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PubMed2026

Comparative analysis of olfactory receptor repertoires reveals evolutionary dynamics and high-altitude adaptation in Schizopygopsis younghusbandi based on the chromosome-level genomes.

The olfactory receptor (OR) gene represent a significant multigene family in vertebrates, forming the core molecular basis of olfactory perception and playing a crucial role in the environmental adaptation of species. High-altitude ecosystems represent extreme habitats characterized by specific abiotic stresses, including low oxygen levels, low temperatures, and intense ultraviolet radiation. These environments also exhibit low aquatic biodiversity and a limited variety of odor molecules, factors that have influenced the adaptive evolution of the sensory systems in endemic species. However, the genetic mechanisms underlying olfactory adaptation in high-altitude freshwater fish remained inadequately understood. In this study, we performed comparative genomics analyses to reveal the evolutionary processes underlying the adaptive and functional evolution of OR genes in S. younghusbandi, a cyprinid fish endemic to the Qinghai-Xizang Plateau. The results indicated that, compared to their low-altitude relatives, S. younghusbandi possessed a significantly smaller number of OR genes, with only 98 genes, which revealed the contraction of the gene family. Phylogenetic analysis revealed that the OR genes of cyprinid fish could be categorized into two major lineages: type I and type II. The η and δ families, which perceive water-soluble odors, in S. younghusbandi underwent significant and specific expansion, while the ε family was completely absent. This pattern reflected adaptive changes in olfactory recognition to accommodate the simplified odor spectrum of high-altitude water bodies. Chromosomal localization analysis demonstrated that OR genes were clustered, and collinearity analysis confirmed the presence of conserved genomic fragments among species. Selection pressure analysis revealed that the Ka/Ks values of all homologous gene pairs were less than 1, indicating that the OR genes of S. younghusbandi underwent strong purifying selection as a group to preserve core olfactory function. A few genes exhibited relaxed selection characteristics, which may have facilitated the fine-tuning of adaptability to high-altitude environments. In conclusion, this study elucidated the evolutionary dynamics and adaptive characteristics of the OR gene in S. younghusbandi, offering a new perspective on the molecular mechanisms underlying olfactory adaptation at high altitudes and enriching the research on sensory evolution in vertebrates.

Schizopygopsis younghusbandi↗

PubMed2025

Migration strategies, connectivity and corridor features of the partial migrant little bustard (Tetrax tetrax) across the Iberian Peninsula.

The study of migration ecology is crucial for understanding the factors and pressures affecting migratory species. Here, we studied the migratory ecology of the little bustard (Tetrax tetrax), a steppe bird that has suffered a sharp decline over recent decades, mainly due to agricultural intensification. Using 105 adult birds tagged across the main Iberian regions where the species is present (Alentejo, Extremadura, Ebro Valley, Northern Plateau, Southern Plateau and Guadalquivir Valley), we analysed the ratio of migratory and resident birds in each population and assessed their connectivity during the three main migratory periods (summer, winter and pre-breeding). Additionally, we describe the features of the migrations recorded in terms of length, duration and day period. Our results corroborate that little bustards can be considered partial migrants across Iberia, although the proportion of residents versus migrants varied between populations: the Alentejo (94.74%) and Northern Plateau (93.75%) had the highest proportion of migrants, followed by Guadalquivir Valley (81.82%), Extremadura (65.38%), Southern Plateau (55.56%) and Ebro Valley (25.93%). Migratory connectivity varied between periods: the pre-breeding and summering migrations showed a trend to move northwards, while birds moved southwards for winter. Regarding the migratory corridors obtained from the 253 migrations identified, we found three main routes: one corridor that connects the Northern Plateau with the western part of the Southern Plateau and Extremadura, another one that connects the Southern Plateau, Extremadura, Alentejo and Guadalquivir Valley, and one corridor that concentrates migrations within the Ebro Valley, and between the Ebro Valley and the Southern Plateau. Finally, analyses showed that little bustards migrate at night through areas dominated by herbaceous cover (avoiding tree-covered land and water bodies) and of low elevation and terrain roughness. Our results highlight the importance of developing an international and inter-regional conservation strategy to protect not only the breeding and wintering quarters, but also this endangered species' migratory corridors, thus supporting the viability of the metapopulation.

