摘要: Memory enables organisms to encode, store, and retrieve information essential for interacting with and adapting to a dynamic environment. As an internal representation of the external world, memory serves as a crucial bridge between past experiences and future behaviors. However, the brain continuously forms new memories, raising the question of how new memories are integrated without disrupting previously formed ones.

摘要: While variable regions of immunoglobulins are extensively diversified by V(D)J recombination and somatic hypermutation in vertebrates, the constant regions of immunoglobulin heavy chains also utilize certain mechanisms to produce diversity, including class switch recombination(CSR), subclass differentiation, and alternative expression of the same gene. Many species of birds, reptiles, and amphibians express a truncated isoform of immunoglobulin Y(IgY), termed IgY(ΔFc), which lacks the υCH3 and υCH4 domains. In Anseriformes,IgY(ΔFc) arises from alternative transcriptional termination sites within the same υ gene, whereas in some turtles,intact IgY and IgY(ΔFc) are encoded by distinct genes.Different from the previously reported IgY(ΔFc) variants,this study identified a truncated IgY in the snake Elaphe taeniura, characterized by the loss of only a portion of the CH4 domain. Western blotting and liquid chromatographytandem mass spectrometry confirmed that this truncated IgY is generated by post-translational cleavage at N338 within the IgY heavy chain constant(CH) region.Furthermore, both human and snake asparaginyl endopeptidase were shown to cleave snake IgY in vitro.These findings reveal a novel mechanism for the production of shortened IgY forms, demonstrating that the immunoglobulin CH region undergoes diversification through distinct strategies across vertebrates.

摘要: The silver-lipped pearl oyster(Pinctada maxima) is the largest and most commercially valuable pearl-producing oyster, renowned for its ability to generate large, lustrous pearls. This species is a sequential hermaphrodite, with pearl production displaying notable sexual dimorphism.Consequently, understanding the molecular mechanisms governing sex determination and differentiation is crucial for advancing breeding strategies in the pearl oyster industry. To elucidate these mechanisms, this study conducted integrative transcriptomic analyses of P. maxima gonadal tissues using isoform sequencing(Isoseq) and RNA sequencing(RNA-seq). Comparative analysis of ovarian and testicular tissues identified 2 768 differentially expressed genes(DEGs). Gene coexpression network analysis delineated four key modules,including three sex-specific modules and one shared module. Key genes implicated in sex determination and maintenance were identified, including FOXL2, NANOS1, and β-catenin, important for ovarian maintenance, and DMRT, SOX30, FEM1, and FOXJ1, crucial for testicular maintenance. These genes, widely studied in other taxa,were confirmed as hub genes in the sex-related modules of P. maxima. Interestingly, genes within the shared module were significantly enriched in the spliceosome pathway. Alternative splicing analysis highlighted its extensive role in gonadal tissues, with more pronounced activity observed in the testis compared to the ovary.Nearly half(47.83%, 375) of the identified genes undergoing differential alternative splicing(DASGs) also exhibited differential transcript usage(DTUGs), while only 17% of DTUGs overlapped with DEGs. Genes associated with sex differentiation, such as DMRT, β-catenin, and U2AF2, displayed sex-specific and/or sex-biased isoforms.These findings offer novel insights into the molecular basis of sex differentiation in P. maxima, which could inform the development of targeted breeding strategies aimed at sex control, thereby enhancing pearl quality and yield in aquaculture. This study offers a robust molecular foundation for advancing breeding programs and optimizing production in the pearl oyster industry.

摘要: Local cattle breeds play a critical role in breeding programs due to their genetic adaptations to diverse environmental conditions. However, the genomic architecture of local cattle breeds in Kazakhstan remains largely unexplored.This study utilized whole-genome sequencing data from Kazakh cattle to elucidate their genetic composition,uncovering three primary ancestral components:European, Eurasian, and East Asian taurine. The East Asian taurine lineage likely represents the earliest genetic contribution to Kazakh cattle but was largely replaced by subsequent waves of cattle migrations across Eurasia,leaving only a minor genetic signature in the current cattle population. In contrast, Eurasian taurine ancestry predominated in the Alatau and Kazakh local breeds, while the European taurine component was most prevalent in Kazakh white-headed cattle, consistent with their documented breeding history. Kazakh cattle exhibited higher genetic diversity and lower inbreeding coefficients compared to European commercial breeds, reflecting reduced exposure to intense artificial selection. A strong selection signal was identified on chromosome 6 at a locus encompassing PDGFRA, KIT, and KDR, which may be associated with the white-headed pigmentation characteristic of Kazakh white-headed cattle. Additional genes under selection were linked to lipid metabolism(IRS1, PRKG1, and ADCY8), meat production traits(KCNMA1, PDGFRA, HIF1A, and ANTXR1), and dairy production(ATP2B1, DHX15, FUK, NEGR1, CCDC91,COG4, and PTK2B). This study represents the first comprehensive analysis of nuclear genome data from local Kazakh cattle. It highlights the impact of historical cattle migrations across Eurasia on their genetic landscape and identifies key genomic regions under selection. These findings advance our understanding of the evolutionary history of cattle and offer valuable genetic resources for future breeding strategies.

