Construction of Prokaryotic Expression Vector of N Gene of Canine Distemper Virus

To offer accordance with N protein expression as diagnosis antigen and detecting CDV specific antibody,based on the constructed pMD18-N plasmid containing canine distemper virus N gene,the open reading frame of 1572bp was amplified by polymerase chain reaction(PCR) using one pair of primers.N gene and pET32a(+)were digested with the same procedure,then N gene was cloned into pET32a(+).The positive recombinant plasmid pET32a(+)-N was identified and transformed into E.coli BL21(DE3).The sequencing results showed that N gene was in the correct inserted position and open reading frame,and a fusion protein about 75 kDa was expressed with IPTG.