中国与美国RFLP 1-4-4 lineage1C变异株同一分支PRRSV的全基因组序列分析  

Whole genome sequence analysis of the same subtype branch of lineage1C PRRSV variant(ORF5 RFLP 1-4-4)between China and United States

作　　者：许浒 李超 相丽润 汤艳东[1] 赵静 龚帮俊 李宛生 付军 彭金美[1] 王倩[1] 周国辉[1] 冷超粮[2] 安同庆[1] 蔡雪辉[1] 张洪亮[1] 田志军[1] XU Hu;LI Chao;XIANG Li-run;TANG Yan-dong;ZHAO Jing;GONG Bang-jun;LI Wan-sheng;FU jun;PENG Jin-mei;WANG Qian;ZHOU Guo-hui;LENG Chao-liang;AN Tong-qing;CAI Xue-hui;ZHANG Hong-liang;TIAN Zhi-jun(State Key Laboratory of Veterinary Biotechnology,Harbin Veterinary Research Institute,Chinese Academy of Agricultural Sciences,Harbin 150069,China;Nanyang Normal University,Nanyang 473061,China)

机构地区：[1]中国农业科学院哈尔滨兽医研究所兽医生物技术国家重点实验室,黑龙江哈尔滨150069 [2]南阳师范学院,河南南阳473061

出　　处：《中国预防兽医学报》2022年第2期202-207,共6页Chinese Journal of Preventive Veterinary Medicine

基　　金：国家自然科学基金(32002315);中国博士后科学基金(2020M680788)。

摘　　要：2020年美国报道了高致病性的RFLP 1-4-4 lineage 1C PRRSV变异株,其对猪的致死率达到17.5%。为了分析美国1-4-4 lineage1C PRRSV变异株与中国当前流行的PRRSV的关系,本研究对中国不同基因亚型的PRRSV与美国新发1-4-4 lineage1C PRRSV变异株进行遗传演化分析,结果显示,中国类NADC34 PRRSV与美国RFLP 1-4-4 lineage1C PRRSV变异株关系密切;其Nsp2推导氨基酸序列比对结果显示,中国类NADC34 PRRSV与美国RFLP 1-4-4 lineage1C PRRSV变异株在Nsp2区域存在相同的分子特征,即100个氨基酸(aa328~aa427)的连续缺失。PRRSV基因重组分析结果显示,美国RFLP 1-4-4 lineage1C PRRSV变异株是以类NADC34 IA14737-2016株为母本毒株,并由IA/2014/NADC34和NADC30病毒株提供重组基因片段的重组病毒,而中国早期的类NADC34 PRRSV是以IA/2014/NADC34株为母本毒株的重组病毒。美国早期的类NADC34 PRRSV对仔猪的致病力差异较大,而中国早期的类NADC34 PRRSV对仔猪多为中、低致病力。此外,中国HLJZD22-1812株与美国RFLP 1-4-4 lineage1C PRRSV变异株具有类似的重组模式、相同的Nsp2缺失特征、相同的1-4-4 ORF5限制性片段长度多态性(RFLP)模式,且均属于lineage1C分支。本研究结果首次表明美国RFLP 1-4-4 lineage1C PRRSV变异株与中国类NADC34(PRRSV)属于同一亚型分支,且具有一致的分子特征,提示类NADC34 PRRSV在我国的流行及演化情况需高度关注。In 2020,a highly pathogenic 1-4-4 lineage 1 C PRRSV variant was reported in the United States,and its fatality rate reached 17.5%in piglets.In order to understand the relationship between the 1-4-4 lineage1C PRRSV variants in the United States and the current epidemic PRRSV in China,the genetic evolution of different genotypes of PRRSV in China and the emerged 1-4-4 lineage1C PRRSV variant in the United States were analyzed in this study.Genetic evolution analysis showed that the Chinese NADC34-like PRRSV has a close relationship with the American 1-4-4 PRRSV lineage1C PRRSV variant.The Nsp2 deduced amino acid sequence alignment results showed that the Chinese NADC34-like PRRSV and the American 1-4-4 lineage1C PRRSV variant share the same molecular features that shown a continuous deletion of 100 aa(aa328-aa427)in the Nsp2 region.Recombination analysis showed that the 1-4-4 lineage1C PRRSV is a recombinant virus that NADC34-like strain IA14737-2016 as the parental strain,and the recombination fragments are derived from the IA/2014/NADC34 and NADC30 strains.However,the early NADC34-like PRRSV in China was a recombinant virus that IA/2014/NADC34 virus strain as the major parental strain.Besides,NADC34-like PRRSV in the United States manifested different virulence to piglets in the early stage of virus epidemic,while the virulence of NADC34-like PRRSV in China showed mostly moderate or low virulence to piglets.Furthermore,Chinese HLJZD22-1812 strain shared the same recombination model with American 1-4-4 lineage1C PRRSV variant,which including the identical deletion characteristic in Nsp2 protein,the common 1-4-4 RFLP pattern and the same lineage1C PRRSV branch.The results of this study show that the American 1-4-4 lineage1C PRRSV variant and the Chinese NADC34-like PRRSV belong to the same subtype branch,and have the same molecular characteristics,which suggest that it is necessary to paid close attention to the prevalence and evolution of NADC34-like PRRSV in China.

关 键 词：1-4-4 PRRSV变异株 类NADC34 PRRSV 100个氨基酸缺失 重组病毒 

分 类 号：S852.65[农业科学—基础兽医学]