Brownian bridge kernel↗

PubMed2026

Vibrio limimangrovi sp. nov., Vibrio phycocola sp. nov. and Vibrio sediminis sp. nov., isolated from coastal habitats.

Four marine bacterial strains of the genus Vibrio, designated WJH972T, RC27, FJH11T, and HA2012T, were isolated from coastal habitats in China. Phenotypic and physiological characterization showed that all four strains are Gram-stain-negative, facultatively anaerobic, short rod-shaped cells, and motile. The 16S rRNA gene sequence similarities between the isolates and their closest relatives were 96.5% - 98.2%, above the genus-level threshold but below the species delineation cutoff. Genomic analysis revealed that strains WJH972T and RC27 shared an average nucleotide identity (ANI) of 98.7% and a digital DNA-DNA hybridization (dDDH) value of 89.9%, confirming their conspecificity. In contrast, the ANI and dDDH values between the four strains and known Vibrio species ranged from 78.6% to 85.8% and from 13.7% to 59.3%, respectively, both falling below the thresholds for species delineation. The biosynthetic gene clusters support bacterial potentials for stress tolerance and antibiotic synthesis, consistent with strain FJH11T's resistance to all 20 antibiotics and other strains' sensitivity to chloramphenicol and penicillin. Based on these polyphasic taxonomic evidence above, three novel species are thus proposed: Vibrio limimangrovi sp. nov. (type strain FJH11T), Vibrio phycocola sp. nov. (type strain WJH972T), and Vibrio sediminis sp. nov. (type strain HA2012T). This study provides novel insights into the systematics, metabolic diversity, antibiotic resistance, and ecological distribution of the genus Vibrio.

Vibrio↗

PubMed2024

Temporal analysis of genetic diversity and gene flow in the threatened catfish Pseudoplatystoma magdaleniatum from a dammed neotropical river.

The striped catfish Pseudoplatystoma magdaleniatum is a large-sized migratory species from the north Andes region, endemic to Magdalena basin and one of the major fishery resources. Despite the estimated reduction of over 80% of the fisheries production of this species throughout the basin in recent decades, its population in the lower Magdalena-Cauca basin showed healthy genetics after molecular analyses. However, the current conservation status of this species and several habitat disturbances demand the re-evaluation of its population genetics to infer evolutionary risks and assess potential changes. This work analyzed a total of 164 samples from the Cauca River collected downstream the Ituango Dam between 2019-2021 using species-specific microsatellite markers to compare the genetic diversity and structure in samples collected between 2010-2014 from the lower Magdalena-Cauca basin, previously analyzed. Our results showed a relatively stable panmictic population over time (4 to 10 years), with high genetic diversity and evidence of recent bottleneck. Promoting habitat connectivity to conserve gene flow, characterizing diversity and genetic structure over the entire basin, and integrating the results with future monitoring are important aspects for the management planning for P. magdaleniatum in the Magdalena-Cauca basin.

Animals↗

PubMed2026

Phylogenetic Constraints and Environmental Filtering Jointly Drive Adaptive Evolution in Phragmites australis: From Genetic Structure to Trait Decoupling on the Mongolian Plateau.

