School of Energy and Environment and State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, Hong Kong, China; Research Centre for the Oceans and Human Health, City University of Hong Kong Shenzhen Research Institute, Shenzhen, 518057, China.
School of Energy and Environment and State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, Hong Kong, China; Research Centre for the Oceans and Human Health, City University of Hong Kong Shenzhen Research Institute, Shenzhen, 518057, China.
Fish Shellfish Immunol. 2023 Oct;141:109070. doi: 10.1016/j.fsi.2023.109070. Epub 2023 Sep 12.
The physiological and immune functions of fish gills are largely recognized, but their following functional heterogeneity at the single cell scale has been rarely reported. Here, we performed single cell RNA sequencing (scRNA-seq) on the gills of tilapia fish Oreochromis niloticus. We identified a total of 12 cell populations and analyzed their functional heterogeneity. To investigate the physiological function of O. niloticus gills, expression patterns of genes encoding ion transporters were selected from the identified H-ATPase-rich cells (HR cells), Na/K-ATPase-rich cells (NaR cells), and pavement cells. Specific enrichment of ca4a, slc9a1a, and LOC100692482 in the HR cells of O. niloticus gills explained their functions in acid-base regulation. Genes encoding Ca transporters, including atp2b1, LOC100696627, and LOC 100706765, were specifically expressed in the NaR cells. Pavement cells were presumably the main sites responsible for ammonia and urea transports in O. niloticus gills with specific enrichment of Rhbg and LOC100693008, respectively. The expression patterns of the four immune cell subtypes varied greatly, with B cells being enriched with the most immune-related GO terms. KEGG enrichment analysis showed that MAPK signaling pathway was the most enriched pathway among the four types of immune cells in O. niloticus gills. Our results are important in understanding the physiological and immune responses of fish gills at the cellular resolution.
鱼类鳃的生理和免疫功能在很大程度上已得到认可，但它们在单细胞尺度上的后续功能异质性却鲜有报道。在这里，我们对罗非鱼（Oreochromis niloticus）的鳃进行了单细胞 RNA 测序（scRNA-seq）。我们总共鉴定了 12 种细胞群，并分析了它们的功能异质性。为了研究罗非鱼鳃的生理功能，我们从鉴定出的富含 H-ATPase 的细胞（HR 细胞）、富含 Na/K-ATPase 的细胞（NaR 细胞）和扁平细胞中选择了编码离子转运体的基因的表达模式。HR 细胞中 ca4a、slc9a1a 和 LOC100692482 的特异性富集解释了它们在酸碱调节中的功能。编码 Ca 转运体的基因，包括 atp2b1、LOC100696627 和 LOC 100706765，在 NaR 细胞中特异性表达。扁平细胞可能是罗非鱼鳃中氨和尿素转运的主要部位，分别特异性富集 Rhbg 和 LOC100693008。四种免疫细胞亚型的表达模式差异很大，B 细胞富集了最多的与免疫相关的 GO 术语。KEGG 富集分析表明，MAPK 信号通路是罗非鱼鳃中四种免疫细胞中最富集的通路。我们的研究结果对于理解鱼类鳃在细胞分辨率下的生理和免疫反应具有重要意义。
