4.3 Adaptive mechanism of metabolism related genes
Through the analysis of GO terms enriched by positive selection genes, we found that positive selection genes were mainly significantly enriched in GO terms related to metabolism, and involved in various metabolic processes, for example: oxidation-reduction process, lipid metabolism process, catabolic process, and biosynthesis process. The abundance of these metabolism-related positive selection genes in specieslow indicates that these species have the stronger positive selection in energy metabolism or biosynthesis than other species.
Adaptation of energy metabolism plays a very important role in the evolutionary process of species. Bats can fly, which requires huge energy consumption (Shen et al., 2010), so genes related to energy metabolism play an important role in the evolutionary process of bats. Due to the high efficiency of aerobic respiration, which plays a major role in the energy supply process, specieslow can obtain more energy by improving mitochondria and oxidation-reduction pathways. Some positive selection genes and positive selection sites were detected in mitochondria (Zhang et al., 2021), the main energy supply organelles, which is consistent with the results of positive selection detected in genes related to energy metabolism in this study. These results suggested that energy-related genes have undergone adaptive evolution in specieslow, and these species have a stronger selective role in energy metabolism and may improve some aspects of adaptability by regulating energy metabolism in the process of evolution.
Although GO terms enriched by positive selection genes are mostly related to metabolism, there are differences in GO terms enriched among different species, indicating that these species may experience different evolutionary processes, and corresponding genes may play potentially important roles in the evolutionary process of different species.