广东省PRRSV流行株的分离鉴定及其Nsp2、ORF3、ORF5基因的遗传变异分析  

Isolation and Genetic Variation Analysis of Nsp2、ORF3 and ORF5 of PRRSV from Guangdong Province

作　　者：何锦玲[1,2] 王晶钰[1] 宋长绪[2] 黄忠[1] 蔡汝健[2] 杨鼎[2] 

机构地区：[1]西北农林科技大学动物科技学院,陕西杨凌712100 [2]广东省农业科学院兽医研究所,广东省兽医公共卫生公共实验室,广州510460

出　　处：《中国动物检疫》2009年第6期39-43,共5页China Animal Health Inspection

基　　金：国家食品安全重大专项(2001BA804A31);广东省农业科技攻关项目(2003B21404;20052490100和2006B20301013);广东省自然科学基金(04002083);广东省自然基金重点项目(06105311)

摘　　要：为了探究广东省猪繁殖与呼吸综合征病毒(PRRSV)的流行情况,分析所分离毒株的分子遗传进化特征,本研究用RT-PCR方法对广东11个地区66个养殖场的189份病料进行了PRRSV的检测,结果表明,样本的PRRSV总阳性率为48.7%(92/189),其中变异株占63.0%(58/92);阳性病例样本经处理后接种Marc-145细胞,成功分离到9株PRRSV。对分离到的9个毒株进行ORF3、ORF5基因和Nsp2主要变异区基因的扩增、克隆、测序和遗传变异分析。序列分析结果发现,其中2株Nsp2基因没有缺失,7株病毒的Nsp2基因发生了与高致病性PRRSV毒株相同的缺失,即第481位有一个氨基酸缺失,第532-560位有连续29个氨基酸缺失。同源性分析表明,分离毒株GDYF、GDZC、GDEP、GDSD、GDSH2、GDTH1、GDTH2与国内的HB-1(sh)/2002毒株及其它高致病性PRRSV同源性较高;GDX071108和GDSH1则与VR2332、RespPRRSVMLV、CH-1a的同源性较高,分离株之间的同源性为60.3%-100.0%。系统进化分析发现,GDX071108与PA8和RespPRRSVMLV的亲缘关系很近,与VR2332亲缘关系较近;而GDYF、GDZC、GDEP、GDSD、GDSH2、GDTH1、GDTH2则与JXA1、GD、HUB1、HUB2、HN2、HUN1、HNyz、HEB1、HUN4都在HB-1(sh)/2002的同一分支上。To study the prevalent situation of porcine reproductive and respiratory syndrome virus （PRRSV） in Guangdong province and analyze the genetic variation of the isolated strains, 189 samples from 66 pig farms of 11 areas in Guangdong province were tested by RT-PCR. The result showed that the positive rate was 48.7% （92/189） of all samples, and the variant was 63.0% in the positive samples. The positive samples were inoculated to Marc-145 cells and 9 PRRSV strains were isolated. ORF3, ORF5 and the partial Nsp2 genes of the isolated strains were amplified by RT-PCR, cloned and subjected to homology analysis. Sequence comparision by the DNASTAR （6.0） software showed that the 7 isolated strains had the same deletion with the HP-PRRSV strains in GeneBank, namely Nsp2 had 30 amino acids deletion, and the other 2 isolated strains had no deletion .Homology analysis showed that the GDYF,GDZC,GDEP,GDSD,GDSH2,GDTH1,GDTH2 isolated strains shared a high homology with HB-1 （sh）/2002 and other strains isolated in 2006, such as JXA1 and GD. GDX071108 and GDSH1 shared high homology with VR2332, RespPRRSVMLV and CH-1a. The homology rate of isolated strains were 60.3% to 100.0% . The phylogenetic tree revealed that GDX071108 had closer relationship with PAS, Resp- PRRSVML and VR2332 strains than that of strain CH-1a and HB-1 （sh）. GDYF, GDZC, GDEP, GDSD, GDSH2, GDTH1, GDTH2 had closer relationship with JXA1,GD,HUB1,HUB2,HN2,HUN1,HNyz,HUN4,HEB1.

关 键 词：猪繁殖与呼吸综合征病毒(PRRSV) 分离鉴定 遗传变异分析 

分 类 号：S852.659.6[农业科学—基础兽医学]