Summary Marine microalgae demonstrate a notable capacity to adapt to high CO2 and warming in the context of global change. However, the dynamics of their evolutionary processes under simultaneous high CO₂ and warming conditions remain poorly understood. Here, we analyze the dynamics of evolution in experimental populations of a model marine diatom Phaeodactylum tricornutum. We conducted whole‐genome resequencing of populations under ambient, high‐CO2, warming and high CO2 + warming at 2‐yr intervals over a 4‐yr adaptation period. The common genes selected between 2‐ and 4‐yr adaptation were found to be involved in protein ubiquitination and degradation and the tricarboxylic acid (TCA) cycle, and were consistently selected regardless of the experimental conditions or adaptation duration. The unique genes selected only by 4‐yr adaptation function in respiration, fatty acid, and amino acid metabolism, facilitating adaptation to prolonged high CO2 with warming conditions. Corresponding changes at the metabolomic level, with significant alterations in metabolites abundances involved in these pathways, support the genomic findings. Our study, integrating genomic and metabolomic data, demonstrates that long‐term adaptation of microalgae to high CO2 and/or warming can be characterized by a complex and dynamic genetic process and may advance our understanding of microalgae adaptation to global change.

中文翻译：

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高 CO2 海洋中微藻的适应性进化动力学


摘要 海洋微藻在全球变化的背景下表现出适应高 CO2 和变暖的显着能力。然而，在同时高 CO₂ 和变暖条件下，它们的进化过程动力学仍然知之甚少。在这里，我们分析了模式海洋硅藻 Phaeodactylum tricornutum 的实验种群的进化动力学。我们在 4 年的适应期内以 2 年的间隔对环境、高 CO2、变暖和高 CO2 + 变暖下的种群进行了全基因组重测序。发现在 2 年和 4 年适应之间选择的共同基因参与蛋白质泛素化和降解以及三羧酸 （TCA） 循环，并且无论实验条件或适应持续时间如何，都被一致选择。仅通过 4 年适应选择的独特基因在呼吸、脂肪酸和氨基酸代谢中发挥作用，有助于适应变暖条件下的长期高 CO2。代谢组学水平的相应变化，以及这些途径中涉及的代谢物丰度的显著变化，都支持基因组学发现。我们的研究整合了基因组和代谢组学数据，表明微藻对高 CO2 和/或变暖的长期适应可以以复杂和动态的遗传过程为特征，并可能促进我们对微藻适应全球变化的理解。