Shallow-water Mussels (<i>Mytilus galloprovincialis</i>) Adapt to Deep-Sea Environment Through Transcriptomic and Metagenomic Insights

Recent studies have unveiled the deep sea as a rich biosphere, populated by species descended from shallow-water ancestors post-mass extinctions. Research on genomic evolution and microbial symbiosis has shed light on how these species thrive in extreme deep-sea conditions. However, early adaptation stages, particularly the roles of conserved genes and symbiotic microbes, remain inadequately understood. This study examined transcriptomic and microbiome changes in shallow-water mussels <i>Mytilus galloprovincialis</i> exposed to deep-sea conditions at the Site-F cold seep in the South China Sea. Results reveal complex gene expression adjustments in stress response, immune defense, homeostasis, and energy metabolism pathways during adaptation. After 10 days of deep-sea exposure, shallow-water mussels and their microbial communities closely resembled those of native deep-sea mussels, demonstrating host and microbiome convergence in response to adaptive shifts. Notably, methanotrophic bacteria, key symbionts in native deep-sea mussels, emerged as a dominant group in the exposed mussels. Host genes involved in immune recognition and endocytosis correlated significantly with the abundance of these bacteria. Overall, our analyses provide insights into adaptive transcriptional regulation and microbiome dynamics of mussels in deep-sea environments, highlighting the roles of conserved genes and microbial community shifts in adapting to extreme environments.

近期研究揭示，深海乃是一个物种丰富的生物圈，其栖息物种均为大灭绝事件后由浅海祖先演化而来的类群。围绕基因组演化与微生物共生的相关研究，已阐明这些物种如何在极端深海环境中存活繁衍。然而，对于早期适应阶段，尤其是保守基因与共生微生物所发挥的作用，目前仍缺乏足够的认知。本研究以中国南海F位点冷泉（cold seep）处的深海环境为实验条件，对浅海贻贝（Mytilus galloprovincialis）的转录组学（transcriptomics）与微生物组（microbiome）变化展开了检测分析。研究结果显示，在适应过程中，物种在应激响应、免疫防御、稳态（homeostasis）维持以及能量代谢通路中存在复杂的基因表达调控变化。在暴露于深海环境10天后，实验用浅海贻贝及其微生物群落与本土深海贻贝的对应类群高度相似，表明宿主与微生物组在响应适应性转变时出现了趋同演化。值得注意的是，本土深海贻贝的关键共生伙伴——甲烷氧化细菌（methanotrophic bacteria），在暴露实验的贻贝体内成为了优势类群。宿主中参与免疫识别与胞吞作用（endocytosis）的基因，与这类细菌的丰度呈现显著相关性。综上，本研究的分析结果阐明了深海环境中贻贝的适应性转录调控机制与微生物组动态变化，凸显了保守基因与微生物群落转变在物种适应极端环境过程中的关键作用。

搜集汇总

背景与挑战

背景概述

该数据集聚焦于浅水贻贝（Mytilus galloprovincialis）在深海环境中的适应机制，通过转录组和宏基因组学分析揭示了暴露于中国南海冷泉后基因表达和微生物群落的变化。研究发现，暴露10天后浅水贻贝的转录组和微生物组成与原生深海贻贝趋同，甲烷氧化菌成为优势菌群并与宿主免疫基因显著相关，强调了保守基因和微生物群落在极端环境适应中的关键作用。