Prokaryotic Expression and Identification of Nucleocapsid Gene of Canine Distemper Virus CDV-FOX-TA Strain From Fox

The high conservative sequence of Canine Distemper Virus(CDV) N gene was amplified with RT-PCR,cloned into pMD18-T vector,and then constructed into upstream site of His Tag coding sequence in prokaryotic expression vector pET24b.The N fusion protein was highly expressed when the recombinant plasmid was transformed E.coli Rosetta 2(DE3) strain and induced with IPTG.SDS-PAGE and Western blot showed the 15kDa expressed products reacted with standard positive serum against CDV.An indirect ELISA demonstrated recombinant expressed protein had good antigencity and can distinguish effectively anti-CDV positive serum and negative serum.The results showed expressed CDV N protein had similarity of antigencity with natural N protein,and can be used as diagnosis antigen.It provided evidence for establishment of an indirect ELISA method for CDV detection.