分子进化与基因组多样性（张亚平）知识库

In this study, we identified two novel members of prolactin gene family in rat by blast searches against the published genomic database. A further analysis showed that gene duplications leading to PRL gene family in rodents occurred after rodents diverged from other mammals. Major reorganization of the gene loci in rodents was largely completed before the split of rat and mouse. But PL-Ⅰ and PL-Ⅱ genes are the exceptions, which have clustered in a species-specific manner in the phylogenetic tree. By combining results from gene conversion testing, relative chromosomal location comparison and estimated time for gene duplication we believe that rodent PL-Ⅰ and PL-Ⅱ genes are species-specific and are the results of serial duplications which occurred after the divergence of mouse and rat. Our analysis also reveals that continual gene duplication and divergence occurred during the evolution of rodent PRL gene family.

在大鼠基因组数据库中搜索得到两个泌乳刺激素基因家族的新成员。进一步分析显示该基因家族起源于啮齿目和其他哺乳动物分歧之后，而且大部分基因座位的重排在大、小鼠分歧之前已经完成。但PL-Ⅰ和PL-Ⅱ基因簇却是例外，它们在基因树上以物种特异的方式聚类。结合基因转换的检验、染色体上相对位置比较和基因重复时间估计的结果，认为啮齿目PL-Ⅰ和PL-Ⅱ基因是物种特异的，它们由一系列在大、小鼠分歧之后发生的基因重复事件形成。结果还揭示了在啮齿目泌乳刺激素基因家族进化过程中持续不断的发生了基因重复和基因分化事件。