Structure and Dynamics of a 197 bp Nucleosome in Complex with Linker Histone H1.
Mol Cell
; 66(3): 384-397.e8, 2017 May 04.
Article
em En
| MEDLINE
| ID: mdl-28475873
ABSTRACT
Linker histones associate with nucleosomes to promote the formation of higher-order chromatin structure, but the underlying molecular details are unclear. We investigated the structure of a 197 bp nucleosome bearing symmetric 25 bp linker DNA arms in complex with vertebrate linker histone H1. We determined electron cryo-microscopy (cryo-EM) and crystal structures of unbound and H1-bound nucleosomes and validated these structures by site-directed protein cross-linking and hydroxyl radical footprinting experiments. Histone H1 shifts the conformational landscape of the nucleosome by drawing the two linkers together and reducing their flexibility. The H1 C-terminal domain (CTD) localizes primarily to a single linker, while the H1 globular domain contacts the nucleosome dyad and both linkers, associating more closely with the CTD-distal linker. These findings reveal that H1 imparts a strong degree of asymmetry to the nucleosome, which is likely to influence the assembly and architecture of higher-order structures.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
DNA
/
Cromatina
/
Histonas
/
Nucleossomos
/
Montagem e Desmontagem da Cromatina
Tipo de estudo:
Prognostic_studies
Limite:
Animals
/
Humans
Idioma:
En
Revista:
Mol Cell
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
França