Temporal analysis and spatial mapping of Lymantria dispar nuclear polyhedrosis virus transcripts and in vitro translation polypeptides

Abstract

SummaryGenomic expression of the Lymantriu dispar multinucleocapsid nuclear polyhedrosis virus (LdMNPV) was studied. Viral specific transcripts expressed in cell culture at various times from 2 through 72 h postinfection were identified and their genomic origins mapped through Northern analysis. Sixty-five distinct transcripts were identified in this analysis. Most viral transcripts were expressed late in infection, and originated from throughout the viral genome. Viral polypeptides expressed in infected 652Y cells were labeled with [35S]methionine and identified by autoradiography after separation by SDS polyacrylamide gel electrophoresis. Viral protein synthesis was found to occur in a sequential manner. Four proteins were identified in the early phase of viral replication (4-12 h p.i.), 24 proteins in the intermediate phase (12-24 h p.i.), and 5 proteins during the late phase ( > 24 h p.i.1. Gytoplasmic RNAs were isolated from LdMNPV infected cells at 16, 24, and 48 h p.i., and used for hybrid selections with overlapping DNA fragments that covered the entire MMNPV genome. The selected RNAs were translated in vitro, and 61 distinct viral polypeptides were identified and their genomic origins mapped. Temporal and spatial transcription and translation maps of the LdMNPV genome were generated with these data, and the expression pattern of the MMNPV genome was compared to that of the Autograph culifornicu nuclear polyhedrosis virus.

Identification and characterization of an early gene in the Lymantria dispar multinucleocapsid nuclear polyhedrosis virus

“…Early viral transcripts had previously been mapped to this genomic region (Slavicek, 1991). One eDNA clone (274) which hybridized to this probe was identified and contained an insert of approximately 750 bp (data not shown).…”

“…The viral genome of LdMNPV has been cloned and mapped with restriction endonucleases (Riegel et al, 1994;Smith et al, 1988), and transcription and translation maps have been generated (Slavicek, 1991). A number of LdMNPV genes that are also present in D. S. Bischoff and J. M. Slavicek AcMNPV have been identified and characterized, including ecdysteroid UDP-glucosyl transferase (Riegel et al, 1994), DNA polymerase (Bjornson et al, 1992), polyhedral envelope (Bjornson & Rohrmann, 1992a), polyhedrin (Smith et al, 1988), p39 nucleocapsid (Bjornson & Rohrmann, 1992b) and viral protein kinase (Bischoff & Slavicek, 1994).…”

“…Cell cultures were inoculated with LdMNPV clonal isolate 5-6 (Slavicek, 1991) at an m.o.i, of 10. Virus was removed after a 1 h adsorption period and replaced with fresh medium.…”

Properties of two Lymantria dispar nuclear polyhedrosis virus isolates obtained from the microbial pesticide Gypchek

“…The disruption of a single gene has been shown to be sufficient to generate the FP phenotype in AcMNPV (1). It is likely that generation of FP mutants in LdMNPV and in AcMNPV occurs in the same way, since the genomes of these viruses are similar (5; for a review of AcMNPV, 7,23,25,26). The isolation of a LdMNPV FP mutant and the elucidation of the basis of the FP phenotype are prerequisite to efforts directed to prevent the genesis of this mutation during cell culture passage.…”

The First Record of Nucleopolyhedrovirus Isolated from the Gypsy Moth, Lymantria dispar (Lepidoptera, Lymantriidae) in Turkey

“…It is currently being utilized as a biopesticide against the gypsy moth, Lymantria dispar. LdMNPV is the alternative control agent of environmentally sensitive areas because it only affects the gypsy moth (12). While there is considerable interest in the different isolates of LdMNPV in order to find a more effective strain, there is no record of natural isolation and characterization of this virus from Turkey.…”