摘要
近年来,鸡传染性支气管炎(IB)在我国广西地区相继暴发,流行十分广泛,给养禽业带来巨大损失。为及时了解传染性支气管炎病毒(IBV)的变异情况,从而进行更有效的防控,本研究对2012年分离自广西的8株IBV的S1基因进行了序列测定与分析。参考NCBI上的IBV S1基因序列,设计合成了一对扩增S1基因全长序列的引物。采用RT-PCR方法对8株IBV分离株(GX1-GX8)的S1基因进行克隆测序。序列分析结果表明,8株IBV分离株S1基因全长均为1620bp,且集中分布在2个分支,GX1-GX4属于第Ⅴ分支,其裂解位点均为RRFRR;GX5-GX8属于第Ⅰ分支,其裂解位点均为HRRRR,为IBV中国毒株所特有。同时,这些分离株进化趋势与其分离时间之间显示出一定的相关性;潜在糖基化位点(PGS)分析结果显示,GX1-GX4的PGS分布一致且与GX5-GX8的分布显示出一定的差异;核苷酸同源性分析结果表明,位于同一分支的毒株间同源性较高,所有分离毒株与我国使用的常规Mass型疫苗毒株的同源性均偏低。这暗示目前广西IBV分离毒株与我国广泛使用的IB疫苗毒株的遗传进化距离较远,常规Mass型疫苗可能起不到很好的免疫保护作用。
Infectious bronchitis virus has caused huge economic losses to poultry industry in the domestic re-cently because of successive and extensive outbreak.In order to master the variation of IBV timely,this study carried out the sequence analysis of isolates from Guangxi.The S1 genes of 8 IBV isolates which were isolated from Guang Xi province of China in 2012 were cloned and sequenced by reverse transcription polymerase chain reaction （RT-PCR）.Sequence analysis showed that the total length of S1 genes of 8 iso-lates was 1 620 bp,and they were classified into 2 branches.GX1-GX4 belongs to V branch,and the cleav-age motifs of them were RRFRR sequences,while GX5-GX8 belongs to branchⅠ,and their cleavage motifs were HRRRR sequences which exhibits characteristics of local pandemic strain in China.The Potential gly-cosylation site （PGS）analysis indicated that GX1-GX4 owned the same PGS distribution while differed from GX5-GX8.Both the homology alignment and phylogenetic classification with reference strains demon-strated that the 8 isolates were evolutionarily distant from all commercial vaccines.
出处
《动物医学进展》
CSCD
北大核心
2014年第3期68-72,共5页
Progress In Veterinary Medicine
基金
广东省教育部产学研结合项目(2012B091100078)
