Zhao Zhe, Huang Shixia, Feng Qilin, Peng Li, Zhao Qiang, Wang Zhijian
Integrative Science Center of Germplasm Creation in Western China (Chongqing) Science City, Southwest University, Chongqing 401329, China.
Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), School of Life Sciences, Southwest University, Chongqing 400715, China.
Int J Mol Sci. 2025 Mar 4;26(5):2265. doi: 10.3390/ijms26052265.
Vitellogenesis in fish represents a critical phase of oogenesis, significantly influencing the nutritional provisioning for oocyte maturation and subsequent offspring development. However, research on the physiological mechanisms governing vitellogenesis at the single-cell level remains limited. In this study, we performed single-nucleus RNA sequencing (snRNA-seq) on the ovaries of Sichuan bream (). We first identified six distinct cell types (germ cells, follicular cells, immune cells, stromal cells, endothelial cells, and epithelial cells) in the ovaries based on typical functional marker genes. Subsequently, we reconstructed the developmental trajectory of germ cells using pseudotime analysis, which describes the transcriptional dynamics of germ cells at various developmental stages. Additionally, we identified transcription factors (TFs) specific to germ cells that exhibit high activity at each developmental stage. Furthermore, we analyzed the genetic functional heterogeneity of germ cells and follicular cells at different developmental stages to elucidate their contributions to vitellogenesis. Finally, cell interaction analysis revealed that germ cells communicate with somatic cells or with each other via multiple receptors and ligands to regulate growth, development, and yolk acquisition. These findings enhance our understanding of the physiological mechanisms underlying vitellogenesis in fish, providing a theoretical foundation for regulating ovarian development in farmed fish.
鱼类的卵黄发生是卵子发生的一个关键阶段，对卵母细胞成熟及后续子代发育的营养供应有重大影响。然而，在单细胞水平上调控卵黄发生的生理机制研究仍然有限。在本研究中，我们对四川鲂卵巢进行了单核RNA测序（snRNA-seq）。我们首先基于典型的功能标记基因在卵巢中鉴定出六种不同的细胞类型（生殖细胞、卵泡细胞、免疫细胞、基质细胞、内皮细胞和上皮细胞）。随后，我们使用拟时间分析重建了生殖细胞的发育轨迹，该分析描述了生殖细胞在各个发育阶段的转录动态。此外，我们鉴定了在每个发育阶段具有高活性的生殖细胞特异性转录因子（TFs）。此外，我们分析了不同发育阶段生殖细胞和卵泡细胞的基因功能异质性，以阐明它们对卵黄发生的贡献。最后，细胞相互作用分析表明，生殖细胞通过多种受体和配体与体细胞或彼此进行通讯，以调节生长、发育和卵黄获取。这些发现加深了我们对鱼类卵黄发生生理机制的理解，为调控养殖鱼类卵巢发育提供了理论基础。
