蓖麻蚕线粒体cox2基因的克隆、序列测定和分子系统学分析  

Molecular Characterization of the Cytochrome Oxidase Subunit Ⅱ Gene of Mitochondrial DNA From the Eri Silkworm Samia cynthia ricini

作　　者：陈复生[1] 魏兆军[2] 李庆宝[3] 鲍先巡[1] 汪泰初[1] 

机构地区：[1]安徽省农业科学院蚕业研究所,合肥230061 [2]中国科技大学生命科学院 [3]安徽省农业委员会蚕桑服务站

出　　处：《蚕业科学》2004年第1期38-43,共6页ACTA SERICOLOGICA SINICA

基　　金：安徽省重点科研项目 (编号 0 10 41172 )

摘　　要：利用兼并性引物克隆出蓖麻蚕线粒体cox2基因、tRNA Leu基因和cox1基因的部分片段。cox2基因编码框包含 6 85个核苷酸 ,编码 2 2 8个氨基酸的蛋白质 ;起始密码子为ATG ,终止密码子仅有 1个T组成 ;蓖麻蚕mtDNA的cox2基因中富含AT ,含量为 75 77% ,GC的含量为 2 4 2 3%。通过同源性比较 ,发现蓖麻蚕的cox2与柞蚕cox2同源性最高 ,核苷酸和氨基酸序列同源性分别是 89 0 %和 96 0 %。根据cox2氨基酸序列进行了 12种昆虫的分子系统学分析探讨。cox2 gene, tRNA-Gly gene and partical cox1 gene of mitochondrial DNA of Samia cynthia ricini were cloned and sequenced. The open reading frame of cox2 gene contains 685 nucleotides, encoding a putative protein of 228 amino acids. The percent of A and T 75.77%, is more than that of G and C 24.23%. The initial codon of mt cox2 of Samia cynthia ricini is ATG. The cox2 mt gene use an incomplete termination codon. Comparison of the amino acid homology with other cox2 of mtDNA was made. The results showed that the conservation of C′ termination was higher than N′ termination of cox2, there were two conservative regions in C′ termination of cox2, that the cox2 gene of mtDNA in Eri silkworm was most closely related to that of Antheraea pernyi, with the homology of 89.0% nucleotide and 96.0% amino acid respectively. Based on the alignment of amino acid sequences, a phylogenetic tree of 12 insect cox2 genes was constructed.

关 键 词：蓖麻蚕 线粒体 cox2基因 克隆 序列测定 聚类分析 

分 类 号：S885.2[农业科学—特种经济动物饲养]