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Title: Histone H4 Tails in Nucleosomes: a Fuzzy Interaction with DNA
Abstract

The interaction of positively charged N‐terminal histone tails with nucleosomal DNA plays an important role in chromatin assembly and regulation, modulating their susceptibility to post‐translational modifications and recognition by chromatin‐binding proteins. Here, we report residue‐specific15N NMR relaxation rates for histone H4 tails in reconstituted nucleosomes. These data indicate that H4 tails are strongly dynamically disordered, albeit with reduced conformational flexibility compared to a free peptide with the same sequence. Remarkably, the NMR observables were successfully reproduced in a 2‐μs MD trajectory of the nucleosome. This is an important step toward resolving an apparent inconsistency where prior simulations were generally at odds with experimental evidence on conformational dynamics of histone tails. Our findings indicate that histone H4 tails engage in afuzzy interactionwith nucleosomal DNA, underpinned by a variable pattern of short‐lived salt bridges and hydrogen bonds, which persists at low ionic strength (0–100 mM NaCl).

 
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NSF-PAR ID:
10236629
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie
Volume:
133
Issue:
12
ISSN:
0044-8249
Page Range / eLocation ID:
p. 6554-6561
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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