Herpes Simplex Virus is Akt-ing in translational control
1Department of Microbiology and Immunology, Stanford University School of Medicine, California 94305, USA.
Genes & Development
|December 3, 2010
Summary
Herpes Simplex Virus-1 uses its Us3 kinase to mimic Akt, inhibiting TSC2 and activating mTORC1. This viral strategy enhances mRNA translation, aiding viral protein production.
Area of Science:
- Virology
- Molecular Biology
- Cellular Biology
Background:
- Viruses rely on host protein synthesis machinery.
- Viruses employ strategies to evade host defenses that inhibit protein synthesis.
Purpose of the Study:
- To investigate how Herpes Simplex Virus-1 (HSV-1) overcomes host innate immune responses that suppress protein synthesis.
Main Methods:
- The study focused on the role of the viral kinase Us3 in counteracting host responses.
- Investigated the interaction between Us3, Akt, TSC2, and mTORC1 pathways.
Main Results:
- HSV-1 Us3 kinase phosphorylates and represses tuberous sclerosis complex 2 (TSC2).
- This action leads to the activation of the mammalian target of rapamycin complex 1 (mTORC1) pathway.
- Activation of mTORC1 enhances viral mRNA translation.
Conclusions:
- HSV-1 Us3 kinase acts as an immune evasion mechanism by hijacking the host's mTORC1 pathway.
- This viral strategy ensures efficient viral protein production despite host-imposed restrictions.
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