Sequence, Transcription and Translation of a Late Gene of the Autographa californica Nuclear Polyhedrosis Virus Encoding a 34.8K Polypeptide

Abstract

SUMMARYA 1 "4 kb region downstream of the DNA polymerase gene of Autographa californica nuclear polyhedrosis virus was sequenced. Two open reading frames (ORFs) were identified of 927 and 474 bases in length. The 927 base ORF encodes a 34.8K protein as determined by in vitro translation of both hybrid-selected RNA and RNA synthesized in vitro from a 927 base ORF template. The predicted amino acid sequence of the 34.8K polypeptide (p34.8) reveals a hydrophobic N terminus, two potential N-glycosylation sites, and potential sites for phosphorylation by casein kinase I and protein kinase C. The p34.8 gene has a strong codon usage bias which is strikingly different from that of the polyhedrin gene. The two 5' ends of the 927 base ORF transcripts initiate from an ATAAG sequence and a GTAAG sequence 11 and 87 bases upstream of the ATG codon respectively. A short upstream reading frame is present in the leader sequence of the longer RNA. The transcripts have multiple 3' ends; the most proximal endpoint correlates with a polyadenylation signal overlapping the translational termination codon of the 927 base ORF. Transcripts of the latter were not observed early in the infection cycle but appeared 6 h after infection and were maximally expressed at 12 to 24 h post-infection. The late nature of these transcripts was confirmed by their sensitivity to aphidicolin and cycloheximide, inhibitors of DNA replication and protein synthesis respectively. Attempts to construct viral mutants carrying a deletion of the p34.8 gene and fusion with the fl-galactosidase gene suggest that the former gene is essential for viral replication.

Molecular analysis of the p48 gene of Choristoneura fumiferana multicapsid nucleopolyhedroviruses CfMNPV and CfDEFNPV.

“…The collective data presented here suggest that ORF p48 may be needed for virus replication and attempts to inactivate it would result in an abortive infection. A similar conclusion, based on the inability to generate a gp34.8 null AcMNPV, was reached by Wu & Miller (1989).…”

Identification and expression of two baculovirus gp37 genes.

“…The alignments were generated by using CLUSTAL W (Thompson et al, 1994) and shaded using GeneDoc (K. B. Nicholas & H. B. Nicholas, personal communication) with shading levels set at 100 %, 80-99 % and 60-79 % conserved residues. The sequences used were : acgp37, AcMNPV GP37 (Wu & Miller, 1989) ; bmgp37, BmNPV GP37 (GenBank accession no. L33180) ; cfgp37, CfMNPV GP37 (U26734) ; opgp37, OpMNPV GP37 (Gross et al, 1993) ; mbgp37 and ldgp37, this paper ; lsgp37, Leucania separata NPV GP37 (AB009614) ; ancuepvfus, AncuEPV fusolin (Mitsuhashi et al, 1997) ; mmepvfus, MmEPV fusolin (Gauthier et al, 1995) ; haepvfus, HaEPV fusolin (Dall et al, 1993) ; psepvfus, PsEPV fusolin (Hayakawa et al, 1996) ; cbepvfus, CbEPV fusolin ; pschib, Pseudoalteromonas Chi B (AF007895) ; and shcbp, Streptomyces halstedii CBP (Garda et al, 1997).…”

Recent Advances in Our Knowledge of Baculovirus Molecular Biology and Its Relevance for the Registration of Baculovirus-Based Products for Insect Pest Population Control

“…AcMNPV genes encoding structural proteins of nucleocapsids and BVs are transcribed at their peak during the late phase (6 -24 hpi), while occlusion-related genes are transcribed at very late times post-infection (18 -76 hpi) (Thiem & Miller, 1990;Wu & Miller, 1989). The increase in late viral transcription parallels the decline in host and early viral transcription (Nobiron et al, 2003).…”