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Updated: May 8, 2026
10:14
Biochemical Assays for Analyzing Activities of ATP-dependent Chromatin Remodeling Enzymes
Published on: October 25, 2014
ATP-dependent chromatin assembly is functionally distinct from chromatin remodeling.
Sharon E Torigoe1, Ashok Patel, Mai T Khuong
1Section of Molecular Biology , University of California, San Diego , La Jolla , United States.
Elife
|August 30, 2013
Summary
Chromatin assembly uses motor proteins for ATP-dependent nucleosome formation. A study reveals distinct roles for Chd1 in assembly versus remodeling, generating periodic nucleosome arrays.
Area of Science:
- Molecular Biology
- Epigenetics
- Chromatin Dynamics
Background:
- Chromatin assembly requires ATP-dependent motor proteins and histone chaperones.
- Motor proteins involved in chromatin assembly also function as chromatin remodeling factors.
- The interplay between chromatin assembly and remodeling in generating periodic nucleosome arrays is not fully understood.
Purpose of the Study:
- To investigate the relationship between ATP-driven chromatin assembly and chromatin remodeling.
- To determine the specific roles of the Chd1 motor protein in these processes.
- To elucidate the mechanism by which periodic nucleosome arrays are generated.
Main Methods:
- Utilized chromatin remodeling-defective Chd1 motor proteins.
- Assessed the ability of wild-type and mutant Chd1 to catalyze ATP-dependent chromatin assembly.
- Analyzed the spacing of nucleosomes in generated arrays.
Main Results:
- Chromatin remodeling-defective Chd1 catalyzed ATP-dependent chromatin assembly, but produced randomly spaced nucleosomes.
- Wild-type Chd1, unlike the mutant, converted randomly spaced nucleosomes into periodic arrays.
- Demonstrated a functional distinction between ATP-dependent nucleosome assembly and chromatin remodeling activities of Chd1.
Conclusions:
- Chd1 possesses separate functions for nucleosome assembly and chromatin remodeling.
- A model is proposed where Chd1 first assembles random nucleosomes, then remodels them into periodic arrays.
- These findings highlight novel specificity in motor protein roles during chromatin organization.
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