摘要: While viral infections can disturb the host gut microbiome,the dynamic alterations in microbial composition following infection remain poorly characterized. This study identified SRV-8-infected monkeys and classified them into five groups based on infection progression. 16S rRNA amplicon sequencing revealed significant alterations in the relative and inferred absolute abundance of bacterial genera UCG-002, Agathobacter, Coprococcus, and Holdemanella during the early stage of SRV-8 infection,coinciding with provirus formation. These microbial shifts were accompanied by functional modifications in bacterial communities at the same stage. In contrast, ITS amplicon sequencing indicated no significant differences in fungal composition between healthy wild-type and SRV-8-infected monkeys. Spearman correlation analyses demonstrated close interactions between intestinal bacteria and fungi following SRV-8 infection. Additionally, SRV-8 seropositive groups exhibited significantly elevated mRNA expression levels of pro-inflammatory(TNF-α, IFN-γ, IL-1β, and IL-6) and anti-inflammatory(IL-10) cytokine genes, highlighting close associations between inflammatory cytokines and immune responses. Overall, these findings provide a comprehensive characterization of bacterial and fungal microbiota dynamics and inflammatory cytokine responses associated with SRV-8 infection, clarifying the pathobiological mechanisms underlying SRV-8 infection from the perspective of the gut microbiome.

摘要: Advancements in animal behavior quantification methods have driven the development of computational ethology,enabling fully automated behavior analysis. Existing multianimal pose estimation workflows rely on tracking-bydetection frameworks for either bottom-up or top-down approaches, requiring retraining to accommodate diverse animal appearances. This study introduces InteBOMB, an integrated workflow that enhances top-down approaches by incorporating generic object tracking, eliminating the need for prior knowledge of target animals while maintaining broad generalizability. InteBOMB includes two key strategies for tracking and segmentation in laboratory environments and two techniques for pose estimation in natural settings. The “background enhancement” strategy optimizesforeground-backgroundcontrastiveloss,generating more discriminative correlation maps. The“online proofreading” strategy stores human-in-the-loop long-term memory and dynamic short-term memory,enabling adaptive updates to object visual features. The“automated labeling suggestion” technique reuses the visual features saved during tracking to identify representative frames for training set labeling. Additionally,the “joint behavior analysis” technique integrates these features with multimodal data, expanding the latent space for behavior classification and clustering. To evaluate the framework, six datasets of mice and six datasets of nonhuman primates were compiled, covering laboratory and natural scenes. Benchmarking results demonstrated a24% improvement in zero-shot generic tracking and a 21% enhancement in joint latent space performance across datasets, highlighting the effectiveness of this approach in robust, generalizable behavior analysis.

摘要: While the functions of body coloration have been well characterized in many animal taxa, the molecular mechanisms governing its production remain poorly understood. This study investigated the genetic and biochemical basis of yellow body coloration in a mutant form of the Yongzhang golden soft-shelled turtle(YGT, Pelodiscus sinensis), which exhibit a striking yellow phenotype. Comparative pigment analysis revealed that YGTs have significantly lower melanin and higher carotenoid pigmentation compared to atrovirens wild-type turtles(AWTs), while pterin concentrations did not differ between the two groups. Functional validation experiments demonstrated that a single amino acid substitution(I481R)in tyrosinase-related protein 1(tyrp1) plays a pivotal role in the reduction of melanin production in YGTs. Expression of tyrp1 from YGTs and AWTs in A375 cells, in which human tyrp1(htyrp1) function was depleted by CRISPR-Cas9, led to a specific reduction in melanin production in cells expressing the YGT-tyrp1 variant. Moreover, bco1 and bco2, genes negatively associated with carotenoid content,showed reduced expression in YGTs, suggesting that yellow coloration is achieved through a reduction in melanin pigmentation combined with an accumulation of carotenoids. These findings elucidate the molecular basis of yellow body coloration in turtles and enhance our understanding of pigment regulation in vertebrates.

