, with possible applications in sterile insect techniques. Further research is required to optimize efficacy and assess feasibility under field conditions.},
}

@article {pmid40552854,
year = {2025},
author = {Madsen, CS and Makela, AV and Maduka, CV and Greeson, EM and Tundo, A and Ural, E and Kulkarni, SH and Zarea, AA and Kiupel, M and Sayadi, M and Contag, CH},
title = {Engineered Endosymbionts that Modulate Primary Macrophage Function and Attenuate Tumor Growth by Shifting the Tumor Microenvironment.},
journal = {ACS applied bio materials},
volume = {},
number = {},
pages = {},
doi = {10.1021/acsabm.5c00590},
pmid = {40552854},
issn = {2576-6422},
abstract = {Modulating gene expression in macrophages can be used to improve tissue regeneration and redirect tumor microenvironments (TMEs) toward positive therapeutic outcomes. We have developed Bacillus subtilis as an engineered endosymbiont (EES) capable of residing inside the eukaryotic host cell cytoplasm and controlling the fate of macrophages. Secretion of mammalian transcription factors (TFs) from B. subtilis that expresses listeriolysin O (LLO; allowing the EES to escape destruction by the macrophage) modulated expression of surface markers, cytokines, and chemokines, indicating functional changes in a macrophage/monocyte cell line. The engineered B. subtilis LLO TF strains were evaluated in murine bone marrow-derived macrophages (BMDMs) by flow cytometry, chemokine/cytokine profiling, metabolic assays, and RNA-Seq delivery of TFs by the EES shifted BMDM gene expression, production of cytokine and chemokines, and metabolic patterns, indicating that the TF strains could guide primary macrophage function. Thereafter, the ability of the TF strains to alter the TME was characterized in vivo in an orthotopic murine model of triple-negative breast cancer to assess therapeutic effects. The TF strains altered the TME by shifting immune cell composition and attenuating tumor growth. Additionally, multiple doses of the TF strains were well-tolerated by the mice. The use of B. subtilis LLO TF strains as EES showed promise as a unique cancer immunotherapy by directing the immune function intracellularly. The uses of EES could be expanded to modulate other mammalian cells over a range of biomedical applications.},
}

@article {pmid40535948,
year = {2025},
author = {Pollmann, M and Reinisch, R and von Berg, L and Avidan King, M and Geiselmann, M and Käppeler, LM and Leibson, R and Traub, N and Steidle, JLM and Gottlieb, Y},
title = {Male-dependent resistance to Spiroplasma-induced cytoplasmic incompatibility.},
journal = {Royal Society open science},
volume = {12},
number = {6},
pages = {250545},
pmid = {40535948},
issn = {2054-5703},
abstract = {Cytoplasmic incompatibility (CI) caused by bacterial endosymbionts is an embryonic developmental failure between infected host males and uninfected females. Although even closely related hosts can have different CI phenotypes, little is known on the resistance mechanism in non-susceptible hosts. The parasitoid wasp species complex of Lariophagus distinguendus encompasses at least three species, termed clades A, B and C. All three species contain strains infected with the endosymbiotic bacterium Spiroplasma, which causes CI in clade A. We studied the relatedness of Spiroplasma in the species complex, the occurrence of CI in selected strains, and the effect of host strain and sex on CI induction. According to multi-locus sequence typing, all host species carry the same sDis strain. CI was absent in strains of clades B and C. Cross-transferring sDis revealed a male-dependent CI resistance in clade B. Together, this suggests a single infection event in the ancestor of all L. distinguendus clades. Some L. distinguendus strains are susceptible to CI, others are resistant. At least in one strain, resistance to CI is male-dependent, as theory predicts, supporting male-dependent traits as drivers for loss of CI-inducing bacteria. These results facilitate future studies on the mechanism of Spiroplasma-induced CI and its resistance.},
}

@article {pmid40534619,
year = {2025},
author = {Hoffmann, AA and Cooper, BS},
title = {Changes in the frequency of facultative endosymbionts in insect populations: overview and applications.},
journal = {Entomologia generalis},
volume = {45},
number = {2},
pages = {351-368},
pmid = {40534619},
issn = {2363-7102},
abstract = {Many insect endosymbionts are facultative from the host perspective, and their population frequencies across time and space will depend on their transmission fidelity and effects on host fitness. These effects and transmission rates in turn depend on the environmental and host genetic contexts where the endosymbionts occur. Endosymbionts like Wolbachia and Cardinium affect host reproduction to produce transient or persistent presence/absence polymorphisms, while other endosymbionts like Regiella and Hamiltonella persist through providing host fitness benefits and transmitting horizontally. Evolutionary changes in hosts and endosymbionts affect these impacts and endosymbiont polymorphisms in host populations and host sexes. We review this diversity of endosymbiont-host interactions and their influence on the usefulness of endosymbionts for applied strategies. Current strategies focus on endosymbionts driving useful traits to fixation (particularly Wolbachia suppression of arbovirus transmission by mosquitoes) or endosymbionts suppressing populations due to infected males sterilising females. Transinfected endosymbionts sourced from one species and microinjected into another have proven effective in these Wolbachia-mosquito strategies. Novel strategies involving transinfected Rickettsiella, Regiella and Wolbachia may decrease the impacts of pest invertebrates by suppressing pest numbers, reducing the capacity of vector hosts to transmit plant viral diseases or bolstering the effectiveness of natural enemies. Because many endosymbionts are already present in the environment, their applied use raises fewer safety concerns when compared to genetic modification, as supported by more than 13 years of field experiences with Wolbachia in mosquitoes that have not raised major concerns.},
}

@article {pmid40532926,
year = {2025},
author = {Jean-Claude, O and Sophie, G},
title = {Will anomalies in the field of EPN associated-bacteria lead to a new paradigm?.},
journal = {Journal of invertebrate pathology},
volume = {},
number = {},
pages = {108387},
doi = {10.1016/j.jip.2025.108387},
pmid = {40532926},
issn = {1096-0805},
abstract = {According to the prevailing monoxenic paradigm, entomopathogenic nematodes (EPNs) form specific association with endosymbiotic bacteria. However, many anomalies have been observed over the last 60 years, with bacterial taxa other than the known endosymbiont isolated in culture-based approaches or detected by next-generation sequencing. We have reconsidered the role of this EPN-associated microbiota - known as the second bacterial circle - in the life-cycle of EPNs. In this review, we present arguments supporting a role for certain taxa in the death of the insect and propose hypotheses concerning other properties of the bacteria involved in their interactions with EPNs. Should these functional hypotheses be confirmed, then the bacterial "anomalies" would no longer be regarded as such. Instead, they would form the basis for the establishment of a new paradigm, the polyxenic paradigm.},
}

@article {pmid40528998,
year = {2025},
author = {Tashyreva, D and Faktorová, D and Horák, A and Lukeš, J and Archibald, JM and Oatley, G and Sinclair, E and Santos, C and Paulini, M and Aunin, E and Gettle, N and Niu, H and McKenna, V and O'Brien, R and , and , and , and , and , },
title = {The genome sequences of the diplonemid protist Rhynchopus euleeides YPF1915 and its bacterial endosymbiont Candidatus Syngnamydia salmonis (Chlamydiota).},
journal = {Wellcome open research},
volume = {10},
number = {},
pages = {233},
pmid = {40528998},
issn = {2398-502X},
abstract = {We present a genome assembly of the diplonemid Rhynchopus euleeides (Euglenozoa; Diplonemea; Diplonemea; Diplonemidae). The genome sequence is 199.0 megabases long, with most of the assembly scaffolded into 88 chromosomal pseudomolecules. The multipartite mitochondrial genome and the 2.0 megabase genome of Ca. Syngnamydia salmonis, a bacterial endosymbiont of R. euleeides, were also sequenced and assembled.},
}

@article {pmid40527400,
year = {2025},
author = {Clodfelter, EB and Doña, J and Walden, KKO and Johnson, KP},
title = {Metagenomic analyses reveal three supergroups of Wolbachia in a single genus of feather-feeding lice (Penenirmus).},
journal = {Molecular phylogenetics and evolution},
volume = {},
number = {},
pages = {108387},
doi = {10.1016/j.ympev.2025.108387},
pmid = {40527400},
issn = {1095-9513},
abstract = {Insects with nutritionally limited diets often harbor bacterial endosymbionts that supplement their nutritional requirements. However, not all interactions between bacteria and insects are mutually beneficial. Wolbachia is a genus of bacteria that frequently causes cytoplasmic incompatibility and other reproductive parasitic effects on many of its arthropod hosts. In nematodes and some insects, however, Wolbachia is a nutritional mutualist. A lineage of Wolbachia closely related to mutualist strains has previously been identified in parasitic lice, including the louse genus Penenirmus (Ischnocera), which specializes in feeding on feathers. In this study, we used genome-resolved metagenomics to examine the diversity of Wolbachia across the genus Penenirmus, with a focus on evidence of long term associations with their hosts, which could indicate a mutualistic relationship. Phylogenomic analysis of over 100 genes from Wolbachia provided a well-resolved phylogeny of this bacterial genus. Across diverse species of the louse genus Penenirmus, genome-resolved metagenomic assemblies of Wolbachia from these insects revealed the presence of three different supergroups (B, F, and V). Supergroup V had not previously been known from lice. Cophylogenetic analysis revealed significant congruence between the Wolbachia and louse trees, although some branches showed incongruence. The Wolbachia in Penenirmus species from supergroups F and B showed evidence of potential mutualism by having long branches, cophylogenetic congruence with their louse hosts, and comparatively smaller genome sizes. Long branch attraction may be affecting the phylogenetic position of two lineages of Wolbachia, but the relative position of all other samples was comparatively stable.},
}

@article {pmid40525492,
year = {2025},
author = {Yuan, E and Du, B and Sun, Y},
title = {Reduction of Buchnera with rifampicin impairs the density-dependent induction of winged morph in pea aphid.},
journal = {Insect science},
volume = {},
number = {},
pages = {},
doi = {10.1111/1744-7917.70098},
pmid = {40525492},
issn = {1744-7917},
support = {2022YFD1400800//National Key Research and Development Program of China/ ; 32250002//National Natural Science Foundation of China/ ; 32400348//National Natural Science Foundation of China/ ; 2024M753220//China Postdoctoral Science Foundation/ ; 2023IOZ0307//Initiative Scientific Research Program, Institute of Zoology, CAS/ ; },
abstract = {Wing dimorphism is a critical trait that helps insects better adapt to environments. High population density and poor nutrition are known to induce winged morph in aphids. Buchnera aphidicola, an obligate endosymbiont of aphids, supplies the host with essential amino acids and B vitamins, while the mechanistic basis of Buchnera's role in density-dependent production of winged aphids is largely unclear. Reduction of Buchnera from maternal aphids or the 1st instar nymphs with antibiotic rifampicin reduced the proportion of winged aphids. In contrast, for the 2nd instar nymphs, reduction of Buchnera failed to decline the proportion of winged aphids, suggesting the 1st instar is a critical period for wing plasticity. Genes associated with amino acid transport and insulin signaling were identified by RNA sequencing as differentially expressed genes between rifampicin and dimethyl sulfoxide-treated 1st instar nymphs. Proton-assisted amino acid transporter 1 (PAT1), was down-regulated by rifampicin. Knockdown of PAT1 in 1st instar nymphs reduced the proportion of winged aphids. In addition, reduction of Buchnera with rifampicin up-regulated several marker genes of the insulin signaling pathway, and reduced the phosphorylation level of forkhead transcription factor subgroup O (FOXO), a determinant of wing morph downstream of insulin signaling. Application of FOXO phosphorylation inhibitor LY2780301 decreased the proportion of winged aphids, while the agonist SC79 increased the proportion of winged aphids. These results revealed that reduction of Buchnera sharply declined the proportion of winged aphids, indicating that the vertical transmission of Buchnera could bring on a maternal signal of crowding perception, which was required for the production of winged offspring.},
}

@article {pmid40523179,
year = {2025},
author = {Vaishally, and Pal, S and Thyagarajan, KR and Shukla, SP},
title = {An endosymbiotic origin of the crimson pigment from the lac insect.},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {122},
number = {25},
pages = {e2501623122},
doi = {10.1073/pnas.2501623122},
pmid = {40523179},
issn = {1091-6490},
support = {Ramalingaswami Fellowship//Department of Biotechnology, Ministry of Science and Technology, India (DBT)/ ; SRG/2021/000600//Department of Science and Technology, Ministry of Science and Technology, India (DST)/ ; Partner Group Funding//Max Planck Society, Germany/ ; },
mesh = {Animals ; *Symbiosis ; *Hemiptera/genetics/microbiology/metabolism ; *Pigments, Biological/metabolism/genetics ; Phylogeny ; Anthraquinones/metabolism ; },
abstract = {Symbioses with microorganisms expand the genetic and metabolic repertoire of many insects. The lac insect Kerria lacca (Hemiptera: Sternorrhyncha) is a phloem-feeding scale insect that is brightly colored due to the presence of natural polyhydroxy-anthraquinone pigments called laccaic acids. The deep red pigments possibly provide defense against pathogens and predators and are commercially important as dyes in textiles, lacquerware, and cosmetics. Laccaic acids are categorized as polyketides comprising an anthraquinone backbone decorated with tyrosine or its derivatives. However, the genetic basis of these pigments remains unknown, as insects are not known to produce aromatic polyketides or tyrosine de novo. Here, we sequence the genome of the lac insect and its two endosymbionts-Wolbachia and a hitherto unidentified, transovarially transmitted yeast-like symbiont (YLS). We found no evidence for the host or Wolbachia to be able to synthesize the pigments. The pigments and their precursors were also not detected in the host plant. Genomic, transcriptomic, and metabolomic analyses combined with fluorescence microscopy identified and characterized YLS as the sole producer of the pigment's polyketide backbone and tyrosine moiety, demonstrating an endosymbiotic origin of the lac pigments. A nonreducing polyketide synthase gene cluster encoding the laccaic acid backbone was identified. Furthermore, the YLS genome encoded essential amino acids and vitamins that are deficient in the insect's phloem diet. Experimental fungicide-treated insects exhibited reduced concentrations of laccaic acids and tyrosine, along with decreased body size and weight, indicating a mutualistic association between the lac insect and its YLS.},
}

Animals
*Symbiosis
*Hemiptera/genetics/microbiology/metabolism
*Pigments, Biological/metabolism/genetics
Phylogeny
Anthraquinones/metabolism

@article {pmid40521888,
year = {2025},
author = {Lesiczka, PM and Azagi, T and Krawczyk, AI and Scott, WT and Dirks, RP and Simo, L and Dobler, G and Nijsse, B and Schaap, PJ and Sprong, H and Koehorst, JJ},
title = {Deep sequencing of 16 Ixodes ricinus ticks unveils insights into their interactions with endosymbionts.},
journal = {mSystems},
volume = {},
number = {},
pages = {e0050725},
doi = {10.1128/msystems.00507-25},
pmid = {40521888},
issn = {2379-5077},
abstract = {Ixodes ricinus ticks act as vectors for numerous pathogens that present substantial health threats. Additionally, they harbor vertically transmitted symbionts, some of which have been linked to diseases. The difficulty of isolating and cultivating these symbionts has hampered our understanding of their biological role, their potential to cause disease, and their modes of transmission. To expand our understanding of the tick symbiont Midichloria mitochondrii and Rickettsia helvetica, which has been linked to disease in humans, we utilized deep sequencing on 16 individual adult female ticks collected from coastal dune and forested areas in the Netherlands. By employing a combination of second- and third-generation sequencing techniques, we successfully reconstructed the complete genomes of M. mitochondrii from 11 individuals, R. helvetica from eight individuals, and the mitochondrial genome from all ticks. Additionally, we visualized the location of R. helvetica in tick organs and constructed genome-scale metabolic models (GEMs) of both symbionts to study their environmental dependencies. Our analysis revealed a strong cophylogeny between M. mitochondrii and mitochondrial genomes, suggesting frequent maternal transmission. In contrast, the absence of cophylogeny between R. helvetica and the mitochondrial genomes, coupled with its presence in the receptaculum seminis of I. ricinus females, raises the possibility of paternal transmission of R. helvetica. Notably, the genetic diversity of R. helvetica was found to be very low, except for the rickA virulence gene, where the presence of up to 13 insertions of a 33 nt-long repeat led to significant variability. However, this variation could not account for the differences in infection prevalence observed across eight distinct locations in the Netherlands. By employing deep sequencing, it becomes feasible to extract complete genomes and genetic data of symbionts directly from their host organisms. This methodology serves as a robust means to gain fresh insights into their interactions. Our observations, which suggest paternal transmission of R. helvetica, a relatively unexplored mode of transmission in ticks, require validation through experimental investigations. The genetic variations identified in the rickA virulence gene of R. helvetica have the potential to influence the infectivity and transmission dynamics of R. helvetica.IMPORTANCETicks are vectors of numerous human pathogens; however, the microbial interactions within ticks and the mechanisms governing pathogen transmission remain poorly understood. This study uses deep sequencing of individual Ixodes ricinus to reconstruct high-quality genomes of endosymbionts and the mitochondrion of the tick, revealing previously undetected microbial dynamics. Notably, we recovered low-abundance Rickettsia and Midichloria genomes from single ticks and present evidence that suggests paternal transmission of R. helvetica. These findings offer novel insights into the ecology and evolution of tick-associated microbes and have implications for understanding the origins and spread of tick-borne diseases.},
}

@article {pmid40511620,
year = {2025},
author = {Hanley, TC and Gehring, CA and Deckert, RJ and Mortazavi, B and Richards, CL and Hughes, AR},
title = {Intraspecific variation in plant-fungal interactions across tidal elevation in a salt marsh.},
journal = {The New phytologist},
volume = {},
number = {},
pages = {},
doi = {10.1111/nph.70262},
pmid = {40511620},
issn = {1469-8137},
support = {IOS-1556087//Division of Integrative Organismal Systems/ ; IOS-1556738//Division of Integrative Organismal Systems/ ; IOS-1556820//Division of Integrative Organismal Systems/ ; },
abstract = {Interspecific interactions vary depending on environmental and genetic factors, with intraspecific variation potentially altering these relationships. Specifically, intraspecific variation within host plants and their endosymbionts may affect above- and belowground interactions depending on environmental conditions. We examined how intraspecific variation within the salt marsh foundation species Spartina alterniflora and a common fungal root endosymbiont (Lulworthia sp.) affected their interactions. We conducted a glasshouse experiment comparing interactions between Spartina growth forms (tall-form from low marsh and short-form from high marsh) and Lulworthia isolates from different marsh locations, and a laboratory experiment exposing Lulworthia isolates from both endpoints of a tidal elevation gradient to different salinities. Intraspecific variation affected fungal characteristics, plant traits, and plant-fungal interactions. Lulworthia isolates distinguished by a single-nucleotide polymorphism had distinct morphologies and different salinity-dependent growth rates. Spartina origin zone affected plant responses. Fungal treatment also affected plant performance: one isolate reduced Spartina density, height, biomass, and respiration - particularly for tall-form plants - whereas the other isolate had neutral to positive effects relative to the control. Our results highlight how intraspecific variation in both fungal isolates and plant genotypes shapes plant-fungal interactions and mediates the capacity of host plants to respond to changing conditions depending on plant ecotype.},
}

@article {pmid40510671,
year = {2025},
author = {Ferreira, LYM and Santos, JPN and Souza, DGDN and Orellana, LCB and de Santana, SF and Sousa, AG and Fonseca, PLC and Silva, AGS and Santos, VC and de Faria, IJDS and Olmo, RP and Pacheco, LGC and Costa, MGC and Pirovani, CP and Oliveira, AR and Aguiar, ERGR},
title = {Potential effect of Wolbachia on virus restriction in the spider mite T. truncatus.},
journal = {Frontiers in microbiology},
volume = {16},
number = {},
pages = {1570606},
pmid = {40510671},
issn = {1664-302X},
abstract = {The mite T. truncatus is a significant agricultural pest and may serve as a potential vector for viral transmission. However, the virome of T. truncatus remains understudied. Through metatranscriptomic analyses of publicly available data, we uncovered a diverse range of viruses associated with the spider mite, including crop-infecting pathogenic species such as Potato virus Y and Cherry virus A, and fourteen previously unknown viruses across several families (e.g., Virgaviridae, Dicistroviridae, Kitaviridae, Betaflexiviridae, and Nudiviridae). Taking advantage of mite samples under different conditions, we also assessed the impact of biotic (Wolbachia and Spiroplasma infection) and abiotic stresses (pesticide exposure and temperature stress) on the T. truncatus virome. Interestingly, Wolbachia appeared to restrict viral infections in T. truncatus by reducing viral diversity and abundance, with a pronounced effect on dicistroviruses. Surprisingly, a similar effect also observed with Spiroplasma. However, the viral restriction phenotype vanishes in co-infected mites. Transcriptomics analysis of singly-infected mites revealed upregulation of piRNA and autophagy-related genes, while lipid metabolism processes-related genes were downregulated, indicating an endosymbiont-sharing mechanisms of viral interference. Although the impact of abiotic stressors on the virome was not statistically significant, Potato virus Y and TtDV-2 viruses were absent in abamectin-exposed mites, suggesting a potential reduction in the viral diversity, while heat-stressed mites exhibited slightly higher viral diversity compared to those raised at regular temperatures. Overall, our work provides a detailed analysis of the T. truncatus virome, shedding light on how endosymbionts and environmental factors shape viral dynamics and offering potential insights for pest management strategies.},
}

@article {pmid40503031,
year = {2025},
author = {Junsiri, W and Taweethavonsawat, P},
title = {New insights into the genetic diversity, phylogeny, and immunogenic potential of the wsp gene in Wolbachia endosymbionts in Brugia malayi and Brugia pahangi.},
journal = {Current research in parasitology & vector-borne diseases},
volume = {7},
number = {},
pages = {100272},
pmid = {40503031},
issn = {2667-114X},
abstract = {Wolbachia spp. are intracellular, maternally inherited bacteria that infect a wide range of arthropods. These bacteria influence reproductive traits in their hosts and are used in mosquito-borne virus control programmes. This study investigates the Wolbachia surface protein (WSP), a potential trigger of innate immune responses. The wsp gene was amplified by polymerase chain reaction, cloned, and sequenced. Phylogenetic analysis showed that wsp sequences from Wolbachia endosymbionts of Brugia pahangi and B. malayi formed two clades within the supergroup D. The wsp sequences were highly conserved, with 99-100% sequence identity across global isolates. Haplotype analysis revealed 13 distinct wsp haplotypes. The average antigenic score of the WSP protein was 1.029 for B. malayi and 1.026 for B. pahangi. MHC-NP analysis predicted eight antigen ligands for B. malayi and six for B. pahangi. Notably, a shared antigen ligand (VIADQKHGF) was identified for both species, associated with dog leukocyte antigens (DLA-8850101, DLA-8803401, and DLA-8850801). Additionally, a conserved ligand region (ALVMLLSLSNSAFSD) was identified in the WSP of B. malayi, corresponding to human leukocyte antigens (HLA-DR alleles HLA-DRB1∗04:04 and HLA-DRB1∗04:01). These findings provide new insights into the phylogenetic classification, sequence conservation, and immunogenic potential of the WSP protein in Wolbachia endosymbionts of Brugia spp.},
}