The Mongolian Plateau, a typical arid and semi-arid zone in Eurasia, is characterized by highly heterogeneous and fragmented wetland habitats. Phragmites australis, a common wetland species in this region, exhibits remarkable adaptability. Unraveling the coordination between phylogenetic history and local environmental filtering is crucial for elucidating its adaptive mechanisms. Integrating landscape genomics and trait-based phylogenetic analyses, we analyzed transcriptome-wide SNPs, multidimensional functional traits, and environmental variables across 90 individuals from 30 natural P. australis populations. This study aims to reveal the genetic and phenotypic variation patterns underlying population genetic structure and trait variation, specifically distinguishing the roles of geographic isolation, environmental filtering, and phylogenetic history. Results reveal a significant drainage-dependent pattern in genetic structure. Populations in hydrologically connected basins show extensive admixture, whereas those in isolated endorheic basins form distinct lineages. While geographic isolation underpins genetic differentiation, environmental filtering independently explains ~33.84% of the genetic variation, driven primarily by moisture heterogeneity (precipitation seasonality and soil moisture). Crucially, we observed differentiated evolutionary trajectories across functional traits. Structural traits (e.g., plant height, leaf thickness) are phylogenetically conserved; in contrast, physiological traits (e.g., water use efficiency) are decoupled from phylogeny, showing patterns consistent with high plasticity regulated by local environments. This evolutionary decoupling strategy enables P. australis to flexibly adapt to heterogeneous habitats while maintaining structural stability. This study uncovers the synergistic mechanisms by which geographic isolation and environmental filtering jointly shape the genetic patterns of this cosmopolitan species at a regional scale, clarifies that its evolutionary responses may depend heavily on the differentiated plasticity of trait types, and provides valuable regional insights into how widespread wetland species adapt to heterogeneous environments under global change.

Mongolia Plateau↗

PubMed2026

Unraveling the coastal marine plastisphere archaeome.

Plastic pollution has created an expanding anthropogenic microbial niche, the plastisphere, raising questions about microbial ecology and associated impacts. Archaea, the third domain of life with fundamental ecological and evolutionary significance, remain poorly understood in this habitat. Here, using paired plastic debris and bulk-water samples from coastal marine ecosystems, key archaeal habitats increasingly threatened by plastic pollution, we characterize the plastisphere archaeome through archaeal amplicon sequencing and metagenomics. We show that the archaeome is significantly reshaped in the plastisphere, exhibiting higher taxonomic diversity, greater community heterogeneity, and selective enrichment of Euryarchaeota and Crenarchaeota. Archaeal genes involved in methane, nitrogen, and sulfur cycling are enriched in the plastisphere. Taxonomic and functional divergence between the plastisphere and bulk water increases with anthropogenic chemical stress. These findings suggest that plastic pollution could alter marine archaeal diversity, biogeography, and biogeochemical potential, extending understanding of plastisphere impacts to the archaeal domain.

Archaea↗

PubMed2026

Operationalizing Local Ecological Knowledge for Aquatic Biodiversity Conservation: A Systematic Review and Management Framework.

Effective conservation and management of aquatic biodiversity is severely constrained by the absence of long-term ecological data in small-scale, tropical, and data-poor fisheries, where roughly one-quarter to one-third of freshwater fish species and 37.5% of elasmobranchs are threatened with extinction once Data Deficient species are accounted for. Conventional monitoring and stock-assessment tools are often financially and technically inaccessible in these systems, leaving managers without the evidence needed to prioritize conservation action or implement precautionary governance. Local Ecological Knowledge (LEK) is a largely underutilized resource for natural resource management that can provide temporal depth, spatial resolution, and species-specific ecological insights unavailable from scientific records. We conducted a systematic review and bibliometric synthesis of 60 peer-reviewed studies (1997-2025) applying LEK to assess fish conservation status, examining how, where, and through what methods this knowledge has been used. Our analysis identifies four complementary pathways through which LEK informs conservation management: reconstructing multi-decadal population changes, documenting spatial contraction and habitat loss, detecting extreme rarity and local extirpation, and characterizing intrinsic sensitivity to exploitation based on life-history traits. Despite growing methodological rigor, freshwater systems and African fisheries remain critically underrepresented, and formal integration of LEK into fisheries governance and biodiversity assessment remains the exception rather than the rule. We propose a practical three-stage framework to operationalize LEK within existing management and conservation systems. Recognizing fishing communities as legitimate co-producers of ecological knowledge is both scientifically necessary and an equity imperative for achieving global biodiversity commitments under the Kunming-Montreal Global Biodiversity Framework.

