Related Experiment Video
Updated: May 26, 2026
09:38
Identification of Nucleolar Factors During HIV-1 Replication Through Rev Immunoprecipitation and Mass Spectrometry
Published on: June 26, 2019
Repressive LTR nucleosome positioning by the BAF complex is required for HIV latency.
Haleh Rafati1, Maribel Parra, Shweta Hakre
1Department of Biochemistry, Erasmus University Medical Center, Rotterdam, The Netherlands.
Plos Biology
|December 6, 2011
Summary
SWI/SNF complexes BAF and PBAF play opposing roles in HIV latency and activation. BAF maintains latency by positioning nucleosomes, while PBAF promotes transcription upon activation, offering potential therapeutic targets.
Area of Science:
- Virology
- Epigenetics
- Chromatin Biology
Background:
- Latent HIV reservoirs in T cells hinder eradication.
- SWI/SNF chromatin remodelers have complex roles in HIV lifecycle.
- The precise mechanism of SWI/SNF in HIV latency and activation is unclear.
Purpose of the Study:
- Investigate SWI/SNF's role in regulating the latent HIV LTR.
- Elucidate the distinct functions of BAF and PBAF subclasses in HIV latency and reactivation.
Main Methods:
- Analyzed LTR nucleosome occupancy and DNA accessibility.
- Utilized MNase-Seq for high-resolution nucleosome mapping.
- Examined BAF and PBAF recruitment to the HIV LTR before and after activation.
Main Results:
- BAF is required for establishing and maintaining HIV latency by repositioning nucleosomes.
- BAF depletion leads to HIV de-repression and altered LTR nucleosome profiles.
- PBAF is recruited upon activation to facilitate LTR transcription, contrasting BAF's repressive role.
Conclusions:
- BAF and PBAF exhibit opposing functions at the HIV LTR during different infection stages.
- Targeting the BRG1 component of BAF may offer a strategy to eliminate the latent HIV reservoir.
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