广西PRRSV分离株Y12018全基因组扩增和遗传进化分析

Whole genome sequencing and phylogenetic analysis of Y12018 porcine reproductive and respiratory syndrome virus isolated from Guangxi Province

为监测广西地区猪繁殖与呼吸系统综合征病毒(PRRSV)的流行和变异情况,本研究从广西某猪场采集样本成功分离获得PRRSV毒株并命名为Y12018,并参考扩增全长所需的10对特异性引物对其全基因组序列分段扩增后连接,为进一步鉴定Y12018毒株,将Nsp2与GP5等序列分别与参考毒株进行对比,分析该分离株与国内外典型毒株的遗传进化关系从而探究其基因组来源。结果显示,Y12018毒株基因组全长为15 017 bp(除去polyA尾),与NADC30毒株遗传关系最为接近,全基因组同源性为94.4%;Nsp2同源性为96.8%,与NADC30相比缺失的2个氨基酸,对应VR-2332为587~588位点;GP5同源性为93.5%,对应氨基酸序列有31个位点发生改变;其余各开放阅读框的同源性为92.9%~97.1%;遗传演化分析结果表明分离株Y12018属于类NADC30毒株。

In order to monitor the prevalence and molecular variation characteristics ofporcine reproductive and respiratory syndrome virus(PRRSV) in Guangxi Province, a PRRSV strain named Y12018 was isolated from a pig farm in Guangxi Province.Ten pairs of primers were designed according to the PRRSV NADC30-like strain, and the whole genome sequence of the Y12018 strain was amplified and sequenced.To further identify the Y12018 strain and explore the source of its genome, the sequences of Nsp2 and GP5 genes was compared with the reference strains from China and the other countries.The results showed that the genome length of Y12018 strain was 15 017 bp(excluding ployA tail).Moreover, phylogenetic analysis showed that the Y12018 strain had closer relationship with NADC30-like stain, the whole gene homology was 94.4%,the sequence homology of Nsp2 was 96.8% and 2 amino acids were deleted, the corresponding sites for VR-2332 were 587 and 588.The sequence homology with GP5 was 93.5% and 31 amino acid sequences changed, the homology of the remaining open reading frames(ORF) was between 92.9% and 97.1%.The genetic evolution analysis results show that PRRSV Y12018 is NADC30-like strain.