蛇蛔虫ITS及5.8S rDNA的克隆及进化分析

Cloning and phylogenetic analysis of the ITS and 5.8S rDNA of ascarid nematodes from Zaocys dhumnades

利用聚合酶链反应(PCR)扩增蛇蛔虫rDNA的ITS-1、5.8S及ITS-2片段,将PCR扩增出的片段纯化后克隆至pGEM-T Easy载体,重组质粒通过菌落PCR鉴定后,对阳性菌落进行序列测定并进行序列分析。结果显示,所获得的蛇蛔虫ITS及5.8SrDNA序列总长为846bp,包含部分的18S、28S及全部的ITS-1、5.8S及ITS-2序列。本研究系国际上首次报道蛇蛔虫的ITS序列,从而为蛇蛔虫的分类鉴定以及进一步的分子流行病学调查奠定了基础。

The ITS sequences were amplified from each ascarid sample and the amplicons were cloned into pGEM-T Easy vector,respectively.The inserts were successfully sequenced,and the length of ITS in all samples were 846 bp.Sequence analysis revealed that the isolates contained the seguence of complete ITS-1,5.8 S and ITS-2 rDNA.It was the first time report of the complete sequence of ITS and 5.8S rDNA of ascarid nematodes from Zaocys dhumnades.The results of this study lay down the foundation for further study on molecular epidemiology and diagnostics of ascarid nematodes from snakes.