基于16S rRNA基因分析虫草寄主蝠蛾的系统进化关系

Phylogenetic Relationships of Host Insects of Ophiocordyceps Sinensis Based on 16S rRNA Gene

为了解虫草寄主昆虫的系统进化关系,基于线粒体DNA(mtDNA)16S rRNA基因对7种虫草寄主蝠蛾、2种其他蝠蛾及其他科蛾类的系统进化关系进行研究.用ClustalX 2.1软件对11种蝠蛾16S rRNA基因进行序列对位排列,DAMBE软件分析基因序列的碱基组成及AT或GC偏斜性.用MEGA 7.0统计不同基因序列间的位点数目以及蝠蛾科蝠蛾种间遗传间距,并以果蝇(Drosophila yakuba)做外群,构建分子系统进化树.结果表明:11种蝠蛾的16S rRNA基因序列进行比对排列后,共1411 bp,其A+T的平均含量为85.3%,保守位点1054个,简约位点143个,可变位点310个.11种蝠蛾种间遗传距离为0.005~0.117,其中人支蝠蛾与阿尔泰蝠蛾和贡嘎蝠蛾的种间遗传距离均为0.005,Triodia sylvina与蒲氏钩蝠蛾遗传距离最大(0.117).分别以16S rRNA和16S rRNA联合COⅠ基因构建分子系统树,分析表明蝠蛾科虫草寄主蝠蛾间的关系较近,而与其他蛾类关系较远,其亲缘关系远近与其地理分布有一定关系,与形态学分类观点相吻合.以上结果说明,16S rRNA基因是适用于虫草寄主蝠蛾分类研究的一种有效标记基因.

In order to understand the phylogeny of host insects of the fungus Ophiocordyceps sinensis,this paper investigate the phylogenetic relationship of the mitochondrial DNA(mtDNA)16 S rRNA gene to 11 species of Hepialildae and other family.The 16 S rRNA genes of 11 species of Hepialildae were aligned by ClustalX(2.1)software,and the base composition and AT or GC skew of the gene sequence wereanalyzed using DAMBE software.We counted the number of sites between different gene sequences and the genetic distance between the species of Hepialildae and constructed a molecular phylogenetic tree using MEGA 7.0.The results showed that the 16 S rRNA gene sequences of 11 species of Hepialildae was 1411 bp in length with an average A+T content of 85.3%,1054 conserved site,143 parsimony infoanative site,and 310 variable site.The genetic distance between 11 species of Hepialildae was 0.005~0.117.The genetic distance between the Thitarodes renzhiensis and Thitarodes sp.and Thitarodes gonggaensis was 0.005,and the genetic distance between Triodia sylvina and Thitarodes pui was the largest(0.117).Molecular phylogenetic tree showed that the relationship among host insects of the fungus O.sinensis was closer than that of other moths.The genetic relationship is related to the geographical environment of the distribution area.The above results indicate that the 16 S rRNA gene is an effective marker gene for classification studies.