@article {pmid40495559,
year = {2025},
author = {Ball, S and Baurain, D and Leleu, M and Lafontaine, I and Cenci, U and Colleoni, C and Vallon, O and Greub, G and Weber, A and Bhattacharya, D},
title = {[Not Available].},
journal = {Comptes rendus biologies},
volume = {348},
number = {},
pages = {107-135},
doi = {10.5802/crbiol.176},
pmid = {40495559},
issn = {1768-3238},
abstract = {Endosymbionts are very common in nature, offering multiple occasions to recapitulate events that have led to the generation of mitochondria and plastids. However, both these organelles are unique because they are thought to derive from two individual events that gave rise to all eukaryotes and the plastids in algae and plants (excluding Paulinella chromatophora), respectively. This review focuses on the differences and similarities existing between extant endosymbionts and the two major endosymbiont derived organelles: the mitochondria and plastids. Emphasis is put on recent developments that point to the major role of intracellular pathogens in the establishment of these organelles. We argue that metabolic integration of bacterial endosymbionts into mitochondria and plastids required an unusually high degree of preadaptation not shared by most extant endosymbionts. We propose that this was achieved by either recruiting intracellular bacterial pathogens as "helper genomes" providing needed gene products, or by selecting endosymbionts destined to become organelles directly from such obligate intracellular bacteria.},
}

@article {pmid40495375,
year = {2025},
author = {Fattar, N and Louni, M and Buysse, M and Floriano, AM and Bertaux, J and Cantereau, A and Rivero, A and Bruley, M and McCoy, KD and Delafont, V and Boulanger, N and Vavre, F and Bouchon, D and Duron, O},
title = {Evolutionary Convergence of Nutritional Symbionts in Ticks.},
journal = {Environmental microbiology reports},
volume = {17},
number = {3},
pages = {e70120},
doi = {10.1111/1758-2229.70120},
pmid = {40495375},
issn = {1758-2229},
support = {ANR- 20-CE34-0002//Agence Nationale de la Recherche/ ; ANR-10-LABX-04-01//Agence Nationale de la Recherche/ ; ANR-10-LABX-25-01//Agence Nationale de la Recherche/ ; ANR-21-CE02-0002//Agence Nationale de la Recherche/ ; //Université de Montpellier, KIM RIVE, MUSE/ ; //Région Occitanie Pyrénées-Méditerranée, RIVOC/ ; },
mesh = {Animals ; *Symbiosis ; *Ticks/microbiology/physiology ; *Coxiella/genetics/physiology/metabolism ; *Francisella/genetics/physiology/metabolism ; *Biological Evolution ; Phylogeny ; Heme/biosynthesis ; *Bacteria/genetics/classification/metabolism ; },
abstract = {Symbiosis with bacteria is essential for the survival of animals with an obligate blood-feeding lifestyle. In ticks, two distinct bacterial lineages, Coxiella-like and Francisella-like endosymbionts, have independently evolved into nutritional symbionts, converging on a key biochemical function for the tick's survival and growth: the production of three B vitamins. In this study, we carried out comparative analyses across multiple tick species and characterised remarkable similarities in their tissue localisation, particularly in organs important for nutrient metabolism and maternal transmission to progeny. In these organs, both symbionts colonise similar intracellular niches, residing within membrane-bound, replicative vacuoles that occupy a substantial part of the cytoplasm of tick cells. Despite extensive genomic reduction, both symbionts have retained pathways for the biosynthesis of B vitamins and, in some cases, chorismate, a precursor used for the production of serotonin by ticks. However, differences exist: while Coxiella-like endosymbionts lack the ability to synthesise heme, Francisella-like endosymbionts possess a complete heme biosynthesis pathway and may potentially provide ticks with this essential cofactor. Overall, these phenotypic and genomic characteristics reveal a broad convergence among symbiotic interactions across major tick families, highlighting the essential role of symbiosis in tick nutrition, feeding behaviour, blood intake and subsequently in pathogen transmission.},
}

Animals
*Symbiosis
*Ticks/microbiology/physiology
*Coxiella/genetics/physiology/metabolism
*Francisella/genetics/physiology/metabolism
*Biological Evolution
Phylogeny
Heme/biosynthesis
*Bacteria/genetics/classification/metabolism

@article {pmid40492768,
year = {2025},
author = {Sun, W and Li, C and Jiang, L and Pan, Z and Qiao, G and Chen, J},
title = {Complete genome sequence of the obligate endosymbiont Buchnera aphidicola of the poplar bark aphid Pterocomma populeum.},
journal = {Microbiology resource announcements},
volume = {},
number = {},
pages = {e0037925},
doi = {10.1128/mra.00379-25},
pmid = {40492768},
issn = {2576-098X},
abstract = {We report the complete genome sequence of Buchnera aphidicola from the aphid Pterocomma populeum using Illumina NovaSeq X Plus platform. The assembled genome is 588,150 bp with a guanine-cytosine content of 24%.},
}

@article {pmid40489578,
year = {2025},
author = {Cassens, J and Villalta, M and Aguirre, S and Ecklund, L and Stenger, T and Abdi, I and Venigalla, S and Shiffman, E and Bastug, K and Thielen, BK and Faulk, C},
title = {The Genome of the American Dog Tick (Dermacentor variabilis).},
journal = {G3 (Bethesda, Md.)},
volume = {},
number = {},
pages = {},
doi = {10.1093/g3journal/jkaf130},
pmid = {40489578},
issn = {2160-1836},
abstract = {The American dog tick (Dermacentor variabilis) is a vector of zoonotic pathogens in North America that poses emerging threats to public health. Despite its medical importance, genomic resources for D. variabilis remain scarce. Leveraging long-read nanopore sequencing, we generated a high-quality genome assembly for D. variabilis with a final size of 2.15 Gb, an N50 of 445 kb, and a BUSCO completeness score of 95.2%. Comparative BUSCO analyses revealed fewer duplicate genes in our assembly than in other Dermacentor genomes, indicating improved haplotype resolution. The mitochondrial genome, assembled as a single circular contig, clustered monophyletically with D. variabilis isolates from the Upper Midwest, corroborating regional phylogenetic relationships. Repetitive element analysis identified 61% of the genome as repetitive, dominated by LINEs and LTR elements, with 24% remaining unclassified, underscoring the need for further exploration of transposable elements in tick genomes. Gene annotation predicted 21,722 putative genes, achieving a protein BUSCO completeness of 80.88%. Additionally, genome-wide methylation analysis revealed 9.9% global 5mC methylation, providing the first insights into epigenetic modifications in D. variabilis. Further, nanopore sequencing detected Rickettsia montanensis and a non-pathogenic Francisella-like endosymbiont. These findings expand our understanding of tick genomics and epigenetics, offering valuable resources for comparative studies and evolutionary analyses.},
}

@article {pmid40483691,
year = {2025},
author = {Burgmer, S and Meyer Zu Altenschildesche, FL and Gyenis, A and Lee, HJ and Vilchez, D and Giavalisco, P and Fichant, A and Uhlirova, M and Storelli, G},
title = {Endosymbiont control through non-canonical immune signaling and gut metabolic remodeling.},
journal = {Cell reports},
volume = {44},
number = {6},
pages = {115811},
doi = {10.1016/j.celrep.2025.115811},
pmid = {40483691},
issn = {2211-1247},
abstract = {Animals coexist with bacteria and need to keep these microorganisms under tight control. To achieve such control, pattern recognition receptors (PRRs) sense bacterial cues and induce the production of antimicrobials. Here, we uncover a metabolic arm in the control of symbionts by PRRs. We show that, in Drosophila, the PRRs PGRP-LC and PGRP-LE act independently of canonical NF-κB signaling to repress essential metabolic functions in the gut, such as digestion and central carbon metabolism. This metabolic switch affects commensal populations and drastically reduces intestinal and systemic populations of the intracellular parasite Wolbachia. We propose that intestinal metabolic remodeling complements immune responses by imposing nutrient restriction on intracellular bacteria, whose lifestyle protects them from antimicrobials. Our findings reveal a role for PRRs in bacterial control beyond canonical immune pathways and provide insights into how microbial signals modulate symbiotic populations but also nutrition and metabolism in animals.},
}

@article {pmid40475605,
year = {2025},
author = {Merk, LN and Jones, TA and Eddy, SR},
title = {Prevalence of Group II Introns in Phage Genomes.},
journal = {bioRxiv : the preprint server for biology},
volume = {},
number = {},
pages = {},
doi = {10.1101/2025.05.22.655115},
pmid = {40475605},
issn = {2692-8205},
abstract = {Although bacteriophage genomes are under strong selective pressure for high coding density, they are still frequently invaded by mobile genetic elements (MGEs). Group II introns are MGEs that reduce host burden by autocatalytically splicing out of RNA before translation. While widely known in bacterial, archaeal, and eukaryotic organellar genomes, group II introns have been considered absent in phage. Identifying group II introns in genome sequences has previously been challenging because of their lack of primary sequence similarity. Advances in RNA structure-based homology searches using covariance models has provided the ability to identify the conserved secondary structures of group II introns. Here, we discover that group II introns are widely prevalent in phages from diverse phylogenetic backgrounds, from endosymbiont phage to jumbophage.},
}

@article {pmid40475578,
year = {2025},
author = {DuBose, JG and Uhm, T and Bowen, J and Fiedorek, P and Hoogshagen, M and Haselkorn, TS and DiSalvo, S},
title = {The roles of dispersal limitation and pre-adaptation in shaping Paraburkholderia endosymbiont frequencies in social amoeba communities.},
journal = {bioRxiv : the preprint server for biology},
volume = {},
number = {},
pages = {},
doi = {10.1101/2025.05.20.654931},
pmid = {40475578},
issn = {2692-8205},
abstract = {Endosymbiotic interactions have long played fundamental roles in shaping the evolution and diversification of eukaryotes. However, we still have a limited understanding of how ecological processes govern the distribution of endosymbionts that are still segregating in host populations. To contribute to this understanding, here we use the interactions between Paraburkholderia endosymbionts and their Dictyostelid social amoeba hosts as a model system to investigate the role of dispersal, a fundamental ecological process, in shaping the distribution and evolution of endosymbiotic interactions. We first found that patterns of endosymbiont diversification were highly biogeographic, suggesting a significant degree of dispersal limitation. We then experimentally mediated the dispersal of several endosymbiont species into environments with multiple host species and found that each symbiont was able to sustain a high prevalence in each host population. The benefit/detriment of these mediated interactions did not change with increasing phylogenetic distance from what is suspected to be the focal amoeba host species in nature. Taken together, our findings suggest Paraburkholderia endosymbionts are generally pre-adapted to occupy a variety of Dictyostelid host environments, and their distribution among host populations is subject to a high degree of dispersal limitation. Overall, our findings have significant implications for our understanding of how ecological processes facilitate and limit the evolution of endosymbiotic interactions.},
}

@article {pmid40468534,
year = {2025},
author = {Swenie, RA and Cubeta, MA and Langer, GJ and Lawrey, JD and Sikaroodi, M and Smith, ME and Matheny, PB},
title = {A phylogenetic study of the Cantharellales supports recognition of four families and independent gains of biotrophic nutritional modes.},
journal = {American journal of botany},
volume = {},
number = {},
pages = {e70054},
doi = {10.1002/ajb2.70054},
pmid = {40468534},
issn = {1537-2197},
abstract = {PREMISE: The agaricomycete order Cantharellales contains approximately 1000 species of fungi characterized by diverse morphological forms, ecological guilds, and nutritional modes. Examples include coralloid lichens that form symbioses with unicellular green algae, bulbil-forming lichenicolous species, corticioid free-living fungi that degrade dead sources of organic carbon, pathogens that cause plant disease, orchid root endosymbionts, and ectomycorrhizal fungi including popular edible mushrooms. However, evolutionary relationships in the Cantharellales remain poorly understood due to conflicting estimates based on ribosomal DNA loci.

METHODS: We constructed a five-gene phylogeny of the Cantharellales using data from 301 specimens to evaluate family-level relationships. We used penalized likelihood to estimate divergence times and ancestral state reconstruction to test the hypothesis of multiple independent origins of biotrophic ecologies in the order and whether those transitions are younger than the divergence times of associated plant or lichen hosts.

RESULTS: Four monophyletic families were recovered with strong support: Botryobasidiaceae, Ceratobasidiaceae, Hydnaceae s.l., and Tulasnellaceae, with Hydnaceae containing the greatest species richness and morphological diversity. Our results suggest the Cantharellales diverged during the Carboniferous period with subsequent diversification following the Permian-Triassic extinction. Ancestral state reconstruction supports a saprotrophic most recent common ancestor with at least three transitions to an ectomycorrhizal ecology, multiple transitions to a lichenicolous habit with one or more subsequent transitions to mutualistic nutritional modes, four transitions to an orchid mycorrhizal ecology, and two transitions to a lichenized lifestyle.

CONCLUSIONS: This study represents the first comprehensive examination of the evolution of form and function across this ecologically and morphologically diverse order of fungi.},
}

@article {pmid40467487,
year = {2025},
author = {Nakayama, T and Harada, R and Yabuki, A and Nomura, M and Shiba, K and Inaba, K and Inagaki, Y},
title = {Marked Genome Reduction Driven by a Parasitic Lifestyle: Two Complete Genomes of Endosymbiotic Bacteria Possibly Hosted by a Dinoflagellate.},
journal = {Microbes and environments},
volume = {40},
number = {2},
pages = {},
doi = {10.1264/jsme2.ME25005},
pmid = {40467487},
issn = {1347-4405},
mesh = {*Symbiosis ; Phylogeny ; *Genome, Bacterial ; *Dinoflagellida/microbiology/physiology ; *Gammaproteobacteria/genetics/classification/isolation & purification/physiology ; Base Composition ; Gene Transfer, Horizontal ; Genome Size ; },
abstract = {Bacteria with endosymbiotic lifestyles often show marked genome reduction. While the shrinkage of genomes in intracellular symbionts of animals, including parasitic bacteria, has been extensively exami-ned, less is known about symbiotic bacteria associated with single-celled eukaryotes. We herein report the genomes of two novel gammaproteobacterial lineages, RS3 and XS4, identified as putative parasitic endosymbionts of the dinoflagellate Citharistes regius. Phylogenetic ana-lyses suggest that RS3 and XS4 belong to the family Fastidiosibacteraceae within the order Beggiatoales, forming independent lineages therein. The genomes of RS3 and XS4 are 529 and 436‍ ‍kbp in size, respectively, revealing marked reductions from related bacterial genomes. XS4, which has a very reduced genome with a low GC content, uses a different genetic code, in which UGA assigned tryptophan. The small genomes of RS3 and XS4 encode a limited number of proteins, retaining only approximately 20% of the predicted ancestral proteome. Metabolic reconstruction suggests that RS3 and XS4 are parasitic symbionts that are heavily dependent on their host for essential metabolites. Furthermore, we found that the ancestor of both genomes likely acquired an ADP:ATP antiporter gene via horizontal gene transfer, an event that may have enabled their evolution as energy parasites by facilitating the acquisition of ATP from their host. These results on novel bacteria with highly reduced genomes expand our understanding of the phylogenetic and genomic diversities of endosymbiotic bacteria in protists.},
}

*Symbiosis
Phylogeny
*Genome, Bacterial
*Dinoflagellida/microbiology/physiology
*Gammaproteobacteria/genetics/classification/isolation & purification/physiology
Base Composition
Gene Transfer, Horizontal
Genome Size

@article {pmid40459778,
year = {2025},
author = {Chu, Y and Campbell, E and Dzimianski, M and Evans, CC and Pulaski, C and Sakamoto, K and Moorhead, AR},
title = {In vitro molting of Dirofilaria immitis third-stage larvae derived from microfilariae collected from doxycycline-treated dogs.},
journal = {Parasitology research},
volume = {124},
number = {6},
pages = {59},
pmid = {40459778},
issn = {1432-1955},
mesh = {Animals ; *Dirofilaria immitis/drug effects/microbiology/growth & development/physiology ; *Doxycycline/pharmacology/administration & dosage/therapeutic use ; Dogs ; Larva/drug effects/microbiology/growth & development/physiology ; Wolbachia/drug effects/isolation & purification ; *Dirofilariasis/parasitology/drug therapy ; *Dog Diseases/parasitology/drug therapy ; *Anti-Bacterial Agents/pharmacology ; *Microfilariae/drug effects/microbiology ; *Molting/drug effects ; },
abstract = {Dirofilaria immitis, also known as canine heartworm, contains an endosymbiont, Wolbachia, in all life stages. The antibiotic, doxycycline, has been incorporated into heartworm treatment protocols to eliminate Wolbachia. Previous studies indicate that subsequent infection cannot be established using viable third-stage larvae (L3) developed from doxycycline-treated microfilariae (mf). The stages in which the development of larvae is impacted by doxycycline remain unknown. We examined the impact of doxycycline on the third-stage to fourth-stage larval molt, as it is the first molt of D. immitis after it invades the vertebrate host. Microfilaremic blood was collected weekly from D. immitis-infected dogs with or without doxycycline treatment at 10 mg/kg as recommended by the American Heartworm Society. Blood was collected weekly until the end of doxycycline treatment. The blood was used for L3 production and mf isolation. Wolbachia levels in mf and L3 were measured using real-time quantitative PCR. L3 were cultured in vitro for 9 days to assess whether molting occurred. The Fisher's exact test and Bonferroni correction were used for statistical analysis. The molting of L3 from the doxycycline-treated groups did not show a significant difference compared to the L3 from the control group at weeks 0, 1, 2, 3, and 4. The Wolbachia levels in mf and L3 decreased starting from 7 days post-treatment and remained less than five percent of controls throughout the treatment. Doxycycline treatment can eliminate Wolbachia in both mf and subsequently developed L3. The molts of the mf to L3 in the mosquito and the L3 to L4 molt in vitro do not appear to be impacted by the reduction or elimination of Wolbachia.},
}

Animals
*Dirofilaria immitis/drug effects/microbiology/growth & development/physiology
*Doxycycline/pharmacology/administration & dosage/therapeutic use
Dogs
Larva/drug effects/microbiology/growth & development/physiology
Wolbachia/drug effects/isolation & purification
*Dirofilariasis/parasitology/drug therapy
*Dog Diseases/parasitology/drug therapy
*Anti-Bacterial Agents/pharmacology
*Microfilariae/drug effects/microbiology
*Molting/drug effects

@article {pmid40459768,
year = {2025},
author = {Zhang, K and Cao, J and Li, X and Zhang, ZQ},
title = {Investigating interspecific mating in the thelytokous predatory mite Amblyseius herbicolus (Chant) (Acari: Phytoseiidae), with comparative observations from three sexually reproducing phytoseiid species.},
journal = {Experimental & applied acarology},
volume = {95},
number = {1},
pages = {8},
pmid = {40459768},
issn = {1572-9702},
mesh = {Animals ; *Mites/physiology ; Male ; Female ; *Sexual Behavior, Animal ; Reproduction ; Species Specificity ; },
abstract = {Asexual reproduction can be advantageous in the short term but is generally considered an evolutionary dead end due to the lack of genetic diversity and the accumulation of deleterious mutations. The thelytokous predatory mite Amblyseius herbicolus (Chant) (Acari: Mesostigmata) shows potential for biological pest control, but its reproductive mechanism remains poorly understood. This study examined whether A. herbicolus females have retained mating ability by exposing them to morphologically similar heterospecific males from three sexually reproducing phytoseiid species: Amblydromalus limonicus (Garman & McGregor), Amblyseius lentiginosus Denmark & Schicha, and Neoseiulus cucumeris (Oudemans). No mating or insemination occurred between A. herbicolus females and heterospecific males within 24 h. In contrast, nearly all males successfully inseminated conspecific females in a follow-up observation. Mating behaviours varied across species, with A. lentiginosus showing the longest pre-mating duration and lowest insemination rate, indicating higher mate selectivity. Most Ad. limonicus males inseminated a single spermatophore, while A. lentiginosus and N. cucumeris deposited two spermatophores, suggesting differences in sperm allocation and competition. No correlation was found between male body size, mating duration, and endospermatophore volume, possibly due to the small sample size. This study does not establish whether A. herbicolus reproduces strictly through thelytoky, nor does it exclude the possibility of sexually reproducing populations elsewhere. Further research, including interspecific mating trials with the more morphologically similar Amblyseius largoensis and an investigation into the role of endosymbionts such as Wolbachia, is needed to reveal the mechanisms underlying asexuality in A. herbicolus.},
}

Animals
*Mites/physiology
Male
Female
*Sexual Behavior, Animal
Reproduction
Species Specificity

@article {pmid40454368,
year = {2025},
author = {Itokawa, K and Kuroki, A and Kobayashi, D and Kuroda, M and Sawabe, K and Isawa, H and Sanjoba, C},
title = {Genomic analysis of co-infection with Wolbachia and Candidatus Tisiphia in the sand fly Sergentomyia squamirostris.},
journal = {Frontiers in microbiology},
volume = {16},
number = {},
pages = {1577636},
pmid = {40454368},
issn = {1664-302X},
abstract = {INTRODUCTION: Endosymbiotic bacteria show diverse strategies to manipulate host reproduction for their survival in nature. The diversity of symbionts infecting hematophagous insects and their impact on host ecology could be crucial for developing effective control measures of disease-transmitting vectors. Sand flies are a group of small insects, with some species serving as vectors for leishmaniasis, bartonellosis, and arboviral diseases. Sergentomyia squamirostris is the only known species of sand flies found on the main islands of Japan. Although no medical implications exist for S. squamirostris, we conducted whole-genome sequencing to explore its potential relevance.

METHODS: We conducted whole-genome sequencing and de novo assembly of S. squamirostris using genomic DNA isolated from a single field-collected female insect sample. During this attempt, we incidentally obtained closed genomes of two new bacteria, wSSQ and RiSSQ, belonging to Wolbachia and Candidatus Tisiphia, respectively. We then investigated infection rates of both bacteria in two natural populations of S. squamirostris in Japan.

RESULTS: Phylogenetic analysis indicated that wSSQ and RiSSQ belonged to Wolbachia and Ca. Tisiphia, respectively. Ca. Tisiphia is also known as "Torix Rickettsia," which is considered a large group of endosymbionts of invertebrates with no known pathogenicity to humans and animals. NGS read depths for both wSSQ and RiSSQ genomes were found to be high coverages, indicating that these bacteria are S. squamirostris endosymbionts. The infection rates of wSSQ and RiSSQ in the wild population of S. squamirostris varied in the two different localities in Japan, and co-infection with both bacteria was commonly seen. wSSQ was detected in both sexes of S. squamirostris, whereas RiSSQ was detected only in female sand flies.

