Zoological Research最新文献

CRISPR/dCas9-mediated epigenetic editing offers a versatile approach for transcriptional regulation without introducing DNA strand breaks. Although this strategy has been explored in a limited number of species, its application in aquatic vertebrates remains largely uncharacterized. In this study, ten-eleven translocation methylcytosine dioxygenase 1 ( tet1) was cloned and molecularly characterized in marine medaka ( Oryzias melastigma). Decitabine treatment identified fibroblast growth factor 2 ( fgf2) as a methylation-sensitive gene, with a regulatory CpG island located within its promoter region. Subsequently, a CRISPR/dCas9-Tet1CD activation system was constructed by fusing the catalytic domain of Tet1 (Tet1CD, Ala1352-Thr2034) to dCas9, enabling locus-specific DNA demethylation. Targeting fgf2, this CRISPR/dCas9-Tet1CD system induced efficient and selective demethylation of the CpG island, resulting in a maximal 2.41-fold increase in fgf2 transcript levels. Whole-genome bisulfite sequencing and transcriptomic analysis confirmed high on-target precision with minimal off-target effects. Epigenetic activation of fgf2 further modulated downstream gene networks associated with growth, promoting durable transcriptional enhancement and increased cellular proliferation. Collectively, these results establish a robust and highly specific epigenetic editing platform in marine medaka, providing a powerful tool for functional genomics studies and regulatory element analysis in aquatic models.

Embryo implantation requires coordinated interactions between the embryo and the maternal endometrium. Endometrial organoids (EOs) have emerged as promising in vitro models for studying this process. At present, however, mouse-derived EOs (mEOs) are predominantly composed of a single epithelial cell type and lack a functional luminal epithelium (LE), cellular diversity, and hormonally responsive architecture, limiting their capacity to recapitulate the dynamic receptive phase of the endometrium. In this study, a robust three-dimensional mouse endometrial assembloid model was established by co-culturing endometrial gland-like organoids (GLOs) with primary endometrial stromal cells (ESCs) under air-liquid interface (ALI) conditions. Optimization of the GLO culture was achieved by fine-tuning the concentrations of Wnt3a and R-Spondin1, while stromal viability and functionality were enhanced by supplementation with hydrocortisone, L-ascorbic acid, and ITS-X. Comparative analysis demonstrated that ALI conditions significantly enhanced epithelial proliferation, gland morphogenesis, and metabolic activity across both epithelial and stromal compartments. Notably, the resulting ALI-grown mouse endometrial assembloids (ALI-mEnAOs) developed a well-defined LE layer and recapitulated molecular and cellular features characteristic of both pre-receptive and receptive endometrial states in vivo. Compared to existing mEOs, analyses confirmed that ALI-mEnAOs closely mimic in vivo endometrial architecture, lineage composition, phase-specific gene expression signatures, and dynamic hormonal response. This model offers a physiologically relevant platform for mechanistic investigation of endometrial function and embryo implantation dynamics.

Neurodegenerative disorders such as Alzheimer's disease are characterized by pathological protein misfolding, persistent neuroinflammation, and progressive synaptic deterioration. Nanoscale therapeutic platforms offer a versatile strategy for simultaneously suppressing pathogenic protein aggregation and modulating glial hyperactivation, thereby addressing the multifactorial nature of neurodegenerative pathology. Engineered AuNPs, carbon-based nanodots, and related constructs with negatively charged surfaces exhibit high affinity for amyloidogenic peptides, thereby limiting amyloid-β or tau fibrillization, while photothermal strategies using graphene or gold nanorods induce localized thermal disruption of preformed aggregates, enhancing their disassembly. In parallel, functionalized nanocarriers facilitate brain-targeted delivery of anti-inflammatory agents by leveraging receptor-mediated transcytosis or biomimetic cell membrane-camouflaging strategies, attenuating proinflammatory cytokines and promoting autophagic clearance. In vitro and in vivo models demonstrate integrated therapeutic benefits, including attenuation of plaque deposition, preservation of neuronal integrity, and recovery of cognitive performance. Despite remaining challenges in large-scale synthesis and long-term safety, evolving nanotechnologies offer a flexible and integrated platform capable of disrupting the pathogenic cycle linking protein misfolding, neuroinflammation, and disease progression.

