细粒棘球蚴线粒体nad1基因的克隆与序列分析

目的为完善细粒棘球蚴(Echinococcus granulasus)的分子分类学体系,提供更优化的种间和种内遗传标记基因。方法在内蒙古地区采集患羊肝脏细粒棘球蚴和肝包虫病患者棘球蚴。采用提取虫体DNA的方法,扩增线粒体NADH脱氢酶1(nad 1)基因并进行测序,运用DNAstar5.0软件构建系统发育树并采用MEGA4.0软件进行自居检验。结果细粒棘球蚴DNA扩增出的羊株、人株nad 1基因序列片段长度为895 bp。羊株、人株细粒棘球蚴nad1序列与加拿大棘球绦虫的同源性最高,相似性为86.5%;羊株、人株细粒棘球蚴nad1序列与加拿大棘球绦虫位于同一分支,自展值(Boostrap)最高,为100%。羊株、人株细粒棘球蚴nad1序列所属分支与裂头目、裂头科Diplogonoporus balaenopterae所属分支相隔最远。结论nad 1基因有较高保守性,同时也存在种间差异,可广泛应用于研究细粒棘球绦虫的种间和种内遗传变异。

Cloning and sequence analysis of the partial nad1 gene within mitochondrial DNA of Echinococcus granulosus

To further improve the molecular taxonomy of Echinococcus granulosus and provide more optimized inter and intraspecific marker genes.The mitochondrial NADH dehydrogenase 1 (nad1) gene was amplified and sequenced from the DNA of the Echinococcus granulosus extracted from infected sheep and patients in Inner Mongolia, then the phylogenetic tree was constructed using DNAStar 5.0 and identified by MEGA 4.0 softwares. As the result, the sequence length of nad1 gene of sheep and human strain amplified from E. granulosus DNA was 895 bp, which was 86.5% similar to that of E. canadensis, located in the same branch, with the highest bootstrap value of 100%. However, the branch of nad 1 sequence in the sheep and human E. granulosus was the farthest from that of Diplogonoporus balaenopterae. In conclusion, the nad1 genes were highly conserved and had interspecific differences, which can be widely used to study the inter and intraspecific genetic variation of echinococcus granulosus.