CONCLUSION: Ca. Tisiphia has recently been recognized as an underexplored endosymbiont with a widespread presence in invertebrates, including disease vectors. RiSSQ represents the first complete genomic information resource of Ca. Tisiphia infecting sand flies. Further research is needed to understand potential interactions between its host and other endosymbionts, as well as to explore the potential implications of disease control in the future.},
}

@article {pmid40452587,
year = {2025},
author = {Glass, BH and Barott, KL},
title = {Hypoxia disrupts metabolism in coral and sea anemone larvae.},
journal = {The Journal of experimental biology},
volume = {},
number = {},
pages = {},
doi = {10.1242/jeb.250372},
pmid = {40452587},
issn = {1477-9145},
support = {HD083185/NH/NIH HHS/United States ; 1923743//National Science Foundation/ ; 2237658//National Science Foundation/ ; },
abstract = {Anthropogenic pollution is driving an increase in the frequency and severity of seawater hypoxic events in coastal marine ecosystems. While hypoxia decreases physiological performance in coral and sea anemone (phylum Cnidaria) larvae, the underlying cellular mechanisms remain unexplored. Here, larvae of the reef-building corals Galaxea fascicularis and Porites astreoides and the estuarine sea anemone Nematostella vectensis were exposed to normoxia or a simulated hypoxic event (6 h at<2 mg dissolved oxygen L-1), and their metabolomic response quantified at the end of the exposure period using targeted liquid chromatography-mass spectrometry. Baseline metabolite profiles (81 amino acids, acylcarnitines, organic acids, and nucleotides) were broadly divergent between the three species, with the corals displaying a reliance on nitrogen cycling through amino acid metabolism, whereas N. vectensis relied on nucleotide metabolism. By contrast, several changes in metabolite abundances under hypoxia were shared (e.g., increases in lactate) and suggest the upregulation of glycolysis, lactic acid fermentation, and fatty acid β-oxidation as conserved mechanisms for energy production under hypoxia. Changes in these pathways were correlated with adverse physiological outcomes, including conserved declines in swimming behavior and growth. Importantly, life history traits affecting metabolism influenced hypoxia responses. For example, P. astreoides larvae, which possess algal endosymbionts, displayed the least severe metabolic response to hypoxia among these species, possibly owing to symbiont resources. Overall, these findings demonstrate that hypoxia disrupts metabolic performance in coral and sea anemone larvae through conserved and divergent pathways, emphasizing the need to limit drivers of ocean deoxygenation.},
}

@article {pmid40448476,
year = {2025},
author = {Cordaux, R and Gilbert, C},
title = {Elucidating the molecular mechanisms of sex ratio distortion mediated by cytoplasmic symbionts.},
journal = {Genome biology and evolution},
volume = {},
number = {},
pages = {},
doi = {10.1093/gbe/evaf110},
pmid = {40448476},
issn = {1759-6653},
abstract = {Endosymbionts are widespread in animals and they have deeply shaped their hosts' evolution and ecology. As they are usually maternally-inherited from one host generation to the next, a diverse array of endosymbionts (including bacteria, unicellular eukaryotes and viruses) have evolved strategies to distort host sex ratios towards females in arthropods, via male killing, parthenogenesis induction and feminization. Seminal discoveries made in the past few years have elucidated the molecular mechanisms of sex ratio distortion in various host-symbiont systems. Emerging trends suggest that: (i) a single symbiont gene is generally sufficient to mediate sex ratio distortion in a given system, (ii) causal genes are often associated with mobile elements, including prophages and plasmids, (iii) causal genes are evolutionarily diverse between systems, although they may exhibit homologous domains, and (iv) host sex-specific molecular pathways, such as sex determination and dosage compensation, are preferential targets of cytoplasmic symbiont factors. It appears that the various reproductive manipulations have evolved multiple times independently, suggesting that the recently elucidated host-symbiont systems only represent the tip of the iceberg of the high diversity of sex ratio distortion mechanisms. Capturing the breadth of these mechanisms is a desirable and arguably reachable goal that will not only lead to a better understanding of host-symbiont molecular interactions, but also has the potential to yield unprecedented insights into the molecular cascades underlying host sex determination and sexual differentiation.},
}

@article {pmid40446003,
year = {2025},
author = {Kröninger, L and Maurya, AK and Stiebeling, C and Stirba, FP and Kim, Z and Nowack, ECM},
title = {T7 RNA polymerase-based gene expression from a transcriptionally silent rDNA spacer in the endosymbiont-harboring trypanosomatid Angomonas deanei.},
journal = {PloS one},
volume = {20},
number = {5},
pages = {e0322611},
doi = {10.1371/journal.pone.0322611},
pmid = {40446003},
issn = {1932-6203},
mesh = {*DNA-Directed RNA Polymerases/genetics/metabolism ; *Symbiosis/genetics ; *Trypanosomatina/genetics ; Transcription, Genetic ; *Viral Proteins/genetics/metabolism ; *DNA, Ribosomal/genetics ; },
abstract = {Eukaryotic life has been shaped fundamentally by the integration of bacterial endosymbionts. The trypanosomatid Angomonas deanei that contains a β-proteobacterial endosymbiont, represents an emerging model to elucidate initial steps in symbiont integration. Although the repertoire of genetic tools for A. deanei is growing, no conditional gene expression system is available yet, which would be key for the functional characterization of essential or expression of toxic proteins. Development of a conditional expression system based on endogenous RNA polymerase II (POLII) is hampered by the absence of information on transcription signals in A. deanei as well as the unusual genetic system used in the Trypanosomatidae that relies on read-through transcription. This mode of transcription can result in polar effects when manipulating expression of genes in their endogenous loci. Finally, only a few resistance markers are available for A. deanei yet, restricting the number of genetic modifications that can be introduced into one strain. To increase the range of possible genetic manipulations in A. deanei, and in particular, build the base for a conditional expression system that does not interfere with the endogenous gene expression machinery, here we (i) implemented two new drug resistance markers, (ii) identified the spacer upstream of the rDNA array on chromosome 13 as transcriptionally silent genomic locus, and (iii) used this locus for engineering an ectopic expression system that depends on the T7 RNA polymerase expressed from the δ-amastin locus. We show that transgene expression in this system is independent of the activity of endogenous RNA polymerases, reaches expression levels similar to the previously described POLII-dependent expression from the γ-amastin locus, and can be applied for studying endosymbiosis. In sum, the new tools expand the possibilities for genetic manipulations of A. deanei and provide a solid base for the development of an ectopic conditional expression system.},
}

*DNA-Directed RNA Polymerases/genetics/metabolism
*Symbiosis/genetics
*Trypanosomatina/genetics
Transcription, Genetic
*Viral Proteins/genetics/metabolism
*DNA, Ribosomal/genetics

@article {pmid40442955,
year = {2025},
author = {Choi, J and Palanichamy, P and Tanaka, H and Kondo, T and Gruwell, ME and Husnik, F},
title = {Accelerated pseudogenization in the ancient endosymbionts of giant scale insects.},
journal = {Molecular biology and evolution},
volume = {},
number = {},
pages = {},
doi = {10.1093/molbev/msaf125},
pmid = {40442955},
issn = {1537-1719},
abstract = {Symbiotic microorganisms are subject to a complex interplay of environmental and population-genetic pressures that drive their gene loss. Despite the widely held perception that ancient symbionts have stable genomes, even tiny genomes experience ongoing pseudogenization. Whether these tiny genomes also experience bursts of rapid gene loss is, however, less understood. Giant scale insects (Monophlebidae) feed on plant sap and rely on the symbiotic bacterium Walczuchella, which provides them with essential nutrients. When compared to other ancient symbionts with similar genome sizes, such as Karelsulcia, Walczuchella's genome was previously reported as unusually pseudogene-rich (10 % of coding sequences). However, this result was based on only one genome assembly, raising questions about the assembly quality or a recent ecological shift such as co-symbiont acquisition driving the gene loss. Here, we generated six complete genomes of Walczuchella from three genera of giant scales, each with distinct co-symbiotic partners. We show that all the genomes are highly degraded, and particularly genes related to the cellular envelope and energy metabolism seem to be undergoing pseudogenization. Apart from general mechanisms driving genome reduction, such as the long-term intracellular lifestyle with transmission bottlenecks, we hypothesize that a more profound loss of DNA replication and repair genes, together with recent co-obligate symbiont acquisitions, likely contribute to the accelerated degradation of Walczuchella genomes. Our results highlight that even ancient symbionts with small genomes can experience significant bursts of gene loss when stochastic processes erase a gene that accelerates gene loss or when the selection pressure changes such as after co-symbiont acquisition.},
}

@article {pmid40441794,
year = {2025},
author = {Sarkar, A and Rangel, DEN and Osherov, N},
title = {Leading developments in basic research on aspergillosis and mucormycosis.},
journal = {Fungal biology},
volume = {129},
number = {4},
pages = {101574},
doi = {10.1016/j.funbio.2025.101574},
pmid = {40441794},
issn = {1878-6146},
mesh = {*Mucormycosis/microbiology/drug therapy ; Humans ; *Aspergillosis/microbiology/drug therapy ; Aspergillus fumigatus/genetics/pathogenicity/drug effects ; Rhizopus/pathogenicity/genetics ; Antifungal Agents/pharmacology ; *Biomedical Research/trends ; Virulence ; Drug Resistance, Fungal ; },
abstract = {This editorial presents an overview of notable contributions in basic research on aspergillosis and mucormycosis published between 2022 and 2024. Basic research in aspergillosis saw major advances in the field of genomics brought about by inexpensive whole-genome sequencing of hundreds of isolates. This has deepened our understanding of Aspergillus fumigatus population structure, gene diversity, and the evolution of azole antifungal resistance. Basic research in mucormycosis saw interesting developments in our understanding of the interactions between Rhizopus microsporus and endosymbiotic bacteria that protect it against predatory soil amoeba and increase its virulence in models of infection.},
}

*Mucormycosis/microbiology/drug therapy
Humans
*Aspergillosis/microbiology/drug therapy
Aspergillus fumigatus/genetics/pathogenicity/drug effects
Rhizopus/pathogenicity/genetics
Antifungal Agents/pharmacology
*Biomedical Research/trends
Virulence
Drug Resistance, Fungal

@article {pmid40435695,
year = {2025},
author = {Siddiqua, A and Mrabet, C and Boufahja, F and Abu-Elsaoud, A and Kefi-Daly Yahia, O and Daly Yahia, MN},
title = {Salinity change effects on growth and photosynthetic efficiency of the zooxanthellae Symbiodinium sp. extracted from Platygyra daedalea in Qatar coral reefs.},
journal = {Marine pollution bulletin},
volume = {218},
number = {},
pages = {118187},
doi = {10.1016/j.marpolbul.2025.118187},
pmid = {40435695},
issn = {1879-3363},
abstract = {This study investigates the impact of elevated salinity levels on the growth and photosynthetic efficiency of the coral endosymbiont Symbiodinium sp. isolated from Platygyra daedalea in the coral reefs of Qatar. Cultures were exposed to a range of salinities (30-70 psu) over a 11-day incubation period under controlled laboratory conditions. Results revealed a significant decline in cell density and growth rate at salinities above 55 psu. Photosynthetic performance, assessed using the OJIP chlorophyll fluorescence protocol, showed a marked reduction in key parameters-including ABS/RC, DIo/RC, TRo/RC, ETo/RC, Vi, Vj, Mo, and Fv/Fm-at salinities exceeding 55 psu, indicating substantial stress and inactivation of PSII reaction centers. Interestingly, a partial recovery in photosynthetic efficiency was observed at 55 and 60 psu following initial decline. This is the first study to examine the physiological response of Symbiodinium sp. to salinity stress in the Arabian Gulf, providing valuable insights for coral reef restoration initiatives in this high-salinity environment amid ongoing climate change and coastal development.},
}

@article {pmid40429177,
year = {2025},
author = {Utkuzova, AM and Chertkova, EA and Kryukova, NA and Malysh, JM and Tokarev, YS},
title = {"Hostbusters": The Bacterial Endosymbiont Wolbachia of the Parasitoid Wasp Habrobracon hebetor Improves Its Ability to Parasitize Lepidopteran Hosts.},
journal = {Insects},
volume = {16},
number = {5},
pages = {},
doi = {10.3390/insects16050464},
pmid = {40429177},
issn = {2075-4450},
support = {23-16-00262//Russian Science Foundation/ ; },
abstract = {Habrobracon hebetor is a globally acknowledged larval ectoparasitoid that is widely used to control lepidopteran pests. Wolbachia is a natural endosymbiont that regulates various aspects of the insect host biology. The ability of H. hebetor to paralyze and develop on lepidopteran larvae from five families was tested under laboratory conditions. Two lines of the wasp were used, "W+" containing a naturally occurring Wolbachia from the supergroup B, and "W-", with the endosymbiont eradicated by antibiotic treatment, followed by propagation of 20 subsequent generations. The proportions of larvae in which host paralysis, as well as parasitoid oviposition, larval, pupal, and adult development were observed, were usually higher in W+ compared to W-. In Loxostege sticticalis, differences in these indices were not statistically significant. In Galleria mellonella, Mamestra brassicae, and Ostrinia nubilalis, some of the parasitism indices were significantly higher in W+ than in W-. In Bombyx mori and Plutella xylostella, H. hebetor could not complete its life cycle, but parasitism levels at the initial steps (from paralysis symptoms to the presence of larvae/pupae of the parasitoid) were 2-5 times lower in W- compared to W+ (p < 0.01). It can be suggested that the presence of Wolbachia is advantageous for H. hebetor, as it increases the success of parasitism in a broad range of lepidopteran hosts.},
}

@article {pmid40421697,
year = {2025},
author = {Shen, Y and He, J and Ma, Y and Song, X and Li, P and Zhang, C and Zhou, Z and Chen, R},
title = {MtPEPC2 Encodes a Phosphoenolpyruvate Carboxylase Essential for Symbiotic Nitrogen Fixation in Medicago truncatula.},
journal = {Plant, cell & environment},
volume = {},
number = {},
pages = {},
doi = {10.1111/pce.15636},
pmid = {40421697},
issn = {1365-3040},
support = {//This study was supported by grants from the National Key Research and Development Program of China (2022YFF1003200; R.C.), National Natural Science Foundation of China (32270261; R.C.) Strategic Priority Research Program of Chinese Academy of Sciences (XDA26030103; R.C.) and Science and Technology Department of Gansu Province, China (22ZD6NA049; R.C.)./ ; },
abstract = {Symbiotic nitrogen fixation (SNF) that takes place in root nodules of legumes essentially relies on the exchange of nitrogen (N) and carbon (C) metabolites between the symbiotic partners. The endosymbionts rhizobia provide ammonium to the host plants, and in return receive carbon and energy sources from the host for nitrogen fixation. In a forward genetic study, we identified FN6516 as an SNF-defective (fix[-]) mutant of Medicago truncatula. Whole genome resequencing, genetic linkage analysis of an F2 segregating population, genetic complementation and gene editing results show that a plant-type PEPC, MtPEPC2, is the candidate gene. We demonstrate that MtPEPC2 expression is activated in nodules and that a high level of expression is detected at an early stage of nodule development. MtPEPC2 protein is localised in the cytoplasm of both infected and uninfected cells, but not in symbiosomes. Our work shows that a nonsense mutation in MtPEPC2 resulted in a great reduction in PEPC activities, almost complete loss of nodule nitrogen fixation activities, and defects in differentiation and/or maintenance of bacteroids. Importantly, overexpression of MtPEPC2 increased nodule nitrogenase activities.},
}

@article {pmid40417250,
year = {2025},
author = {Obert, T and Zhang, T and Rurik, I and Vďačný, P},
title = {Rediscovery and morpho-molecular characterization of three astome ciliates, with new insights into eco-evolutionary associations of astomes with their annelid hosts.},
journal = {Marine life science & technology},
volume = {7},
number = {2},
pages = {231-255},
pmid = {40417250},
issn = {2662-1746},
abstract = {UNLABELLED: Astome ciliates live in the digestive tract of a broad spectrum of marine, freshwater, and terricolous annelids. In aquatic lumbriculid and criodrilid oligochaetes collected in Central Europe, we rediscovered three insufficiently known astomes: Hoplitophrya secans, Mesnilella clavata, and Buchneriella criodrili. Their morphology was studied using in vivo observation, protargol, and dry silver nitrate impregnation. Multiple nuclear and mitochondrial molecular markers were used to determine their phylogenetic positions and reconstruct their evolutionary history. According to our phylogenetic analyses: (1) mouthless ciliates isolated from annelids form a robustly supported monophylum within the class Oligohymenophorea, (2) the progenitor of astomes invaded the digestive tract of marine polychaetes during the Paleozoic era, (3) lumbricid earthworms likely served as a source of astomes for criodrilid, almid, and megascolecid earthworms, (4) the ancestral host of the earthworm-dwelling astome clade led an endogeic lifestyle, and (5) there were multiple independent transfers of astomes from endogeic to epigeic and anecic earthworms. These findings support previous views of the annelid phylogeny, suggesting that astomes reside and evolve in tandem with annelids for several hundred million years.

SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s42995-024-00275-5.},
}

@article {pmid40413780,
year = {2025},
author = {Gu, X and Berran, M and Prithiv Sivaji Dorai, A and Yang, Q and Stelmach, M and Ross, PA and Gill, A and Ansermin, E and Yeatman, E and Umina, PA and Hoffmann, AA},
title = {Transinfections of the endosymbiont Rickettsiella viridis in different Myzus persicae (Hemiptera: Aphididae) clones show consistent deleterious effects and stable transmission.},
journal = {Journal of economic entomology},
volume = {},
number = {},
pages = {},
doi = {10.1093/jee/toaf114},
pmid = {40413780},
issn = {1938-291X},
abstract = {Endosymbionts are widespread in insects, including aphids, and can have multiple effects on insect host fitness, suggesting potential applications for endosymbiont-related pest control. A transinfection of the endosymbiont Rickettsiella viridis into a line of the novel host Myzus persicae has previously shown large deleterious effects on aphid fitness and rapid spread in caged aphid populations under a cool environment. Because host clones can significantly influence endosymbiont effects and fitness-related traits more generally, it is important to test endosymbiont effects across a range of genotypic backgrounds. Here, we developed four Rickettsiella transinfected lines in different M. persicae clones via hemolymph microinjection, including clones with relatively high pesticide resistance. All four lines exhibited consistent fitness costs, reflected in reductions in both fecundity and longevity and reduced heat tolerance, although the magnitude of these effects varied among clones. The lines also resulted in stable and similar shifts in body color, with infected aphids being darker in color, although clonal effects were again observed. Vertical transmission was stable in all clones, and Rickettsiella infection was also shown to be transmitted horizontally between aphid pairs within Petri dishes in each clone. These results demonstrate consistent transmission and deleterious fitness effects of Rickettsiella transinfections, while also highlighting genetic background effects.},
}

@article {pmid40411150,
year = {2025},
author = {Ayoubi, A and Talebi, AA and Fathipour, Y and Hoffmann, AA and Mehrabadi, M},
title = {Symbiont-mediated insect host defense against parasitism: insights from the endosymbiont, Hamiltonella defensa and the insect host, Myzus persicae.},
journal = {Pest management science},
volume = {},
number = {},
pages = {},
doi = {10.1002/ps.8844},
pmid = {40411150},
issn = {1526-4998},
abstract = {BACKGROUND: Sap-feeding insects like aphids can harbor a complex of bacterial symbionts, including a primary nutritional symbiont and secondary symbionts that may influence various traits such as resistance to parasitoids and entomopathogens as well as fitness. This study explores the presence and impact of the facultative symbiont, Hamiltonella defensa, in a major pest aphid, the green peach aphid Myzus persicae, focusing particularly on its role in aphid parasitoid resistance, an area that has not been previously characterized.

RESULTS: We detected Buchnera aphidicola and H. defensa endosymbionts in a population of M. persicae collected from Tehran, Iran. Using antibiotic treatments, we mostly removed H. defensa from the aphid and generated a line with only a low level of the symbiont. The parasitism rate of Aphidius matricariae significantly increased in this line compared to untreated controls. Quantitative polymerase chain reaction (qPCR) analysis indicated that the densities of B. aphidicola and H. defensa were affected following parasitism. Twenty-four hours after parasitism, the density of H. defensa and its phage (APSE, Acyrthosiphon pisum secondary endosymbiont) increased compared to the controls, while the density of B. aphidicola decreased. Reverse transcription PCR (RT-qPCR) of APSE encoding toxins revealed high transcription levels of the YDp toxin at 24 h post-parasitism.

CONCLUSION: These findings indicate that the APSE-3 bacteriophage is present in H. defensa from M. persicae and likely confers parasitoid resistance in this aphid through the YDp toxin. Overall, these results suggest that Hamiltonella can partly protect M. persicae against parasitism. The results have implications for biological control programs targeting this major insect pest. © 2025 Society of Chemical Industry.},
}

@article {pmid40401914,
year = {2025},
author = {Parry, ERS and Pevsner, R and Poulton, BC and Purusothaman, D-K and Adam, AI and Issiaka, S and Ant, TH and Rainey, SM and Bilgo, E and Diabaté, A and Sinkins, SP},
title = {Imaging the lifecycle of Microsporidia sp. MB in Anopheles coluzzii from western Burkina Faso reveals octosporogony.},
journal = {mSphere},
volume = {},
number = {},
pages = {e0085124},
doi = {10.1128/msphere.00851-24},
pmid = {40401914},
issn = {2379-5042},
abstract = {UNLABELLED: A newly discovered microsporidian, Microsporidia sp. MB (MB), was recently found to block Plasmodium falciparum transmission in Anopheles arabiensis mosquitoes from Kenya. Here, we describe the lifecycle of the first laboratory colony of Anopheles coluzzii with MB, originating from western Burkina Faso. The lifecycle of MB was explored using fluorescent in situ hybridization and confocal microscopy, facilitated by the development of optimized protocols to produce histological sections of whole adult, larval, and embryo tissues. As in An. arabiensis, transmission appears to be predominantly vertical, with MB highly localized to the ovaries across multiple lifecycle stages. MB was sparsely distributed within the majority of developing oocytes in the gravid female. After oviposition, in the majority of embryos, MB relocated to the developing gonad at the onset of tissue differentiation, suggesting a highly specialized adaptation to host tissues. Sporogony was identified for the first time in a proportion of developing oocytes and in embryos post-oviposition. Microsporidian spore characteristics were subsequently confirmed with electron microscopy. Identification of MB sporogony in eggs suggests there are alternative horizontal routes of transmission which could play an important role in developing MB as a malaria control strategy.

