摘要: NLRP3 inflammasome activation is pivotal for cytokine secretion and pyroptosis in response to diverse stimuli,playing a crucial role in innate immunity. While extensively studied in mammals, the regulatory mechanisms governing NLRP3 activation in non-mammalian vertebrates remain largely unexplored. Teleosts, as basal vertebrates,represent an ideal model for exploring the evolutionary trajectory of inflammasome regulation. In this study, ABE assays, confocal microscopy, and biochemical analyses were applied to systematically characterize the mechanisms underlying NLRP3 inflammasome in teleosts,using large yellow croakers(Larimichthys crocea, Lc) and zebrafish(Danio rerio, Dr) as representative models. Our findingsrevealedapreviouslyunrecognized palmitoylation-dependent regulatory mechanism essential for teleost NLRP3 activation. Specifically, zDHHC18-mediated palmitoylation at a teleost-specific cysteine residue(C946 in Lc NLRP3, C1037 in Dr NLRP3) was required for the translocation of NLRP3 to the dispersed trans-Golgi network, facilitating its subsequent recruitment to the microtubule-organizing center. This membrane trafficking was crucial for inflammasome assembly and downstream inflammatory responses. These findings provide new insights into the distinct regulatory mechanisms of NLRP3 activation in teleosts, highlighting an evolutionary divergence that contributes to innate immunity adaptation in early vertebrates.

摘要: Assessing the threat status of species in response to global change is critical for biodiversity monitoring and conservation efforts. However, current frameworks, even the IUCN Red List, often neglect critical factors such as genetic diversity and the impacts of climate and land-use changes, hindering effective conservation planning. To address these limitations, we developed an enhanced extinction risk assessment framework using Diploderma lizards as a model. This framework incorporates long-term field surveys, environmental data, and land-use information to predict distributional changes for 10 recently described Diploderma species on the Qinghai-Xizang Plateau, which hold ecological significance but remain underassessed in conservation assessment. By integrating the distribution data and genetically inferred effective population sizes(Ne), we conducted scenario analyses and used a rank-sum approach to calculate Risk ranking scores(RRS) for each species. This approach revealed significant discrepancies with the IUCN Red List assessments. Notably, D. yangi and D. qilin were identified as facing the highest extinction risk. Furthermore, D. vela,D. batangense, D. flaviceps, D. dymondi, D. yulongense,and D. laeviventre, currently classified as “Least Concern”,were found to warrant reclassification as “Vulnerable” due to considerable threat from projected range contractions.Exploring the relationship between morphology and RRS revealed that traits such as snout-vent length and relative tail length could serve as potential predictors of extinction risk, offering preliminary metrics for assessing species vulnerability when comprehensive data are unavailable.This study enhances the precision of extinction risk assessment frameworks and demonstrates their capacity to refine and update risk assessments, especially for lesser-known taxa.

摘要: The proteasome, an evolutionarily conserved proteolytic complex comprising the 20S core particle and 19S regulatory particles, performs both shared and distinct functionsacrossvarioustissuesandorgans.Spermatogenesis, a highly complex developmental process, relies on proteasome activity at multiple stages to regulate protein turnover. In this study, we selected the20S subunit PSMA1 and 19S regulatory subunit PSMD2 to investigate the potential functions of the proteasome in spermatogenesis. Using Psma1-EGFP and Psmd2-mCherry knock-in mouse models, we confirmed the expression of both subunits in all spermatogenic cell types,with pronounced presence in early germ cell development.To further clarify their functional significance, we specifically knocked out Psma1 and Psmd2 in germ cells.Deletion of either PSMA1 or PSMD2 led to disrupted spermatogenesis, characterized by the complete absence of sperm in the epididymis. Subsequent analysis indicated that loss of these proteasome components impaired meiotic initiation. Psma1 and Psmd2 knockout germ cells showed accumulation of DMRT1, a key regulator of mitosis-to-meiosis transition, leading to a reduction in STRA8 levels and consequent disruption of meiosis initiation. This study sheds light on the molecular mechanisms that govern meiotic initiation and identifies potential genes associated with male infertility.

