Zoological Research最新文献

Litopenaeus vannamei is the most extensively cultured shrimp species globally, recognized for its scale, production, and economic value. However, its aquaculture is plagued by frequent disease outbreaks, resulting in rapid and massive mortality. etiological research often lags behind the emergence of new diseases, leaving the causal agents of some shrimp diseases unidentified and leading to nomenclature based on symptomatic presentations, especially in cases involving co- and polymicrobial pathogens. Comprehensive data on shrimp disease statuses remain limited. In this review, we summarize current knowledge on shrimp diseases and their effects on the gut microbiome. Furthermore, we also propose a workflow integrating primary colonizers, "driver" taxa in gut networks from healthy to diseased states, disease-discriminatory taxa, and virulence genes to identify potential polymicrobial pathogens. We examine both abiotic and biotic factors (e.g., external and internal sources and specific-disease effects) that influence shrimp gut microbiota, with an emphasis on the "holobiome" concept and common features of gut microbiota response to diverse diseases. After excluding the effects of confounding factors, we provide a diagnosis model for quantitatively predicting shrimp disease incidence using disease common-discriminatory taxa, irrespective of the causal agents. Due to the conservation of functional genes used in designing specific primers, we propose a practical strategy applying qPCR-assayed abundances of disease common-discriminatory functional genes. This review updates the roles of the gut microbiota in exploring shrimp etiology, polymicrobial pathogens, and disease incidence, offering a refined perspective for advancing shrimp aquaculture health management.

The mutation rate is a pivotal biological characteristic, intricately governed by natural selection and historically garnering considerable attention. Recent advances in high-throughput sequencing and analytical methodologies have profoundly transformed our understanding in this domain, ushering in an unprecedented era of mutation rate research. This paper aims to provide a comprehensive overview of the key concepts and methodologies frequently employed in the study of mutation rates. It examines various types of mutations, explores the evolutionary dynamics and associated theories, and synthesizes both classical and contemporary hypotheses. Furthermore, this review comprehensively explores recent advances in understanding germline and somatic mutations in animals and offers an overview of experimental methodologies, mutational patterns, molecular mechanisms, and driving forces influencing variations in mutation rates across species and tissues. Finally, it proposes several potential research directions and pressing questions for future investigations.

The tree shrew ( Tupaia belangeri) has long been proposed as a suitable alternative to non-human primates (NHPs) in biomedical and laboratory research due to its close evolutionary relationship with primates. In recent years, significant advances have facilitated tree shrew studies, including the determination of the tree shrew genome, genetic manipulation using spermatogonial stem cells, viral vector-mediated gene delivery, and mapping of the tree shrew brain atlas. However, the limited availability of tree shrews globally remains a substantial challenge in the field. Additionally, determining the key questions best answered using tree shrews constitutes another difficulty. Tree shrew models have historically been used to study hepatitis B virus (HBV) and hepatitis C virus (HCV) infection, myopia, and psychosocial stress-induced depression, with more recent studies focusing on developing animal models for infectious and neurodegenerative diseases. Despite these efforts, the impact of tree shrew models has not yet matched that of rodent or NHP models in biomedical research. This review summarizes the prominent advancements in tree shrew research and reflects on the key biological questions addressed using this model. We emphasize that intensive dedication and robust international collaboration are essential for achieving breakthroughs in tree shrew studies. The use of tree shrews as a unique resource is expected to gain considerable attention with the application of advanced techniques and the development of viable animal models, meeting the increasing demands of life science and biomedical research.

Tumor necrosis factor α (TNFα) exhibits diverse biological functions; however, its regulatory roles in myogenesis are not fully understood. In the present study, we explored the function of TNFα in myoblast proliferation, differentiation, migration, and myotube fusion in primary myoblasts and C2C12 cells. To this end, we constructed TNFα muscle-conditional knockout ( TNFα-CKO) mice and compared them with flox mice to assess the effects of TNFα knockout on skeletal muscles. Results indicated that TNFα-CKO mice displayed phenotypes such as accelerated muscle development, enhanced regenerative capacity, and improved exercise endurance compared to flox mice, with no significant differences observed in major visceral organs or skeletal structure. Using label-free proteomic analysis, we found that TNFα-CKO altered the distribution of several muscle development-related proteins, such as Hira, Casz1, Casp7, Arhgap10, Gas1, Diaph1, Map3k20, Cfl2, and Igf2, in the nucleus and cytoplasm. Gene set enrichment analysis (GSEA) further revealed that TNFα deficiency resulted in positive enrichment in oxidative phosphorylation and MyoD targets and negative enrichment in JAK-STAT signaling. These findings suggest that TNFα-CKO positively regulates muscle growth and development, possibly via these newly identified targets and pathways.