IMPORTANCE: Malaria in West Africa, caused by Plasmodium falciparum infection and spread by anopheline mosquitoes, is responsible for hundreds of thousands of deaths annually and resulted in over 120 million cases in 2022 . The transmission-blocking effect of Microsporidia sp. MB (MB) suggests its potential as an agent for combating the spread of malaria. Understanding the routes of transmission and their effect on MB in mosquito populations is crucial for its development as a control tool. The identification of MB spores reveals the potential for another avenue of transmission beyond the vertical transmission from female to offspring. Spores could also have the potential for alternative MB dissemination methods, alongside or instead of adult mosquito releases.},
}

@article {pmid40401706,
year = {2025},
author = {Brenninger, FA and Zug, R and Kokko, H},
title = {Infection dynamics of endosymbionts that manipulate arthropod reproduction.},
journal = {Biological reviews of the Cambridge Philosophical Society},
volume = {},
number = {},
pages = {},
doi = {10.1111/brv.70024},
pmid = {40401706},
issn = {1469-185X},
support = {//Universität Zürich/ ; //Alexander von Humboldt Foundation/ ; //Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung/ ; },
abstract = {A large proportion of arthropod species are infected with endosymbionts, some of which selfishly alter host reproduction. The currently known forms of parasitic reproductive manipulations are male-killing, feminization, cytoplasmic incompatibility, parthenogenesis induction and distortion of sex allocation. While all of these phenomena represent adaptations that enhance parasite spread, they differ in the mechanisms involved and the consequent infection dynamics. We focus here on the latter aspect, summarizing existing theoretical literature on infection dynamics of all known reproductive manipulation types, and completing the remaining knowledge gaps where dynamics have not been modelled yet. Our unified framework includes the minimal model components required to describe the effects of each manipulation. We establish invasion criteria for all potential combinations of manipulative endosymbionts, yielding predictions for an endosymbiont's increase from rarity within a host population that is initially either uninfected or infected with a different symbiont strain. We consider diplodiploid and haplodiploid hosts, as the mechanisms as well as the infection dynamics of reproductive manipulations can differ between them. Our framework reveals that endosymbionts that a priori have the best invasion prospects are not necessarily the most commonly found ones in nature; priority effects play a role too, and cytoplasmic incompatibility excels in this regard. As a whole, considerations of the ease with which a symbiont spreads have to be complemented with knowledge of how easy it is to achieve a particular manipulation, and with factors influencing the probability that interspecific host switching occurs and succeeds.},
}

@article {pmid40400517,
year = {2025},
author = {Ohata, Y and Sugimoto, TN and Wybouw, N and Tagami, Y},
title = {Suppression of cytoplasmic incompatibility in the leaf-mining fly Liriomyza sativae with a nuclear Wolbachia insert.},
journal = {Royal Society open science},
volume = {12},
number = {5},
pages = {242137},
pmid = {40400517},
issn = {2054-5703},
abstract = {Cytoplasmic incompatibility (CI) drives maternally transmitted endosymbionts such as Wolbachia through insect populations by inducing embryonic mortality when infected males fertilize uninfected females. CI is controlled by Wolbachia cif operons that are categorized into multiple phylogenetic types. CI strength is further shaped by poorly understood host factors, including development and genetic background. To study the strength of CI across different host species, we genotyped a Japanese field population of Liriomyza sativae. By uncovering paternal transmission of Wolbachia genic elements, we collected strong evidence of horizontal genome transfer, including Type I and Type V cif operons, from Wolbachia into the nuclear genome of L. sativae. We established a transinfection of wLtri in L. sativae, a Wolbachia variant that induces strong CI in Liriomyza trifolii. No CI was observed in both intraspecific and interspecific reciprocal crosses with L. trifolii, suggesting that both uninfected females and infected males of L. sativae completely suppress wLtri-mediated CI. Our results raise the appealing hypothesis that host suppression of Wolbachia-induced CI might evolve owing to horizontal transfer of cif operons into the host nuclear genome.},
}

@article {pmid40399396,
year = {2025},
author = {Avesani, A and Auguste, M and Doni, L and Oliveri, C and Azzola, A and Bosi, E and Montefalcone, M and Vezzulli, L},
title = {First insights into bacterial and microalgal endosymbiont communities of various coral morphotypes from Maldives.},
journal = {Scientific reports},
volume = {15},
number = {1},
pages = {17577},
pmid = {40399396},
issn = {2045-2322},
support = {CUP D33C22000960007//National Recovery and Resilience Plan (NRRP)/ ; },
mesh = {*Anthozoa/microbiology ; Animals ; *Symbiosis ; RNA, Ribosomal, 16S/genetics ; *Bacteria/genetics/classification/isolation & purification ; *Microbiota/genetics ; Coral Reefs ; *Microalgae/genetics/physiology/classification ; Phylogeny ; Biodiversity ; Seawater/microbiology ; Indian Ocean Islands ; Maldives ; },
abstract = {The Maldivian Archipelago is home to valuable coral reefs that have been extensively studied for their ecological diversity. However, the diversity of the microbiome in Maldivian corals remains largely unexplored. In this study, the microbiota compositions (including both algal endosymbionts and bacteria) were investigated for the first time across various coral morphotypes sampled in May 2022 from four Maldivian atolls (Ari, North Malé, South Malé, and Rasdhoo). Coral and gorgonian specimens were collected via scuba diving at reef sites located on both ocean-exposed reefs and lagoon sites, across various depths (0-40 m). Surface seawater samples were also collected near coral assemblages. Metabarcoding analyses were performed, targeting the 16S rRNA gene to assess bacterial composition, and the Internal Transcribed Spacer 2 (ITS2) rRNA region to evaluate microalgal endosymbiont diversity. Generally, the bacterial communities associated with corals exhibited significant diversity, which was primarily influenced by coral morphotype rather than depth or geographic location. These communities were also markedly different when compared to those found in seawater. The three most abundant bacterial taxa in coral samples were Proteobacteria (ranging from 10 to 95%), Bacillota (formerly known as Firmicutes, ranging from 5 to 10%), and Planctomycetota (ranging from < 1-30%). Most Symbiodiniaceae belonged to the genera Cladocopium-C and Durusdinium-D (> 90%), while host specificity was observed for variant types. Overall, this study provides first insights into the structure of Maldivian coral microbiota, which could be crucial for monitoring the health of local coral populations and predicting the potential impacts of changing environmental conditions in the region.},
}

*Anthozoa/microbiology
Animals
*Symbiosis
RNA, Ribosomal, 16S/genetics
*Bacteria/genetics/classification/isolation & purification
*Microbiota/genetics
Coral Reefs
*Microalgae/genetics/physiology/classification
Phylogeny
Biodiversity
Seawater/microbiology
Indian Ocean Islands
Maldives

@article {pmid40396002,
year = {2022},
author = {Strunov, A and Schmidt, K and Kapun, M and Miller, WJ},
title = {Autophagy regulates endosymbiont distribution in early Drosophila embryogenesis.},
journal = {Autophagy reports},
volume = {1},
number = {1},
pages = {373-376},
pmid = {40396002},
issn = {2769-4127},
}

@article {pmid40394207,
year = {2025},
author = {Ackermann, RE and Gall, CA and Brayton, KA and Collins, NE and van Wyk, I and Wentzel, J and Kolo, AO and Oosthuizen, MC},
title = {Temporal changes in the bacterial microbiome of the salivary gland and midgut tissues of Rhipicephalus sanguineus (s.l.) ticks in South Africa.},
journal = {Scientific reports},
volume = {15},
number = {1},
pages = {17434},
pmid = {40394207},
issn = {2045-2322},
support = {92739//South African National Research Foundation/ ; R01AI136832//National Institute of Allergy and Infectious Diseases of the National Institutes of Health/ ; },
abstract = {Tick-borne bacterial pathogens from animals play a significant role in the (re)emergence of human diseases. Rhipicephalus sanguineus sensu lato, a globally prevalent tick, predominantly parasitises domestic dogs but can also feed on humans. We characterised temporal changes in the bacterial microbiome of the midgut and salivary gland tissues of R. sanguineus s.l. ticks and analysed their potential as reservoirs for pathogenic bacteria. A 16 S microbiome and amplicon sequence variant (ASV) approach was used to study the bacteria present in the tissues of R. sanguineus s.l. ticks collected from dogs in Hluvukani, a village in a rural community in Bushbuckridge, Mpumalanga, South Africa, in 2016, 2017 and 2019. Post processing, we obtained 43,161 total sequence reads which were clustered into ASVs by sample year. The final ASVs dataset consisted of seven genera: Coxiella, Anaplasma, Escherichia/Shigella, Ehrlichia, Borrelia, Rickettsia and Wolbachia. No differences in the microbiome profiles of the MG and SG tissues were noted. Coxiella endosymbionts dominated the microbiome in all years. Anaplasma was first detected in 2017, and an increase in Anaplasma levels was detected in 2019, when compared to 2017. All other genera were present at low levels. With the exclusion of Wolbachia, the other detected genera could have pathogenic potential, highlighting the role that R. sanguineus s.l. might play as a reservoir of pathogens.},
}

@article {pmid40391904,
year = {2025},
author = {Gasser, MT and Flatau, R and Altamia, MA and Filone, CM and Distel, DL},
title = {Complete genome sequences of two shipworm endosymbiont strains, Teredinibacter turnerae SR01903 and SR02026.},
journal = {Microbiology resource announcements},
volume = {},
number = {},
pages = {e0026525},
doi = {10.1128/mra.00265-25},
pmid = {40391904},
issn = {2576-098X},
abstract = {We present the complete genome sequences of two strains of Teredinibacter turnerae, SR01903 and SR02026, shipworm endosymbionts isolated from the gills of Lyrodus pedicellatus and Teredo bartschi, respectively, and derived from Oxford Nanopore sequencing. These sequences will aid in the comparative genomics of shipworm endosymbionts and symbiosis model development.},
}

@article {pmid40378046,
year = {2025},
author = {Cai, T and Wan, H},
title = {Protocol for isolating, culturing, and artificially infecting the Arsenophonus endosymbiont of Nilaparvata lugens.},
journal = {STAR protocols},
volume = {6},
number = {2},
pages = {103833},
doi = {10.1016/j.xpro.2025.103833},
pmid = {40378046},
issn = {2666-1667},
abstract = {Endosymbionts play a crucial role in insect physiology and adaptation. Here, we present a protocol for isolation, cultivation, and artificial infection of the Arsenophonus endosymbiont of Nilaparvata lugens. We describe steps for symbiont isolation, in vitro culture maintenance, genetic modification, and host reinfection. This protocol enables controlled studies of symbiont-host interactions and provides a foundation for symbiont-based pest management strategies. For complete details on the use and execution of this protocol, please refer to Cai et al.[1].},
}

@article {pmid40370212,
year = {2025},
author = {Tekle, YI and Smith, AR and McGinnis, M and Ghebezadik, S and Patel, P},
title = {A New Paramoeba Isolate From Florida Exhibits a Microtubule-Bound Endosymbiont Closely Associated With the Host Nucleus.},
journal = {The Journal of eukaryotic microbiology},
volume = {72},
number = {3},
pages = {e70011},
doi = {10.1111/jeu.70011},
pmid = {40370212},
issn = {1550-7408},
support = {2401946//National Science Foundation/ ; 1R15GM116103-02/NH/NIH HHS/United States ; SFA-23-5//Simons Fellow Award/ ; },
mesh = {*Symbiosis ; Phylogeny ; Animals ; Florida ; *Microtubules ; RNA, Ribosomal, 18S/genetics ; DNA, Protozoan/genetics ; },
abstract = {The genera Paramoeba and Neoparamoeba, within the family Paramoebidae (order Dactylopodida), are distinguished by their dactylopodial pseudopodia and the presence of an intracellular eukaryotic symbiont, the Perkinsela-like organism (PLO). Taxonomic classification within these genera has been challenging due to overlapping morphological traits and close phylogenetic relationships. They are marine, with some playing significant roles as parasites. Notably, they have been implicated in sea urchin mass mortality events and are known causative agents of Amoebic Gill Disease (AGD) in fish. Despite their ecological and economic importance, many aspects of their diversity, biology, evolution, and host interactions remain poorly understood. In this study, we describe a novel amoeba species, Paramoeba daytoni n. sp., isolated from Daytona Beach, Florida. Morphological and molecular analyses confirm its placement within the Paramoeba clade, closely related to P. eilhardi, P. karteshi, and P. aparasomata. Phylogenetic assessments using 18S rDNA (18S) and Cytochrome c Oxidase I (COI) markers demonstrate the limitations of the 18S gene for species delineation, highlighting COI as a more reliable genetic marker for this group. Additionally, observations on PLO morphology, movement, and microtubule association provide insights into the endosymbiotic relationship, reinforcing the need for further research into this unique eukaryote-eukaryote symbiosis.},
}

*Symbiosis
Phylogeny
Animals
Florida
*Microtubules
RNA, Ribosomal, 18S/genetics
DNA, Protozoan/genetics

@article {pmid40369879,
year = {2025},
author = {Lu, D and Grant, M and Lim, BL},
title = {NAD(H) and NADP(H) in Plants and Mammals.},
journal = {Molecular plant},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.molp.2025.05.004},
pmid = {40369879},
issn = {1752-9867},
abstract = {Nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP) are essential metabolic coenzymes in prokaryotic and eukaryotic cells, with their reduced forms, NAD(P)H, serving as electron donors for myriad reactions. NADH is mainly involved in catabolic reactions, whereas NADPH is mainly involved in anabolic and antioxidative reactions. The presence of endosymbiont-derived organelles in eukaryotes has made the functional division of NADH and NADPH systems more complex. Chloroplasts in photoautotrophic eukaryotes provide additional sources of reductants, complicating the maintenance of the redox balance of NAD(P)[+]/NAD(P)H compared with heterotrophic eukaryotes. In this review, we discuss the two redox systems in plants and systematically compare them with those in mammals, including the similarities and differences in the biosynthesis and subcellular transport of NAD[+], the biosynthesis of NADP[+], and the metabolic reactions for the reduction and oxidation of NAD(P)H. We also describe the regulation of pyridine nucleotide pools and their ratios in different plant subcellular compartments and the effects of light on these ratios. We discuss the advantages of having both NADH and NADPH systems, highlight current gaps in our understanding of NAD(P)H metabolism, and propose research approaches that could fill in those gaps. This knowledge could be used to guide bioengineering strategies to optimize redox processes and improve energy use efficiency in crop plants.},
}

@article {pmid40366182,
year = {2025},
author = {Martin Říhová, J and Vodička, R and Hypša, V},
title = {An obligate symbiont of Haematomyzus elephantis with a strongly reduced genome resembles symbiotic bacteria in sucking lice.},
journal = {Applied and environmental microbiology},
volume = {},
number = {},
pages = {e0022025},
doi = {10.1128/aem.00220-25},
pmid = {40366182},
issn = {1098-5336},
abstract = {The parvorder Rhynchophthirina with a single genus Haematomyzus is a small group of ectoparasites of unclear phylogenetic position, related to sucking and chewing lice. Previous screening based on the 16S rRNA gene indicated that Haematomyzus harbors a symbiotic bacterium whose DNA exhibits a strong shift in nucleotide composition typical of obligate mutualistic symbionts in insects. Within Phthiraptera, the smallest known genomes are found in the symbionts associated with sucking lice, which feed exclusively on mammal blood, compared to the generally larger genomes of the symbionts inhabiting chewing lice, which feed on skin derivatives. In this study, we investigate the genome characteristics of the symbiont associated with Haematomyzus elephantis. We sequenced and assembled the H. elephantis metagenome, extracted a genome draft of its symbiotic bacterium, and showed that the symbiont has a significantly reduced genome, which is with 0.39 Mbp the smallest genome among the symbionts known from Phthiraptera. Multigenic phylogenetic analysis places the symbiont into one of three clusters composed of long-branched symbionts from other insects. More specifically, it clusters together with symbionts from several other sucking lice and also with Wigglesworthia glossinidia, an obligate symbiont of tsetse flies. Consistent with the dramatic reduction of its genome, the H. elephantis symbiont lost many metabolic capacities. However, it retained functional pathways for four B vitamins, a trait typical for symbionts in blood-feeding insects. Considering genomic, metabolic, and phylogenetic characteristics, the new symbiont closely resembles those known from several sucking lice rather than chewing lice.IMPORTANCERhynchophthirina is a unique small group of permanent ectoparasites that is closely related to both sucking and chewing lice. These two groups of lice differ in their morphology, ecology, and feeding strategies. As a consequence of their different dietary sources, i.e., mammals' blood vs vertebrate skin derivatives, they also exhibit distinct patterns of symbiosis with obligate bacterial symbionts. While Rhynchophthirina shares certain traits with sucking and chewing lice, the nature of its obligate symbiotic bacterium and its metabolic role is not known. In this study, we assemble the genome of symbiotic bacterium from Haematomyzus elephantis (Rhynchophthirina), demonstrating its close similarity and phylogenetic proximity to several symbionts of sucking lice. The genome is highly reduced (representing the smallest genome among louse-associated symbionts) and exhibits a significant loss of metabolic pathways. However, similar to other sucking louse symbionts, it retains essential pathways for the synthesis of several B vitamins.},
}

@article {pmid40351112,
year = {2025},
author = {Chang, CY and Zhao, YN and Guo, HF and Liu, XD},
title = {Food nutrition and facultative endosymbiont modulate dietary breadth of a polyphagous aphid.},
journal = {Insect science},
volume = {},
number = {},
pages = {},
doi = {10.1111/1744-7917.70069},
pmid = {40351112},
issn = {1744-7917},
support = {CX23(1037)//Jiangsu Agricultural Science and Technology Innovation Fund/ ; 31672034//National Natural Science Foundation of China/ ; },
abstract = {While host plants and endosymbionts have been implicated in influencing dietary breadth in polyphagous herbivores, the underlying mechanism remains vague. In this study, we focused on the food nutrition and nutrition provision of endosymbionts to elucidate the determination of dietary breadth in a polyphagous aphid Aphis gossypii. Our findings demonstrated that high sugar and riboflavin presence in food decreased aphid fitness, while Arsenophonus infections improved aphid performance. Aphids collected from cotton could not use cucumber whether they were infected with Arsenophonus or not, signifying a distinct specialization toward cotton. Further, both the Arsenophonus-infected and free aphids fed on artificial diet varying in sugar titer failed to utilize cucumber. However, Arsenophonus-free aphids attained the ability to utilize cucumber after feeding on the riboflavin-free diet, but not on the riboflavin-containing diet, indicating riboflavin and Arsenophonus-absent expansion in dietary breadth. Notably, up-regulated expression of riboflavin synthase genes of the obligated symbiont Buchnera aphidicola was detected in the Arsenophonus-infected aphids which may provide more riboflavin. Arsenophonus promoting riboflavin synthesis in the obligated symbiont B. aphidicola and riboflavin ingestion enhancing host specialization of aphids to cotton modulate dietary breadth of A. gossypii.},
}

@article {pmid40347137,
year = {2025},
author = {Kanai, Y and Shibai, A and Yokoi, N and Tsuru, S and Furusawa, C},
title = {Laboratory evolution of the bacterial genome structure through insertion sequence activation.},
journal = {Nucleic acids research},
volume = {53},
number = {9},
pages = {},
doi = {10.1093/nar/gkaf331},
pmid = {40347137},
issn = {1362-4962},
support = {21J20693//Japan Society for the Promotion of Science/ ; JPMJER1902//Japan Science and Technology Agency/ ; JP223fa627001//Japan Agency for Medical Research and Development/ ; G-2025-2-046//Institute for Fermentation, Osaka/ ; },
mesh = {*Genome, Bacterial ; *DNA Transposable Elements/genetics ; *Escherichia coli/genetics ; *Evolution, Molecular ; Genome Size ; *Directed Molecular Evolution ; *Mutagenesis, Insertional ; },
abstract = {The genome structure fundamentally shapes bacterial physiology, ecology, and evolution. Though insertion sequences (IS) are known drivers of drastic evolutionary changes in the genome structure, the process is typically slow and challenging to observe in the laboratory. Here, we developed a system to accelerate IS-mediated genome structure evolution by introducing multiple copies of a high-activity IS in Escherichia coli. We evolved the bacteria under relaxed neutral conditions, simulating those leading to IS expansion in host-restricted endosymbionts and pathogens. Strains accumulated a median of 24.5 IS insertions and underwent over 5% genome size changes within ten weeks, comparable to decades-long evolution in wild-type strains. The detected interplay of frequent small deletions and rare large duplications updates the view of genome reduction under relaxed selection from a simple consequence of the deletion bias to a nuanced picture including transient expansions. The high IS activity resulted in structural variants of IS and the emergence of composite transposons, illuminating potential evolutionary pathways for ISs and composite transposons. The extensive genome rearrangements we observed establish a baseline for assessing the fitness effects of IS insertions, genome size changes, and rearrangements, advancing our understanding of how mobile elements shape bacterial genomes.},
}

*Genome, Bacterial
*DNA Transposable Elements/genetics
*Escherichia coli/genetics
*Evolution, Molecular
Genome Size
*Directed Molecular Evolution
*Mutagenesis, Insertional

@article {pmid40334664,
year = {2025},
author = {Sandin, MM and Renaudie, J and Suzuki, N and Not, F},
title = {Extant diversity, biogeography, and evolutionary history of Radiolaria.},
journal = {Current biology : CB},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.cub.2025.04.032},
pmid = {40334664},
issn = {1879-0445},
abstract = {Since Ernst Haeckel and the Challenger expedition (1872-1876), Radiolaria have been known as ubiquitous and abundant star-shaped oceanic plankton. Their exquisite biomineralized skeletons left an extensive fossil record extremely valuable for biostratigraphic and paleo-environmental research. In contemporary oceans, there is growing evidence that Radiolaria are significant contributors to marine food webs and global biogeochemical cycles. Here we provide a comprehensive morpho-molecular framework to assess the extant diversity, biogeography, and evolutionary history of Radiolaria. Our analyses reveal that half of radiolarian diversity is morphologically undescribed, with a large part forming three hyper-diverse environmental clades, named Rad-A, Rad-B, and Rad-C. We suggest that most of this undescribed diversity comprises skeleton-less life forms or endosymbionts, explaining their elusive, yet abundant, nature. Phylogenetic analyses highlight the need for a major revision of high-level Radiolaria taxonomy, including placement of Collodaria within the order Nassellaria. Global metabarcoding surveys show that Radiolaria contributes more than 12% to the total eukaryotic community, displaying distinct biogeographic patterns with the skeleton-less lineages at depth and photosymbiont-bearing lineages in the surface. Fossil calibration of a molecular clock revealed the first appearance of Radiolaria ∼760 million years ago (mya), the development of the skeleton in the early Paleozoic (∼500 mya), and the onset of photosymbiotic relationships during the mid to late Mesozoic (∼140 mya), related to geological periods of oligotrophy and anoxia. The results presented here provide a robust framework for developing new perspectives on early eukaryotic diversification, paleo-environmental impacts on plankton evolution, and marine microbial ecology in rapidly evolving ecosystems.},
}

@article {pmid40332947,
year = {2025},
author = {Csorba, AB and Szanyi, K and Szanyi, S and Tarcali, G and Balog, A and Nagy, A},
title = {Pre-Crop Chemical Control Has No Effects on Corn Leaf Aphid, Rhopalosiphum maidis (Fitch) (Hemiptera: Aphididae) Endosymbiotic Bacterial Diversity Along an Industrial Maize Management.},
journal = {Insects},
volume = {16},
number = {4},
pages = {},
doi = {10.3390/insects16040417},
pmid = {40332947},
issn = {2075-4450},
support = {2024//University of Debrecen Scientific Research Bridging Fund (DETKA)/ ; },
abstract = {During this research, the corn leaf aphids endosymbiotic bacterial diversity was tested in the same crop systems (monoculture industrial maize as grain for livestock) and the same soil type (Chernozem) when pre-crop pesticide management was used. Bacterial symbionts were analyzed using Illumina systems, and the Silva 16S NR99 V138.2 database was used to assign bacterial taxa on genus and species levels. The presence of the obligate endosymbiont B. aphidicola has been clearly detected in all cases, and in all samples but its abundance varied between samples inside crops, but not between crops and generations. The facultative symbionts S. symbiotica and Wolbachia spp. frequency varied between generations, and increased at generation II; however, differences were not significant. We concluded that the pre-crop pesticide application has no effect on corn leaf aphids bacterial symbionts, so the indirect pesticide application on aphids adaptation is low or nonexistent.},
}

@article {pmid40332799,
year = {2025},
author = {Bai, C and Duan, Y and Zhao, C and Yan, L and Suthisut, D and Lü, J and Bai, Y and Zeng, F and Zhang, M},
title = {Abundance of the Dominant Endosymbiont Rickettsia and Fitness of the Stored-Product Pest Liposcelis bostrychophila (Psocoptera: Liposcelididae).},
journal = {Insects},
volume = {16},
number = {4},
pages = {},
doi = {10.3390/insects16040349},
pmid = {40332799},
issn = {2075-4450},
support = {32172260//National Natural Science Foundation of China/ ; },
abstract = {Endosymbiotic bacteria are key factors that regulate the biological traits of Liposcelis bostrychophila. This study employed metagenomic methods to analyze the dominant species of symbiotic microorganisms associated with L. bostrychophila. By controlling the environmental temperature, we were able to manipulate the abundance of endosymbionts and establish populations with high, medium, and low levels of these bacteria. This allowed us to examine the fitness parameters of L. bostrychophila under different levels of endosymbiont abundance. The experimental results revealed that L. bostrychophila hosts 51 genera of symbiotic microorganisms, with Rickettsia being the dominant genus, accounting for 84.11% to 98.16% of the total share. Environmental temperature significantly affected the abundance of Rickettsia, with notable differences observed during the adult stage of L. bostrychophila. A temperature gradient of 28 °C, 35 °C, and 37 °C was established, allowing for the classification of populations based on Rickettsia abundance into three categories: high-abundance populations (LBhp), medium-abundance populations (LBmp), and low-abundance populations (LBlp). The abundance of Rickettsia had a significant impact on the fitness of L. bostrychophila. Specifically, a high abundance of Rickettsia contributed positively to population fitness by increasing egg production, prolonging egg hatching time, enhancing lifespan, and improving both survival and reproductive rates. Therefore, the endosymbiont Rickettsia plays a crucial role in the growth and development of L. bostrychophila. In the future, our research will help further uncover the interactions between Rickettsia and its host, providing new perspectives for pest control and offering a better understanding of insect biology and ecology.},
}

