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HIV-induced membraneless organelles orchestrate post-nuclear entry steps
Viviana Scoca1, Renaud Morin2, Maxence Collard1
1Advanced Molecular Virology Unit, Department of Virology, Institut Pasteur, Université Paris Cité, 75015 Paris, France.
Journal of Molecular Cell Biology
|October 31, 2022
Summary
Human immunodeficiency virus (HIV) hijacks host cells using liquid-liquid phase separation to form HIV-induced membraneless organelles. These structures organize viral replication before integration, creating favorable conditions for viral spread.
Area of Science:
- Cell Biology
- Virology
- Molecular Biology
Background:
- HIV-1 infection remodels the host cell's nuclear landscape.
- The mechanism behind HIV-1-induced clustering of the host factor CPSF6 is not well understood.
Purpose of the Study:
- To investigate the mechanism by which HIV-1 hijacks host cells.
- To explore the role of liquid-liquid phase separation in HIV-1 replication.
Main Methods:
- Observation of CPSF6 clusters within HIV-induced membraneless organelles (HIV-1 MLOs) in macrophages.
- Analysis of HIV-1 MLOs as functional biomolecular condensates following phase-separation rules.
Main Results:
- HIV-1 MLOs act as hubs for nuclear reverse transcription.
- Double-stranded viral DNA rapidly exits HIV-1 MLOs post-formation.
- Transcription-competent proviruses are found near HIV-1 MLOs in active chromatin regions.
Conclusions:
- HIV-1 utilizes liquid-liquid phase separation to form functional HIV-1 MLOs.
- HIV-1 MLOs orchestrate key viral events preceding integration, optimizing viral replication.
- The study reveals functional host-viral complexes within the restructured nuclear environment during HIV-1 infection.
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