This Article Full Text (PDF) Other Versions of this Article: JVI.02359-06v1 81/7/3495    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Jiang, C. Articles by Hwang, C. B. C. Search for Related Content PubMed PubMed Citation Articles by Jiang, C. Articles by Hwang, C. B. C.

 Previous Article  |  Next Article 

J. Virol. doi:10.1128/JVI.02359-06
Copyright (c) 2007, American Society for Microbiology and/or the Listed Authors/Institutions. All Rights Reserved.

Mutations that decrease DNA binding of the processivity factor of the herpes simplex DNA polymerase reduce viral yield, alter the kinetics of viral DNA replication, and decrease fidelity of DNA replication

Department of Microbiology and Immunology, State University of New York Upstate Medical University, Syracuse, NY 13210, and Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115

^* To whom correspondence should be addressed. Email: hwangc{at}upstate.edu.

	Abstract

The processivity subunit of the herpes simplex virus DNA polymerase, UL42, is essential for viral replication, and possesses both Pol- and DNA-binding activities. Previous studies demonstrated that the substitution of alanine for each of four arginine residues, which reside on the positively charged surface of UL42, resulted in decreased DNA binding affinity and decreased ability to synthesize long-chain DNA by the polymerase. In this study, the effects of each substitution on the production of viral progeny, viral DNA replication, and DNA replication fidelity were examined. Each substitution mutant was able to complement the replication of a UL42 null mutant in transient complementation assays, and to support the replication of a plasmid DNA containing HSV-1 origin sequences in transient DNA replication assays. Mutant viruses containing each substitution and a lacZ insertion in a non-essential region of the genome were constructed and characterized. In single cycle growth assays, the mutants produced significantly less progeny virus than a control virus containing wild type UL42. Real time PCR assays revealed that these UL42 mutants synthesized less viral DNA during the early phase of infection. Interestingly, during the late phase of infection, the mutant viruses synthesized higher amounts of viral DNA than the control virus. The frequencies of mutations in the virus-borne lacZ gene increased significantly in the substitution mutants, compared to those observed with the control virus. These results demonstrate that the reduced DNA binding of UL42 is associated with significant effects on virus yields, viral DNA replication, and replication fidelity. Thus, a processivity factor can influence replication fidelity in mammalian cells.

This article has been cited by other articles:

• Jiang, C., Hwang, Y. T., Wang, G., Randell, J. C. W., Coen, D. M., Hwang, C. B. C. (2007). Herpes Simplex Virus Mutants with Multiple Substitutions Affecting DNA Binding of UL42 Are Impaired for Viral Replication and DNA Synthesis. J. Virol. 81: 12077-12079 [Abstract] [Full Text]