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Updated: Jul 1, 2026
10:14
Biochemical Assays for Analyzing Activities of ATP-dependent Chromatin Remodeling Enzymes
Published on: October 25, 2014
Histone tails modulate nucleosome mobility and regulate ATP-dependent nucleosome sliding by NURF
Summary
Histone N-terminal tails regulate nucleosome mobility. Removal of the H2B tail promotes sliding, while the H4 tail, specifically residues 16-KRHR-19, is essential for NURF-mediated remodeling.
Area of Science:
- Chromatin biology
- Molecular genetics
- Epigenetics
Background:
- Nucleosome Remodeling Factor (NURF) is an ATP-dependent complex.
- NURF alters chromatin structure via nucleosome sliding, exposing DNA.
- Histone N-terminal tails are unstructured regions influencing chromatin accessibility.
Purpose of the Study:
- To investigate the role of histone N-terminal tails in nucleosome sliding.
- To identify specific histone residues and motifs regulating NURF activity.
Main Methods:
- Reconstitution of hybrid nucleosomes using bacterially expressed Drosophila histones.
- Native gel electrophoresis to assess nucleosome mobility.
- Alanine scanning mutagenesis to probe histone tail function.
Main Results:
- Removal of the histone H2B N-terminal tail promoted uncatalyzed nucleosome sliding.
- Histone H4 N-terminal tail is specifically required for NURF-dependent nucleosome sliding.
- H4 residues 16-KRHR-19 form a critical motif for NURF activity.
- Hyperacetylation did not affect uncatalyzed sliding, but tail location is crucial.
Conclusions:
- Histone N-terminal tails play crucial roles in regulating nucleosome mobility.
- The H4 N-terminal tail, particularly the KRHR motif, is essential for NURF-mediated nucleosome remodeling.
- Histone tail structure and location are functionally important for NURF activity.
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