Biodiversity↗

PubMed1978

Spontaneous infectious diseases of marmosets.

The various species of marmosets are susceptible to a wide variety of infectious agents of which only a few have been fully characterized. Little is known concerning spontaneous disease in their natural habitat, and often deaths in the laboratory go unexplained. In captivity, Herpesvirus-T infection appears to be the most important viral infection, but serious disease may also follow infection with measles virus (rubeola) and an unidentified paramyxovirus. Bacterial diseases are multiple, but rarely occur as epizootics. Various species of Salmonella, Yersinia, Klebsiella, and Diplococcus are among the more frequent pathogens. Mycoses and parasitic infections are also numerous, but most do not result in major losses.

Animals↗

PubMed2026

Thermophilic bacteria of the Arabian Gulf and their emerging biotechnological applications: current insights and future prospects.

Thermophilic bacteria represent a powerful class of extremophiles whose ability to thrive at elevated temperatures makes them indispensable to modern biotechnology. The Arabian Gulf characterized by extreme heat, geothermal systems, hot springs, oil reservoirs, and hypersaline habitats hosts a rich yet understudied reservoir of these organisms. This review consolidates current insights into the diversity, ecological niches, and biotechnological relevance of thermophilic bacteria isolated from the region. Dominant genera such as Bacillus, Geobacillus, Thermus, Anoxybacillus, and Brevibacillus exhibit remarkable physiological and molecular strategies that enable survival under intense thermal, saline, and pH stress. Their capacity to produce thermostable enzymes, including proteases, amylases, lipases, cellulases, and DNA polymerases, positions them as high-value contributors to sectors spanning bioenergy, pharmaceuticals, food processing, agriculture, and environmental remediation. Beyond enzyme production, emerging applications such as antimicrobial compound discovery, hydrocarbon bioremediation, wastewater treatment, and sustainable bioprocessing highlight the region's untapped biotechnological potential. However, systematic exploration remains limited, hindered by sparse isolation efforts, incomplete physiological profiling, and a lack of genomic and omics-driven studies. The review underscores the need for integrated approaches that merge classical microbiology with advanced molecular and systems-level tools. Collectively, thermophilic bacteria from the Arabian Gulf constitute a promising yet underutilized biological resource poised to drive sustainable industrial innovation and environmental solutions.

Arabian Gulf↗

PubMed2026

Metatranscriptomic analysis of viral sequences associated with Culex nigripalpus at an Alabama aquaculture site.

Mosquitoes associated with aquaculture habitats can harbor diverse viruses, yet the viromes of many locally abundant species remain poorly characterized. At an aquaculture-associated site in Auburn, Alabama, we surveyed mosquito populations and found Culex nigripalpus to be the dominant species collected. To characterize viruses associated with this mosquito, we performed RNA-seq on pooled female Cx. nigripalpus and compared complementary bioinformatic workflows for viral detection and genome recovery. One workflow removed host-associated reads by mapping to the closest available mosquito reference genome prior to assembly, whereas a second workflow used fully de novo assembly and viral database annotation. Additional protein-level filtering, cross-workflow comparison, and comparison of Trinity and rnaSPAdes assemblies were used to prioritize well-supported viral candidates. Across the original analyses, 16 submitted accessions corresponding to 12 collapsed virus/name groups were recovered, including Merida virus, Hubei mosquito virus 5, Zhejiang mosquito virus, Hubei virga-like virus 3, Rinkaby virus, Elemess virus, Qingnian mosquito virus, Serbia narna-like virus 2, XiangYun narna-levi-like virus 8, Ecclesville picorna-like virus, and baculovirus-like fragments. Several candidates were supported across multiple workflows, while others were recovered only under specific analytical conditions, indicating that candidate recovery was influenced by assembly and filtering choices. Selected viral contigs were independently supported by RT-PCR amplification. Overall, these results provide a first characterization of viral sequences associated with Cx. nigripalpus from an Alabama aquaculture-associated site and show that comparison across assembly and filtering strategies helped prioritize the most consistently supported viral candidates.

