高致病性猪繁殖与呼吸综合征病毒ORF7基因的克隆与原核表达

Cloning and Prokaryotic Expression of Gene ORF7 of Highly Pathogenic Porcine Reproductive and Respiratory Syndrome Virus

猪繁殖与呼吸综合征(PRRS)是严重危害全球养猪业的重要病毒性传染病。通过PCR方法从高致病性PRRSV WUH1株中扩增得到结构蛋白ORF7的基因片段,并将目的基因插入原核表达载体pET-30a中,得到重组表达质粒pET-30a-ORF7。重组表达质粒转化大肠杆菌BL21(DE3)细胞,经IPTG诱导,SDS-PAGE聚丙烯酰胺凝胶电泳分析表明,融合蛋白得到了高效表达,表达的融合蛋白分子量约20kD。

Porcine reproductive and respiratory syndrome is an important viral infectious disease that severely threatens global pig industry.In this study,the gene sequence of structural protein ORF7 was amplified from highly pathogenic PPRSV isolate WUH1 by PCR and the target gene was inserted into prokaryotic expression vector pET-30a,generating a recombinant expression plasmid,pET-30a-ORF7.The recombinant expression plasmid was then used to transform competent cells of Escherichia coli BL21（DE3）and the expression was induced by IPTG.SDS-PAGE electrophoresis analysis showed an efficient expression of the target fusion protein,of which molecular weight was about 20 kD.