Affordable Access

deepdyve-link deepdyve-link
Publisher Website

Alternative splicing of the human cytomegalovirus major immediate-early genes affects infectious-virus replication and control of cellular cyclin-dependent kinase.

Authors
  • Du, Guixin
  • Dutta, Nirmal
  • Lashmit, Philip
  • Stinski, Mark F
Type
Published Article
Journal
Journal of Virology
Publisher
American Society for Microbiology
Publication Date
Jan 01, 2011
Volume
85
Issue
2
Pages
804–817
Identifiers
DOI: 10.1128/JVI.01173-10
PMID: 21068259
Source
Medline
License
Unknown

Abstract

The major immediate-early (MIE) gene locus of human cytomegalovirus (HCMV) is the master switch that determines the outcomes of both lytic and latent infections. Here, we provide evidence that alteration in the splicing of HCMV (Towne strain) MIE genes affects infectious-virus replication, movement through the cell cycle, and cyclin-dependent kinase activity. Mutation of a conserved 24-nucleotide region in MIE exon 4 increased the abundance of IE1-p38 mRNA and decreased the abundance of IE1-p72 and IE2-p86 mRNAs. An increase in IE1-p38 protein was accompanied by a slight decrease in IE1-p72 protein and a significant decrease in IE2-p86 protein. The mutant virus had growth defects, which could not be complemented by wild-type IE1-p72 protein in trans. The phenotype of the mutant virus could not be explained by an increase in IE1-p38 protein, but prevention of the alternate splice returned the recombinant virus to the wild-type phenotype. The lower levels of IE1-p72 and IE2-p86 proteins correlated with a delay in early and late viral gene expression and movement into the S phase of the cell cycle. Mutant virus-infected cells had significantly higher levels of cdk-1 expression and enzymatic activity than cells infected with wild-type virus. The mutant virus induced a round-cell phenotype that accumulated in the G(2)/M compartment of the cell cycle with condensation and fragmentation of the chromatin. An inhibitor of viral DNA synthesis increased the round-cell phenotype. The round cells were characteristic of an abortive viral infection.

Report this publication

Statistics

Seen <100 times