@article {pmid40196488,
year = {2025},
author = {Lindsey, AR and Lue, CH and Davis, JS and Borjon, LJ and Mauthner, SE and Fricke, LC and Eads, L and Murphy, M and Drown, MK and Faulk, C and Buffington, ML and Tracey, WD},
title = {Genomics and reproductive biology of Leptopilina n. sp. Buffington, Lue, Davis & Tracey sp. nov. (Hymenoptera: Figitidae): An asexual parasitoid of Caribbean Drosophila.},
journal = {bioRxiv : the preprint server for biology},
volume = {},
number = {},
pages = {},
doi = {10.1101/2025.03.28.645512},
pmid = {40196488},
issn = {2692-8205},
abstract = {Drosophila and parasitic wasps in the genus Leptopilina have long been a model for understanding host-parasite interactions. Indeed, parasitic wasps are important drivers of ecological and evolutionary processes broadly, but we are generally lacking information about the diversity, natural history, and evolution of these relationships. We collected insects from the Caribbean Island of Saint Lucia, home to the eastern Caribbean ' dunni ' subgroup of Drosophila : a clade long appreciated for its recent patterns of speciation and adaptation. Here we present an integrative approach that incorporates natural history, taxonomy, physiology, and genomics to describe Leptopilina n. sp. Buffington, Lue, Davis & Tracey sp. nov. (Hymenoptera: Figitidae), a virulent parasitoid of dunni group flies, especially Drosophila antillea. Leptopilina n. sp. is nested within an early-branching clade of Leptopilina , offering insights into the evolution of this important genus of Drosophila parasitoids. We present a high-quality assembly for this wasp's 1Gbp genome, and for its bacterial endosymbiont: Wolbachia strain " w Lmal". Furthermore, we show that w Lmal induces parthenogenesis in the wasp, and that these wasps are reliant upon their Wolbachia infections to produce female offspring. Finally, comparison to historical museum specimens indicate that Leptopilina n. sp. had been collected approximately 40 years prior from the nearby island of Guadeloupe and were also asexually reproducing. This work represents one of only a handful of studies in which field biology, taxonomy, systematics, genomics, and experimental biology are integrated into a species description: showcasing the possibilities for biodiversity research in the genomic era.},
}

@article {pmid40326397,
year = {2025},
author = {Rissanen, J and Freitak, D},
title = {Chronic exposure to nicotine in diet enhances the lethal effect of an entomopathogenic fungus in the ant Cardiocondyla obscurior.},
journal = {Biology open},
volume = {14},
number = {5},
pages = {},
doi = {10.1242/bio.061928},
pmid = {40326397},
issn = {2046-6390},
support = {//Karl-Franzens-Universitat Graz/ ; },
mesh = {*Nicotine/toxicity ; *Ants/microbiology/drug effects/physiology ; Animals ; *Diet ; Symbiosis ; },
abstract = {Nicotine is a naturally occurring alkaloid that has acute toxic effects for insects and affects their behaviour even in sublethal amounts. In addition, nicotine is shown to accumulate and pollute environments through the use of commercially produced pesticides and tobacco products. We investigated how nicotine-polluted diets in two different concentrations impacted colony fitness in the ant Cardiocondyla obscurior, compared to a nicotine-free diet. We measured brood production and development, changes in relative abundances of bacterial endosymbionts, and worker survival in combination with a fungal pathogen. Chronic exposure to nicotine caused a concentration-dependent effect in enhancing the lethality of the fungal infection, with higher concentrations causing higher mortality in infected colonies. In the absence of pathogens, nicotine had no effect on worker survival. Furthermore, nicotine did not affect brood production or development, nor clearly affect the abundances of the bacterial endosymbionts. Our results show that nicotine pollution in the environment can negatively affect ant fitness through synergistic effects in combination with a fungal pathogen. Pathogens play a significant part in the decline of insects, and the influence that nicotine pollution may have in exacerbating them should receive more attention.},
}

*Nicotine/toxicity
*Ants/microbiology/drug effects/physiology
Animals
*Diet
Symbiosis

@article {pmid40320312,
year = {2025},
author = {Thia, JA and Dorai, APS and Hoffmann, AA},
title = {Symbiotic bacteria and pest control: plant toxins, chemical pesticides, and fungal entomopathogens.},
journal = {Trends in microbiology},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.tim.2025.04.007},
pmid = {40320312},
issn = {1878-4380},
abstract = {Bacterial symbionts in pests are being increasingly investigated to assess their potential uses for sustainable control approaches. We undertook a review and analysis of the impacts of endosymbionts and gut symbionts on responses to toxins from plants and pesticides, and to attack by fungal entomopathogens. Despite methodological issues affecting estimates of effect sizes, there is evidence for symbionts increasing resistance to all three agents. However, impacts can be small, and for pesticides, these may not reach levels required for resistance at field rates. Negative or neutral effects may be underreported. Further complications arise because host genotype and the environment impact symbiont effects. We anticipate rapid progress in this area over coming years that should clarify practical implications of these effects.},
}

@article {pmid40288426,
year = {2025},
author = {Soliman, AM and Mahmoud, HYAH and Amer, MM and Mohamed, S and Hifumi, T and Tanaka, T},
title = {Molecular prevalence and phylogenetic characterization of Francisella-like endosymbionts in ticks infesting camels and cattle from Southern Egypt.},
journal = {Microbial pathogenesis},
volume = {},
number = {},
pages = {107639},
doi = {10.1016/j.micpath.2025.107639},
pmid = {40288426},
issn = {1096-1208},
abstract = {Ticks serve as vectors for numerous pathogens affecting human and animal health and harbor various microorganisms, including Francisella-like endosymbionts (FLEs), whose potential pathogenicity remains uncertain. In Egypt, data on FLEs, particularly in Southern Egypt, are limited, despite the importance of tick-borne pathogen surveillance in livestock. This study represents the first report of FLEs in Southern Egypt and the first detection of FLEs in Rhipicephalus annulatus in Egypt. A total of 726 ticks infesting cattle and camels were collected from various locations in Southern Egypt. Ticks were identified using both morphological and molecular techniques based on the 16S rRNA gene, and FLE detection was performed using PCR assays targeting a fragment of the Francisella 16S rRNA gene. Francisella DNA was detected in 60.1% (288/479) of the examined ticks, with the highest prevalence in Hyalomma marginatum (100%, 4/4), followed by Hyalomma dromedarii (74.8%, 243/325), and R. annulatus (27.3%, 41/150). Sequencing of 19 positive samples revealed that H. dromedarii (n = 13), H. marginatum (n = 2), and R. annulatus (n = 4) carried FLE sequences with 99-100% similarity to strains previously identified in ticks worldwide. Given the high prevalence of FLEs in livestock-associated ticks, further research should focus on characterizing these strains, assessing their role in tick-borne pathogen ecology, and evaluating potential implications for human and animal health.},
}

@article {pmid40282203,
year = {2025},
author = {Román-Escrivá, P and Bernabeu, M and Paganin, E and Díaz-Villanueva, W and Verdú, M and Oliver, JL and Arnau, V and Moya, A},
title = {Metrics of Genomic Complexity in the Evolution of Bacterial Endosymbiosis.},
journal = {Biology},
volume = {14},
number = {4},
pages = {},
doi = {10.3390/biology14040338},
pmid = {40282203},
issn = {2079-7737},
support = {PID2019-105969GB-I00//Ministerio de Ciencia, Innovación y Universidades/ ; CIPROM/2021/042//Generalitat Valenciana/ ; FPU21/03813//Ministerio de Universidades, Spain/ ; },
abstract = {Endosymbiosis can be considered a regressive or degenerative evolutionary process characterized at the genomic level by genome erosion and degeneration due to high mutational pressure toward AT (adenine and thymine) bases. The genomic and biological complexity of endosymbionts must be lower than that of the free-living bacteria from which they evolved. In the present work, we contrasted whether two proposed metrics for measuring genomic complexity in both types of bacteria, GS and BB, reflect their complexity, expecting higher values in free-living bacteria than in endosymbionts. On the other hand, we endeavored to delve into the factors that contribute to the reduction in metric values in endosymbionts, as well as their eventual relationship with six genomic parameters associated with functionality. This study aimed to test the robustness of these proposed metrics in a well-known biological scenario, such as the endosymbiosis process.},
}

@article {pmid40275784,
year = {2025},
author = {Yamagishi, D and Onuma, R and Matsunaga, S and Miyagishima, SY and Maruyama, S},
title = {Algal Symbiont Diversity and Host Fitness Variation in Amoebozoan Photosymbiosis.},
journal = {The Journal of eukaryotic microbiology},
volume = {72},
number = {3},
pages = {e70008},
doi = {10.1111/jeu.70008},
pmid = {40275784},
issn = {1550-7408},
support = {JPMJCR20S6//Japan Science and Technology Agency/ ; JPMJSP2108//Japan Science and Technology Agency/ ; 22H02697//Japan Society for the Promotion of Science/ ; 22H05668//Japan Society for the Promotion of Science/ ; 23H04962//Japan Society for the Promotion of Science/ ; 23K23960//Japan Society for the Promotion of Science/ ; 24H01462//Japan Society for the Promotion of Science/ ; 24KJ0740//Japan Society for the Promotion of Science/ ; },
mesh = {*Symbiosis ; *Amoebozoa/physiology/growth & development ; *Microalgae/physiology ; Photosynthesis ; },
abstract = {Photosymbioses, the symbiotic relationships between microalgae and non-photosynthetic eukaryotes, are sporadically found in many eukaryotic lineages. Only a few taxa, such as cnidarians and ciliates hosting algal endosymbionts, have been actively studied, which has hindered understanding the universal mechanisms of photosymbiosis establishment. In Amoebozoa, few species are reported as photosymbiotic, and how the photosymbioses are established is still unclear. To investigate the extent to which one of the photosymbiotic amoebae, Mayorella viridis, depends on their symbionts, the amoebae were treated with reagents known to induce the collapsing of photosymbioses in other species. We succeeded in removing algal symbionts from the hosts with 2-amino-3-chloro-1,4-naphthoquinone. While the apo-symbiotic amoebae grew to the same extent as the symbiotic state when they fed on prey, their survival rates were lower than those of the symbiotic ones during starvation, suggesting that the impact of the photosymbiosis on fitness is condition-dependent. Furthermore, we showed that the photosymbiotic state was reversible by feeding two strains of the green alga Chlorella to the apo-symbiotic amoebae. The efficiencies of ingesting algal cells significantly differed between algal strains. These results suggest that the photosymbiotic relationship in the amoeba is facultative and that different algal strains have discrete symbiotic abilities to the amoeba.},
}

*Symbiosis
*Amoebozoa/physiology/growth & development
*Microalgae/physiology
Photosynthesis

@article {pmid40274861,
year = {2025},
author = {Biswas, S and Rajkonwar, J and Jena, SR and Gogoi, P and Nirmolia, T and Vinayagam, S and Hazarika, G and Sihag, AK and Borah, B and Pebam, R and Kaur, H and Baruah, K and Narain, K and Subbarao, SK and Bhattacharyya, DR and Borkakoty, B and Bhowmick, IP},
title = {Detection of a sympatric cryptic species mimicking Aedes albopictus (Diptera: Culicidae) in dengue and Chikungunya endemic forest villages of Tripura, India, posing a daunting challenge for vector research.},
journal = {Scientific reports},
volume = {15},
number = {1},
pages = {14237},
pmid = {40274861},
issn = {2045-2322},
abstract = {The Aedes (Stegomyia) albopictus (Skuse, 1985) (Diptera: Culicidae) is one of the major vectors for Dengue and Chikungunya. However, our study uncovered another mosquito species morphologically similar to Ae. albopictus but is genetically different. The male genitalia of this species possess minute differences in the IX tergum with Ae. albopictus. Nucleotide diversity and mean genetic distance analysis confirmed the genetic difference from Ae. albopictus and other Aedes species. However, this species has a significant degree of genetic similarity with the cryptic species of Ae. albopictus earlier reported from Vietnam and China. The time tree revealed the median divergence time of this species and Ae. albopictus species to be approximately 36.13 million years ago. This study marks the discovery of an Aedes nr. Albopictus species resembling Ae. albopictus in India and third in the world, also reports the distinct morphological feature of the male genitalia for the first time. Our study indicates the sympatric behavior of this species as it shares the breeding habitat of Ae. albopictus. The absence of endosymbiont Wolbachia in this species raises the possibility of reproductive isolation with Ae. albopictus leading to sympatric speciation and increasing virus-carrying capability for this species, having significant implications for vector-borne disease control.},
}

@article {pmid40269010,
year = {2025},
author = {Heidari Latibari, M and Carolina Arias-Penna, D and Ghafouri Moghaddam, M and Butcher, BA},
title = {Bacterial symbiont as game changers for Aphis craccivora Koch's fitness and survival across distinct climate types.},
journal = {Scientific reports},
volume = {15},
number = {1},
pages = {14208},
pmid = {40269010},
issn = {2045-2322},
support = {BCG_FF_68_178_2300_039//Thailand Science Research and Innovation/ ; },
abstract = {Symbiotic bacteria play a crucial role in the survival, development, and adaptation of aphids to environmental conditions. Buchnera aphidicola (Enterobacterales: Erwiniaceae), the obligate endosymbiont of aphids, is essential for their fitness, while facultative symbionts may provide additional ecological advantages under specific conditions. A comprehensive understanding of how these symbiotic relationships respond to different climatic environments is essential for assessing aphid adaptability and potential implications for biological control. The present study investigates the vital interactions between the obligate bacterial endosymbiont, Buchnera aphidicola, and four facultative bacterial endosymbionts (Arsenophonus sp., Hamiltonella defensa, Serratia symbiotica, and Regiella insecticola), in black cowpea aphid (BCA), in the context of different climate conditions. The BCA specimens were obtained from the leaves of the host plant, alfalfa, cultivated in three distinct climates: cold semi-arid, hot desert, and humid subtropical climates. The findings, as anticipated, indicated a pervasive prevalence of B. aphidicola in BCAs infesting alfalfa crops across all three climate types. In contrast, the BCAs of each climate type exhibited a distinct array of facultative symbionts. The highest number of facultative endosymbionts was exhibited by BCAs from the humid subtropical climate, followed by BCAs from the cold semi-arid climate, whereas none of them were detected in BCAs from the hot desert climate. Rigiella insecticola was not detected molecularly in any of the BCAs from the three climates. Following the eradication of the obligate symbiont Buchnera aphidicola by the antibiotic rifampicin in BCAs, the effects on three categories of parameters were assessed, including life cycle stages, reproductive traits, and external morphological characteristics of adults. The most significant adverse effects were observed in BCAs inhabiting hot desert followed by those inhabiting cold semi-arid climate; detrimental effects in BCAs of the humid subtropical climate were considerably less pronounced. The observed discrepancies in the parameters of BCAs from the humid subtropical climate can be attributed to the presence of a greater number of facultative symbionts, especially the presence of Serratia symbiotica (Enterobacterales: Yersiniaceae). Following the eradication of B. aphidicola, this facultative symbiont continues to complement the functions of B. aphidicola in the host's survival. Conversely, the low presence of facultative symbionts in cold semi-arid climate or even their absence in hot desert climate exacerbates the negative effects of obligate symbiont eradication. These findings highlight the crucial role of symbionts in aphid biology across a spectrum of climatic conditions, and suggest that shifts in symbiotic relationships may modulate aphid fitness, which could have implications for biological control programs.},
}

@article {pmid40266732,
year = {2025},
author = {Duque-Granda, D and Vivero-Gómez, RJ and González Ceballos, LA and Junca, H and Duque, SR and Aroca Aguilera, MC and Castañeda-Espinosa, A and Cadavid-Restrepo, G and Gómez, GF and Moreno-Herrera, CX},
title = {Exploring the Diversity of Microbial Communities Associated with Two Anopheles Species During Dry Season in an Indigenous Community from the Colombian Amazon.},
journal = {Insects},
volume = {16},
number = {3},
pages = {},
doi = {10.3390/insects16030269},
pmid = {40266732},
issn = {2075-4450},
support = {Hermes 57545//Universidad Nacional de Colombia/ ; },
abstract = {Malaria disease affects millions of people annually, making the Amazon Basin a major hotspot in the Americas. While traditional control strategies rely on physical and chemical methods, the Anopheles microbiome offers a promising avenue for biological control, as certain bacteria can inhibit parasite development and alter vector immune and reproductive systems, disrupting the transmission cycle. For this reason, this study aimed to explore the bacterial communities in An. darlingi and An. triannulatus s.l., including breeding sites, immature stages, and adults from San Pedro de los Lagos (Leticia, Amazonas) through next-generation sequencing of the 16S rRNA gene. The results revealed a higher bacterial genus richness in the L1-L2 larvae of An. triannulatus s.l. Aeromonas and Enterobacter were prevalent in most samples, with abundances of 52.51% in L3-L4 larvae and 48.88% in pupae of An. triannulatus s.l., respectively. In breeding site water, Verrucomicrobiota bacteria were the most dominant (52.39%). We also identified Delftia (15.46%) in An. triannulatus s.l. pupae and Asaia (98.22%) in An. triannulatus, linked to Plasmodium inhibition, and Elizabethkingia, in low abundances, along with Klebsiella and Serratia, known for paratransgenesis potential. Considering the high bacterial diversity observed across the different mosquito life stages, identifying bacterial composition is the first step towards developing new strategies for malaria control. However, the specific roles of these bacteria in anophelines and the malaria transmission cycle remain to be elucidated.},
}

@article {pmid40255466,
year = {2025},
author = {Mfangnia, CNT and Tonnang, HEZ and Tsanou, B and Keith Herren, J},
title = {An eco-epidemiological model for malaria with Microsporidia MB as bio-control agent.},
journal = {Modeling earth systems and environment},
volume = {11},
number = {3},
pages = {221},
pmid = {40255466},
issn = {2363-6203},
abstract = {Microsporidia MB is an endosymbiont which naturally infects Anopheles mosquitoes. Due to its ability to block Plasmodium transmission, it shows potential as a bio-based agent for the control of malaria. Its self-sustainability is promising, as it can spread through both vertical and horizontal transmissions. However, its low prevalence in mosquito populations remains a challenge. We develop an eco-epidemiological mathematical model describing the co-dynamics of Microsporidia MB (within mosquito population) and malaria (within human population). The model is used to assess the potential of Microsporidia MB-infected mosquitoes on the control of malaria infection. The results on the basic reproduction numbers, the stability of the equilibria, and the existence of bifurcations are obtained, providing conditions for the extinction and persistence of MB-infected mosquitoes. We highlight relevant threshold parameters for the elimination and persistence of MB-infected mosquitoes and malaria-infected individuals. Using real data from Kenya, we found that, given a horizontal transmission rate between 0 and 0.5, a minimum vertical rate of 0.55 is required to avoid extinction of MB-infected mosquitoes. The predicted prevalence of MB-infected mosquitoes using transmission rates reported from lab experiments align with the observed low prevalence of MB-infected mosquitoes in the field, thereby validating our model and results. Finally, predictions indicate that increasing MB mosquito infection could effectively control malaria, with target prevalence varying by region: 15% in Highland, 40% on the coast, and 70% in the Lake region. This study offers insights into the use of bio-based vector population replacement solutions to reduce malaria incidence in regions where Microsporidia MB is prevalent.},
}

@article {pmid40253413,
year = {2025},
author = {Tian, J and Liu, J and Li, K and Zhong, L and Lu, M and Jiang, H and Jie, R and Wang, X and Zhang, B},
title = {Tick-borne agents in the fowl tick Argas persicus from northwest and northeast China.},
journal = {Parasites & vectors},
volume = {18},
number = {1},
pages = {145},
pmid = {40253413},
issn = {1756-3305},
support = {S202310760014//Xinjiang Medical University College students' innovation and entrepreneurship plan project/ ; 2022jzbjl16//the Key Supporting Scientific Research Projects of Beijing Road Medical Sector, General Hospital of Xinjiang Military Region/ ; YXYJ20230203//the Open Project Program of Institute of Medical Sciences of Xinjiang Medical University/ ; },
mesh = {Animals ; China/epidemiology ; *Argas/microbiology ; *Rickettsia/isolation & purification/genetics/classification ; Phylogeny ; Coxiella/isolation & purification/genetics/classification ; *Tick-Borne Diseases/microbiology/epidemiology ; RNA, Ribosomal, 16S/genetics ; DNA, Bacterial/genetics/chemistry ; },
abstract = {Although tick-borne agents have been extensively studied, etiological investigations on soft ticks are still relatively rare. In this study, we collected 114 Argas persicus ticks from two provinces (Xinjiang and Heilongjiang) located in northwest and northeast China, respectively, and screened them for tick-borne agents. Two Rickettsia species were identified in A. persicus ticks from Heilongjiang Province: Rickettsia hoogstraalii (27.3%, 18/66) and a previously unidentified species (12.2%, 8/66). The 16S rDNA, gltA, groEL, and ompB genes of the latter have 98.8%, 93.1%, 94.3%, and 91.2% nucleotide identities to reported species, suggesting that it represents a novel species. It belongs to the ancient group of Rickettsia and is located in the basal position of the phylogenetic trees. Additionally, Coxiella endosymbiont was detected in A. persicus ticks from both locations with 100% positive rates. Furthermore, the Coxiella endosymbionts from different locations form distinct phylogenetic groups, indicating that one tick species can harbor different Coxiella endosymbionts.},
}

Animals
China/epidemiology
*Argas/microbiology
*Rickettsia/isolation & purification/genetics/classification
Phylogeny
Coxiella/isolation & purification/genetics/classification
*Tick-Borne Diseases/microbiology/epidemiology
RNA, Ribosomal, 16S/genetics
DNA, Bacterial/genetics/chemistry

@article {pmid40252916,
year = {2025},
author = {Dainty, KR and Duyvestyn, JM and Flores, HA},
title = {Targeted knockdown of in vitro candidates does not alter Wolbachia density in vivo.},
journal = {Journal of invertebrate pathology},
volume = {},
number = {},
pages = {108346},
doi = {10.1016/j.jip.2025.108346},
pmid = {40252916},
issn = {1096-0805},
abstract = {The bacterial endosymbiont Wolbachia has emerged as an effective biocontrol method to reduce arbovirus transmission. Transinfection of wMel Wolbachia from Drosophila melanogaster to Aedes aegypti results in the transfer of important Wolbachia-induced phenotypes including the reproductive modification, cytoplasmic incompatibility, and inhibition of viruses including dengue and chikungunya. However, the mechanisms underlying these critical traits as well other Wolbachia-host interactions are still not fully understood. Recently an in vitro genome wide RNAi screen was performed on wMel-infected Drosophila S2 cells and identified large cohorts of host genes that alter wMel density when targeted. If these findings can be replicated in vivo, this would provide a powerful tool for modulating wMel density both systemically and in a tissue-specific manner allowing for interrogation of wMel-host interactions. Here, we used the GAL4/UAS system to express RNAi molecules targeting host gene candidates previously identified to dysregulate wMel density in vitro. We found systemic knockdown of two candidate D. melanogaster genes does not lead to wMel density dysregulation. To explore the lack of consistency between our study and previous work, we also examined native tissue-specific density of wMel in D. melanogaster. We show density is varied between tissues and find that individual tissue densities are not reliable linear predictors of other tissue densities. Our results demonstrate the complexities of implementing in vitro findings in systemic applications.},
}

