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Generation and Purification of Human INO80 Chromatin Remodeling Complexes and Subcomplexes
Published on: October 23, 2014
ACF, an ISWI-containing and ATP-utilizing chromatin assembly and remodeling factor
1Department of Biology, University of California, San Diego, La Jolla 92093-0347, USA.
Cell
|July 11, 1997
Summary
We purified and characterized ACF, an ATP-dependent factor essential for chromatin assembly and remodeling. ACF facilitates nucleosome array formation and modulates chromatin structure, suggesting a catalytic role in transcriptional activation.
Area of Science:
- Molecular Biology
- Chromatin Dynamics
- Gene Regulation
Background:
- Chromatin structure plays a crucial role in regulating gene expression.
- ATP-utilizing chromatin assembly and remodeling factors are key players in maintaining and altering chromatin architecture.
- ISWI-containing factors, such as NURF, are known to be involved in chromatin organization.
Purpose of the Study:
- To purify and characterize a novel ATP-utilizing chromatin assembly and remodeling factor, termed ACF.
- To investigate the role of ACF in ATP-dependent chromatin assembly and remodeling processes.
- To determine if ACF functions catalytically in chromatin dynamics and transcriptional activation.
Main Methods:
- Purification of the ACF multisubunit factor.
- Biochemical assays for chromatin assembly using purified ACF and histone chaperones (NAP-1, CAF-1).
- Chromatin remodeling assays to assess ACF's effect on internucleosomal spacing and promoter-specific nucleosome reconfiguration (using Gal4-VP16).
Main Results:
- ACF was purified and characterized as a multisubunit factor containing ISWI protein, distinct from NURF.
- Purified ACF, with a histone chaperone, efficiently assembled periodic nucleosome arrays in an ATP-dependent manner.
- ACF demonstrated ATP-dependent modulation of internucleosomal spacing and mediated promoter-specific nucleosome reconfiguration.
Conclusions:
- ACF is a novel ATP-utilizing factor crucial for both chromatin assembly and remodeling.
- ACF acts catalytically in nucleosome array formation and remodeling.
- ACF's functions suggest a significant role in the nucleosome reconfiguration required for transcriptional activation.
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