Data from: Variation in the transcriptional response of threatened coral larvae to elevated temperatures

Coral populations have declined worldwide largely due to increased sea surface temperatures. Recovery of coral populations depends in part upon larval recruitment. Many corals reproduce during the warmest time of year when further increases in temperature can lead to low fertilization rates of eggs and high larval mortality. Microarray experiments were designed to capture and assess variability in the thermal stress responses of Acropora palmata larvae from Puerto Rico. Transcription profiles showed a striking acceleration of normal developmental gene expression patterns with increased temperature. The transcriptional response to heat suggested rapid depletion of larval energy stores via peroxisomal lipid oxidation and included key enzymes that indicated the activation of the glyoxylate cycle. High temperature also resulted in expression differences in key developmental signalling genes including the conserved WNT pathway that is critical for pattern formation and tissue differentiation in developing embryos. Expression of these and other important developmental and thermal stress genes such as ferritin, heat shock proteins, cytoskeletal components, cell adhesion and autophagy proteins also varied among larvae derived from different parent colonies. Disruption of normal developmental and metabolic processes will have negative impacts on larval survival and dispersal as temperatures rise. However, it appears that variation in larval response to high temperature remains despite the dramatic population declines. Further research is needed to determine whether this variation is heritable or attributable to maternal effects.全球珊瑚种群（coral populations）的数量已大幅下降，主要归因于海表温度（sea surface temperatures）的持续升高。珊瑚种群的恢复在一定程度上依赖于幼体补充（larval recruitment）。多数珊瑚于一年中温度最高的时段进行繁殖，此时若温度进一步升高，会导致卵子受精率降低以及幼体死亡率升高。本研究设计了微阵列实验（microarray experiments），以捕获并评估来自波多黎各的棕榈鹿角珊瑚（Acropora palmata）幼体的热胁迫响应变异。转录谱（transcription profiles）分析显示，随着温度升高，幼体的正常发育基因表达模式出现显著加速。对热刺激的转录响应表明，幼体能量储备通过过氧化物酶体脂质氧化（peroxisomal lipid oxidation）被快速消耗，且该过程包含了激活乙醛酸循环（glyoxylate cycle）的关键酶类。高温还会导致关键发育信号通路基因的表达出现差异，其中包括在胚胎发育过程中对模式形成与组织分化至关重要的保守WNT信号通路（WNT pathway）。这类基因以及铁蛋白（ferritin）、热休克蛋白（heat shock proteins）、细胞骨架组分（cytoskeletal components）、细胞黏附分子与自噬蛋白（autophagy proteins）等其他重要的发育相关与热胁迫相关基因的表达，在不同亲本珊瑚群体（parent colonies）来源的幼体之间同样存在差异。随着全球温度持续升高，正常发育与代谢过程的紊乱会对珊瑚幼体的存活与扩散产生负面影响。不过尽管珊瑚种群已出现大幅衰退，其幼体对高温的响应仍存在个体差异。未来仍需开展进一步研究，以明确这种差异是可遗传的，还是由母体效应（maternal effects）所导致。