@article {pmid40252292,
year = {2025},
author = {Cournoyer, JE and De, BC and Mehta, AP},
title = {Molecular and biochemical insights from natural and engineered photosynthetic endosymbiotic systems.},
journal = {Current opinion in chemical biology},
volume = {87},
number = {},
pages = {102598},
doi = {10.1016/j.cbpa.2025.102598},
pmid = {40252292},
issn = {1879-0402},
abstract = {Mitochondria and chloroplasts evolved through the transformation of bacterial endosymbionts established within the host cells. Studies on these organelles have provided several phylogenetic and biochemical insights related to this remarkable evolutionary transformation. Additionally, comparative studies between naturally existing endosymbionts and present-day organelles have allowed us to identify important common features of endosymbiotic evolution. In this review, we discuss hallmarks of photosynthetic endosymbiotic systems, particularly focusing on some of the fascinating molecular changes that occur in the endosymbiont and the host as the endosymbiont/host chimera evolves and transforms endosymbionts into organelles; these include the following: (i) endosymbiont genome minimization and host/endosymbiont gene transfer, (ii) protein import/export systems, (iii) metabolic crosstalk between the endosymbiont, (iv) alterations to the endosymbiont peptidoglycan, and (v) host-controlled replication of endosymbionts/organelles. We discuss these hallmarks in the context of naturally existing photosynthetic endosymbiotic systems and present-day chloroplasts. Further, we also briefly discuss laboratory efforts to engineer endosymbiosis between photosynthetic bacteria and host cells, the lessons learned from these studies, future directions of these studies, and their implications on evolutionary biology and synthetic biology.},
}

@article {pmid40245248,
year = {2025},
author = {Chilton, NB and Thampy, PR and Wolbaum, CR and Sterling, EE and Thoroughgood, JT and Berg, ED and Halpin, AS and Diyes, CP and Yunik, MEM and Díaz-Sánchez, AA and Rochon, K and Lysyk, TJ and Dergousoff, SJ},
title = {Genetic diversity and phylogeographic relationships of Dermacentor variabilis (Acari: Ixodidae) within an established population in southern Manitoba (Canada), and the prevalence of Rickettsia montanensis and Francisella-like endosymbionts.},
journal = {Journal of medical entomology},
volume = {},
number = {},
pages = {},
doi = {10.1093/jme/tjaf010},
pmid = {40245248},
issn = {1938-2928},
abstract = {The primary objective of this study was to determine if DNA sequences of the mitochondrial (mt) cytochrome oxidase c subunit 1 gene (cox1) and/or the mt 16S ribosomal RNA (rRNA) gene can be used to study the population genetics and phylogeography of the American dog tick, Dermacentor variabilis (Say). DNA sequences were determined for 200 adult ticks collected from an established population in a region of Manitoba (Canada) where there have been recent outbreaks of bovine anaplasmosis. Given this, a secondary objective was to test these ticks for the presence of Anaplasma marginale Theiler and 2 other bacterial pathogens, Rickettsia rickettsii Brumpt and Francisella tularensis (McCoy and Chapin 1912) Dorofe'ev 1947. However, no ticks were PCR-positive for these bacteria, whereas 15% of ticks were PCR-positive for R. montanensis Weiss and Moulder and 96% contained Francisella-like endosymbionts. Nucleotide and haplotype diversity among ticks was greater for cox1 than the 16S rRNA gene, thus cox1 is more useful for examining the genetic diversity within and among D. variabilis populations. The 33 cox1 haplotypes could be separated into 3 haplogroups, but when combined with sequence data from GenBank, 6 clades were evident, 2 of which comprised ticks from primarily Saskatchewan, Manitoba, western Ontario, South Dakota, and Wisconsin. These findings indicate that cox1 can be used to understand the phylogeography of D. variabilis, but more sequences are needed from individuals in other populations across geographical range of this tick species, particularly those on the Canadian prairies where D. variabilis is undergoing range expansion.},
}

@article {pmid40240454,
year = {2025},
author = {Leroy, E and Gao, S and Gonzalez, M and Ellies-Oury, MP and Tuda, M},
title = {Wolbachia infection facilitates adaptive increase in male egg size in response to environmental changes.},
journal = {Scientific reports},
volume = {15},
number = {1},
pages = {13213},
pmid = {40240454},
issn = {2045-2322},
support = {19K06840//JSPS/ ; },
mesh = {Animals ; *Wolbachia/physiology ; Male ; Female ; *Ovum/microbiology/physiology ; *Coleoptera/microbiology/physiology ; Climate Change ; Symbiosis ; *Adaptation, Physiological ; Environment ; Temperature ; Longevity ; },
abstract = {Under challenging conditions such as maladapted biotic and abiotic conditions, females can plastically adjust their egg size (gamete or zygote size) to counteract fitness declines early in life. Recent evidence suggests that endosymbionts may enhance this egg-size plasticity. Possible endosymbionts' modification of impact of multiple stressors is not well explored. Therefore, this study aims to test (1) whether Wolbachia infection influences the plasticity of parental investment in egg size under suboptimal environmental conditions and (2) whether the plasticity depends on the sex of eggs. We used three lines of the azuki bean beetle (Callosobruchus chinensis): a line coinfected with the wBruCon and wBruOri Wolbachia strains, a cured line infected solely with the wBruCon, and an uninfected (cured) line. These lines were subjected to either a control environment or a simulated climate change environment (elevated temperature and carbon dioxide levels, eT&CO2) to examine Wolbachia infection effects on parental investment in their offspring (egg size) and its subsequent impact on offspring fitness, including survival, development, and adult lifespan under starvation. After two days of eT&CO2 exposure, coinfected parents increased male egg size only. Larger eggs developed faster in both sexes and exhibited higher survival. However, offspring adult lifespan was not influenced by egg size but by environment, sex, Wolbachia infection, and development time: eT&CO2 reduced male lifespan but not female lifespan, the singly-infected line females lived longer than coinfected and uninfected line females, and shorter development time linked to longer lifespan. The negative correlation between development time and lifespan was higher under eT&CO2 but not sex-specific. This study is the first to demonstrate sex-specific egg size plasticity associated with Wolbachia infection in species with sex determination systems other than haplodiploid.},
}

Animals
*Wolbachia/physiology
Male
Female
*Ovum/microbiology/physiology
*Coleoptera/microbiology/physiology
Climate Change
Symbiosis
*Adaptation, Physiological
Environment
Temperature
Longevity

@article {pmid40237471,
year = {2025},
author = {Njogu, AK and Logozzo, F and Conner, WR and Shropshire, JD},
title = {Counting rare Wolbachia endosymbionts using digital droplet PCR.},
journal = {Microbiology spectrum},
volume = {},
number = {},
pages = {e0326624},
doi = {10.1128/spectrum.03266-24},
pmid = {40237471},
issn = {2165-0497},
abstract = {Wolbachia is the most widespread animal-associated intracellular microbe, living within the cells of over half of insect species. Since they can suppress pathogen replication and spread rapidly through insect populations, Wolbachia is at the vanguard of public health initiatives to control mosquito-borne diseases. Wolbachia's abilities to block pathogens and spread quickly are closely linked to their abundance in host tissues. The most common method for counting Wolbachia is quantitative polymerase chain reaction (qPCR), yet qPCR can be insufficient to count rare Wolbachia, necessitating tissue pooling and consequently compromising individual-level resolution of Wolbachia dynamics. Digital droplet PCR (ddPCR) offers superior sensitivity, enabling the detection of rare targets and eliminating the need for sample pooling. Here, we report three ddPCR assays to measure total Wolbachia abundance, Wolbachia abundance adjusted for DNA extraction efficiency, and Wolbachia density relative to host genome copies. Using Drosophila melanogaster with wMel Wolbachia as a model, we show these ddPCR assays can reliably detect as few as 7 to 12 Wolbachia gene copies in a 20 µL reaction. The designed oligos are homologous to sequences from at least 106 Wolbachia strains across supergroup A and 53 host species from the Drosophila, Scaptomyza, and Zaprionus genera, suggesting broad utility. These highly sensitive ddPCR assays are expected to significantly advance Wolbachia-host interactions research by enabling the collection of molecular data from individual insect tissues. Their ability to detect rare Wolbachia will be especially valuable in applied and natural field settings where pooling samples could obscure important variation.IMPORTANCEWolbachia bacteria live inside the cells of many animals, especially insects. In many insect species, almost every individual carries Wolbachia. How common Wolbachia becomes within a population often depends on how much of it is present in the insect's body. Therefore, accurately measuring Wolbachia levels is crucial for understanding how these bacteria interact with their hosts and spread. However, traditional molecular assays can lack the sensitivity needed for accurate, individual-level quantification of rare Wolbachia. Here, we present three highly sensitive digital droplet PCR assays for Wolbachia detection, offering superior sensitivity compared to existing methods. These assays will be useful for studies that measure Wolbachia abundance and related phenotypes in individual insects, providing enhanced resolution and improving efforts to characterize the mechanisms that govern phenotypic variation.},
}

@article {pmid40236481,
year = {2025},
author = {Alimu, A and Gao, Y and Liu, J and Lu, Y},
title = {Geographic factors influence communities of symbiotic bacterial communities in Aphis gossypii across China's major cotton regions.},
journal = {Frontiers in microbiology},
volume = {16},
number = {},
pages = {1569543},
pmid = {40236481},
issn = {1664-302X},
abstract = {INTRODUCTION: Aphids are often infected with diverse bacterial symbionts that enhance their ecological adaptation. While geographic factors significantly influence aphid bacterial communities, research on environmental effects on the cotton aphid Aphis gossypii Glover feeding on cotton plants across China's major cotton-growing regions is limited.

METHODS: This study examined the influence of geographic factors on the endosymbiotic bacterial community and diversity of A. gossypii by analyzing 58 field samples from 24 locations across China's major cotton-growing regions (2021-2022) using 16S rRNA (V3-V4) high-throughput sequencing.

RESULTS AND DISCUSSION: Our results demonstrate that geography is an important factor in shaping the endosymbiotic bacterial composition and diversity of A. gossypii. Among China's three major cotton-growing regions, the Yangtze River Basin exhibited the highest bacterial diversity, followed by the Northwestern Inland Region, and then the Yellow River Basin. Acinetobacter, Lactobacillus, Serratia, and Aeromonas were more abundant in the Yangtze River Basin, with positive correlations observed for Acinetobacter, Serratia, and Aeromonas in relation to annual precipitation. In contrast, Candidatus Uzinura, dominant in southern Xinjiang, displayed negative correlations with precipitation and longitude but a positive correlation with altitude, and this report is the first detection of it in A. gossypii. Buchnera was ubiquitous and negatively associated with both precipitation and temperature, while Arsenophonus showed no significant environmental correlations. These findings highlight the distinct influences of geographic factors on A. gossypii endosymbiotic communities across China's major cotton-growing regions, broadening our understanding of aphid-endosymbiont-environment interactions and offering potential avenues for biocontrol strategies.},
}

@article {pmid40234496,
year = {2025},
author = {Mahmoud, HYAH and Soliman, AM and Shahat, MS and Hroobi, AA and Alghamdi, AH and Almotayri, AM and Tanaka, T and Emeish, WFA},
title = {Molecular detection of Rickettsia aeschlimannii, Borrelia theileri, and Francisella-like endosymbionts in Camelus dromedarius and dogs in Luxor, Egypt.},
journal = {Scientific reports},
volume = {15},
number = {1},
pages = {12872},
pmid = {40234496},
issn = {2045-2322},
mesh = {Animals ; *Camelus/microbiology ; Egypt/epidemiology ; Dogs/microbiology ; *Rickettsia/genetics/isolation & purification ; *Francisella/genetics/isolation & purification ; *Symbiosis ; *Borrelia/genetics/isolation & purification ; RNA, Ribosomal, 16S/genetics ; Phylogeny ; *Rickettsia Infections/veterinary/microbiology/epidemiology ; },
abstract = {Vector-borne bacterial pathogens can cause disease in a range of animals, including dromedary camels and dogs, but epidemiological and molecular studies on these pathogens are scarce in southern Egypt. In this study, we screened camels and dogs in southern Egypt (Luxor) for vector-borne bacterial pathogens, with molecular analysis of 200 blood samples collected from camels and dogs in the region. The Rickettsia aeschlimannii gltA gene was detected in 5% (5/100) of camel blood samples and 1% (1/100) of dog blood samples. This study is the first report of Rickettsia aeschlimannii in camel blood in southern Egypt. Additionally, the 16S rRNA gene of a Francisella-like endosymbiont was detected in both camel and dog blood for the first time, with infection rates of 2% (2/100) in camels and 2% (2/100) in dogs. In dog blood, the Borrelia theileri flaB gene was detected for the first time in southern Egypt at a positivity rate of 5% (5/100). Neither Coxiella nor Bartonella species were detected in this study. In southern Egypt, Rickettsia aeschlimannii, Borrelia theileri, and Francisella-like endosymbionts were detected in camels and dogs, providing valuable information about their infection rate and these findings contribute to a better understanding of their transmission dynamics.},
}

Animals
*Camelus/microbiology
Egypt/epidemiology
Dogs/microbiology
*Rickettsia/genetics/isolation & purification
*Francisella/genetics/isolation & purification
*Symbiosis
*Borrelia/genetics/isolation & purification
RNA, Ribosomal, 16S/genetics
Phylogeny
*Rickettsia Infections/veterinary/microbiology/epidemiology

@article {pmid40228454,
year = {2025},
author = {Asif, A and Koner, S and Hsu, PC and He, BJ and Paul, S and Hussain, B and Hsu, BM},
title = {Synergistic interactions between AMF and MHB communities in the rhizospheric microenvironment facilitated endemic hyperaccumulator plants growth thrive under heavy metal stress in ultramafic soil.},
journal = {Journal of hazardous materials},
volume = {492},
number = {},
pages = {138233},
doi = {10.1016/j.jhazmat.2025.138233},
pmid = {40228454},
issn = {1873-3336},
abstract = {Ultramafic outcrop settings are characterized by long-term heavy metal (HM) stress and nutrient imbalances, making plant resilience highly challenging. This study investigated that how native plant types in the serpentine environment influence the variation of synergistic interactions between rhizosphere arbuscular mycorrhizal fungi (AMF) and mycorrhizal helper bacteria (MHB) communities under HM stress and nutrient-deficient conditions, which support native plant endemism and their HM accumulation potential. The results displayed significant enrichment of key MHB (Rhizobium_tropici, Bacillus_subtilis, Pseudomonas_parafulva, Pseudomonas_akapagensis) and AMF species (Glomus_constrictum, Glomus_aggregatum, Rhizophagus_intraradices, Rhizophagus_irregularis) in rhizosphere soils (q < 0.05). Pseudomonas_chlororaphis and Burkholderia_cepacia were strongly associated with Rhizophagus_irregularis and Glomus_mosseae in Panicum maximum Jacq (PMJ) and Bidens pilosa (BP) under chromium (Cr), and cadmium (Cd) and arsenic (As) stress. Pseudomonas_fluorescens and Bacillus_pabuli were linked to Geosiphon_pyriformis and Glomus_aggregatum in Pueraria montana (PM) under nickel (Ni), lead (Pb), and cobalt (Co) stress, while Arthrobacter_globiformis and Rhizobium_leguminosarum were associated with Glomus_intraradices under copper (Cu) stress in Leucaena leucocephala (LL). Pathways related to nitrogen, phosphorous and potassium (NPK) cycling, HM detoxification, and resistance were enriched, with AMF predominantly symbiotrophic root-endophytic, except for one as lichenized nostoc endosymbiont. Canonical correspondence analysis (CCA) showed HM stress and nutrients influence MHB-AMF symbiosis, while pH moisture content (MC) and electric conductivity (EC) significantly regulate their distribution. Rhizobium_leguminosarum, Rhizobium_tropici, Nitrospira_japonica, and Rhizobium_cauense with Glomus_mosseae and Rhizophagus_irregularis drive NPK cycling in HM-stressed rhizosphere soils. This finding suggested that association between plants type and their functional rhizosphere microbiome promote an eco-friendly strategy for HM recovery from serpentine soil.},
}

@article {pmid40213639,
year = {2025},
author = {Garrote-Sánchez, E and Moya, A and Gil, R},
title = {Determination of the genome-scale metabolic network of Bartonella quintana str. Toulouse to optimize growth for its use as chassis for synthetic biology.},
journal = {Frontiers in bioengineering and biotechnology},
volume = {13},
number = {},
pages = {1527084},
pmid = {40213639},
issn = {2296-4185},
abstract = {INTRODUCTION: Genetically enhanced microorganisms have wide applications in different fields and the increasing availability of omics data has enabled the development of genome-scale metabolic models (GEMs), which are essential tools in synthetic biology. Bartonella quintana str. Toulouse, a facultative intracellular parasite, presents a small genome and the ability to grow in axenic culture, making it a potential candidate for genome reduction and synthetic biology applications. This study aims to reconstruct and analyze the metabolic network of B. quintana to optimize its growth conditions for laboratory use.

METHODS: A metabolic reconstruction of B. quintana was performed using genome annotation tools (RAST and ModelSEED), followed by refinement using multiple databases (KEGG, BioCyc, BRENDA). Flux Balance Analysis (FBA) was conducted to optimize biomass production, and in-silico knockouts were performed to evaluate growth yield under different media conditions. Additionally, experimental validation was carried out by testing modified culture media and performing proteomic analyses to identify metabolic adaptations.

RESULTS: FBA simulations identified key metabolic requirements, including 2-oxoglutarate as a crucial compound for optimal growth. In-silico knockouts of transport genes revealed their essentiality in nutrient uptake. Experimental validation confirmed the role of 2-oxoglutarate and other nutrients in improving bacterial growth, though unexpected decreases in viability were observed under certain supplemented conditions. Proteomic analysis highlighted differential expression of proteins associated with cell wall integrity and metabolic regulation.

DISCUSSION: This study represents a step toward developing B. quintana as a viable chassis for synthetic biology applications. The reconstructed metabolic model provides a comprehensive understanding of B. quintana's metabolic capabilities, identifying essential pathways and growth limitations. While metabolic predictions align with experimental results in key aspects, further refinements are needed to enhance model accuracy and optimize growth conditions.},
}

@article {pmid40209710,
year = {2025},
author = {Arai, H and Wijonarko, A and Katsuma, S and Naka, H and Kageyama, D and Hornett, EA and Hurst, GDD},
title = {Evolution of Wolbachia male-killing mechanism within a host species.},
journal = {Current biology : CB},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.cub.2025.03.027},
pmid = {40209710},
issn = {1879-0445},
abstract = {Male-killing bacterial symbionts, prevalent in arthropods, skew population sex ratios by selectively killing male progeny, profoundly impacting ecology and the evolution of their hosts. Male killing is a convergently evolved trait, with microbes evolving diverse male-killing mechanisms across host species with widely divergent sex determination pathways. A common evolutionary response to male-killing presence is the spread of suppressor mutations that restore male survival. In this study, we demonstrate the evolution of a novel male-killing mechanism that is insensitive to an existing male-killing suppressor. Hypolimnas bolina butterflies from Yogyakarta, Indonesia, showed extreme female-biased population sex ratio associated with high prevalence of a male-killing Wolbachia. This strain, wBol1Y, shared a very recent common ancestor with the previously characterized "suppressed" male-killing strain in the species, wBol1, but it retained its male-killing ability in the presence of the male-killing suppressor. The genome of wBol1Y differed from the suppressed wBol1 in carrying an additional prophage that included strong candidate genes for male killing. In vitro and in vivo data demonstrated that wBol1Y feminized splicing and expression of lepidopteran sex determination pathway genes and that the gene Hb-oscar-present on wBol1Y's unique prophage insert-was sufficient to disrupt the male sex determination pathway. Our study demonstrates that the diversity of male-killing mechanisms is a product both of interaction with varying insect sex determination systems and the evolution of male killing within a host species. Our data indicate that the male killer and host may be involved in escalating arms races, where spreading male-killing suppression drives the evolution of additional systems that reestablish male killing by the symbiont.},
}

@article {pmid40205751,
year = {2025},
author = {Dho, M and Montagna, M and Liu, C and Magoga, G and Forni, G and Alma, A and Gonella, E},
title = {Multilocus sequence typing of the invasive pest Halyomorpha halys (Hemiptera: Pentatomidae) and associated endosymbiont reveals unexplored diversity.},
journal = {Insect science},
volume = {},
number = {},
pages = {},
doi = {10.1111/1744-7917.70034},
pmid = {40205751},
issn = {1744-7917},
abstract = {Halyomorpha halys is an invasive pest affecting a wide range of crops in many regions of the world. Rapid and cost-effective methods to reconstruct its invasion routes are crucial for implementing strategies to prevent further spread. The mitochondrial markers COI and COII and the pseudogene ΔybgF of the primary symbiont "Candidatus Pantoea carbekii" have been analyzed to track the spread of H. halys. However, these markers do not provide sufficient resolution to fully elucidate invasion routes. Here, H. halys individuals from native and invasive populations were analyzed to identify new DNA markers and evaluate their effectiveness in a multilocus sequence typing (MLST) framework. Three new nuclear markers for H. halys (Hh_KsPi, Hh_UP1, Hh_D3PDh) and three new markers for P. carbekii (Pc_TamA, Pc_SucA, Pc_SurA) were identified. Hh_D3PDh was the most informative marker for H. halys, describing two more haplotypes than COI. By integrating Hh_D3PDh with mitochondrial markers, 30 distinct haplotypes were identified, with each of the populations studied exhibiting multiple haplotypes. Pc_SucA was the most informative symbiont marker, and when all P. carbekii markers were combined, symbiont diversity was greatly increased. The low network specialization between the novel nuclear markers and both mitochondrial and symbiont markers underlined the higher power of nuclear markers. Interestingly, perfect network specialization between H. halys COI and symbiont markers was found in populations from invaded areas, suggesting that some holobiont variants may contribute to enhanced invasive ability. A MLST workflow is proposed as a new tool for population genetics analysis and reconstruction of H. halys invasion.},
}

@article {pmid40202691,
year = {2025},
author = {Pimentel, AC and Cesar, CS and Martins, AHB and Martins, M and Cogni, R},
title = {Wolbachia Offers Protection Against Two Common Natural Viruses of Drosophila.},
journal = {Microbial ecology},
volume = {88},
number = {1},
pages = {24},
pmid = {40202691},
issn = {1432-184X},
mesh = {Animals ; *Wolbachia/physiology ; *Drosophila melanogaster/virology/microbiology ; *Drosophila/virology/microbiology ; Symbiosis ; Female ; },
abstract = {Wolbachia pipientis is a maternally transmitted endosymbiont infecting more than half of terrestrial arthropod species. Wolbachia can express parasitic phenotypes such as manipulation of host reproduction and mutualist phenotypes such as protection against RNA virus infections. Because Wolbachia can invade populations by reproductive manipulation and block virus infection, it is used to modify natural insect populations. However, the ecological importance of virus protection is not yet clear, especially due to scarce information on Wolbachia protection against viruses that are common in nature. We used systemic infection to investigate whether Wolbachia protects its host by suppressing the titer of DMELDAV and DMelNora virus, two viruses that commonly infect Drosophila melanogaster flies in natural populations. Antiviral protection was tested in three systems to assess the impact of Wolbachia strains across species: (1) a panel of Wolbachia strains transfected into Drosophila simulans, (2) two Wolbachia strains introgressed into the natural host D. melanogaster, and (3) two native Wolbachia strains in their natural hosts Drosophila baimaii and Drosophila tropicalis. We showed that certain Wolbachia strains provide protection against DMelNora virus and DMELDAV, and this protection is correlated with Wolbachia density, which is consistent with what has been observed in protection against other RNA viruses. Additionally, we found that Wolbachia does not protect its original host, D. melanogaster, from DMELDAV infection. While native Wolbachia can reduce DMELDAV titers in D. baimaii, this effect was not detected in D. tropicalis. Although the Wolbachia protection-induced phenotype seems to depend on the virus, the specific Wolbachia strain, and the host species, our findings suggest that antiviral protection may be one of the mutualistic effects that helps explain why Wolbachia is so widespread in arthropod populations.},
}

Animals
*Wolbachia/physiology
*Drosophila melanogaster/virology/microbiology
*Drosophila/virology/microbiology
Symbiosis
Female

@article {pmid40202301,
year = {2025},
author = {Mahillon, M and Debonneville, C and Groux, R and Roquis, D and Brodard, J and Faoro, F and Foissac, X and Schumpp, O and Dittmer, J},
title = {From insect endosymbiont to phloem colonizer: comparative genomics unveils the lifestyle transition of phytopathogenic Arsenophonus strains.},
journal = {mSystems},
volume = {},
number = {},
pages = {e0149624},
doi = {10.1128/msystems.01496-24},
pmid = {40202301},
issn = {2379-5077},
abstract = {UNLABELLED: Bacteria infecting the plant phloem represent a growing threat worldwide. While these organisms often resist in vitro culture, they multiply both in plant sieve elements and hemipteran vectors. Such cross-kingdom parasitic lifestyle has emerged in diverse taxa via distinct ecological routes. In the genus Arsenophonus, the phloem pathogens "Candidatus Arsenophonus phytopathogenicus" (Ap) and "Ca. Phlomobacter fragariae" (Pf) have evolved from insect endosymbionts, but the genetic mechanisms underlying this transition have not been explored. To fill this gap, we obtained the genomes of both strains from insect host metagenomes. The resulting assemblies are highly similar in size and functional repertoire, rich in viral sequences, and closely resemble the genomes of several facultative endosymbiotic Arsenophonus strains of sap-sucking hemipterans. However, a phylogenomic analysis demonstrated distinct origins, as Ap belongs to the "Triatominarum" clade, whereas Pf represents a distant species. We identified a set of orthologs encoded only by Ap and Pf in the genus, including hydrolytic enzymes likely targeting plant substrates. In particular, both bacteria encode putative plant cell wall-degrading enzymes and cysteine peptidases related to xylellain, a papain-like peptidase from Xylella fastidiosa, for which close homologs are found in diverse Pseudomonadota infecting the plant vasculature. In silico predictions and gene expression analyses further support a role during phloem colonization for several of the shared orthologs. We conclude that the double emergence of phytopathogenicity in Arsenophonus may have been mediated by a few horizontal gene transfer events, involving genes acquired from other Pseudomonadota, including phytopathogens.

