Analysis of a Recombinant Baculovirus Expressing the Fusion Glycoprotein Gene of the Malaysian Velogenic-Viscerotropic Newcastle Disease Virus Strain AF2240

摘要

The fusion (F) protein of the Newcastle disease virus (NDV) strain AF2240 was cloned into a baculovirus vector derived from the Autographa californica multiple nuclear polyhedrosis virus (AcMNPV) genomic DNA. The Sf9 cells were used to express the F gene upon cotransfection of the baculovirus transfer plasmid and the Bsu36I triple cut AcMNPV genomic DNA using lipid-mediated transfection. The F gene insert was re-amplified from both the recombinant baculovirus DNA (AFrBacF) and mRNA from the infected cells to confirm its transcription in the Sf9 cells. Antigenicity was tested by immunoflourescence, dotblot-immunoassay and western blot analysis with NDV polyclonal antibodies. The Baculovirus-expressed F protein was 6~- kDa in size which corresponds to the uncleaved form of the F protein. The cleavage site of the amplified F gene from the infected cells mRNA was sequenced to rule out any mutational consequences. The AFrBacF virus electron monograph revealed a morphology of the recombinant virus distinct from the wild-type baculovirus.