Animals↗

PubMed2026

Boreal and subarctic freshwaters harbour a diversity of jumbophages.

Bacteriophages (phages) are major drivers of microbial evolution and ecology, yet their diversity and functional roles remain poorly characterized in many natural environments, such as in freshwater systems. In boreal and subarctic freshwater habitats, where bacteria are typically slow-growing and nutrient-limited, phages are predicted to have a critical role in host regulation and horizontal gene exchange. However, only a few isolates have been obtained from such environments, leaving the genetic and functional diversity of these phages largely unexplored. Here, we present a collection of 40 bacteriophages isolated from boreal lakes and rivers using a set of diverse freshwater bacterial hosts. Despite using conventional isolation methods, eight of the isolates possess genomes larger than 200 kilobases and are classified as jumbophages. All jumbophages exhibited myovirus morphology and comparatively slow infection dynamics. These jumbophages include the first known representatives infecting members of Janthinobacterium and Herbaspirillum. Comparative genomic and phylogenetic analyses show that nearly all genomes are distinct from previously described phages, indicating substantial novelty. Diverse auxiliary metabolic and anti-defence systems were identified, including putative NAD+ salvage and acyl carrier protein modules, along with predicted Anti-Thoeris and Anti-CBASS elements. The Pseudomonas-infecting jumbophage Ahti encoded homologues of all 21 core genes that define the nucleus-forming family Chimalliviridae. Additionally, Ahti displayed compartmentalization of DNA during infection, establishing it as the first freshwater nucleus-forming phage. These findings expand our understanding of the ecological, genomic, and functional diversity of phages in boreal environments and highlight the role of freshwater ecosystems as significant reservoirs of novel viral lineages.

anti-defence systems↗

PubMed2026

Development and Characterization of Microsatellite Markers for the Euryhaline Polychaete Laeonereis acuta (Annelida: Nereididae) in the Southwestern Brazilian Coast.

Laeonereis acuta is a polychaete species typically found at high abundance in estuarine and coastal lagoon environments. Due to its association with polluted habitats, it is commonly used in ecotoxicological studies. Moreover, its occurrence in spatially discontinuous environments with high environmental variability makes it a suitable model for evolutionary studies of local adaptation, genetic landscape, and early stages of speciation. This study aimed to develop primers and characterize microsatellite markers for L. acuta sampled from three coastal lagoons in southwestern Brazil. A total of 10 loci were characterized based on the genotyping of 40 individuals. The number of alleles per locus ranged from 2 to 19. Evidence of null alleles was detected at five loci, although their frequency decreased when coastal lagoons were analyzed separately. When considering all individuals as a single population, five loci showed positive and significant FIS values, and seven loci deviated from Hardy-Weinberg equilibrium. Maricá and Guarapina exhibited heterozygote excess at several loci, whereas Jaconé showed evidence of population genetic isolation. The 10 microsatellite loci were polymorphic and suitable for population genetic analysis in L. acuta, although these patterns may not necessarily be representative of other geographic regions. These markers may contribute to ecotoxicological studies by clarifying whether physiological responses to pollutants are associated with genetic differentiation among populations. Furthermore, they provide valuable tools for investigating genetic structure and connectivity in discontinuous environments.

Animals↗

PubMed2026

Landscape of retron diversity across the SPIRE microbial metagenome resource reveals candidate novel type XI-like lineages.

