Characterization of the antiapoptotic (p35) gene homologue of Spodoptera litura nucleopolyhedrosis virus (SlNPV)

Antiapoptotic genes of baculoviruses have been shown to prevent virus induced apoptosis in insect cells. Dot blot and Southern hybridizations of EcoRI genomic library and genomic digests of Spodoptera litura nucleopolyhedrosis virus (SlNPV) respectively give strong hybridization signals with antiapoptotic DNA (p35 gene) probe of the prototype Autographa californica nucleopolyhedrosis virus (AcNPV). Both the hybridizations indicate the presence of a homologous gene in the 1.8 kb EcoRI-Y fragment of SlNPV. The sequence of 1.244 kb region of this fragment encompasses an open reading frame coding for a polypeptide of 296 amino acids under sequential early (TATA) and late (TAAG) promoter motifs like that in other baculovirus p35 genes. The putative SlNPV p35 ORF expresses abundantly as a 35 kDa protein in Spodoptera frugiperda (Sf9) cells when allowed to express under the polyhedrin promoter of AcNPV.