Data from: Functional genomic analysis of corals from natural CO2-seeps reveals core molecular responses involved in acclimatization to ocean acidification

Little is known about the potential for acclimatization or adaptation of corals to ocean acidification and even less about the molecular mechanisms underpinning these processes. Here we examine global gene expression patterns in corals and their intracellular algal symbionts from two replicate population pairs in Papua New Guinea that have undergone long-term acclimatization to natural variation in pCO2. In the coral host, only 61 genes were differentially expressed in response to pCO2 environment, but the pattern of change was highly consistent between replicate populations, likely reflecting the core expression homeostasis response to ocean acidification. Functional annotations highlight lipid metabolism and a change in the stress response capacity of corals as key parts of this process. Specifically, constitutive downregulation of molecular chaperones was observed, which may impact response to combined climate-change related stressors. Elevated CO2 has been hypothesized to benefit photosynthetic organisms but expression changes of in hospite Symbiodinium in response to acidification were greater and less consistent among reef populations. This population-specific response suggests hosts may need to adapt not only to an acidified environment, but also to changes in their Symbiodinium populations that may not be consistent among environments, adding another challenging dimension to the physiological process of coping with climate change.目前学界对珊瑚适应海洋酸化的驯化或适应潜力尚不明晰，而对支撑这些过程的分子机制的了解更是匮乏。本研究针对巴布亚新几内亚的两对重复珊瑚种群及其胞内藻类共生体的全基因表达模式展开分析，这些种群已长期适应自然pCO2波动。在珊瑚宿主中，仅61个基因对pCO2环境产生差异表达，但重复种群间的表达变化模式高度一致，这可能反映了珊瑚应对海洋酸化的核心表达稳态响应。功能注释结果显示，脂质代谢与珊瑚应激响应能力的改变是该过程的核心环节。具体而言，研究观察到分子伴侣的组成型下调，这可能会影响珊瑚对多种气候变化相关复合胁迫的响应能力。此前有假说认为，CO₂浓度升高会对光合生物产生益处，但宿主体内虫黄藻（Symbiodinium）对酸化的表达响应强度更高，且在珊瑚礁种群间一致性更低。这种种群特异性的响应表明，珊瑚宿主不仅需要适应酸化环境，还需适应其共生虫黄藻种群在不同环境下的不一致变化，这为珊瑚应对气候变化的生理适应过程增添了另一重挑战维度。