Retrons are bacterial genetic elements encoding a specialized reverse transcriptase (RT) that synthesizes multicopy single-stranded DNA and are increasingly recognized as components of bacterial anti-phage defense systems. However, their diversity and ecological distribution across large-scale genomic resources remain poorly characterized. Here, we surveyed retron RTs across the SPIRE representative metagenome collection, a non-redundant, species-level data set spanning diverse microbial habitats. Using a curated panel of type-specific hidden Markov models, we identified retrons representing all canonical types together with additional divergent lineages. Retron distribution showed strong taxonomic and ecological structuring, with some groups restricted to specific bacterial phyla, whereas others were broadly distributed across environmental categories. Systematic novelty assessment identified two candidate type XI-like lineages, TXI_C2like and TXI_noncan_h, characterized by protease-independent architectures and distinct accessory modules associated with WYL- and DnaB_C-containing proteins, respectively. De novo covariance-based analyses further identified candidate msr/msd-like non-coding RNA structures in both lineages, supporting conservation of the canonical RT-ncRNA organizational framework despite extensive sequence divergence. Together, these findings expand the known diversity of retron systems and identify type XI-like retrons as a dynamic and previously underexplored evolutionary group.IMPORTANCERetrons are bacterial genetic elements that are increasingly exploited as programmable tools for genome editing, molecular recording, and biosensing in addition to their natural role in anti-phage defense. Despite this growing biotechnological interest, the true diversity of retrons across the bacterial world has remained largely unmapped. By mining a resource of over 100,000 processed microbial metagenomes, we uncovered thousands of retron sequences spanning known types as well as previously unrecognized lineages and found that their distribution is strongly shaped by both bacterial taxonomy and ecological niche. Among these, we identified two candidate new lineages related to type XI retrons that lack the protease domain typical of this group but instead carry distinct accessory proteins, expanding the known architectural diversity of these systems. These findings broaden the catalog of retron diversity available for functional characterization and biotechnological engineering and provide a framework for prioritizing candidate lineages for future experimental validation.

effectors↗

PubMed2026

Unveiling microbial communities and biogeochemical cycles in Antarctic colored snow.

Snow cover, the extensive terrestrial habitat in Antarctica, sometimes exhibits vivid coloration, yet the structure and function of its microbial communities remain poorly characterized. Using metagenomic sequencing of red snow (RS) and green snow (GS) from the Fildes Peninsula, we found that bacterial, eukaryotic, and archaeal relative abundances were 85.82%, 13.52% and 0.16%, respectively. β-Diversity differed significantly between RS and GS across these three domains (P < 0.05). Dominant bacterial phyla included Bacteroidota (RS: 62.61%; GS: 38.72%) and Pseudomonadota (RS: 32.80%; GS: 54.10%). Among eukaryotes, Chlorophyta (RS: 58.10%; GS: 52.98%) and Basidiomycota (RS: 14.80%; GS: 8.08%) were prevalent. Nanobdellota dominated archaea, with lower abundance in RS than GS. In the algal community, Sanguina, Gonium and Chloromonas were significantly enriched in red snow, while Chlorella and Micractinium were enriched in green snow (P < 0.05). Marker genes associated with carbon (C), nitrogen (N), phosphorus (P) and sulfur (S) cycles were identified in green and red snow. Aerobic respiration and phosphate regulation were significantly enriched in red snow, while CO oxidation, fermentation, and denitrification were significantly enriched in green snow. Key microbial genera associated with these functional pathways also varied. In the denitrification of red snow, Stutzerimonas was the most abundant genus, while Janthinobacterium was abundant in green snow. Nitrification-related genes were detected only in red snow based on the present metagenomic data. The network of the red snow microbial community was potentially more complex and resistant based on topology, which not only benefited its own long-term survival but might also have potentially influenced the positive feedback effect of snowmelt by maintaining a low-albedo snow surface. This provided an ecological implication under climate warming: the expansion of red snow patches showed the potential to the increase nitrate runoff export, which would affect nitrogen nutrient levels in coastal Antarctic waters. Overall, this study used metagenomics to compare the multidomain (bacteria, archaea and eukaryotes) composition and diversity between red snow and green snow, and directly linked key microbial taxa with functional genes of biogeochemical cycles. This study provided new insights into the biological characteristics and functional potential of Antarctic colored snow.

