Physical Analysis of Autographa californica Nuclear Polyhedrosis Virus Transcripts for Polyhedrin and 10,000-Molecular-Weight Protein

Abstract

In Autographa californica nuclear polyhedrosis virus-infected cells, polyhedrin, the major structural polypeptide of the viral occlusions, and a low-molecular-weight viral protein with a molecular weight of approximately 10,000 (10K) accumulated to high levels late in infection. Two polyadenylated RNAs 1,200 and 630 bases in size were the most abundant viral transcripts present in the cytoplasm at 48 h postinfection. Evidence is presented that these RNAs were the transcripts for polyhedrin and 10K proteins. The 630-base RNA and five other major polyadenylated RNAs present at 48 h postinfection mapped within or near A. californica nuclear polyhedrosis virus EcoRI-P. The DNA sequences that code for polyhedrin mRNA were examined by S1 nuclease analysis. The polyhedrin gene contained no detectable introns and mapped at 3,990 to 5,200 base pairs to the right of the origin of the circular A. californica nuclear polyhedrosis virus physical map. Heterogeneity at the 5' end of polyhedrin mRNA was observed by using S1 nuclease analysis with 5' end-labeled DNA probes.