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Determining 3'-Termini and Sequences of Nascent Single-Stranded Viral DNA Molecules during HIV-1 Reverse Transcription in Infected Cells
Published on: January 30, 2019
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Structural Insights into APOBEC3-Mediated Lentiviral Restriction.
Krista A Delviks-Frankenberry1, Belete A Desimmie1, Vinay K Pathak1
1Viral Mutation Section, HIV Dynamics and Replication Program, National Cancer Institute at Frederick, Frederick, MD 21702, USA.
Viruses
|May 31, 2020
Summary
Human APOBEC3 (A3) proteins are crucial intrinsic immune factors that restrict HIV-1 replication. The HIV-1 accessory protein Vif counteracts A3 activity through degradation, highlighting a key host-pathogen battle.
Area of Science:
- Immunology
- Virology
- Molecular Biology
Background:
- Mammals possess innate and adaptive immunity against pathogens.
- The APOBEC3 (A3) family of cytidine deaminases are intrinsic restriction factors.
- A3 proteins provide immunity against viruses and retroelements.
Purpose of the Study:
- To review the role of human A3 proteins in restricting HIV-1.
- To explain how HIV-1 Vif protein antagonizes A3 proteins.
- To highlight structural and functional insights into A3-mediated lentiviral restriction.
Main Methods:
- Review of existing literature on A3 proteins and HIV-1.
- Analysis of mechanisms of A3 restriction and Vif antagonism.
- Examination of structural and functional data.
Main Results:
- Four A3 proteins (A3G, A3F, A3H, A3D) restrict HIV-1 without Vif.
- Vif targets A3 proteins for proteasomal degradation.
- A3 incorporation into virions is essential for antiviral activity.
Conclusions:
- Human A3 proteins are significant barriers to HIV-1 infection.
- HIV-1 Vif has evolved to overcome A3-mediated restriction.
- Understanding these interactions offers insights into lentiviral host defense evasion.
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