THE GENE ENCODING THE CAPSID PROTEIN P82 OF THE CHORISTONEURA-FUMIFERANA MULTICAPSID NUCLEOPOLYHEDROVIRUS - SEQUENCING, TRANSCRIPTION AND CHARACTERIZATION BY IMMUNOBLOT ANALYSIS

A gene encoding a capsid-associated viral structural protein has been identified and sequenced in the genome of the Choristoneura fumiferana multicapsid nucleopolyhedrovirus (CfMNPV), The gene has a 1872 nucleo tide open reading frame (ORF) encoding 624 amino acids with a predicte d molecular mass of 71.4 kDa, Transcription, which appeared to be init iated from a conserved GTAAG motif of baculovirus late genes, was dete cted at 12 h, reached a maximum at 48 h and declined at 72 h post-infe ction (p.i.), Part of the ORF was cloned in frame into a prokaryotic e xpression vector, pMAL-c2, and the fusion protein was used to generate antibodies in rabbits. it was shown, with the aid of the polyclonal a ntiserum, that this viral protein was detectable at 24 h p.i. in infec ted cells. The protein appeared as an 82 kDa band in occlusion-derived virus and as an 82 kDa band and a 72 kDa band in budded virus, Amino acid sequence comparisons revealed that this ORF had high homology wit h the ORF p87 (77% similarity) of Orgyia pseudotsugata (Op) MNPV and t he ORF p80 (60% similarity) of Autographa californica (Ac) MNPV, Immun oblots confirmed that the CfMNPV protein had antigenic similarities to the P87 protein of OpMNPV, but not to the P80 of AcMNPV.