IMPORTANCE: We investigate the genetic mechanisms of a transition in bacterial lifestyle. We focus on two phloem pathogens belonging to the genus Arsenophonus: "Candidatus Arsenophonus phytopathogenicus" and "Ca. Phlomobacter fragariae." Both bacteria cause economically significant pathologies, and they have likely emerged among facultative insect endosymbionts. Our genomic analyses show that both strains are highly similar to other strains of the genus associated with sap-sucking hemipterans, suggesting a recent lifestyle shift. Importantly, although the phytopathogenic Arsenophonus strains belong to distant clades, they share a small set of orthologs unique in the genus pangenome. We provide evidence that several of these genes produce hydrolytic enzymes that are secreted and may target plant substrates. The acquisition and exchange of these genes may thus have played a pivotal role in the lifestyle transition of the phytopathogenic Arsenophonus strains.},
}

@article {pmid40185027,
year = {2025},
author = {Jiménez-Leiva, A and Cabrera, JJ and Torres, MJ and Richardson, DJ and Bedmar, EJ and Gates, AJ and Delgado, MJ and Mesa, S},
title = {Haem is involved in the NO-mediated regulation by Bradyrhizobium diazoefficiens NnrR transcription factor.},
journal = {Microbiological research},
volume = {297},
number = {},
pages = {128151},
doi = {10.1016/j.micres.2025.128151},
pmid = {40185027},
issn = {1618-0623},
abstract = {Nitric oxide (NO) and the greenhouse gas (GHG) nitrous oxide (N2O) contribute significantly to climate change. In rhizobia, the denitrifying enzyme c-type nitric oxide reductase (cNor), encoded by norCBQD genes, is crucial for maintaining a delicate balance of NO and N2O levels. In the soybean endosymbiont Bradyrhizobium diazoefficiens, maximal expression of norCBQD genes in response to NO is controlled by NnrR, which belongs to a distinct clade of the CRP/FNR family of bacterial transcription factors. This protein participates in the FixLJ-FixK2-NnrR regulatory cascade that induces denitrification genes expression in response to oxygen limitation and nitrogen oxides. However, the molecular mechanism underpinning NO sensing by B. diazoefficiens NnrR has remained elusive. Here, we revealed that NnrR induces norCBQD gene expression in response to NO uncoupled from the superimposed FixK2 control. Moreover, NO-mediated induction by NnrR is dependent on haem, as the expression of a norC-lacZ fusion was impaired in a hemN2 mutant defective in haem biosynthesis. In vitro studies showed that NnrR bound haem with a 1:1 stoichiometry (monomer:haem), according to titration experiments of recombinant NnrR protein with hemin performed under anaerobic conditions. Furthermore, the full UV-Visible spectra of haem-reconstituted NnrR showed a peak at 411 nm (ferric form), and at 425 nm (ferrous derivative). This latter complex was able to bind NO under anaerobic conditions. Finally, we performed a functional mutagenesis of specific residues in NnrR predicted as putative ligands for haem binding. While H11 was important for norC expression and Nor activity, a H11A-H56A protein variant showed a reduced affinity for haem binding. Taken together, our results identify haem as the cofactor for NnrR-mediated NO sensing in B. diazoefficiens denitrification, with H11 as a key residue for NnrR function, providing the first insight into the mechanism of an NnrR-type protein. These findings advance our understanding of how bacterial systems orchestrate the denitrification process and respond to environmental cues such as NO.},
}

@article {pmid40181281,
year = {2025},
author = {Degnan, PH and Percy, DM and Hansen, AK},
title = {Coupled evolutionary rates shape a Hawaiian insect-symbiont system.},
journal = {BMC genomics},
volume = {26},
number = {1},
pages = {336},
pmid = {40181281},
issn = {1471-2164},
support = {DEB 1241253//NSF/ ; 2019-70016-29066//National Institute of Food and Agriculture/ ; },
mesh = {Animals ; *Symbiosis/genetics ; *Evolution, Molecular ; Phylogeny ; Hawaii ; *Hemiptera/genetics/microbiology/classification ; Genome, Mitochondrial ; Genome, Insect ; },
abstract = {BACKGROUND: The Hawaiian Pariaconus psyllid radiation represents a unique system to study the co-evolution of nuclear, mitochondrial, and endosymbiont genomes. These psyllids, which diversified across the Hawaiian Islands during the last 3-3.5 million years vary with their ecological niches on their plant host 'Ōhi'a lehua (Metrosideros polymorpha) (free-living, open-gall, and closed-gall lifestyles) and harbor one to three beneficial bacterial endosymbionts. Co-evolutionary studies of other multi-endosymbiont insect systems have shown decoupled rates of sequence evolution between mitochondria and endosymbionts. Here we examine the evolutionary trends in Pariaconus psyllids, their mitochondria and their endosymbionts to determine if they fit this paradigm.

RESULTS: We sequenced a new Carsonella genome from the ohialoha species group (closed-gall, one symbiont), revealing a remarkable degree of gene conservation between two of the most divergent species from this diverse species group that has dispersed across multiple islands. Further, despite the rapid radiation of psyllid species, we observed complete synteny among mitochondrial genomes from all six Pariaconus species in this study, suggesting the preservation of genome structure due to strong purifying selection. Phylogenetic analyses of the nuclear, mitochondrial, and endosymbiont genomes across these six Pariaconus species revealed correlated rates of substitutions, contrary to prior reports of decoupling between mitochondrial and endosymbiont genomes in other insect systems with multiple symbiont partners. Finally, we found that free-living psyllids with three symbionts exhibited elevated mutation rates (~ 1.2-1.6x) across all genomes and elevated rates of fixation of nonsynonymous substitutions in the insect nuclear genome and one of the endosymbionts.

CONCLUSIONS: This study highlights the interplay between ecological diversification and genomic evolution in Pariaconus. Further, these data indicate that multiple endosymbiont partners alone are not sufficient to result in decoupling rates of sequence evolution. Future work on basal members of this species radiation will refine our understanding of the mechanisms shaping this dynamic insect-symbiont system and its implications for genome evolution.},
}

Animals
*Symbiosis/genetics
*Evolution, Molecular
Phylogeny
Hawaii
*Hemiptera/genetics/microbiology/classification
Genome, Mitochondrial
Genome, Insect

@article {pmid40177692,
year = {2025},
author = {Speer, KA and Víquez-R, L and Frick, WF and Ibarra, A and Simmons, NB and Dittmar, K and Calderón, RS and Preciado, R and Medellín, R and Tschapka, M and Sommer, S and Perkins, SL},
title = {Comparative Community Ecology Reveals Conserved Ectoparasite Microbiomes Amidst Variable Host and Environment Microbiomes.},
journal = {Ecology and evolution},
volume = {15},
number = {4},
pages = {e71120},
pmid = {40177692},
issn = {2045-7758},
abstract = {The microbiome-the community of microorganisms that is associated with an individual animal-has been an important driver of insect biodiversity globally, enabling insects to specialize in narrow, nutrient-deficient diets. The importance of maternally inherited, obligate bacterial endosymbionts in provisioning nutrients missing from these narrow dietary niches has been well studied in insects. However, we know comparatively little about the processes that dictate the composition of non-maternally inherited bacteria in insect microbiomes, despite the importance of these bacteria in insect health, fitness, and vector competence. Here, we used two species of obligate insect ectoparasites of bats, the bat flies (Streblidae) Trichobius sphaeronotus and Nycterophilia coxata, to examine whether the microbiome, beyond obligate bacterial endosymbionts, is conserved or variable across geographic space, between ectoparasite species, or covaries with the external microbiome of their bat hosts or the cave environment. Our results indicate that ectoparasite microbiomes are highly conserved and specific to ectoparasite species, despite these species feeding on the blood of the same bat individuals in some cases. In contrast, we found high geographic variation in the fur microbiome of host bats and that the bat fur microbiome mimics the cave microbiomes. This research suggests that there is a constraint on blood-feeding insect ectoparasites to maintain a specific microbiome distinct from their host and the environment, potentially to meet their nutritional needs. Given that many of these bacteria are not known to be maternally inherited, this research lays the foundation for future examinations of how blood-feeding arthropods acquire and maintain bacteria in their microbiomes.},
}

@article {pmid40172541,
year = {2025},
author = {Yu, Y and Iatsenko, I},
title = {Drosophila symbionts in infection: when a friend becomes an enemy.},
journal = {Infection and immunity},
volume = {},
number = {},
pages = {e0051124},
doi = {10.1128/iai.00511-24},
pmid = {40172541},
issn = {1098-5522},
abstract = {The insect microbiome is comprised of extracellular microbial communities that colonize the host surfaces and endosymbionts that reside inside host cells and tissues. Both of these communities participate in essential aspects of host biology, including the immune response and interactions with pathogens. In recent years, our knowledge about the role of the insect microbiome in infection has increased tremendously. While many studies have highlighted the microbiome's protective effect against various natural enemies of insects, unexpected discoveries have shown that some members of the microbiota can facilitate pathogenic infections. Here, we summarize studies in the fruit fly, Drosophila melanogaster, that have substantially progressed our understanding of host-pathogen-microbiome interactions during infection. We summarize studies on the protective mechanisms of Drosophila gut microbiota, highlight examples of microbiome exploitation by pathogens, and detail the mechanisms of endosymbiont-mediated host protection. In addition, we delve into a previously neglected topic in Drosophila microbiome research-the crosstalk between endosymbionts and gut microbiota. Finally, we address how endosymbionts and gut microbiota remain resilient to host immune responses and stably colonize the host during infection. By examining how the microbiome is influenced by and reciprocally affects infection outcomes, this review provides timely and cohesive coverage of the roles of Drosophila endosymbionts and gut microbiota during infections.},
}

@article {pmid40163815,
year = {2025},
author = {Marinov, GK and Ramalingam, V and Greenleaf, WJ and Kundaje, A},
title = {An updated compendium and reevaluation of the evidence for nuclear transcription factor occupancy over the mitochondrial genome.},
journal = {PloS one},
volume = {20},
number = {3},
pages = {e0318796},
pmid = {40163815},
issn = {1932-6203},
support = {U01 HG009431/HG/NHGRI NIH HHS/United States ; R01 HG008140/HG/NHGRI NIH HHS/United States ; U19 AI057266/AI/NIAID NIH HHS/United States ; P50 HG007735/HG/NHGRI NIH HHS/United States ; UM1 HG009436/HG/NHGRI NIH HHS/United States ; UM1 HG009442/HG/NHGRI NIH HHS/United States ; },
mesh = {*Genome, Mitochondrial ; *Transcription Factors/metabolism/genetics ; Humans ; Animals ; *Cell Nucleus/metabolism/genetics ; Mice ; Chromatin Immunoprecipitation Sequencing ; Chromatin Immunoprecipitation ; Mitochondria/metabolism/genetics ; },
abstract = {In most eukaryotes, mitochondrial organelles contain their own genome, usually circular, which is the remnant of the genome of the ancestral bacterial endosymbiont that gave rise to modern mitochondria. Mitochondrial genomes are dramatically reduced in their gene content due to the process of endosymbiotic gene transfer to the nucleus; as a result most mitochondrial proteins are encoded in the nucleus and imported into mitochondria. This includes the components of the dedicated mitochondrial transcription and replication systems and regulatory factors, which are entirely distinct from the information processing systems in the nucleus. However, since the 1990s several nuclear transcription factors have been reported to act in mitochondria, and previously we identified 8 human and 3 mouse transcription factors (TFs) with strong localized enrichment over the mitochondrial genome using ChIP-seq (Chromatin Immunoprecipitation) datasets from the second phase of the ENCODE (Encyclopedia of DNA Elements) Project Consortium. Here, we analyze the greatly expanded in the intervening decade ENCODE compendium of TF ChIP-seq datasets (a total of 6,153 ChIP experiments for 942 proteins, of which 763 are sequence-specific TFs) combined with interpretative deep learning models of TF occupancy to create a comprehensive compendium of nuclear TFs that show evidence of association with the mitochondrial genome. We find some evidence for chrM occupancy for 50 nuclear TFs and two other proteins, with bZIP TFs emerging as most likely to be playing a role in mitochondria. However, we also observe that in cases where the same TF has been assayed with multiple antibodies and ChIP protocols, evidence for its chrM occupancy is not always reproducible. In the light of these findings, we discuss the evidential criteria for establishing chrM occupancy and reevaluate the overall compendium of putative mitochondrial-acting nuclear TFs.},
}

*Genome, Mitochondrial
*Transcription Factors/metabolism/genetics
Humans
Animals
*Cell Nucleus/metabolism/genetics
Mice
Chromatin Immunoprecipitation Sequencing
Chromatin Immunoprecipitation
Mitochondria/metabolism/genetics

@article {pmid40161691,
year = {2025},
author = {Tekle, YI and Smith, AR and McGinnis, M and Ghebezadik, S and Patel, P},
title = {A new Paramoeba Isolate from Florida Exhibits a Microtubule-Bound Endosymbiont Closely Associated with the Host Nucleus.},
journal = {bioRxiv : the preprint server for biology},
volume = {},
number = {},
pages = {},
doi = {10.1101/2025.03.10.642444},
pmid = {40161691},
issn = {2692-8205},
abstract = {The genera Paramoeba and Neoparamoeba , within the family Paramoebidae (order Dactylopodida), are distinguished by their dactylopodial pseudopodia and the presence of an intracellular eukaryotic symbiont, the Perkinsela -like organism (PLO). Taxonomic classification within these genera has been challenging due to overlapping morphological traits and close phylogenetic relationships. Most species are marine, with some acting as significant parasites, contributing to sea urchin mass mortality and serving as causative agents of Amoebic Gill Disease (AGD). Despite their ecological and economic importance, many aspects of their diversity, biology, evolution, and host interactions remain poorly understood. In this study, we describe a novel amoeba species, Paramoeba daytoni n. sp., isolated from Daytona Beach, Florida. Morphological and molecular analyses confirm its placement within the Paramoeba clade, closely related to P. eilhardi, P. karteshi, and P. aparasomata . Phylogenetic assessments using 18S and COI markers demonstrate the limitations of 18S gene for species delineation, highlighting COI as a more reliable genetic marker for this group. Additionally, observations on PLO morphology, movement, and microtubule association provide insights into the endosymbiotic relationship, reinforcing the need for further research into this unique eukaryote-eukaryote symbiosis.},
}

@article {pmid40161633,
year = {2025},
author = {Cassens, J and Villalta, M and Aguirre, S and Ecklund, L and Stenger, T and Abdi, I and Venigalla, S and Shiffman, E and Bastug, K and Thielen, BK and Faulk, C},
title = {The Genome of the American Dog Tick (Dermacentor variabilis).},
journal = {bioRxiv : the preprint server for biology},
volume = {},
number = {},
pages = {},
pmid = {40161633},
issn = {2692-8205},
support = {T32 AI055433/AI/NIAID NIH HHS/United States ; T32 AR007612/AR/NIAMS NIH HHS/United States ; },
abstract = {The American dog tick (Dermacentor variabilis) is a vector of zoonotic pathogens in North America that poses emerging threats to public health. Despite its medical importance, genomic resources for D. variabilis remain scarce. Leveraging long-read nanopore sequencing, we generated a high-quality genome assembly for D. variabilis with a final size of 2.15 Gb, an N50 of 445 kb, and a BUSCO completeness score of 95.2%. Comparative BUSCO analyses revealed fewer duplicate genes in our assembly than in other Dermacentor genomes, indicating improved haplotype resolution. The mitochondrial genome, assembled as a single circular contig, clustered monophyletically with D. variabilis isolates from the Upper Midwest, corroborating regional phylogenetic relationships. Repetitive element analysis identified 61% of the genome as repetitive, dominated by LINEs and LTR elements, with 24% remaining unclassified, underscoring the need for further exploration of transposable elements in tick genomes. Gene annotation predicted 21,722 putative genes, achieving a protein BUSCO completeness of 80.88%. Additionally, genome-wide methylation analysis revealed 9.9% global 5mC methylation, providing the first insights into epigenetic modifications in D. variabilis. Further, nanopore sequencing detected Rickettsia montanensis and a non-pathogenic Francisella-like endosymbiont. These findings expand our understanding of tick genomics and epigenetics, offering valuable resources for comparative studies and evolutionary analyses.},
}

@article {pmid40144380,
year = {2025},
author = {Gokhman, VE and Ryabinin, AS and Bykov, RA and Ilinsky, YY},
title = {The lowest chromosome number in the family Pteromalidae (Hymenoptera: Chalcidoidea): the karyotype and other genetic features of Pachycrepoideus vindemmiae (Rondani, 1875).},
journal = {Vavilovskii zhurnal genetiki i selektsii},
volume = {29},
number = {1},
pages = {108-112},
doi = {10.18699/vjgb-25-12},
pmid = {40144380},
issn = {2500-0462},
abstract = {Various genetic features of the hitman strain of the widespread parasitoid of Drosophilidae (Diptera), Pachycrepoideus vindemmiae (Rondani, 1875) (Pteromalidae, Pachyneurinae) were studied. This strain was established and is maintained at the Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences (Novosibirsk, Russia). An analysis of air-dried chromosome preparations from prepupae of this parasitoid showed that it has n = 4 and 2n = 8 in males and females, respectively, which is the lowest known chromosome number in the family Pteromalidae. All chromosomes in the karyotype of this species are metacentric. The first and second chromosomes are of similar size, the remaining ones are substantially shorter. The same results were obtained for an additional strain of this species kept at the Moscow State University (Moscow, Russia). A comparison of the DNA sequence of the barcoding region of the mitochondrial cytochrome c oxidase (COI) gene of the hitman strain of P. vindemmiae with those available from the GenBank and BoLD databases demonstrated that this strain clustered together with conspecifics originating from China, Turkey and Italy. Despite certain endosymbionts being previously reported for the genus Pachycrepoideus Ashmead, 1904 as well as for P. vindemmiae itself, the hitman strain turned out to be free of endosymbiotic bacteria in the genera Arsenophonus Gherna et al., 1991, Cardinium Zchori-Fein et al., 2004, Rickettsia da Rocha-Lima, 1916, Spiroplasma Saglio et al., 1973 and Wolbachia Hertig, 1936. The above-mentioned results improve our knowledge of various genetic features of parasitoids of the family Pteromalidae and those of P. vindemmiae in particular.},
}

@article {pmid40143862,
year = {2025},
author = {Sujatha, S and Sindhura, KAV and Koti, PS and Hiremath, S and Muttappagol, M and Vinay Kumar, HD and Shankarappa, KS and Venkataravanappa, V and Reddy, KMS and Reddy, CNL},
title = {Influence of weather and seasonal factors on whitefly dynamics, associated endosymbiotic microbiomes, and Begomovirus transmission causing tomato leaf curl disease: insights from a metagenomic perspective.},
journal = {Frontiers in microbiology},
volume = {16},
number = {},
pages = {1555058},
pmid = {40143862},
issn = {1664-302X},
abstract = {INTRODUCTION: Bemisia tabaci (Gennadius) is a globally significant agricultural pest, responsible for transmitting over 120 plant viruses, including those from the Begomovirus genus, which contribute to considerable crop losses. The species complex comprises cryptic species, associated with a diverse array of bacterial endosymbionts that play essential roles in host nutrition, virus transmission, and overall host adaptability. These endosymbionts are classified into primary and secondary categories, with primary endosymbionts forming obligatory, long-term associations, and secondary endosymbionts influencing factors such as biotype differentiation and vector competency. Notably, these microbial communities enhance B. tabaci's capacity to transmit viruses, including the tomato leaf curl virus (ToLCuV), which poses a significant threat to tomato production.

METHODS: In this study, we examined the population dynamics of B. tabaci across three major tomato-growing regions in Karnataka, South India, focusing on their seasonal associations with endosymbionts and the incidence of tomato leaf curl disease (ToLCuD). Multiple regression analysis was employed to assess the influence of weather parameters on whitefly populations and disease prevalence. Additionally, we constructed a metagenomic profile to evaluate the effects of geographical location, seasonality, environmental factors, and agricultural practices on the bacterial communities associated with B. tabaci. Species-specific primers were used to validate the presence and diversity of these bacterial communities.

RESULTS: Meteorological data revealed a positive correlation between temperature and B. tabaci populations, which corresponded with an increased incidence of ToLCuD. Genetic characterization of the whitefly identified Asia II-5 and Asia II-7 cryptic species as the dominant forms in the surveyed regions, with Portiera emerging as the most prevalent endosymbiont. A more in-depth analysis of the microbial communities associated with B. tabaci, utilizing 16S rRNA metagenomic sequencing, revealed a dominance of the Proteobacteria phylum. The endosymbiotic bacterial consortium was primarily composed of Candidatus Portiera, Candidatus Hamiltonella, Candidatus Rickettsia, and Candidatus Arsenophonus.

