PRRSV强、弱毒株Nsp9基因对PRRSV复制的影响

摘要

In order to verify the difference of gene Nsp9 between virulent strain and low virulent strain whether could enchance the replication of PRRSV,plasmids pIRes2-EGFP-Nsp9-XH-GD and pIRes2-EGFP-Nsp9-CH-1R containing whole Nsp9 genome were transfected into Marc-145 cells,qPCR and Western Blot were conducted to e valuate its titer and expression after PRRSV was inoculated,the results showed that the level of N protein in the cells that were transfected with low virulent strain CH-1R Nsp9 gene was higher than the control group-virulent strain XH-GD in the mRNA level.Meanwhile,on the protein level,it was the same as the mRNA level,and virus titer was also higher than virulent strain.It demonstrated that Nsp9 gene of low virulent strain CH-1R in the Marc145 cells was more beneficial to the replication of PRRSV than that of virulent strain XH-GD.%为了探索猪繁殖与呼吸综合征病毒(PRRSV)强、弱毒株的Nsp9基因对PRRSV复制的影响,构建含有PRRSV XH-GD强毒株、CH-1R弱毒株Nsp9全长基因的质粒pIRes2-EGFP-Nsp9-XH-GD、pIRes2-EGFP-Nsp9-CH-1R,并将重组质粒分别转染到Marc-145细胞中,以MOI=1的剂量接种PRRSV XH-GD毒株,通过TCID50试验测定病毒的滴度,采用荧光定量PCR和Western Blot方法来测定病毒的N蛋白表达情况.结果表明,转染弱毒株CH-1R Nsp9基因的Marc-145细胞中,PRRSV的N蛋白在mRNA水平、蛋白质水平上的表达量均高于转染强毒株XH-GD组,且病毒的滴度也显著高于转染强毒株XH-GD组.综上,在Marc-145细胞中,弱毒株CH-1R Nsp9基因对PRRSV复制的促进作用优于强毒株XH-GD.