Snow↗

PubMed2026

Crawling under the radar: Two novel Paulinella species expand knowledge about the ecology and evolution of a primary plastid-containing amoeba lineage.

The genus Paulinella represents a rare, independent case of primary endosymbiosis, providing a unique system to study the early stages of organelle evolution. Here, we expand current understanding of primary plastid endosymbiosis through the discovery and characterization of two novel photosynthetic amoebae, Paulinella marae sp. nov. and Paulinella murrayi sp. nov., isolated from a brackish water habitat in North Carolina, United States. Complete chromatophore genomes and mitochondrial data revealed conserved gene content but notable structural variation, including genome rearrangements and inversion events. Phylogenetic analyses uncovered significant discordance between nuclear and organelle datasets, likely driven by substitution saturation, limited taxon sampling, and differing evolutionary signals across loci. Ecological observations over multiple years indicate that both species are in low abundance but consistently present, and when coupled with hobbyist data, support the hypothesis that photosynthetic Paulinella species are globally distributed yet under-sampled. These results increase known species diversity within the clade from four to six and highlight the importance of integrating field-based observations with genomic approaches. Overall, this work advances Paulinella as a model for studying ongoing primary endosymbiosis, lineage divergence, and the ecological strategies of low-abundance microbial eukaryotes.

Paulinella↗

PubMed2026

First Isolation and Genomic Characterization of BVDV-1c in Przewalski's Gazelle (Procapra przewalskii) from the Qinghai-Tibet Plateau, China.

Przewalski's gazelle (Procapra przewalskii) is an endangered ungulate endemic to the Qinghai-Tibet Plateau of China. Increasing habitat alteration and close contact with domestic livestock have raised concerns about cross-species pathogen transmission, yet infectious disease studies in this species remain limited. To determine the etiology of illness in two deceased gazelles from a conservation facility in Qinghai Province, we screened samples for a panel of pathogens, including Mycoplasma ovipneumoniae, Clostridium perfringens toxin genes, Mannheimia haemolytica, Klebsiella pneumoniae, Mycoplasma capricolum subsp. capripneumoniae, Pasteurella multocida, Peste des petits ruminants virus (PPRV), Bovine viral diarrhea virus (BVDV), and Infectious bovine rhinotracheitis virus (IBRV), using PCR and RT-PCR. BVDV-specific nucleic acids were detected in tissue samples from both individuals, whereas all other targeted pathogens tested negative. The virus was successfully isolated in Madin-Darby Bovine Kidney (MDBK) cells and confirmed by RT-PCR, followed by whole-genome sequencing of the isolate, which was designated QH PSYL 2026. Phylogenetic analysis based on the full-length genome and 5'UTR sequences assigned the isolate to the BVDV-1c subgenotype. Notably, its 5'UTR sequence shared 100% identity with those of local cattle-derived BVDV strains, providing molecular evidence suggestive of an epidemiological linkage between wildlife and livestock. Integrating clinical signs, gross pathology, and laboratory results, the cases were consistent with BVDV infection as the primary presumptive etiology. To our knowledge, this is the first report of BVDV infection, virus isolation, and genomic characterization in Przewalski's gazelle. The detection of a BVDV-1c strain in this endangered species highlights the potential threat that livestock-associated pathogens pose to wildlife on the Qinghai-Tibet Plateau. These findings furnish crucial baseline data for disease surveillance, molecular epidemiology, and conservation management of Przewalski's gazelle and provide valuable scientific evidence for wildlife disease prevention and control in plateau ecosystems.