摘要: Pigeons and certain other avian species produce a milklike secretion in their crop sacs to nourish offspring, yet the detailed processes involved are not fully elucidated. This study investigated the crop sacs of 225-day-old unpaired non-lactating male pigeons(MN) and males initiating lactation on the first day after incubation(ML). Using RNA sequencing,ribosomeprofiling,andsingle-cell transcriptome sequencing(scRNA-seq), we identified a significant up-regulation of genes associated with ribosome assembly and protein synthesis in ML compared to MN. Results from scRNA-seq analysis identified 12distinct cell types and 22 clusters, with secretory epithelial cells(SECs) exhibiting marked expression of plasma cell markers, including IGLL1 and MZB1. RNA fluorescence in situ hybridization(RNA FISH) and IgY quantification confirmed the critical role of SECs in producing endogenous IgY during lactation. We propose that fibroblast-derived BAFF signals activate SECs, mimicking B cell transformation and enhancing protein production through the unfolded protein response(UPR). These findings shed light on the cellular dynamics of pigeon milk production and contribute to a broader understanding of avian biology.

摘要: Avian genomes exhibit compact organization and remarkable chromosomal stability. However, the extent and mechanisms by which structural variation in avian genomes differ from those in other vertebrate lineages are poorly explored. This study generated a diploid genome assembly for the golden pheasant(Chrysolophus pictus),a species distinguished by the vibrant plumage of males.Each haploid genome assembly included complete chromosomalmodels,incorporatingall microchromosomes. Analysis revealed extensive tandem amplification of immune-related genes across the smallest microchromosomes(dot chromosomes), with an average copy number of 54. Structural variation between the haploid genomes was primarily shaped by large insertions and deletions(indels), with minimal contributions from inversions or duplications. Approximately 28% of these large indels were associated with recent insertions of transposable elements, despite their typically low activity in bird genomes. Evidence for significant effects of transposable elements on gene expression was minimal.Evolutionary strata on the sex chromosomes were identified, along with a drastic rearrangement of the W chromosome. These analyses of the high-quality diploid genome of the golden pheasant provide valuable insights into the evolutionary patterns of structural variation in avian genomes.

摘要: Somatic cell nuclear transfer(SCNT) has been successfully employed across various mammalian species,yet cloned animals consistently exhibit low pregnancy rates, primarily due to placental abnormalities such as hyperplasia and hypertrophy. This study investigated the involvement of the Hippo signaling pathway in aberrant placentaldevelopmentinSCNT-inducedbovine pregnancies. SCNT-derived cattle exhibited placental hypertrophy, including enlarged abdominal circumference and altered placental cotyledon morphology. RNA sequencing analysis indicated significant dysregulation of Hippo signaling pathway genes in SCNT placentas. Coexpression of YAP1 and CCND1 was observed in cloned blastocysts, placental tissues, and bovine placental mesenchymal stem cells(bPMSCs). Manipulation of YAP1expression demonstrated the capacity to regulate bPMSC proliferation. Experimental assays confirmed the direct binding of YAP1 to CCND1, which subsequently promoted CCND1 expression in bPMSCs. Furthermore, inhibition of CDK6, a downstream target of CCND1, attenuated SCNT bPMSC proliferation. This study identified YAP1 as a key regulatory component within the Hippo signaling pathway that drives placental hyperplasia in cloned cattle through up-regulation of CCND1-CDK6 expression, facilitating cell cycle progression. These findings offer potential avenues for enhancing cloning efficiency, with implications for evolutionary biology and the conservation of valuable germplasm resources.

摘要: Animal adaptation to environmental challenges is a complex process involving intricate interactions between the host genotype and gut microbiome composition. The gut microbiome, highly responsive to external environmental factors, plays a crucial role in host adaptability and may facilitate local adaptation within species. Concurrently, the genetic background of host populations influences gut microbiome composition,highlighting the bidirectional relationship between host and microbiome. Despite this, our understanding of gut microbiome plasticity and its role in host adaptability remains limited, particularly in reptiles. To clarify this issue,we conducted a reciprocal translocation experiment with gravid females of the Qinghai toad-headed lizards(Phrynocephalus vlangalii) between high-altitude(2?600 m a.s.l.) and superhigh-altitude(3?600 m a.s.l.) environments on Dangjin Mountain of the Qinghai-Xizang Plateau,China. One year later, we assessed the phenotypes and gut microbiomes of their offspring. Results revealed significant plasticity in gut microbiome diversity and structure in response to contrasting elevations. Highaltitude conditions increased diversity, and maternal effects appeared to enable high-altitude lizards to maintain elevated diversity when exposed to superhigh-altitude environments. Additionally, superhigh-altitude lizards displayed distinct gut microbiome structures with notable host specificity, potentially linked to their lower growth rates. Overall, these findings underscore the importance of the gut microbiome in facilitating reptilian adaptation to rapid environmental changes across altitudinal gradients.Furthermore, this study provides critical insights into microbial mechanisms underpinning local adaptation and adaptative plasticity, offering a foundation for future research on host-microbiome interactions in evolutionary and ecological contexts.