DISCUSSION: The metagenomic analysis revealed a highly diverse array of bacterial communities, with 92% of sequences classified under Proteobacteria, representing a spectrum of microbial types associated with B. tabaci ranging from parasitic and pathogenic to mutualistic. Within this phylum, Alphaproteobacteria were predominant, known for their role as facultative symbionts, while Gammaproteobacteria provided essential nutrients to arthropods, enhancing their survival and fitness. The interplay of continuous and intensive tomato cultivation, elevated temperatures, favorable host plants, and abundant viral inoculum creates an ideal environment for the proliferation of B. tabaci and the widespread transmission of ToLCuD. The presence of diverse cryptic species of B. tabaci, which are efficient viral vectors, further complicates the situation. These findings underscore the urgent need for integrated management strategies globally to control both whitefly populations and ToLCuD, ensuring the protection of tomato crops and the sustainability of farmer livelihoods.},
}

@article {pmid40142534,
year = {2025},
author = {Wang, S and Wang, X and Basit, A and Wei, Q and Zhao, K and Zhao, Y},
title = {Interactions Between Endosymbionts Wolbachia and Rickettsia in the Spider Mite Tetranychus turkestani: Cooperation or Antagonism?.},
journal = {Microorganisms},
volume = {13},
number = {3},
pages = {},
pmid = {40142534},
issn = {2076-2607},
support = {No. 32260676,No. 31860508//National Natural Science Foundation of China/ ; No. 2022CB002 - 06//the Program for Young Leading Scientists in Science and Technology of XPCC/ ; No. 2024DA018//the Natural Science Foundation of XPCC/ ; },
abstract = {Maternally inherited endosymbionts are widespread in arthropods, with multiple symbionts commonly co-existing within a single host, potentially competing for or sharing limited host resources and space. Wolbachia and Rickettsia, two maternally-inherited symbionts in arthropods, can co-infect hosts, yet research on their combined impacts on host reproduction and interaction remains scarce. Tetranychus turkestani (Acari: Tetranychidae) is an important agricultural pest mite, characterized by rapid reproduction, a short life cycle, and being difficult to control. Wolbachia and Rickettsia are two major endosymbiotic bacteria present in T. turkestani. This study used diverse parthenogenetic backcross and antibiotic screening to explore the reproductive effects of these two symbionts on T. turkestani. The results show that single Rickettsia infection induced male killing in the amphigenesis of T. turkestani, leading to arrhenotokous embryo death and fewer offspring. Single Wolbachia infection induced strong cytoplasmic incompatibility (CI). During dual infection, CI intensity decreased because Rickettsia's male-killing effect antagonized the Wolbachia-induced CI. Dual-infected mites had increased oviposition, lower mortality, a higher female-to-male ratio, and more offspring, thus enhancing T. turkestani's fitness. These findings will be helpful for understanding the nature of host-endosymbiont interactions and the potential for evolutionary conflicts, offering insights into their co-evolutionary relationship.},
}

@article {pmid40128584,
year = {2025},
author = {Nooma, W and Kaenkan, W and Trinachartvanit, W and Baimai, V and Ahantarig, A},
title = {Molecular prevalence of Coxiella like endosymbionts and the first record of Coxiella burnetii in hard ticks from Southern Thailand.},
journal = {Scientific reports},
volume = {15},
number = {1},
pages = {10129},
pmid = {40128584},
issn = {2045-2322},
support = {PHD 0096/2558//Royal Golden Jubilee Ph.D. (RGJ-PHD) Scholarship/ ; BDC-PG3-163005//Center of Excellence on Biodiversity, Office of Higher Education Commission, Mahidol University/ ; BDC-PG3-163005//Center of Excellence on Biodiversity, Office of Higher Education Commission, Mahidol University/ ; },
mesh = {Animals ; Thailand ; *Coxiella burnetii/genetics/isolation & purification ; *Symbiosis ; *Phylogeny ; Ixodidae/microbiology ; RNA, Ribosomal, 16S/genetics ; Coxiella/genetics/isolation & purification ; },
abstract = {Eight hard tick species were identified among a total of 466 samples collected from vegetation in southern Thailand: Dermacentor compactus (n = 150), D. steini (n = 100), D. auratus (n = 85), D. tricuspis (n = 41), Haemaphysalis hystricis (n = 69), H. semermis (n = 3), H. shimoga (n = 2) and Amblyomma testudinarium (n = 16). In 93 ticks from these 8 species, Coxiella bacteria were detected via 16 S rRNA, groEL (60-kDa chaperone heat shock protein B) and rpoB (β subunit of bacterial RNA polymerase) genes. Interestingly, Coxiella burnetii was detected for the first time in H. hystricis and D. steini in Songkhla Province. Coxiella-like endosymbionts (CLEs) were also found in 84 ticks from 7 species, namely, D. compactus, D. auratus, D. tricuspis, H. hystricis, H. semermis, H. shimoga and A. testudinarium. Among these, CLEs associated with D. compactus and H. semermis were reported for the first time in Thailand. Phylogenetic analysis and generation of a haplotype network clearly revealed 2 distinct groups of Coxiella bacteria, namely, C. burnetii and CLEs. The nucleotide alignment of Coxiella 16 S rRNA revealed differences in bases at 3 positions between C. burnetii and CLEs. Thus, these differences could be used as liable molecular markers for discriminating these 2 groups in hard ticks.},
}

Animals
Thailand
*Coxiella burnetii/genetics/isolation & purification
*Symbiosis
*Phylogeny
Ixodidae/microbiology
RNA, Ribosomal, 16S/genetics
Coxiella/genetics/isolation & purification

@article {pmid40125914,
year = {2025},
author = {Besteiro, S},
title = {Keeping your endosymbiont under control: the enigmatic plastid membrane ATG8ylation in Apicomplexa parasites.},
journal = {Autophagy},
volume = {},
number = {},
pages = {1-5},
doi = {10.1080/15548627.2025.2483445},
pmid = {40125914},
issn = {1554-8635},
abstract = {ATG8ylation of membranes has been increasingly reported over the last few years, in various configurations and across different eukaryotic models. While the unconventional conjugation of ATG8 to the outermost membrane of the plastid in apicomplexan parasites was first observed over a decade ago, it is often overlooked in literature reviews focusing on the ATG8ylation of non-autophagosomal membranes. Here, I provide a brief overview of the current knowledge on plastid ATG8ylation in these parasites and discuss a possible parallel between the evolutionary origin of this plastid and other ATG8ylation processes, such as LC3-associated phagocytosis.},
}

@article {pmid40123057,
year = {2025},
author = {Bastías, DA and Carvalho, L and Jáuregui, R and Johnson, RD and Zhang, W and Gundel, PE},
title = {Is the endophyte-based plant protection against aphids mediated by changes in the insect microbiome?.},
journal = {Insect science},
volume = {},
number = {},
pages = {},
doi = {10.1111/1744-7917.70023},
pmid = {40123057},
issn = {1744-7917},
support = {FONDECYT-2021-1210908//Fondo Nacional de Desarrollo Científico y Tecnológico/ ; A20067//Ministry of Business, Innovation and Employment/ ; },
abstract = {Aphids are important herbivores in natural and managed environments. We studied the response of aphids and their associated microbiota to the presence of the fungal endophyte Epichloë sp. LpTG-3 strain AR37, and the AR37-derived alkaloids in plants. We hypothesized that AR37 and/or AR37-derived alkaloids would reduce the aphid performance, and that this reduction would be associated with endophyte-mediated changes in the abundance, composition, and diversity of beneficial bacterial endosymbionts of aphids (e.g., Buchnera). Plants of Lolium perenne associated with AR37 variants able (wild type and ∆idtA) and unable (∆idtM) to produce indole diterpene alkaloids were challenged with Rhopalosiphum padi aphids. We measured aphid population size, plant biomass, and the abundance, composition and diversity of the aphid's bacterial microbiota. The presence of AR37 increased the resistance of plants against R. padi aphids via the production of indole diterpene alkaloids, and this effect was independent of the plant biomass. The endophyte-mediated reduction in aphid performance was not associated with changes in the abundance, composition and diversity of the insect's bacterial microbiota. However, we cannot rule out that the reduction in aphid performance could be associated with a putative endophyte effect on the bacterial provision of benefits to aphids. Our study highlighted the protective role of endophyte-derived indole diterpene alkaloids against aphids. Further investigations will be needed to determine if there is a link between the endophyte-mediated aphid resistance and the integrity of the insect's bacterial microbiota.},
}

@article {pmid40121938,
year = {2025},
author = {Zheng, W and Fu, J and Huang, J and Wen, Y and Fang, S and Yang, X and Xia, Q},
title = {Coxiella R1 symbiont regulates the Asian long-horned tick on its reproduction and development.},
journal = {Veterinary parasitology},
volume = {336},
number = {},
pages = {110456},
doi = {10.1016/j.vetpar.2025.110456},
pmid = {40121938},
issn = {1873-2550},
abstract = {The Asian long-horned tick Haemaphysalis longicornis, is a hematophagous ectoparasite that causes important public and veterinary health concerns. Different species of ticks harbor a symbiont bacterium of the genus Coxiella. A Coxiella sp. bacterial endosymbiont was highly prevalent in laboratory-reared H. longicornis. The endosymbiont sequence was 100 % identical to those of H. longicornis Coxiella-like endosymbionts and thus named Coxiella R1 in the present study. Coxiella R1 was detected in all stages of tick and in greatest numbers in nymphs and unfed adult females. We manipulated the numbers of Coxiella R1 in ticks by injecting engorged females or capillary tube feeding of flat females with tetracycline. Both of the administration routes were efficient in reducing the symbiont densities. Microinjection of tetracycline solution reduced 25.53 % of Coxiella R1 in eggs harvested just before hatching, whereas, the reduction rate for capillary tube feeding climbed to 81.70 %. Ticks with Coxiella R1 suppression laid abnormal eggs which were wrinkled, flat, and black, and linked each other to form a line. Ticks that had been treated with tetracycline had lower hatching rates in comparison to controls. In addition, larvae with tetracycline treatment less infested hosts and thus had lower engorgement rates than ticks that received PBS alone. The findings indicate that Coxiella R1 is a primary and obligate endosymbiont, and capable of modulating the obligately hematophagous parasites in egg laying and hatching, and larva blood feeding. The results also suggest that tetracycline treatment could be added to an integrated pest management tool menu for control of the Asian long-horned ticks.},
}

@article {pmid40120785,
year = {2025},
author = {Almazán, MC and González-Prieto, G and Pereira, LOR and Díaz-Fernández, M and Portal, G and Cantanhêde, LM and García-Bustos, F and Parodi, C and Cajal, P and Quipildor, M and Nasser, J and Krolewiecki, A and Barrio, A},
title = {Exploring the presence of Leishmania RNA Virus 1 in Leishmania (Viannia) braziliensis isolates from the most endemic area of American tegumentary Leishmaniasis in Argentina.},
journal = {Acta tropica},
volume = {264},
number = {},
pages = {107591},
doi = {10.1016/j.actatropica.2025.107591},
pmid = {40120785},
issn = {1873-6254},
mesh = {Argentina/epidemiology ; Humans ; *Leishmania braziliensis/virology/isolation & purification ; *Leishmaniavirus/isolation & purification/genetics ; Male ; Female ; *Leishmaniasis, Cutaneous/parasitology/epidemiology ; Adult ; Middle Aged ; Polymorphism, Restriction Fragment Length ; Young Adult ; Endemic Diseases ; Adolescent ; Prevalence ; Polymerase Chain Reaction ; },
abstract = {American Tegumentary Leishmaniasis (ATL) comprises a group of diseases caused by protozoan parasites of the Leishmania genus. The endosymbiont Leishmania RNA Virus 1 (LRV1) has been associated with severe disease forms and treatment failure in several South American countries; however, no data are available for Argentina. This study conducted the first screening for LRV1 in the country's most endemic region, Salta Province, analyzing 44 clinical samples from cutaneous, mucosal, and relapsing ATL cases. All samples were identified as Leishmania (Viannia) braziliensis by PCR-RFLP, and tested negative for LRV1 using RT-PCR. Applying a zero-patient design to avoid concluding absolute absence, the theoretical LRV1 prevalence was estimated to be below 7 %, substantially lower than the 25-77 % range reported in Amazonian regions. These findings suggest that LRV1 distribution may not extend into Argentina. While LRV1 may contribute to disease severity when present, it should not be regarded as an exclusive or definitive factor in clinical presentation or therapeutic response in the region. Further research into genetic, immunological, and epidemiological factors is needed to better understand severe ATL forms in Argentina and to develop targeted strategies for improved disease management.},
}

Argentina/epidemiology
Humans
*Leishmania braziliensis/virology/isolation & purification
*Leishmaniavirus/isolation & purification/genetics
Male
Female
*Leishmaniasis, Cutaneous/parasitology/epidemiology
Adult
Middle Aged
Polymorphism, Restriction Fragment Length
Young Adult
Endemic Diseases
Adolescent
Prevalence
Polymerase Chain Reaction

@article {pmid40108258,
year = {2025},
author = {Szymkowiak, P and Konecka, E and Rutkowski, T and Pecyna, A and Szwajkowski, P},
title = {Alien spiders in a palm house with the first report of parthenogenetic Triaeris stenaspis (Araneae: Oonopidae) infected by Wolbachia from new supergroup X.},
journal = {Scientific reports},
volume = {15},
number = {1},
pages = {9512},
pmid = {40108258},
issn = {2045-2322},
mesh = {Animals ; *Spiders/microbiology/physiology ; *Phylogeny ; *Wolbachia/genetics/physiology/classification ; RNA, Ribosomal, 16S/genetics ; Symbiosis ; Poland ; Parthenogenesis ; },
abstract = {Palm houses in Europe serve as urban biodiversity hot spots for alien spiders. As a result of several years of research in the Poznań Palm House, we documented the occurrence of 14 spider species, 9 of which were alien to Europe: Coleosoma floridanum, Hasarius adansoni, Howaia mogera, Ostearius melanopygius, Parasteatoda tabulata, Parasteatoda tepidariorum, Scytodes fusca, Spermophora kerinci and Triaeris stenaspis. The most abundant species was C. floridanum (39.9%). Three spider species were recorded for the first time in Poland: C. floridanum, S. fusca and S. kerinci. We studied the occurrence of endosymbiotic Wolbachia and Cardinium in parthenogenetic T. stenaspis and recorded for the first time the occurrence of Wolbachia in this spider. The endosymbiont was characterized based on the sequences of six bacterial housekeeping genes: 16S rRNA, coxA, fbpA, ftsZ, gatB and hcpA. Our phylogenetic reconstruction of Wolbachia supergroups revealed that the bacteria recovered from the spider formed distinct lineages in relation to all known supergroups. We assigned it to a novel supergroup X with unique sequences within the 16S rRNA and ftsZ genes. We discussed faunistic results in terms of long-term survival rates and the risk of invasion of alien species of spiders.},
}

Animals
*Spiders/microbiology/physiology
*Phylogeny
*Wolbachia/genetics/physiology/classification
RNA, Ribosomal, 16S/genetics
Symbiosis
Poland
Parthenogenesis

@article {pmid40106558,
year = {2025},
author = {Maurya, AK and Kröninger, L and Ehret, G and Bäumers, M and Marson, M and Scheu, S and Nowack, ECM},
title = {A nucleus-encoded dynamin-like protein controls endosymbiont division in the trypanosomatid Angomonas deanei.},
journal = {Science advances},
volume = {11},
number = {12},
pages = {eadp8518},
doi = {10.1126/sciadv.adp8518},
pmid = {40106558},
issn = {2375-2548},
mesh = {*Symbiosis ; *Dynamins/metabolism/genetics ; *Trypanosomatina/genetics/metabolism/microbiology ; Protozoan Proteins/genetics/metabolism ; Cell Nucleus/metabolism ; Cell Division ; Bacterial Proteins/genetics/metabolism ; Cell Cycle/genetics ; },
abstract = {Angomonas deanei is a trypanosomatid of the Strigomonadinae. All members of this subfamily contain a single β-proteobacterial endosymbiont. Intriguingly, cell cycles of host and endosymbiont are synchronized. The molecular mechanisms underlying this notable level of integration are unknown. Previously, we identified a nucleus-encoded dynamin-like protein, called ETP9, that localizes at the endosymbiont division site of A. deanei. Here, we found by comparative genomics that endosymbionts throughout the Strigomonadinae lost the capacity to autonomously form a division septum. We describe the cell cycle-dependent subcellular localization of ETP9 that follows accumulation of the bacterium-encoded division protein FtsZ at the endosymbiont division site. Furthermore, we found that ETP9 is essential in symbiotic but dispensable in aposymbiotic A. deanei that lost the endosymbiont. In the symbiotic strain, ETP9 knockdowns resulted in filamentous, division-impaired endosymbionts. Our work unveiled that in A. deanei an endosymbiont division machinery of dual genetic origin evolved in which a neo-functionalized host protein compensates for losses of endosymbiont division genes.},
}

*Symbiosis
*Dynamins/metabolism/genetics
*Trypanosomatina/genetics/metabolism/microbiology
Protozoan Proteins/genetics/metabolism
Cell Nucleus/metabolism
Cell Division
Bacterial Proteins/genetics/metabolism
Cell Cycle/genetics

@article {pmid40101296,
year = {2025},
author = {Ohm, JR and Lynd, A and McGowan, A and Cupid, A and Bellot, V and Le, JQ and Kakani, E and Livni, J and Crawford, JE and White, BJ},
title = {Mark-Release-Recapture of Packed and Shipped Aedes aegypti with Wolbachia: Implications for Conducting Remote Incompatible Insect Technique Programs.},
journal = {The American journal of tropical medicine and hygiene},
volume = {},
number = {},
pages = {},
doi = {10.4269/ajtmh.24-0262},
pmid = {40101296},
issn = {1476-1645},
abstract = {Male mosquitoes containing the endosymbiont Wolbachia (Wb+) can be used as a tool to suppress wild mosquito populations through a technique termed incompatible insect technique (IIT). IIT programs reduce wild mosquitoes via incompatible matings between released males and wild females to reduce the number of viable offspring produced in the next generation. Successful programs rely on regular release of incompatible males to outcompete wild males for female mates. Past IIT programs have relied on local production of Wb+ males to support regular releases of incompatible males. Here, we evaluated the survival and dispersal of packed and shipped Wb+ Aedes aegypti males in mark-release-recapture studies at a release site in the British Virgin Islands (BVI), separated by over 3,600 miles from the centralized production facility. Released mosquitoes were recaptured using BG-Sentinel 2 traps collected daily for up to 7 days after release. Wb+ male mosquitoes packed and shipped from a centralized production facility performed similarly to males that were locally reared in the BVI in survival, dispersal, and recapture rates. Our results support the conclusion that packing and shipping live Wb+ male mosquitoes does not impact their ability to survive and disperse in release sites and suggests that IIT mosquito control programs can feasibly be conducted nearly anywhere in the world without the need for local mosquito production facilities.},
}

@article {pmid40085262,
year = {2025},
author = {Castelli, M and Petroni, G},
title = {An Evolutionary-Focused Review of the Holosporales (Alphaproteobacteria): Diversity, Host Interactions, and Taxonomic Re-ranking as Holosporineae Subord. Nov.},
journal = {Microbial ecology},
volume = {88},
number = {1},
pages = {15},
pmid = {40085262},
issn = {1432-184X},
mesh = {*Phylogeny ; Animals ; *Alphaproteobacteria/genetics/classification/isolation & purification ; Biological Evolution ; Biodiversity ; },
abstract = {The order Holosporales is a broad and ancient lineage of bacteria obligatorily associated with eukaryotic hosts, mostly protists. Significantly, this is similar to other evolutionary distinct bacterial lineages (e.g. Rickettsiales and Chlamydiae). Here, we provide a detailed and comprehensive account on the current knowledge on the Holosporales. First, acknowledging the up-to-date phylogenetic reconstructions and recent nomenclatural proposals, we reevaluate their taxonomy, thus re-ranking them as a suborder, i.e. Holosporineae, within the order Rhodospirillales. Then, we examine the phylogenetic diversity of the Holosporineae, presenting the 20 described genera and many yet undescribed sub-lineages, as well as the variety of the respective environments of provenance and hosts, which belong to several different eukaryotic supergroups. Noteworthy representatives of the Holosporineae are the infectious intranuclear Holospora, the host manipulator 'Caedimonas', and the farmed shrimp pathogen 'Candidatus Hepatobacter'. Next, we put these bacteria in the broad context of the whole Holosporineae, by comparing with the available data on the least studied representatives, including genome sequences. Accordingly, we reason on the most probable evolutionary trajectories for host interactions, host specificity, and emergence of potential pathogens in aquaculture and possibly humans, as well as on future research directions to investigate those many open points on the Holosporineae.},
}

*Phylogeny
Animals
*Alphaproteobacteria/genetics/classification/isolation & purification
Biological Evolution
Biodiversity

@article {pmid40084540,
year = {2025},
author = {Detcharoen, M and Nilsai, A and Thaochan, N and Nuansuwon, C},
title = {Low Wolbachia incidence in Bactrocera and Zeugodacus species from Thailand and genome analysis of Wolbachia associated with Zeugodacus apicalis.},
journal = {Journal of economic entomology},
volume = {},
number = {},
pages = {},
doi = {10.1093/jee/toaf054},
pmid = {40084540},
issn = {1938-291X},
support = {SCI6402027S//Prince of Songkla University/ ; },
abstract = {Wolbachia are bacterial endosymbionts found widely in arthropods and filarial nematodes. Infecting about half of all arthropod species, Wolbachia manipulate their hosts in various ways, including cytoplasmic incompatibility. Here, we investigated Wolbachia diversity in Bactrocera and Zeugodacus, two prevalent tephritid fruit fly genera, using molecular methods. Wolbachia was only detected in Zeugodacus apicalis (de Meijere) (Diptera: Tephritidae) and not in the other 7 studied species. This newly discovered strain, named wZap, belongs to supergroup B with a 1.3 Mb genome containing 1,248 genes. Phylogenetic analysis of its cytoplasmic incompatibility factor genes cifA and cifB revealed their placement within the Type I clade. Given the presence of cif genes in the wZap genome, further research into their roles in fruit flies could be crucial for developing pest control strategies that exploit CI mechanisms.},
}

@article {pmid40081327,
year = {2025},
author = {Kemen, A and Kemen, E},
title = {Boosting endosymbiosis in plants for future self-sustained crop production.},
journal = {Cell host & microbe},
volume = {33},
number = {3},
pages = {315-318},
doi = {10.1016/j.chom.2025.02.011},
pmid = {40081327},
issn = {1934-6069},
mesh = {*Symbiosis ; *Crops, Agricultural/microbiology/genetics ; *Plant Roots/microbiology ; Calcium Signaling ; Flavonoids/metabolism ; Crop Production ; Calcium/metabolism ; },
abstract = {In a recent article in Nature, Cook et al. demonstrate that an autoactive mutant of CNGC15 generates continuous low-frequency calcium (Ca[2+]) oscillations, enabling sustained flavonoid production and promoting endosymbiont attraction and root colonization. The mutant simultaneously enables endosymbiosis gene induction, even under high-nutrient conditions, offering avenues for improving crop-microbe interactions in agriculture.},
}

*Symbiosis
*Crops, Agricultural/microbiology/genetics
*Plant Roots/microbiology
Calcium Signaling
Flavonoids/metabolism
Crop Production
Calcium/metabolism