Magnetic sense, or termed magnetoreception, has evolved in a broad range of taxa within the animal kingdom to facilitate orientation and navigation. MagRs, highly conserved A-type iron-sulfur proteins, are widely distributed across all phyla and play essential roles in both magnetoreception and iron-sulfur cluster biogenesis. However, the evolutionary origins and functional diversification of MagRs from their prokaryotic ancestor remain unclear. In this study, MagR sequences from 131 species, ranging from bacteria to humans, were selected for analysis, with 23 representative sequences covering species from prokaryotes to Mollusca, Arthropoda, Osteichthyes, Reptilia, Aves, and mammals chosen for protein expression and purification. Biochemical studies revealed a gradual increase in total iron content in MagRs during evolution. Three types of MagRs were identified, each with distinct iron and/or iron-sulfur cluster binding capacity and protein stability, indicating continuous expansion of the functional roles of MagRs during speciation and evolution. This evolutionary biochemical study provides valuable insights into how evolution shapes the physical and chemical properties of biological molecules such as MagRs and how these properties influence the evolutionary trajectories of MagRs.

General anesthesia is widely applied in clinical practice. However, the precise mechanism of loss of consciousness induced by general anesthetics remains unknown. Here, we measured the dynamics of five neurotransmitters, including γ-aminobutyric acid, glutamate, norepinephrine, acetylcholine, and dopamine, in the medial prefrontal cortex and primary visual cortex of C57BL/6 mice through in vivo fiber photometry and genetically encoded neurotransmitter sensors under anesthesia to reveal the mechanism of general anesthesia from a neurotransmitter perspective. Results revealed that the concentrations of γ-aminobutyric acid, glutamate, norepinephrine, and acetylcholine increased in the cortex during propofol-induced loss of consciousness. Dopamine levels did not change following the hypnotic dose of propofol but increased significantly following surgical doses of propofol anesthesia. Notably, the concentrations of the five neurotransmitters generally decreased during sevoflurane-induced loss of consciousness. Furthermore, the neurotransmitter dynamic networks were not synchronized in the non-anesthesia groups but were highly synchronized in the anesthetic groups. These findings suggest that neurotransmitter dynamic network synchronization may cause anesthetic-induced loss of consciousness.

General anesthetic agents can impact brain function through interactions with neurons and their effects on glial cells. Oligodendrocytes perform essential roles in the central nervous system, including myelin sheath formation, axonal metabolism, and neuroplasticity regulation. They are particularly vulnerable to the effects of general anesthetic agents resulting in impaired proliferation, differentiation, and apoptosis. Neurologists are increasingly interested in the effects of general anesthetic agents on oligodendrocytes. These agents not only act on the surface receptors of oligodendrocytes to elicit neuroinflammation through modulation of signaling pathways, but also disrupt metabolic processes and alter the expression of genes involved in oligodendrocyte development and function. In this review, we summarize the effects of general anesthetic agents on oligodendrocytes. We anticipate that future research will continue to explore these effects and develop strategies to decrease the incidence of adverse reactions associated with the use of general anesthetic agents.

The placenta plays a crucial role in successful mammalian reproduction. Ruminant animals possess a semi-invasive placenta characterized by a highly vascularized structure formed by maternal endometrial caruncles and fetal placental cotyledons, essential for full-term fetal development. The cow placenta harbors at least two trophoblast cell populations: uninucleate (UNC) and binucleate (BNC) cells. However, the limited capacity to elucidate the transcriptomic dynamics of the placental natural environment has resulted in a poor understanding of both the molecular and cellular interactions between trophoblast cells and niches, and the molecular mechanisms governing trophoblast differentiation and functionalization. To fill this knowledge gap, we employed Stereo-seq to map spatial gene expression patterns at near single-cell resolution in the cow placenta at 90 and 130 days of gestation, attaining high-resolution, spatially resolved gene expression profiles. Based on clustering and cell marker gene expression analyses, key transcription factors, including YBX1 and NPAS2, were shown to regulate the heterogeneity of trophoblast cell subpopulations. Cell communication and trajectory analysis provided a framework for understanding cell-cell interactions and the differentiation of trophoblasts into BNCs in the placental microenvironment. Differential analysis of cell trajectories identified a set of genes involved in regulation of trophoblast differentiation. Additionally, spatial modules and co-variant genes that help shape specific tissue structures were identified. Together, these findings provide foundational insights into important biological pathways critical to the placental development and function in cows.