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Biochemical Assays for Analyzing Activities of ATP-dependent Chromatin Remodeling Enzymes
Published on: October 25, 2014
Nucleosome mobilization catalysed by the yeast SWI/SNF complex
I Whitehouse1, A Flaus, B R Cairns
1Division of Gene Regulation, University of Dundee, UK.
Nature
|August 31, 1999
Summary
The yeast SWI/SNF complex repositions nucleosomes along DNA through ATP-dependent sliding. This chromatin remodelling mechanism may be a general process for gene regulation.
Area of Science:
- Molecular Biology
- Gene Regulation
- Chromatin Dynamics
Background:
- Gene regulation relies on creating local chromatin structures permissive to transcription.
- The yeast SWI/SNF complex is a key ATP-dependent remodeler of chromatin structure.
- The precise mechanism of SWI/SNF-mediated chromatin disruption remains unclear.
Purpose of the Study:
- To elucidate the pathway by which the yeast SWI/SNF complex remodels chromatin.
- To investigate the mechanism of nucleosome repositioning by SWI/SNF.
Main Methods:
- Utilized a model system to study yeast SWI/SNF complex activity.
- Employed DNA barriers to probe nucleosome displacement mechanisms.
- Analyzed ATP-dependent nucleosome repositioning.
Main Results:
- Demonstrated that yeast SWI/SNF complex repositions nucleosomes in an ATP-dependent manner.
- Showed that nucleosome repositioning favors attachment to acceptor sites on the same DNA molecule (in cis).
- Found that DNA barriers impede SWI/SNF-mediated histone octamer displacement, indicating sliding or tracking.
Conclusions:
- Concluded that SWI/SNF catalyzes nucleosome redistribution along DNA in cis.
- Proposed that SWI/SNF-mediated nucleosome sliding is a general mechanism for ATP-dependent chromatin remodeling.
- Highlighted the importance of SWI/SNF in establishing transcription-permissive chromatin topology.
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