装饰短蚋线粒体全基因组序列测定与分析

Sequencing and analysis of the complete mitochondrial genome sequence of Simulium Ornatum

目的测定和注释装饰短蚋(Simulium ornatum)线粒体全基因组序列,并在线粒体基因组水平上分析短蚋亚属与蚋亚属、纺蚋亚属之间的系统发育关系。方法采用长PCR扩增加引物步移法和总DNA测序法对装饰短蚋线粒体全基因组序列进行扩增测序,应用邻接法重建装饰短蚋与其近缘物种的系统发育关系。结果装饰短蚋线粒体基因组序列全长为15640 bp,包括13个蛋白质编码基因(PCGs)、2个rRNA基因、22个tRNA基因及1个控制区(CR),A、T、C、G碱基含量分别为38.1%、36.4%、14.7%、10.8%;基于13个PCGs序列构建的系统发育关系表示为{[(S.ornatum+S.variegatum)+S.maculatum]+S.aureohirtum}+S.quinquestriatum,基于DNA条码序列构建系统发育关系表示为{[(S.ornatum+S.variegatum)+S.quinquestriatum]+S.maculatum}+S.aureohirtum。结论短蚋亚属与蚋亚属杂色蚋组(variegatum group)的亲缘关系最近,利用线粒体全基因组进行系统发育分析DNA条码序列具有更高的分辨率。

Objective To sequence and interpret the complete mitochondrial(mt)genome sequence of Simulium ornatum,and to analyze the phylogenetic relationships of subgenus Odagmia,subgenus Simulium,subgenus Byssodon,and subgenus Nevermannia on the mt genome level.Methods The mt-genome sequences of S.ornatum were amplified and sequenced by long PCR amplification plus primer walking and total DNA sequencing method,and the phylogenetic relationships between S.ornatum and its close species were reconstructed by neighbor-joining method.Results The length of the complete mt-genomes of S.ornatum was 15640 bp,including 13 protein-coding genes(PCGs),2 rRNA genes,22 tRNA genes,and 1 control region(CR).The base contents of S.ornatum were 38.1%of A,36.4%of T,14.7%of C and 10.8%of G.The phylogenetic tree based on 13 PCGs was displayed as{[(S.ornatum+S.variegatum)+S.maculatum]+S.aureohirtum}+S.quinquestriatum;based on DNA barcodes,{[(S.ornatum+S.variegatum)+S.quinquestriatum]+S.maculatum}+S.aureohirtum.Conclution The subgenus Odagmia is most closely related to the variegatum group of the subgenus Simulium;the whole mt-genomes have higher resolution than DNA barcodes for phylogenetic analysis.