猪繁殖与呼吸综合征病毒HB-1(sh)/2002株全基因组分子特征分析

猪繁殖与呼吸综合征病毒(porcine reproductive and respiratory syndrome virus,PRRSV)可引起妊娠母猪流产,早产,产死胎、弱胎、木乃伊胎及仔猪和肥育猪的呼吸道症状.最先于20世纪80年代末期爆发于美国和欧洲一些国家,随后很快传至全世界,给世界养猪业造成了巨大的损失.我国在1995年底爆发该病,之后蔓延到我国很多省份.1996年郭宝清、杨汉春等分别从疑似PRRS的病例中分离出PRRSV1,2].

Molecular Characteristics of Complete Genome of a Chinese Porcine Reproductive and Respiratory Syndrome Virus HB- 1(sh)/2002

A full-length genome of a Chinese porcine reproductive and respiratory syndrome virus (PRRSV) isolate and designated as HB-1(sh)/2002,was sequenced and analyzed. The size of complete genome for the isolate is 15,411 nucleotides obtained from a set of overlapping cDNA clones excluding poly A tail,and is comprised of 9 ORFs,two of which encode nonstructural proteins and the others encode the structural proteins. The full-length sequence of HB-1(sh)/2002 was compared with that of two Chinese isolates,BJ-4 and CH-1a.Comparative analysis presented that the complete nucleotide sequence of HB-1(sh)/2002 shared 89.8% and 96.0% identity with BJ-4 and CH-1a,respectively.Compared with the other isolates,it seemed to be more extensive in Nsp2 of nonstructural regions and ORF5 of structural coding regions,respectively.Especially,Nsp2 only shared 77.3% and 89.1% identity with BJ-4 and CH-1a.The ORF5 shared 87.0% and 93.5% identity with BJ-4 and CH-1a.Phylogenetic analysis based on Nsp2 deduced amino acid sequence suggested that HB-1(sh)/2002 belongs to the same subgroup as CH-1a, and Nsp2 can be used as basis for monitoring the genetic variation and typing the PRRSV isolates further.