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Updated: Jul 8, 2026
11:28
Dissecting Host-virus Interaction in Lytic Replication of a Model Herpesvirus
Published on: October 7, 2011
Herpesvirus papio 2 encodes a virion host shutoff function
John E Bigger1, David W Martin
1Department of Virology and Immunology, Southwest Foundation for Biomedical Research, Texas 78227-5301, USA.
Virology
|December 20, 2002
Summary
Herpesvirus papio 2 (HVP-2) in baboons mimics human herpes simplex virus (HSV) infections. A key viral gene, vhs, was identified, which shuts down host cell protein synthesis and degrades mRNA.
Area of Science:
- Virology
- Molecular Biology
- Immunology
Background:
- Herpesvirus papio 2 (HVP-2) infection in baboons causes disease analogous to human herpes simplex virus (HSV) infections.
- HVP-2 virions possess a factor that rapidly inhibits host cell protein synthesis post-infection.
- This inhibition correlates with the degradation of cellular messenger RNA (mRNA) species.
Purpose of the Study:
- To molecularly characterize the HVP-2 virion host shutoff (vhs) gene homolog.
- To investigate the role of the HVP-2 vhs gene in inhibiting host protein synthesis and degrading mRNA.
- To establish the HVP-2 baboon model for studying vhs function and developing vhs-deficient virus vaccines.
Main Methods:
- Southern blot and DNA sequence analysis to identify the HVP-2 vhs gene homolog.
- Comparison of the HVP-2 vhs gene sequence with those of HSV-1 and HSV-2.
- Disruption of the HVP-2 vhs open reading frame to assess its function.
Main Results:
- A HVP-2 gene with significant sequence identity (>70%) to HSV vhs genes was identified.
- Disruption of the HVP-2 vhs gene significantly reduced the virus's ability to shut off protein synthesis.
- The disruption also diminished the degradation of cellular mRNA, confirming the gene's role in vhs activity.
Conclusions:
- The HVP-2 vhs gene homolog is responsible for the virion host shutoff activity observed in HVP-2 infections.
- The HVP-2 baboon model offers a valuable system for studying the biological significance of vhs in a natural primate host.
- This model can be utilized for preclinical testing of vaccines based on vhs-deficient viruses.
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