Cloning and Expression of the Nonstructural Protein(NS 1)of the H9N2 Chicken Influenza Virus

Abstract：The nostructural protein(NS 1)encoded by gene 8 of the Influenza virus is present in cells infected with Influenza virus．In this study,NS 1 protein gene of the Chicken influenza virus A／chicken／Beijing／2／97(H9N2)strain was amplified by PCR．The fragment contains EcoR I and Xho I restriction enzyme sites at the ends．The amplified product was cloned into the expression vector pET-30(c)．Recombinant plasmid pET／NS 1 was transformed into E．coli BL2 1(DE3)competent cells an d induced with 0．4 mmol／L IPTG the target protein was produced．the molecular weight of the expressed protein was 30 kDa as expected．Western—blot test indicated that the expressed protein Can react with the NS 1 monoclonal antibody of the influenza virus．This study laid an importan t foundation for H9N2 subtype avian influenza surveillance in China．