Pangolins represent the most heavily trafficked mammal globally and harbor diverse microorganisms, raising the concern that illegal trade increases their susceptibility to infectious diseases and facilitates the spread of zoonotic pathogens. In this study, internal organ and fecal samples were collected from 15 confiscated pangolins rescued at the Jinhua Wildlife Rescue Station in Zhejiang Province, China. Metatranscriptomic analysis combined with polymerase chain reaction (PCR) screening detected pestivirus, canine parvovirus 2 (CPV-2), human parainfluenza virus 2 (HPIV2), and Pseudomonas aeruginosa at high abundance in three deceased individuals, while no candidate pathogens were identified in the remaining 12 surviving animals. Two of the deceased pangolins, Pujiang-Pangolin-2 and Pujiang-Pangolin-3, were co-infected with four and two pathogens, respectively, and both exhibited more severe pathological lesions than Qingtian-Pangolin-1, in which only CPV-2 was detected. Pujiang-Pangolin-2 showed markedly elevated levels of CPV-2 and P. aeruginosa in the lung and spleen, accompanied by extensive tissue damage. Pujiang-Pangolin-3 had a higher abundance of pestivirus and presented with pronounced internal hemorrhage. Notably, phylogenetic analyses reveal that the pestivirus, CPV-2, and HPIV2 detected in the infected pangolins were closely related to strains previously identified in Manis javanica, domestic dogs from Vietnam, and humans from the Netherlands, respectively, while the P. aeruginosa sequences clustered with isolates obtained from human clinical samples both within China and internationally.Together with prior reports, these data suggest that trafficked pangolins are highly susceptible to diverse infections and may contribute to the transmission of zoonotic pathogens across species and geographic boundaries.

Mitochondrial genomes (mitogenomes) play a crucial role in species adaptation to diverse evolutionary pressures. Although adaptive changes in mitochondrial genes have been reported under extreme conditions, large-scale analyses of mitogenomic evolution across ecologically diverse habitats are still limited. The Eurasian tree sparrow ( Passer montanus), one of the most widely distributed avian species, occupies variable habitats, providing an ideal model for investigating mitochondrial responses to environmental heterogeneity. This study examined mitogenomic variation in tree sparrow populations sampled across China, revealing pronounced mitochondrial divergence in geographically isolated populations, particularly those in southern Xizang on the Qinghai-Xizang Plateau and the continental islands of Hainan and Taiwan. In the high-altitude population of southern Xizang, non-synonymous substitutions in COX2 and COX3 may enhance protein stability, potentially facilitating adaptation to cold and hypoxic conditions. In contrast, substitutions in ATP6 (Hainan) and ND5 (Taiwan) may reduce protein stability, implying distinct mitogenomic responses to local environmental constraints. Moreover, distinct tRNA mutations in the Hainan populations may confer increased structural flexibility, potentially contributing to island-specific adaptation. These findings highlight the role of mitochondrial genomes in responding to ecological variation and geographic barriers, underscoring the prospective functional consequences of mitogenomic evolution.

Defining developmental periods- and breed-specific cellular features of the porcine kidney is critical for refining donor selection strategies in xenotransplantation. This study utilized single-nucleus RNA sequencing to generate 71 081 high-quality transcriptomes from eight kidneys sampled across three developmental periods-weaning, fattening, and maturity-in Bamaxiang (BMX) and wild boar (WB) breeds. A total of 33 distinct cell types were identified. Proximal tubule (PT), principal (PC), and thick ascending limb (TAL) cells exhibited pronounced transcriptional transitions across developmental periods. PT cells displayed a temporal shift from early development-related functions during the weaning period to metabolic and transport functions during fattening and maturity. Subclustering of PT cells revealed discrete functional subtypes, including a mature WB-specific PT2 cluster enriched in immune function regulation. In PC cells, both breeds expressed a shared PC0 subtype during weaning with signatures of cellular development. The WB-specific PC2 subtype was enriched in thermoregulation pathways, whereas at maturity, the BMX-specific PC0 subtype exhibited transcriptional features associated with oxidative metabolism and the WB-specific PC1 subtype expressed genes involved in glucose metabolism. These findings suggest divergent physiological adaptations to domestication and wild environments. Cell-cell interaction analysis identified the epidermal growth factor (EGF) signaling pathway as the most active across BMX kidney development, with epithelial tubule subtypes engaging in ligand-receptor interactions via ligands, including betacellulin (BTC), EGF, and transforming growth factor-α (TGF-α).

