Fengxue Wang;Yan Wen;Zhun Liu;Xue Leng;Zhenguang Li;Hua W

State Key Laboratory for Molecular Biology of Special Economic Animals,Institute of Special Animal and Plant Sciences,Chinese Academy of Agricultural Sciences,Changchun 130122,Chin;State Key Laboratory for Molecular Biology of Special Economic Animals,Institute of Special Animal and Plant Sciences,Chinese Academy of Agricultural Sciences,Changchun 130122,China

nsp2;145;marc;tj;tjm;prrs

[Objective]The study aimed to investigate the effects of Nsp2 protein on porcine reproductive and respiratory syndrome virus ( PRRSV) replication. [Method]Through in vitro cloning,the Nsp2 gene of highly pathogenic PRRSV TJ and attenuated TJM were amplified by RT-PCR and cloned into the plasmid pEGFP-N1,which containing enhanced green fluorescent protein expression box. The constructed plasmids pEGFP-TJ Nsp2 and pEGFP-TJM Nsp2 were transfected into Marc-145 cells and screened by G418. Anti-G418 Marc-145-TJ Nsp2 and Marc-145-TJM Nsp2 cells were obtained,and the expression of Nsp2 protein in anti-G418 Marc-145-TJ Nsp2 and Marc-145-TJM Nsp2 cells was proved by PCR and RT- PCR. The Marc-145-TJ Nsp2 and Marc-145-TJM Nsp2 cells were infected by PRRSV,and TCID 50 was determined. [Result]The cells expressing Nsp2 gene of highly pathogenic PRRSV TJ and attenuated TJM,Marc-145-TJ Nsp2 and Marc-145-TJM Nsp2,were stable. PRRSV replication was fast in early stage on these cells. That is to say,Nsp2 protein played a positive role in early phase of PRRSV proliferation,and the effect of Nsp2 protein of highly pathogenic PRRSV TJ was more obvious. [Conclusion]The construction of Marc-145-Nsp2 cell lines provided data for the further discuss of PRRSV replication mechanism.