2018年四川地区猪繁殖与呼吸综合征病毒ORF5基因的分子流行病学调查研究  

Molecular Epidemiological Investigation on ORF 5 Gene of Porcine Reproductive and Respiratory Syndrome Virus in Sichuan in 2018

作　　者：刘瀚扬 张毅[2] 肖冉 陈斌[2] 吴永胜[1] 苏志鹏 李峪鹏 裴超信[2] 许祯莹[1] 朱佳文 LIU Hanyang;ZHANG Yi;XIAO Ran;CHEN Bin;WU Yongsheng;SU Zhipeng;LI Yupeng;PEI Chaoxin;XU Zhenying;ZHU Jiawen(Institute of Animal Science,Chengdu Academy of Agricultural and Forestry Sciences,Chengdu 611130,China;Sichuan Provincial Center for Animal Disease Control and Prevention,Chengdu 610047,China;Wuhan Center for Animal Disease Control and Prevention,Wuhan 430014,China;Sichuan Tequ Investment Group Co.,Ltd.,Chengdu 610207,China;College of Veterinary Medicine,Sichuan Agricultural University,Chengdu 611130,China)

机构地区：[1]成都市农林科学院畜牧研究所,成都611130 [2]四川省动物疫病预防控制中心,成都610047 [3]武汉市动物疫病预防控制中心,武汉430014 [4]四川特驱投资集团有限公司,成都610207 [5]四川农业大学动物医学院,成都611130

出　　处：《中国畜牧兽医》2020年第4期1172-1182,共11页China Animal Husbandry & Veterinary Medicine

基　　金：四川省科技厅应用基础研究项目(2018JY0252);成都市2018年科研创新和集成应用示范(0202049);成都市2019年科研创新和集成应用示范(0202071)。

摘　　要：为研究四川地区猪繁殖与呼吸综合征病毒(PRRSV)的流行及进化趋势,本研究以GP5蛋白为研究对象,对2018年间收集的378份四川省不同区市县PRRSV疑似病料进行了实时荧光定量PCR检测,并对部分毒株ORF 5基因的核苷酸序列和推导的氨基酸序列进行进化分析和N-糖基化位点预测。通过疑似病料实时荧光定量PCR检测,共检出阳性样品69份,阳性率为18.25%。对其中23株PRRSV的ORF 5基因序列分析结果显示,ORF 5基因之间核苷酸同源性为81.6%~100%,推导的氨基酸同源性为81.4%~100%,均属于美洲型毒株。其中,1株属于以经典毒株VR2332为代表的亚型Ⅰ,17株属于以高致病毒株JXA1为代表的亚型Ⅱ,5株属于重组毒株NADC30为代表的亚型Ⅲ,说明2018年间四川省PRRSV流行毒株存在基因多样性,HP-PRRSV依然是主要流行毒株,但仍存在不断进化的经典毒株,同时,类似NADC30和QYYZ的重组毒株也开始出现。通过氨基酸突变位点和N-糖基化位点分析发现,23株PRRSV在GP5两个重要抗原表位相关区域和毒力相关位点均发生了一定程度的突变,推测这些突变可能影响了病毒逃避机体免疫和病毒毒力,提示在PRRSV防控中,应该加强遗传进化分析,根据不同类型的毒株选择有针对性的疫苗和防控策略。In order to study the epidemic and evolution trend of porcine reproductive and respiratory syndrome virus(PRRSV)in Sichuan,this study took GP5 protein as the research object,detected 378 suspected PRRSV samples collected in different districts,cities and counties of Sichuan province in 2018 by Real-time PCR,and analyzed the nucleotide sequence and deduced amino acid sequence of ORF 5 gene of some strains and predicted the N-glycosylation site.69 positive samples were detected by Real-time PCR,the positive rate was 18.25%.The ORF 5 gene sequence analysis of 23 PRRSV strains showed that the nucleotide homology of ORF 5 gene was 81.6%-100%,and the deduced amino acid homology was 81.4%-100%.All of them belonged to America type.Among them,1 strain belonged to subtypeⅠrepresented by the classic strain VR2332,17 strains belonged to subtypeⅡrepresented by the highly pathogenic strain JXA1,and 5 strains belonged to subtypeⅢrepresented by the recombinant strain NADC30,which indicated that there was genetic diversity of PRRSV epidemic strains in Sichuan province in 2018,HP-PRRSV was still the main epidemic strain,but there were still evolving classic strains.At the same time,recombinant strains which were similar to NADC30 and QYYZ began to appear.Through the analysis of amino acid mutation sites and N-glycosylation sites,it was found that 23 PRRSV strains had some mutations in two important epitope related areas and virulence related sites of GP5.It was speculated that these mutations might affect the virus’s escape from immune system and virus virulence,suggesting that in PRRSV prevention and control,genetic evolution analysis should be strengthened,and selected targeted vaccines and control strategies according to different types of strains.

关 键 词：猪繁殖与呼吸综合征病毒(PRRSV) 分子流行病学 ORF 5基因 变异分析 

分 类 号：S852.65[农业科学—基础兽医学]