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Nuclear Import of HIV-1
Qi Shen1, Chunxiang Wu1, Christian Freniere1
1Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA.
Viruses
|November 27, 2021
Summary
The human immunodeficiency virus type 1 (HIV-1) capsid enters the nucleus intact, challenging prior beliefs. This intact capsid protects the viral genome during reverse transcription before uncoating near the integration site.
Area of Science:
- Virology
- Molecular Biology
- Cell Biology
Background:
- Nuclear import of the human immunodeficiency virus type 1 (HIV-1) genome is crucial for infecting non-dividing cells.
- Previous understanding suggested HIV-1 capsid disassembly in the cytosol before nuclear entry due to its size relative to nuclear pore complexes (NPCs).
Purpose of the Study:
- To review recent studies on HIV-1 nuclear import mechanisms.
- To highlight the temporal relationship between viral core nuclear entry, reverse transcription, and capsid uncoating.
Main Methods:
- Review of existing scientific literature and experimental data.
- Analysis of evidence regarding HIV-1 capsid structure and nuclear pore complex interactions.
Main Results:
- Emerging evidence indicates that intact or nearly intact HIV-1 capsids traverse the NPC to enter the nucleus.
- Reverse transcription of the HIV-1 genome occurs within the nucleus, protected by the capsid.
- Capsid uncoating happens during or after viral genome release at the integration site.
Conclusions:
- A new paradigm for HIV-1 nuclear import suggests intact capsid entry, followed by nuclear reverse transcription and later uncoating.
- Understanding this process is vital for developing effective antiviral strategies targeting HIV-1 infection.
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