广西不同时期IBV分离株S1基因高变区Ⅰ的遗传变异分析  

Genetic Variation of S1 Gene Hypervariable Region I of Infectious Bronchitis Viruses Isolated in Different Periods in Guangxi

作　　者：韦正吉[1] 韦平[1] 磨美兰[1] 李孟[1] 韦天超[1] 李康然[1] 

机构地区：[1]广西大学养禽与禽病研究所,广西南宁530005

出　　处：《病毒学报》2008年第2期126-132,共7页Chinese Journal of Virology

基　　金：国家自然科学基金(30700599);广西自然科学基金(桂科青0728003);广西区教育厅科研项目(C150002);广西大学科研项目(DD150032);硕士研究生科研创新项目(2007105930906M87)

摘　　要：对广西1985-2007年间分离到的22株传染性支气管炎病毒（IBV）的S1基因高变区I（HVRI）进行序列测定，并与发表的其他IBV参考株及鸽子分离的冠状病毒株的基因序列进行比较和分析。系统进化关系显示毒株可分为5个基因群，其中有16个广西分离株属第1群，它们与鸽子冠状病毒分离株的氨基酸序列同源性较高，与Massachusetts（Mass）型疫苗株的同源性较低。有15个分离株在33-34位和34～35之间分别有4个和3个氨基酸残基的插入，GX-NN6在33～34位和34～35位之间则均有4个氨基酸残基的插入；GX-YL1、GX-NN2与常用的Mass型疫苗株的亲缘关系最近，同属于第Ⅱ群；GX-G、GX-XD与日本同一时期分离的毒株JP Miyazaki 89亲缘关系最近，属于第Ⅲ群；GX-YL6、GX-NN7与欧洲毒株4／91亲缘关系较近，属于第V群。结果表明广西存在着多种类型IBV毒株的流行，毒株S1基因HVRI碱基的突变或插入比较普遍，可导致其氨基酸序列的变化，绝大部分毒株与目前常用的Mass型疫苗株的亲缘关系较低。同一时期的分离株同源性较高，但无明显的地域性差异。The S1 gene hypervariable region I （HVR I） of 22 infectious bronchitis virus （IBV） strains isolated in Guangxi during the period of 1985-2007 were sequenced and compared to that of the other IBV reference strains and the pigeon coronavirus isolates. A phylogenetic tree based on nucleotide sequences of HVR I of all the IBV showed that they were classified into 5 distinct Clusters. 16 out of 22 IBV isolates were grouped into Cluster I , and had higher homology with pigeon coronavirus isolates but lower homology with the Massachusetts（Mass）type vaccine strains. There were 4 and 3 amino-acid residues inserted at the sites of 33-34 and 34-35 respectively within HVR I in 15 isolates, except in isolate GX-NN6 there had 4 amino-acid residues inserted at the both sites; isolates GX-YL1 and GX-NN2 had close relationship with Mass type vaccine strains, and they shared Cluster Ⅱ ; isolates GX-G and GX-XD of Cluster m had close relationship with the Japanese strain JP Miyazaki 89 which was isolated at the same period; isolates GX- YL6 and GX-NN7 of Cluster V had close relationship with the European strain 4/91. The results showed that there were high phylogenetic diversity among the IBVs prevailed in the field in Guangxi resulting from the commonly occurred mutation or insertion within the S1 gene HVR I of the viruses, and majority of the isolates had lower homology with the commonly used Mass type vaccine strains. There was much higher homology among viruses isolated in the same period of time, but without distinct difference in geographical origins.

关 键 词：传染性支气管炎病毒 分离株 S1基因高变区I 序列测定 遗传变异 基因型 

分 类 号：S852.65[农业科学—基础兽医学]