湖南省猬迭宫绦虫的线粒体nad5和rrnS基因的序列测定及种系发育分析

Sequence and phylogenetic analysis of mitochondrial nad5 and rrnS genes for Spirometra erinaceieuropaei isolates from Hunan province

本研究旨在阐明猬迭宫绦虫湖南分离株线粒体烟酰胺腺嘌呤二核苷酸(NADH)脱氢酶亚单位5基因(nad5)部分序列(pnad5)和核糖体小亚基基因(rrnS)部分序列(prrnS)的遗传变异情况,并用pnad5和prrnS序列重构猬迭宫绦虫与其他绦虫的种群遗传关系。利用聚合酶链反应(PCR)扩增猬迭宫绦虫的pnad5和prrnS,应用ClustalX 1.81程序对序列进行比对,再用Phylip3.67程序MP法和Mega4.0程序NJ法绘制种系发育树,并用Puzzle5.2程序构建最大似然树。结果显示,所获得的pnad5和prrnS序列与预期(片段的)长度一致,分别为531bp和328bp。种系发育树表明,湖南分离株与已知猬迭宫绦虫位于同一分枝。结果表明,由于猬迭宫绦虫pnad5和prrnS序列种内相对保守,种间差异较大,均可作为种间遗传变异研究的标记。

The objectives of the present study were to examine sequence variation in the mitochondrial NADHdehydrogenase subunit 5（nad5） gene and small subunit of ribosomal RNA（rrnS） gene among Spirometra erinaceieuropaei isolates from Hunan province,and to reconstruct their phylogenetic relationship using nad5 and rrnS sequences.The partial nad5（pnad5） and rrnS（prrnS） were amplified from each S.erinaceieuropaei sample,and pnad5 and prrnS sequences were aligned using the Clustal X 1.81.MP and NJ trees of pnad5 and prrnS were constructed using the software Phylip 3.67 version 4.0 and Mega version 4.0,and ML tree was also constructed using Puzzle version 5.2.The results showed that the lengths of pnad5 and prrnS sequences were 531 bp and 328 bp,respectively.The constructed phylogenetic tree revealed that the Hunan isolates and the S.erinaceieuropaei available in GenBank were clustered in the same clade.There is no significant variation in pnad5 and prrnS sequences within S.erinaceieuropaei,while inter-species difference is obvious.It is concluded that pnad5 and prrnS sequences can be used as genetic marker for population genetic studies of cestodes.