猪传染性胃肠炎病毒疫苗株S基因的克隆及其与流行株的比对分析

目的] 分析猪传染性胃肠炎病毒（porcine transmissible gastroenteritis virus,TGEV）疫苗株和流行株S基因的遗传变异特征。方法] 利用RT-PCR方法对国内目前广泛使用的TGEV疫苗株A、B、C的S基因进行克隆并测序,将获得的序列与近年来公开发表的分离自不同地区的TGEV 毒株S基因序列进行比对分析;选取NCBI中登录号为AF104420.1-Britain、AY587882.1-Nanjing、DQ811786.2-America、EU074218.2-Harbin、FJ755618.2-Harbin、JQ700304-fuzhou、KC609371.1-Shanghai、KX900411.1-United States、M94099.1-Spain和MK272773.1-Fushun 的TGEV 流行株S基因序列,与疫苗株A、B、C的S基因序列一起,利用MegAlign软件进行比对分析。结果] 疫苗株A、B、C的S基因序列两两间的同源性均在96.7%以上;疫苗株A、B、C的S基因序列与NCBI中流行株S基因序列的同源性分别在94.43%~99.82%、95.30%~99.64%、93.48%~98.38%;由遗传进化树可知,疫苗株A、C与国外流行株M94099.1-Spain在同一分支上,疫苗株B与国内流行株JQ700304-fuzhou在另一分支上。结论] TGEV疫苗株的S基因与流行株同源性较高,变异性不大。

Cloning of S Genes from Porcine Transmissible Gastroenteritis Virus Vaccine Strains and Sequence Comparison with Epidemic Strains

Objective] To characterize the genetic variations of S gene in vaccine strains and epidemic strains of porcine transmissible gastroenteritis virus （TGEV）. Method] The S genes from the commonly used TGEV vaccine strains of A, B and C in China were cloned by RT-PCR assay and subsequently sequenced. The obtained sequences were genetically compared with the published S gene sequences of TGEV strains isolated from different regions in recent years. The S gene sequences from TGEV vaccine strains of A, B,C and TGEV epidemic strains published in NCBI with accession numbers of AF104420.1-Britain, AY587882.1-Nanjing, DQ811786.2-America, EU074218.2-Harbin, FJ755618.2-Harbin, JQ700304-fuzhou, KC609371.1-Shanghai, KX900411.1-United States, M94099.1-Spain and MK272773.1-Fushun were genetically assessed with MegAlign software. Result] The homologies of S gene sequences among vaccine strains of A, B and C were all above 96.7%, and those among vaccine strains of A, B, C and the epidemic strains published in NCBI were 94.43%-99.82%, 95.30%-99.64% and 93.48%-98.38%, respectively. The phylogenetic trees demonstrated that vaccine strains of A and C as well as abroad epidemic strain of M94099.1-Spain were clustered in the same branch, and vaccine strain of B and domestic epidemic strain of JQ700304-fuzhou were clustered in another branch. Conclusion] The S gene sequences of TGEV vaccine strains have high homologies with those of TGEV epidemic strains, indicating minor genetic variations in S gene sequences between vaccine strains and epidemic strains.