Center of Deep-Sea Research, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.
Laboratory for Marine Biology and Biotechnology, Qingdao Marine Science and Technology Center, Laoshan Laboratory, Qingdao, China.
Elife. 2024 Aug 5;12:RP88294. doi: 10.7554/eLife.88294.
Bathymodioline mussels dominate deep-sea methane seep and hydrothermal vent habitats and obtain nutrients and energy primarily through chemosynthetic endosymbiotic bacteria in the bacteriocytes of their gill. However, the molecular mechanisms that orchestrate mussel host-symbiont interactions remain unclear. Here, we constructed a comprehensive cell atlas of the gill in the mussel from the South China Sea methane seeps (1100 m depth) using single-nucleus RNA-sequencing (snRNA-seq) and whole-mount in situ hybridisation. We identified 13 types of cells, including three previously unknown ones, and uncovered unknown tissue heterogeneity. Every cell type has a designated function in supporting the gill's structure and function, creating an optimal environment for chemosynthesis, and effectively acquiring nutrients from the endosymbiotic bacteria. Analysis of snRNA-seq of in situ transplanted mussels clearly showed the shifts in cell state in response to environmental oscillations. Our findings provide insight into the principles of host-symbiont interaction and the bivalves' environmental adaption mechanisms.
贻贝科软体动物主要栖息在深海甲烷渗漏和热液喷口栖息地，通过其鳃部的细菌细胞中的化能合成共生细菌获取营养和能量。然而，协调贻贝宿主-共生体相互作用的分子机制尚不清楚。在这里，我们使用单细胞 RNA 测序 (snRNA-seq) 和全组织原位杂交技术，构建了南海甲烷渗漏区 (水深 1100 米) 贻贝鳃的综合细胞图谱。我们鉴定了 13 种细胞类型，包括三种以前未知的细胞类型，并揭示了未知的组织异质性。每种细胞类型都有特定的功能来支持鳃的结构和功能，为化能合成创造了最佳环境，并有效地从共生细菌中获取营养。对原位移植贻贝的 snRNA-seq 分析清楚地显示了细胞状态对环境波动的响应变化。我们的研究结果为宿主-共生体相互作用的原理和双壳类动物的环境适应机制提供了新的见解。
