GENETIC ORGANIZATION OF THE HINDIII-I REGION OF THE SINGLE-NUCLEOCAPSID NUCLEOPOLYHEDROVIRUS OF BUZURA-SUPPRESSARIA

In order to investigate the genomic organization of the single-nucleoc apsid nucleopolyhedrovirus (SNPV) of Buzura suppressaria (BusuNPV), th e HindIII-I fragment located at map units (mu) 26.6-29.4 of the viral genome was sequenced. The fragment contained two partial and three com plete open reading frames (ORFs) representing the 3' end of a polyhedr on envelope protein gene (pep), a homologue of the AcMNPV ORF117, a co notoxin-like protein gene (ctl), an inhibitor of apoptosis gene (iap) and a superoxide dismutase gene (sod), respectively. These five genes were identified for the first time in a SNPV. Sequence analysis furthe r revealed that these ORFs have the same conserved motifs and gene str ucture as those observed in their homologues from other baculoviruses. Between ctl and lap, an intergenic region of about 700 basepairs with structure similar to non-hr origins of DNA replication was observed. The genomic arrangement of the ORFs in the BusuNPV HindIII-I fragment is very different from the arrangement of their homologues in the geno me of Autographa californica multiple nucleocapsid (M) NPV and other b aculoviruses to date. Our data suggest that on the basis Of gene arran gement, BusuNPV belongs to a distinct taxon within the Baculoviridae f amily, corroborating our previous conclusions derived from phylogeny a nalysis of several BusuNPV genes. (C) 1998 Elsevier Science B.V. All r ights reserved.