Adaptive Evolution Patterns in the Pacific Oyster Crassostrea gigas
Adaptive Evolution Patterns in the Pacific Oyster Crassostrea gigas
复制标题
太平洋牡蛎的适应性进化模式
DOI：
10.1007/s10126-019-09906-w
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发表时间：
2019
影响因子：
3
通讯作者：
Zhang Guofan
中科院分区：
文献类型：
--
作者：
Song Kai;Wen Shiyong;Zhang Guofan
在分子水平上估计适应性进化速率在进化基因组学中很重要。然而，关于软体动物适应性进化模式的知识非常稀少，尤其是牡蛎。这些信息将有助于澄清牡蛎如何适应病原体丰富和动态变化的潮间带环境。在这项研究中，我们利用种群多样性分析和同源比较，表征了太平洋牡蛎基因组的适应性进化模式。我们的分析表明，基因表达模式与适应性进化速率呈正相关，这表明正选择在基因进化中发挥着重要作用。具有较多外显子和选择性剪接事件的基因具有较高的适应性进化率。免疫相关基因和应激反应基因的适应性进化率高于其他基因，表明这些基因经历了较强的正向选择。这项研究是第一次分析牡蛎的适应进化率，也是第一次对软体动物物种进行全面研究。这些结果为适应性进化速率与某些内在遗传因素之间的关联提供了系统水平的研究。他们还表明，对病原体和环境应激源的适应是推动基因适应性进化的重要力量。
Estimation of adaptive evolution rates at the molecular level is important in evolutionary genomics. However, knowledge of adaptive evolutionary patterns in Mollusca is very scarce, especially for oysters. Such information would help clarify how oysters adapt to pathogen-rich and dynamically changing intertidal environments. In this study, we characterized the patterns of adaptive evolution in the Crassostrea gigas genome, using population diversity analysis and congeneric comparison. Our analysis revealed that gene expression patterns were positively associated with adaptive evolution rates, which suggested that positive selection played an important role in gene evolution. The genes with more exons and alternative splicing events had higher adaptive evolution rates. The rates of adaptive evolution in immune-related and stress-response genes were higher than those in other genes, suggesting that these groups of genes experienced strong positive selection. This study represents the first analysis of adaptive evolution rates in oysters and the first comprehensive study of a Mollusca species. These results provide a system-level investigation of association between adaptive evolution rates with some intrinsic genetic factors. They also suggest that adaptation to pathogens and environmental stressors are important forces driving the adaptive evolution of genes.