Bacteria, as fundamental members of the microbial biosphere, are under constant threat from mobile genetic elements (MGEs), including bacteriophages and plasmids. In response, diverse molecular defense strategies have emerged to detect, neutralize, and eliminate these invaders. This review provides a comprehensive framework for categorizing known bacterial defense systems based on mechanistic principles and modes of action, alongside a synthesis of core operational themes that underlie their functional diversity. Particular attention is given to evolutionary parallels between bacterial immunity and antiviral mechanisms in eukaryotes, with emphasis on conserved molecular modules that reflect a convergent logic of immune defense across biological domains. Biotechnology platforms harnessing bacterial defense systems are also examined, with a focus on their application across practical domains, including genetic enhancement of crops and livestock, development of molecular diagnostics and precision therapies, and optimization of microbial strains for industrial fermentation. By integrating mechanistic architecture, evolutionary relationships, and translational advances into a coherent framework, this review broadens the conceptual understanding of bacterial immunity and lays the groundwork for its expanded application in both research and biotechnological innovation.

Rodents play a pivotal role in the maintenance and transmission of zoonotic viruses. The Yili River Valley, one of the most biodiverse regions in Xinjiang, functions as a critical biogeographic corridor linking China with Central and Western Asia, and historically with Europe via the ancient Silk Road. Despite its significance, the viral landscape of this region remains largely unexplored. To elucidate the virological landscape of this understudied region, meta-transcriptomic sequencing was conducted on wild rodent samples collected between 2020 and 2023, encompassing multiple host species and tissue types (liver, lung, spleen, and intestine). Analysis identified 18 vertebrate-associated viral families, including several of known zoonotic or evolutionary relevance, such as Arteriviridae, Coronaviridae, Flaviviridae, Hantaviridae, Hepeviridae, Hepadnaviridae, and Picornaviridae. Remarkably, over 80% of the detected viruses represented putative novel species, highlighting the vast and previously undocumented viral diversity harbored by rodents in this region. Viral community composition exhibited clear host- and tissue-specific patterns. Critically, novel rodent-derived arteriviruses (RtArteVs) in Microtus obscurus were identified, exhibiting approximately 86% nucleotide identity with porcine reproductive and respiratory syndrome virus 1 (PRRSV1). Additionally, phylogenetic and recombination analyses support the hypothesis that PRRSV1 emerged through ancestral recombination among divergent RtArteVs, implicating rodents as the likely origin of this economically significant swine pathogen. These findings expand current understanding of rodent viromes in an important biodiversity hotspot, revealing a substantial yet largely uncharted viral diversity. Furthermore, this study underscores the critical need for continued surveillance of viral groups with potential for viral spillover to humans and domestic animals, including Arteriviridae, Flaviviridae, Hantaviridae, Hepeviridae, and Hepadnaviridae.

The term "worm medicines" (Chong Yao) in Traditional Chinese Medicine encompasses a diverse category of small animal-derived therapeutics, including arthropods, amphibians, and reptiles, rather than strictly vermiform organisms. Many of these animals, such as scorpions, centipedes, toads, and horseflies, are toxic, and have been employed in clinical practice for centuries, despite limited understanding of their active compounds and underlying modes of action. Among the bioactive constituents extracted from these taxa, peptides represent a particularly promising class, with over 2 000 identified to date. These peptides are primarily secreted from specialized exocrine glands, including venom, salivary, and cutaneous glands, and are characterized by high structural diversity and target specificity. Their potent modulatory effects on the nervous, cardiovascular, and immune systems make them excellent candidates for drug discovery and development. This review examines peptide-based compounds derived from the exocrine secretions of venomous and poisonous taxa historically employed in traditional Chinese "worm " medicines. Emphasis is placed on their biological origins, structural features, and pharmacological activities, highlighting their significant potential as a rich and largely untapped resource for modern therapeutic discovery.

Gene loss represents a powerful driver of adaptive evolution. Cetaceans, which underwent a profound transition from terrestrial to fully aquatic life, provide an excellent model for investigating this process. Comparative genomic analysis of the cold-sensitive ion channel transient receptor potential ankyrin 1 ( TRPA1) revealed lineage-specific patterns of degeneration across cetaceans. In toothed whales, the ancestral lineage exhibited extensive exon loss within the TRPA1 locus, whereas baleen whales showed signatures consistent with markedly reduced or absent TRPA1 expression. These molecular alterations were inferred to disrupt or abolish TRPA1 protein function across cetaceans. Integration of these findings with established experimental evidence from human and murine TRPA1 studies supported several adaptive hypotheses for TRPA1 gene loss, including tolerance to abrupt thermal fluctuations, attenuation of nociceptive responses in aquatic environments, specialization of integumentary sensory systems, and the emergence of echolocation-associated sensory trade-offs in toothed whales. Collectively, these findings expand the gene loss repertoire of cetaceans and provide novel insights into the molecular underpinnings of secondary aquatic adaptation in mammals.