Cheng Luman, Xu Xiuming, Wang Minghua, Wang Da-Zhi
State Key Laboratory of Marine Environmental Science/College of the Environment and Ecology, Xiamen University, Xiamen, China.
Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems/College of the Environment and Ecology, Xiamen University, Xiamen, China.
Glob Chang Biol. 2024 Dec;30(12):e17602. doi: 10.1111/gcb.17602.
Studies have demonstrated that marine phytoplankton can adapt to the warmer environment. However, the underlying mechanisms remain largely unknown. Here, we quantified the capacity of a globally distributed marine diatom Skeletonema dohrnii, for rapid evolution under the moderate (24°C) and severe (28°C) warming scenarios. Whole-genome resequencing analysis revealed that the evolutionary adaptation of S. dohrnii to moderate warming was slow (i.e., 700 generations), whereas it was rapid (i.e., 300 generations) under severe warming but suffered a substantial loss of genetic diversity within the population. Genes associated with energy production and lipid metabolism evolved rapidly, particularly under severe warming, suggesting their vital roles in thermal adaptation. Proteomic results also showed the enhanced expression of proteins involved in energy production and lipid metabolism, especially under severe warming. Furthermore, particulate organic carbon and nitrogen production was greatly enhanced in the moderate warming-selected population but increased insignificantly in the severe warming-selected population, indicating more rapid adaptation driven by severe warming. Our results provide molecular insights into the rapid but limited evolution of thermal adaptation in marine diatoms and highlight energy production and lipid metabolism as the most important adaptive strategy. Future warming will affect genetic diversity and population dynamics of diatoms in the ocean.
研究表明，海洋浮游植物能够适应更温暖的环境。然而，其潜在机制在很大程度上仍不为人知。在此，我们量化了全球分布的海洋硅藻多纹骨条藻（Skeletonema dohrnii）在适度（24°C）和严重（28°C）变暖情景下快速进化的能力。全基因组重测序分析表明，多纹骨条藻对适度变暖的进化适应较为缓慢（即700代），而在严重变暖情况下则较为迅速（即300代），但种群内遗传多样性大幅丧失。与能量产生和脂质代谢相关的基因进化迅速，尤其是在严重变暖情况下，这表明它们在热适应中起着至关重要的作用。蛋白质组学结果还显示，参与能量产生和脂质代谢的蛋白质表达增强，特别是在严重变暖情况下。此外，适度变暖选择的种群中颗粒有机碳和氮的产生大幅增加，而严重变暖选择的种群中增加不显著，这表明严重变暖驱动了更快的适应。我们的研究结果为海洋硅藻热适应的快速但有限的进化提供了分子见解，并强调能量产生和脂质代谢是最重要的适应策略。未来的变暖将影响海洋中硅藻的遗传多样性和种群动态。