摘要: Small RNAs(sRNAs) are a class of molecules capable of perceiving environmental changes and exerting posttranscriptional regulation over target gene expression,thereby influencing bacterial virulence and host immune responses. Pseudomonas plecoglossicida is a pathogenic bacterium that poses a significant threat to aquatic animal health. However, the regulatory mechanisms of sRNAs in P. plecoglossicida remain unclear. This study focused on sRNA113, previously identified as a potential regulator of the fliP gene, a key component of the lateral flagellar type III secretion system. To investigate the effects of sRNA113on P. plecoglossicida virulence, as well as its role in regulating pathogenic processes and host immune responses, mutant strains lacking this sRNA were generated and analyzed. Deletion of sRNA113 resulted in the up-regulation of lateral flagellar type III secretion system-related genes in P. plecoglossicida, which enhanced bacterial swarming motility, biofilm formation,and chemotaxis ability in vitro. In vivo infection experiments with pearl gentian grouper revealed that sRNA113 deletion enhanced the pathogenicity of P.plecoglossicida. This heightened virulence was attributed to the up-regulation of genes associated with the lateral flagellar type III secretion system, resulting in higher bacterial loads within host tissues. This amplification of pathogenic activity intensified tissue damage, disrupted immune responses, and impaired the ability of the host to clear infection, ultimately leading to mortality. These findings underscore the critical role of sRNA113 in regulating the virulence of P. plecoglossicida and its interaction with host immune defenses. This study provides a foundation for further exploration of sRNAmediated mechanisms in bacterial pathogenesis and hostpathogen interactions, contributing to a deeper understanding of virulence regulation and immune evasion in aquatic pathogens.

摘要: Polystyrene nanoparticles pose significant toxicological risks to aquatic ecosystems, yet their impact on zebrafish(Danio rerio) embryonic development, particularly erythropoiesis, remains underexplored. This study used single-cell RNA sequencing to comprehensively evaluate the effects of polystyrene nanoparticle exposure on erythropoiesis in zebrafish embryos. In vivo validation experiments corroborated the transcriptomic findings,revealing that polystyrene nanoparticle exposure disrupted erythrocyte differentiation, as evidenced by the decrease in mature erythrocytes and concomitant increase in immature erythrocytes. Additionally, impaired heme synthesis further contributed to the diminished erythrocyte population.These findings underscore the toxic effects of polystyrene nanoparticles on hematopoietic processes, highlighting their potential to compromise organismal health in aquatic environments.

摘要: The amniote pallium, a vital component of the forebrain,exhibits considerable evolutionary divergence across species and mediates diverse functions, including sensory processing, memory formation, and learning. However, the relationships among pallial subregions in different species remain poorly characterized, particularly regarding the identification of homologous neurons and their transcriptional signatures. In this study, we utilized singlenucleus RNA sequencing to examine over 130?000 nuclei from the macaque（Macaca fascicularis） neocortex,complemented by datasets from humans（Homo sapiens）,mice（Mus musculus）, zebra finches（Taeniopygia guttata）,turtles（Chrysemys picta bellii）, and lizards（Pogona vitticeps）,enablingcomprehensivecross-species comparison. Results revealed transcriptomic conservation and species-specific distinctions within the amniote pallium. Notable similarities were observed among cell subtypes, particularly within PVALB⁺ inhibitory neurons,which exhibited species-preferred subtypes. Furthermore,correlations between pallial subregions and several transcription factor candidates were identified, including RARB, DLX2, STAT6, NR3C1, and THRB, with potential regulatory roles in gene expression in mammalian pallial neurons compared to their avian and reptilian counterparts. These results highlight the conserved nature of inhibitory neurons, remarkable regional divergence of excitatory neurons, and species-specific gene expression and regulation in amniote pallial neurons. Collectively,these findings provide valuable insights into the evolutionary dynamics of the amniote pallium.