摘要
为了解中国山东及周边部分地区自2017年以来猪繁殖与呼吸综合征病毒(PRRSV)流行株的分子流行病学特征、基因组变化规律,作者收集来自山东省、河南省和江苏省的部分猪场采集及送检的疑似PRRS症状猪组织样品70份,利用RT-PCR方法对其进行PRRSV检测。对部分阳性病料中PRRSV的基因重组、决定中国高致病性PRRSV(HP-PRRSV)致病性和复制力的Nsp9第561、586和592位氨基酸等进行分析,以探明该区域PRRSV的遗传演化规律。结果显示,PRRSV检出率为55.7%,从上述样品筛选11株PRRSV分离株。Nsp2序列分析显示,与经典美洲毒株VR-2332相比,7株PRRSV分离株的Nsp2蛋白分别在第481及533-561位发生了30个氨基酸的不连续缺失,这与我国自2006年以来流行的HP-PRRSV的缺失特征相同;2株PRRSV分离株的Nsp2蛋白在481、533-561及595-597位发生了三个部位的共33个不连续氨基酸的缺失;2株PRRSV分离株的Nsp2蛋白在475-518及533-561位出现了两个部位的共73个不连续氨基酸的缺失。该研究中PRRSV分离毒株的Nsp2基因已发生了明显的新型缺失。采用基因重组分析软件RDP4分析显示,以上后4株新型缺失株存在较大的基因重组,且重组部位和重组片段数量不相同;4株病毒均以高致病性毒株JXA1作为重组的主要亲本毒株,多数重组变化集中在Nsp2蛋白区域,在其他非结构蛋白和次要蛋白区域也可见部分重组变化。另外,Nsp9第561、586和592位氨基酸变异分析显示,该4株病毒在上述三个氨基酸位点与中国HP-PRRSV相符。本研究为深入探索PRRSV的遗传变异规律及相关生物学特性研究积累了数据。
In order to investigate the molecular epidemiological characteristics and genomic changes of porcine reproductive and respiratory syndrome virus (PRRSV) epidemic strains from Shandong province and its neighboring areas in China since 2017,in this study,70 samples of suspected PRRS symptoms were collected from some pig farms in Shandong,Henan and Jiangsu provinces,and PRRSV was detected by RT-PCR. The genetic recombination of virus in PRRSV positive samples,the 561st,586th and 592nd amino acids of Nsp9 which determine the pathogenicity and replication of Chinese highly pathogenic PRRSV (HP-PRRSV) were analyzed to explore the genetic evolution of PRRSV isolates. The results showed that 11 strains of PRRSV isolates were screened from the above samples,and the detection rate of PRRSV was 55.7%. Nsp 2 sequence analysis showed that compared with the classical American strain VR-2332,30 amino acids were discontinuously deleted at 481 and 533-561 sites in seven isolates,which were identical to the deletion characteristics of HP-PRRSV prevalent in China since 2006. Two PRRSV isolates had total deletions of 33 discontinuous amino acids in three fragments at 481,533-561 and 595-597,respectively;and two PRRSV isolates showed a total of 73 discontinuous amino acid deletions in two fragments at 475-518 and 533-561,respectively. The Nsp 2 genes of PRRSV mutant strains have undergone significant new deletions. The results of gene recombination analysis by the software RDP4 showed that the last four new type of deleted virus strains had large gene recombination,and the number of recombinant sites and recombinant fragments were different. The four strains all used the highly pathogenic strain JXA1 as the main parental strain for the recombinant and most of the recombination changes were concentrated on Nsp2 protein region,and partial recombination changes were also observed in the non-structural and minor protein regions. In addition,the amino acid variation analysis of positions 561,586 and 592 of Nsp9 showed that the three critical amino acid sites of the four virus isolates were consistent with Chinese HP-PRRSV. This study accumulated data for further exploration of the genetic variation of PRRSV and related biological characteristics.
作者
胡栋
徐煜琳
朱迎春
赵情
王亭亭
庞恒
李传刚
于江
常维山
吴家强
彭军
HU Dong;XU Yulin;ZHU Yingchun;ZHAO Qing;WANG Tingting;PANG Heng;LI Chuangang;YU Jiang;CHANG Weishan;WU Jiaqiang;PENG Jun(Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention,and East China experimental station of Animal Epidemic Pathogen Biology of Ministry of Agriculture of China,College of Animal Science and Veterinary Medicine of Shandong Agricultural University,Tai’an 271018,China;Institute of Animal Science and Veterinary Medicine,Shandong Academy of Agricultural Sciences,Ji’ nan 250100,China)
出处
《畜牧兽医学报》
CAS
CSCD
北大核心
2019年第6期1249-1260,共12页
ACTA VETERINARIA ET ZOOTECHNICA SINICA
基金
国家自然科学基金(31672587)
山东省重点研发计划项目(2016GNC110013)
山东省农科院农业科技创新工程项目(CXGC2016B14)
山东省“双一流”建设项目(SYL2017YSTD11)
