双壳贝类线粒体基因组结构的比较

摘要

利用比较基因组学和生物信息学方法,比较分析了已登录到GenBank中的14种海产双壳贝类和2种淡水双壳贝类的线粒体基因组的结构特征.结果发现,双壳贝类线粒体的基因组结构、基因排列顺序均互不相同;不同目、科和属之间线粒体基因组的大小、基因排列方式以及基因种类也存在明显的差异,尤其是基因排列方式没有明显的规律.对16种双壳贝类的线粒体基因组全序列、编码基因序列进行系统分析,分别得到了不同的聚类结果,即用基因组全序列聚类时,16种贝类的聚类结果与传统的形态学分类地位基本相同;而将16种贝类的所有蛋白质编码基因和2个rRNA基因按照一致顺序排列起来进行聚类时,所得的系统分类情况与这些贝类传统的形态学分类地位相差较大.%The structure and organization of mitochondrial genomes of 14 marine bivalves and two freshwater bivalves were analyzed using comparative genomics and bioinformatics methods. The results showed that the organization and gene order of the mitochondrial genomes of these bivalve species studied were different from each other. The size, organization, gene numbers, and gene order of mitochondrial genomes in bivalves at different taxa were different. Phylogenetic analysis using the whole mitochondrial genomes and all the coding genes showed different results--phylogenetic analysis conducted using the whole mitochondrial genomes was consistent with the existing classification and phylogenetic analysis conducted using all coding genes not consistent with the existing classification.