犬瘟热病毒N基因和M基因的克隆与序列分析

The Cloning and Sequence Analysis of N Gene and M Gene of Canine Distemper Virus

以从宠物临床上分离的犬瘟热病毒(canine distemper virus,CDV)总RNA为模板,根据GenBank中已报道的CDV核蛋白(N)、基质膜蛋白(M)基因序列,分别设计合成1对特异性引物,RT-PCR扩增N、M蛋白编码基因,并进行克隆与序列分析。结果显示,均扩增出预期大小的片段。扩增片段经核苷酸序列分析,N、M编码基因全长分别为1572、1008 bp,该CDV的N蛋白编码基因序列与Onderstepoort疫苗株、A75/17株的同源性分别为93.9%、97.6%,编码氨基酸的同源性分别为96.9%、98.7%;M蛋白编码基因序列与Onderstepoort疫苗株、A75/17株的同源性分别为94.5%、97.8%,编码氨基酸的同源性分别为97.9%、99.7%,这说明N、M蛋白均是保守性较强的结构蛋白,且同强毒株A75/17的亲缘关系要比Onder-stepoort疫苗株更近。

According to the reported gene sequence of N protein and M protein of canine distemper virus（CDV） in GenBank,two special pair of primers were designed to RT-PCR amplify N protein coding gene and M protein coding gene by using the total RNA isolated CDV from pet clinic as templates,then the two products were cloned and sequenced.The results showed that the expected length fragments were amplified.The sequence analysis of the amplified fragments showed that the length of N gene was 1572 bp and that of M gene was 1008 bp.The homology of N protein gene sequence between this strain and Onderstepoort strain was 93.9% and A75/17 stain（97.6%）,and the homology of coding amino acid between CDV SH strain and Onderstepoort strain was 96.9% and A75/17（98.7%）.The homology of M protein gene sequence between this strain and Onderstepoort strain was 94.5% and A75/17 stain（97.8%）,and the homology of coding amino acid between CDV SH strain and Onderstepoort strain was 97.9% and A75/17（99.7%）.It can be predicted that N protein and M protein have highly conservative property and more close genetic relationship with A75/17 strain than that of Onderstepoort strain.