Institute of Deep-Sea Science and Engineering, Chinese Academy of Sciences, Sanya, China.
University of Chinese Academy of Sciences, Beijing, China.
Mol Biol Evol. 2021 May 19;38(6):2413-2427. doi: 10.1093/molbev/msab035.
Endothermy is a typical convergent phenomenon which has evolved independently at least eight times in vertebrates, and is of significant advantage to organisms in extending their niches. However, how vertebrates other than mammals or birds, especially teleosts, achieve endothermy has not previously been fully understood. In this study, we sequenced the genomes of two billfishes (swordfish and sailfish), members of a representative lineage of endothermic teleosts. Convergent amino acid replacements were observed in proteins related to heat production and the visual system in two endothermic teleost lineages, billfishes and tunas. The billfish-specific genetic innovations were found to be associated with heat exchange, thermoregulation, and the specialized morphology, including elongated bill, enlarged dorsal fin in sailfish and loss of the pelvic fin in swordfish.
温血是一种典型的趋同现象，在脊椎动物中至少独立进化了八次，这对生物扩大其生态位具有重要意义。然而，除了哺乳动物或鸟类之外的脊椎动物，特别是硬骨鱼，是如何实现温血的，以前并没有得到充分的了解。在这项研究中，我们对两种旗鱼（剑鱼和马林鱼）的基因组进行了测序，它们是温血硬骨鱼的一个代表性谱系的成员。在两个温血硬骨鱼谱系——旗鱼和金枪鱼中，与产热和视觉系统相关的蛋白质观察到了趋同的氨基酸替换。旗鱼特有的遗传创新与热交换、体温调节以及特殊的形态有关，包括狭长的喙、马林鱼中增大的背鳍和剑鱼中失去的臀鳍。