BVDV-1c↗

PubMed1979

The reproductive ecology of the house mouse.

This paper attempts to integrate the physiological and ecological perspectives of the reproductive biology of the house mouse (Mus musculus). The endeavor is made within a larger context to provide a prototype for mammalian reproductive ecology in general. Specifically, the environmental regulation of the reproduction of Mus musculus is examined in relation to its ecological opportunism and, in particular, in relation to its history of global colonization. House mice can live as commensals of man or under totally feral conditions. Stable, high density, commensal populations are characterized by an insular division of the living space into demeterritories, each dominated by a single male. Feral populations typically are characterized by temporal, spatial, and social instability. Territoriality is improbable under such conditions, particularly given the necessity for large home ranges in most feral habitats. In both feral and commensal populations, however, male aggressiveness promotes the large-scale dispersal of young, all of which are potential colonizers. Of the ten or so environmental factors known to influence reproduction in house mice, seven probably are of routine importance in natural populations: diurnal modulation by daily light:dark cycles; caloric intake; nutrition; extreme temperature; agaonistic stimuli; socio-tactile cues; and priming pheronomes. The last two factors named operate directly on the secretion of luteinizing hormone or prolactin; the others act at many points in the reproductive system. Reproduction in the house mouse seems divorced from photoperiodically induced seasonality; indeed, this species breeds well even in constant darkness. Seasonal breeding may or may not then occur, depending upon dietary considerations, with or without a secondary interaction with variation in ambient temperature. There is no evidence for a dependence upon secondary plant compounds. Some of the effects of priming pheromones that have been observed previously in laboratory mice probably play no meaningful role in wild populations. The remaining pheromonal phenomena can be conceptualized as a single cueing system that has three components: (a) urinary cues of socially dominant males can accelerate ovulation in females, adult or prepubertal; (b) female urinary cues may elevate pheromonal potency in adult males, thereby forming a feedback loop by which the females elicit their own ovulation; and (c) the male's action on prepubertal females can be blocked by urinary cues emanating from other females. When all of the above is viewed in toto, the reproductive biology of the house mouse seems uniquely suited to support ecological opportunism. The relatively few environmental inhibitors of reproduction in this species should enhance the ability of dispersing young to colonize an exceptionally wide variety of habitats and climates...

Animals↗

PubMed2025

Genomic Insights Into Convergent Evolution: Adaptation to Rocky Habitats in Rock-Inhabiting Fungi.

Rock-inhabiting fungi (RIF), obligate colonizers of bare rocks, are primarily distributed across two major phylogenetic classes: Dothideomycetes and Eurotiomycetes. These fungi display striking convergence in morphology and physiology, characterized by meristematic growth, melanized cell walls, and extreme stress tolerance. However, the genomic underpinnings of this adaptive convergence remain poorly understood. Here, through comparative genomic analysis of 9 RIF and 18 non-RIF fungi, we revealed that RIF possess compact, gene-dense genomes marked by contraction of genes involved in nutrient uptake and secondary metabolism, alongside expansions in cell wall biosynthesis, lipid metabolism, and stress-responsive pathways. We identified two genes under positive selection across multiple RIF lineages: Ino80 ATPase (chromatin remodeling) and the ER chaperone BiP (protein folding). Further evidence of convergence was found in the mannosyltransferase Mnn9, a key enzyme in cell wall assembly, where two RIF-specific amino acid substitutions were predicted to enhance protein stability. Additionally, a unique Mnn9-like clade has expanded exclusively in RIF. RNAi-mediated knockdown of an Mnn9-like gene in Rachicladosporium sp. confirmed its role in cell wall mannosylation, osmotic stress response, and the transition from meristematic to filamentous growth. Our findings elucidate a set of common genomic adaptations and highlight the specialized evolution of the Mnn9 family in driving the convergent success of phylogenetically diverse RIF in rocky environments.

Phylogeny↗