Data from: Gene expression plasticity as a mechanism of coral adaptation to a variable environment

Local adaptation is ubiquitous, but the molecular mechanisms that give rise to this ecological phenomenon remain largely unknown. A year-long reciprocal transplant of mustard hill coral (Porites astreoides) between a highly environmentally variable inshore habitat and a more stable offshore habitat demonstrated that populations exhibit phenotypic signatures that are consistent with local adaptation. We characterized the genomic basis of this adaptation in both coral hosts and their intracellular symbionts (Symbiodinium sp.) using genome-wide gene expression profiling. Populations differed primarily in their capacity for plasticity: following transplantation to a novel environment, inshore-origin coral expression profiles became significantly more similar to the local population's profiles than those in offshore-origin corals. Furthermore, elevated plasticity of the environmental stress response expression was correlated with lower susceptibility to a natural summer bleaching event, suggesting that plasticity is adaptive in the inshore environment. Our results reveal a novel genomic mechanism of resilience to a variable environment, demonstrating that corals are capable of a more diverse molecular response to stress than previously thought.

局域适应（local adaptation）普遍存在，但驱动这一生态现象的分子机制在很大程度上仍未被阐明。本研究针对芥状丘珊瑚（Porites astreoides）在环境高度波动的近岸生境与相对稳定的远岸生境之间开展了为期一年的互易移植实验，结果显示珊瑚种群展现出与局域适应相符的表型特征。本研究通过全基因组基因表达谱分析，解析了该适应现象在珊瑚宿主及其胞内共生虫黄藻（Symbiodinium sp.）中的基因组基础。种群间的差异主要体现在表型可塑性（phenotypic plasticity）能力上：当被移植至新环境后，源自近岸的珊瑚的基因表达谱与当地种群的表达谱相似程度，显著高于源自远岸的珊瑚。此外，环境应激响应基因表达的可塑性升高，与夏季自然白化事件中的易感性降低呈显著相关，这表明表型可塑性在近岸生境中具有适应性价值。本研究结果揭示了一种应对波动环境的全新基因组抗逆机制，证明珊瑚对胁迫的分子响应能力比此前认知的更为多样。