HIV-1 Vif, APOBEC, and intrinsic immunity
Ritu Goila-Gaur1, Klaus Strebel
1Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 4/312, Bethesda, Maryland 20892-0460, USA. rgaur@niaid.nih.gov
Retrovirology
|June 26, 2008
Summary
Human Immunodeficiency Virus type 1 (HIV-1) evades APOBEC proteins, which normally fight retroviruses, using its Vif protein. Vif prevents APOBEC proteins from entering new virus particles, thus enabling HIV-1 replication.
Area of Science:
- Biochemistry
- Virology
- Molecular Biology
Background:
- APOBEC proteins are cellular enzymes that confer immunity against retroviruses and endogenous retroelements.
- Human Immunodeficiency Virus type 1 (HIV-1) has evolved the viral infectivity factor (Vif) protein to counteract APOBEC's antiviral activity.
- APOBEC proteins restrict HIV-1 replication by editing viral DNA or through deaminase-independent mechanisms when Vif is absent.
Purpose of the Study:
- To review the functional interactions between HIV-1, its Vif protein, and the APOBEC3 subfamily.
- To summarize current understanding of APOBEC3-dependent retrovirus restriction mechanisms.
Main Methods:
- This review synthesizes existing research on the molecular mechanisms of Vif-APOBEC3 interactions.
- Analysis of degradation-dependent and -independent pathways employed by Vif to inhibit APOBEC3 activity.
Main Results:
- Vif's primary role is to prevent APOBEC protein encapsidation into nascent virions.
- Vif antagonizes APOBEC3 proteins through both ubiquitin-dependent degradation and degradation-independent mechanisms.
- APOBEC3G and APOBEC3F are key targets of Vif antagonism.
Conclusions:
- Vif is essential for HIV-1 replication by overcoming APOBEC3-mediated antiviral defense.
- Understanding Vif-APOBEC3 interactions is crucial for developing novel antiviral strategies.
- The interplay between Vif and APOBEC3 proteins highlights a critical host-pathogen battleground in retroviral infection.
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