分子进化与基因组多样性（张亚平）知识库

以亲缘关系极近的近缘种类群、中等距离的远缘种类群为对象，分析生物钟基因period基因的Thr-Gly区段的分子进化特征，发现Thr-Gly区段在果蝇和部分双翅目昆虫中未曾经历性选择和其他定向的正选择。Thr-Gly区段在果蝇nasuta亚群中的分子进化速率为10.4*10~-9同义替换/位点/年。

In this study, the molecular evolution of the Thr-Gly region of the period gene was characterized, using dipteran groups with close, medium, and long distance phylogenetic relationship. No sexual selection or other positive selection was found to be acting on the Thr-Gly region. The evolutionary rate of the Thr-Gly region in nasuta subgroup was 10.4 x 10(-9) synonymous substitution/site/year. The divergence time of the nasuta subgroup of Drosophila was estimated to be 1-3 mya. A phylogenetic tree of Drosophila genus was reconstructed, which is well supported by evidences from archaebiological and biogeographical studies, The molecular evolutionary pattern of Thr-Gly region was discussed.