Dataset Information

Nucleotide sequence and transcriptional analysis of a gene encoding gp41, a structural glycoprotein of the baculovirus Autographa californica nuclear polyhedrosis virus.

ABSTRACT: We have identified and sequenced a region of the Autographa californica nuclear polyhedrosis virus (AcMNPV) genome encoding the major polyhedron-derived virus structural glycoprotein gp41. The open reading frame is located entirely within the AcMNPV SstII-M fragment. The protein sequence does not have hydrophobic regions characteristic of integral membrane proteins and contains a putative O-linked GlcNAc glycosylation site. gp41 is expressed as a late gene, with transcripts starting within two consensus late transcription start sites (TAAG) located immediately upstream of the first methionine codon. A major transcription termination signal is bypassed, possibly generating a bicistronic message. Finally, the nucleotide and protein sequences of AcMNPV and Bombyx mori nuclear polyhedrosis virus are highly conserved.

SUBMITTER: Whitford M

PROVIDER: S-EPMC241303 | biostudies-other | 1992 Aug

REPOSITORIES: biostudies-other

ACCESS DATA

Publications

Nucleotide sequence and transcriptional analysis of a gene encoding gp41, a structural glycoprotein of the baculovirus Autographa californica nuclear polyhedrosis virus.

Whitford M M Faulkner P P

Journal of virology 19920801 8

We have identified and sequenced a region of the Autographa californica nuclear polyhedrosis virus (AcMNPV) genome encoding the major polyhedron-derived virus structural glycoprotein gp41. The open reading frame is located entirely within the AcMNPV SstII-M fragment. The protein sequence does not have hydrophobic regions characteristic of integral membrane proteins and contains a putative O-linked GlcNAc glycosylation site. gp41 is expressed as a late gene, with transcripts starting within two c ...[more]

PMID: 1629955

Similar Datasets

Project description:Baculoviruses are large double-stranded DNA viruses that are virulent pathogens of certain insect species. In a natural host, Trichoplusia ni, infection by the model baculovirus Autographa californica multiple nucleopolyhedrovirus (AcMNPV) begins when the occluded form of the virus disassembles in the midgut and virions infect midgut epithelial cells to establish the primary phase of the infection. To better understand the primary phase of the AcMNPV infection cycle, newly molted 5th-instar T. ni larvae were orally infected with AcMNPV occlusion bodies and the transcriptional responses of the T. ni midgut were analyzed at various times from 0 to 72 h postinfection, using transcriptome sequencing analysis and a T. ni reference genome. The numbers of differentially expressed host genes increased as the infection progressed, and we identified a total of 3,372 differentially expressed T. ni transcripts in the AcMNPV-infected midgut. Genes encoding orthologs of HMG176, atlastin, and CPH43 were among the most dramatically upregulated in response to AcMNPV infection. A number of cytochrome P450 genes were downregulated in response to infection. We also identified the effects of AcMNPV infection on a large variety of genes associated with innate immunity. This analysis provides an abundance of new and detailed information on host responses to baculovirus infection during the primary phase of the infection in the midgut and will be important for understanding how baculoviruses establish productive infections in the organism.IMPORTANCE Baculoviruses are virulent pathogens of a number of important insect pest species. In the host Trichoplusia ni, infection begins in the midgut when infectious virions of the occlusion-derived virus (ODV) phenotype enter and subsequently replicate in cells of the midgut epithelium. A second virion phenotype (budded virus [BV]) is produced there, and BV mediates systemic infection of the animal. Most prior detailed studies of baculovirus infections have focused on BV infections of cultured cells. In this study, we examined the transcriptional responses of the T. ni midgut to infection by ODV of the baculovirus AcMNPV and identified a variety of host genes that respond dramatically to viral infection. Understanding the transcriptional responses of the host midgut to viral infection is critically important for understanding the biphasic infection in the animal as a whole.

Project description:UnlabelledProductive infection of Trichoplusia ni cells by the baculovirus Autographa californica multiple nucleopolyhedrovirus (AcMNPV) leads to expression of ~156 viral genes and results in dramatic cell remodeling. How the cell transcriptome responds to viral infection was unknown due to the lack of a reference genome and transcriptome for T. ni. We used an ~60-Gb RNA sequencing (RNA-seq) data set from infected and uninfected T. ni cells to generate and annotate a de novo transcriptome assembly of approximately 70,322 T. ni unigenes (assembled transcripts), representing the 48-h infection cycle. Using differential gene expression analysis, we found that the majority of host transcripts were downregulated after 6 h postinfection (p.i.) and throughout the remainder of the infection. In contrast, 5.7% (4,028) of the T. ni unigenes were upregulated during the early period (0 to 6 h p.i.), followed by a decrease through the remainder of the infection cycle. Also, a small subset of genes related to metabolism and stress response showed a significant elevation of transcript levels at 18 and 24 h p.i. but a decrease thereafter. We also examined the responses of genes belonging to a number of specific pathways of interest, including stress responses, apoptosis, immunity, and protein trafficking. We identified specific pathway members that were upregulated during the early phase of the infection. Combined with the parallel analysis of AcMNPV expression, these results provide both a broad and a detailed view of how baculovirus infection impacts the host cell transcriptome to evade cellular defensive responses, to modify cellular biosynthetic pathways, and to remodel cell structure.ImportanceBaculoviruses are insect-specific DNA viruses that are highly pathogenic to their insect hosts. In addition to their use for biological control of certain insects, baculoviruses also serve as viral vectors for numerous biotechnological applications, such as mammalian cell transduction and protein expression for vaccine production. While there is considerable information regarding viral gene expression in infected cells, little is known regarding responses of the host cell to baculovirus infection. In these studies, we assembled a cell transcriptome from the host Trichoplusia ni and used that transcriptome to analyze changes in host cell gene expression throughout the infection cycle. The study was performed in parallel with a prior study of changes in viral gene expression. Combined, these studies provide an unprecedented new level of detail and an overview of events in the infection cycle, and they will stimulate new experimental approaches to understand, modify, and utilize baculoviruses for a variety of applications.

Dataset Information

Nucleotide sequence and transcriptional analysis of a gene encoding gp41, a structural glycoprotein of the baculovirus Autographa californica nuclear polyhedrosis virus.

Publications

Nucleotide sequence and transcriptional analysis of a gene encoding gp41, a structural glycoprotein of the baculovirus Autographa californica nuclear polyhedrosis virus.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets