The Key Laboratory of Mariculture, Ministry of Education, Fisheries College, Ocean University of China, Qingdao, 266003, PR China.
College of Life Science, Yantai University, Yantai, 264005, China.
Commun Biol. 2023 Jan 3;6(1):5. doi: 10.1038/s42003-022-04407-4.
The roles of synonymous mutations for adapting to stressful thermal environments are of fundamental biological and ecological interests but poorly understood. To study whether synonymous mutations influence thermal adaptation at specific microhabitats, a genome-wide genotype-phenotype association analysis is carried out in the black mussels Mytilisepta virgata. A synonymous mutation of Ubiquitin-specific Peptidase 15 (MvUSP15) is significantly associated with the physiological upper thermal limit. The individuals carrying GG genotype (the G-type) at the mutant locus possess significantly lower heat tolerance compared to the individuals carrying GA and AA genotypes (the A-type). When heated to sublethal temperature, the G-type exhibit higher inter-individual variations in MvUSP15 expression, especially for the mussels on the sun-exposed microhabitats. Taken together, a synonymous mutation in MvUSP15 can affect the gene expression profile and interact with microhabitat heterogeneity to influence thermal resistance. This integrative study sheds light on the ecological importance of adaptive synonymous mutations as an underappreciated genetic buffer against heat stress and emphasizes the importance of integrative studies at a microhabitat scale for evaluating and predicting the impacts of climate change.
同义突变在适应应激热环境中的作用具有重要的生物学和生态学意义，但人们对此知之甚少。为了研究同义突变是否会影响特定小生境中的热适应，我们对贻贝 Mytilisepta virgata 进行了全基因组基因型-表型关联分析。泛素特异性肽酶 15（MvUSP15）的同义突变与生理上限热显著相关。与携带 GA 和 AA 基因型（A 型）的个体相比，携带突变位点 GG 基因型（G 型）的个体耐热性显著降低。当加热至亚致死温度时，G 型个体的 MvUSP15 表达个体间差异更大，特别是在阳光直射的小生境中的贻贝。总之，MvUSP15 中的同义突变可以影响基因表达谱，并与小生境异质性相互作用，影响热抗性。这项综合研究揭示了适应性同义突变作为一种被低估的遗传缓冲对热应激的生态重要性，并强调了在小生境尺度上进行综合研究以评估和预测气候变化影响的重要性。
