Elevated sea surface temperature associated with global warming is a serious threat to coral reefs. Elevated temperatures directly or indirectly alter the distribution of coral-pathogen interactions and thereby exacerbate infectious coral diseases. The pathogenic bacterium Vibrio coralliilyticus is well-known as a causative agent of infectious coral disease. Rising sea surface temperature promotes the infection of corals by this bacterium, which causes several coral pathologies, such as bacterial bleaching, tissue lysis, and white syndrome. However, the effects of thermal stress on coral immune responses to the pathogen are poorly understood. To delineate the effects of thermal stress on coral immunity, we performed transcriptome analysis of aposymbiotic primary polyps of the reef-building coral Acropora digitifera exposed to V. coralliilyticus under thermal stress conditions. V. coralliilyticus infection of coral that was under thermal stress had negative effects on various molecular processes, including suppression of gene expression related to the innate immune response. In response to the pathogen, the coral mounted various responses including changes in protein metabolism, exosome release delivering signal molecules, extracellular matrix remodeling, and mitochondrial metabolism changes. Based on these results, we provide new insights into innate immunity of A. digitifera against pathogen infection under thermal stress conditions.

与全球变暖有关的海面温度升高是对珊瑚礁的严重威胁。升高的温度直接或间接改变了珊瑚-病原体相互作用的分布，从而加剧了传染性珊瑚病。病原性细菌弧菌弧菌是引起珊瑚感染的病原体。海平面上升的温度促进了这种细菌对珊瑚的感染，这引起了几种珊瑚病，例如细菌漂白，组织溶解和白色综合症。但是，人们对热应激对珊瑚对病原体免疫反应的影响了解甚少。为了描述热应激对珊瑚免疫力的影响，我们对造礁珊瑚的单生共生息肉进行了转录组分析。鹿角digitifera暴露于V. coralliilyticus热应力的条件下。热应激下的珊瑚溶血弧菌感染珊瑚对各种分子过程均具有负面影响，包括抑制与先天免疫反应有关的基因表达。响应病原体，珊瑚发出了各种反应，包括蛋白质代谢变化，释放外来体释放信号分子，细胞外基质重塑和线粒体代谢变化。基于这些结果，我们提供了新的见解，即在热应激条件下，指望草对病原体感染的固有免疫力。