题目: Genomic basis of evolutionary adaptation in a warm-blooded fish

作者: Xin Wang, Meng Qu, Yali Liu, Ralf F. Schneider, Yue Song, Zelin Chen, Hao Zhang, Yanhong Zhang, Haiyan Yu, Suyu Zhang, Dongxu Li, Geng Qin, Shaobo Ma, Jia Zhong, Jianping Yin, Shuaishuai Liu, Guangyi Fan, Axel Meyer, Dazhi Wang, Qiang Lin

刊物: The Innovation

年卷期页: 2021

摘要：Few fishes have evolved elevated body temperatures compared to ambient temperatures and only in opah (Lampris spp) is the entire body affected. To understand the molecular basis of endothermy, we analyzed the opah genome and identified 23 genes with convergent amino acid substitutions across fish, birds, and mammals, including slc8b1, which encodes the mitochondrial Na+ /Ca2+ exchanger and is essential for heart function and metabolic heat production. Among endothermic fishes, 44 convergent genes with suggestive metabolic functions were identified, such as glrx3, encoding a crucial protein for hemoglobin maturation. Numerous genes involved in the production and retention of metabolic heat were also found to be under positive selection. Analyses of opah’s unique inner heat-producing pectoral muscle layer, an evolutionary key-innovation, revealed that many proteins were co-opted from dorsal swimming muscles for thermogenesis and oxidative phosphorylation. Thus, the opah genome provides valuable resources and opportunities to uncover the genetic basis of thermal adaptations in fish.