有齿食道口线虫ITS及5.8S DNA片段的PCR扩增、克隆及序列分析

 运用PCR方法以保守引物NC5及NC2扩增了从广东阳江地区猪体分离的食道口线虫rDNA 的内转录间隔区（ITS）及5.8S序列。将PCR扩增出的片段纯化后克隆至pGEM-T Easy载体，用PCR技术及酶切鉴定阳性菌落，对阳性菌落质粒DNA进行测序。结果表明，扩增的片段大小为828 bp，包含部分的18S、28S及全部的ITS-1（362 bp）、5.8S(153 bp)及ITS-2（217 bp）序列。序列比较表明，该食道口线虫为有齿食道口线虫。本研究在国际上首次报道了中国猪有齿食道口线虫的ITS及5.8S序列，为食道口线虫的分子生物学的进一步研究奠定了基础。

PCR Amplification, Cloning and Sequence Analysis of the ITS and 5.8S rDNA of Oesophagostomum Isolates

The internal transcribed spacer (ITS) and 5.8S rDNA of Oesophagostomum spp isolated from Guangdong Province was amplified by PCR using a pair of conserved primers and the amplicons were cloned into pGEM-T Easy vector. The inserts were successfully sequenced, and the results revealed that the inserts were 828 bp in length and consisted of partial 18S, 28S, and complete ITS-1, 5.8S and ITS-2 DNA sequences. The Oesophagostomum isolates were identified as O.dentatum based on ITS-2 sequence. It was the first time that the complete sequence of ITS-1 and 5.8S rDNA of Oesophagostomum dentatum was reported. The results of the present study have laid a foundation for further studies of Oesophagostomum.