摘要: Probiotic supplementation enhances the abundance of gutassociated Rhodobacteraceae species, critical symbionts contributing to the health and physiological fitness of Litopenaeus vannamei. Understanding the role of Rhodobacteraceae in shaping the shrimp gut microbiota is essential for optimizing probiotic application. This study investigated whether probiotics benefit shrimp health and fitness via the recruitment of Rhodobacteraceae commensals in the gut. Probiotic supplementation significantly enhanced feed conversion efficiency, digestive enzyme activity, and immune responses, thereby promoting shrimp growth. Additionally, probiotics induced pronounced shifts in gut microbial composition, enriched gut Rhodobacteraceae abundance, and reduced community variability, leading to a more stable gut microbiome. Network analysis revealed that the removal of Rhodobacteraceae nodes disrupted gut microbial connectivity more rapidly than the removal of nonRhodobacteraceae nodes, indicating a disproportionate role of Rhodobacteraceae in maintaining network stability.Probiotic supplementation facilitated the migration of Rhodobacteraceae taxa from the aquatic environment to the shrimp gut while reinforcing deterministic selection in gut microbiota assembly. Transcriptomic analysis revealed that up-regulation of amino acid metabolism and NF-κB signaling pathways was positively correlated with Rhodobacteraceae abundance. These findings demonstrate that probiotic supplementation enriches key Rhodobacteraceae taxa, stabilizes gut microbial networks,and enhances host digestive and immune functions,ultimately improving shrimp growth performance. This study provides novel perspectives on the ecological and molecular mechanisms underlying the beneficial effects of probiotics on shrimp fitness.

摘要: The progressive impact of Enterocytozoon hepatopenaei(EHP) infection on gut microbial function in Litopenaeus vannamei remains poorly understood beyond static comparisons between healthy and infected individuals. To close this knowledge gap, metagenomic sequencing was used to characterize the gut microbiomes of normal, long,medium, and short-sized adult shrimp categorized by increasing severity of infection. EHP infection suppressed digestive activity while inducing immune responses compared with healthy shrimp. Increasing infection severity was associated with a gradual decline in gut α-diversity and an expansion of potential pathogens and virulence factors(VFs). In addition, dysbiosis in gut microbiota composition and function, as well as reduced network stability among differential species, intensified with infection severity. Accordingly, we identified 24 EHP-discriminatory species that contributed an overall 83.3% accuracy in diagnosing infection severity without false negatives. Functional pathway analysis revealed significant suppression of metabolic, degradative, and biosynthetic processes in EHP-infected shrimp compared with healthy controls. Among them, map00630 glyoxylate and dicarboxylate metabolism and map00280 valine,leucine and isoleucine degradation were consistently depleted in infected individuals, thereby impairing their digestive function and anti-inflammatory responses.Additionally, EHP infection diversified VFs directly affecting shrimp gut microbiome. These findings support a conceptual model linking EHP pathogenesis to the parasite-gut microbiome-shrimp physiology axis.

摘要: Selective regulation of gene expression across distinct brain regions is crucial for establishing and maintaining subdivision identities. DNA methylation, a key regulator of gene transcription, modulates transcriptional activity through the conversion of 5-methylcytosine(5mC) to 5-hydroxymethylcytosine(5hmC). While DNA methylation is hypothesized to play an essential role in shaping brain identity by influencing gene expression patterns, its direct contribution, especially in primates, remains largely unexplored. This study examined DNA methylation landscapes and transcriptional profiles across four brain regions, including the cortex, cerebellum, striatum, and hippocampus, using samples from 12 rhesus monkeys.The cerebellum exhibited distinct epigenetic and transcriptional signatures, with differentially methylated regions(DMRs) significantly enriched in metabolic pathways. Notably, genes harboring clustered differentially hydroxymethylated regions(DhMRs) overlapped with those implicated in schizophrenia. Moreover, 5mC located1 kb upstream of the ATG start codon was correlated with gene expression and exhibited region-specific associations with 5hmC. These findings provide insights into the coordinated regulation of cerebellum-specific 5mC and5hmC, highlighting their potential roles in defining cerebellar identity and contributing to neuropsychiatric diseases.