NUCLEOTIDE-SEQUENCE AND TRANSCRIPTIONAL ANALYSIS OF THE P10 GENE OF SPODOPTERA-EXIGUA NUCLEAR POLYHEDROSIS-VIRUS

The p10 gene of Spodoptera exigua multiple nuclear polyhedrosis virus (SeMNPV) was localized on the XbaI fragment H (5.1 kb) of the physical map of the viral genome. The coding sequence of the SeMNPV p 10 gene is 264 nucleotides (nt) long corresponding to a predicted protein of 8 8 amino acids with an M(HF) of 9607. The SeMNPV p10 protein showed onl y limited amino acid identity (39% and 26%, respectively) to those of Orgyia pseudotsugata MNPV (OpMNPV) and Autographa californica MNPV (Ac MNPV) and thus appears less conserved than other viral proteins. The S eMNPV p10 gene was expressed by a transcript of approximately 450 nt, which started in the conserved baculovirus late gene promoter motif TA AG. The leader of the SeMNPV p10 transcript was AT-rich (92 %) and at 36 nt was the shortest leader of all baculovirus major late genes repo rted so far. The SeMPNV p10 transcript terminated 6 nt downstream from a putative poly(A) signal sequence (AATAAA); the latter was 61 nt dow nstream of the translational stop codon TAA. Upstream and downstream o f the p10 gene, partial putative ORFs were found that showed significa nt amino acid sequence identity to the baculovirus p26 and p74 protein s. It is concluded that the region of SeMNPV DNA containing the p10 ge ne is collinear with the corresponding regions in the AcMNPV and OpMNP V genomes.