Structural basis for the recognition of histone H4 by the histone-chaperone RbAp46.
Structure
; 16(7): 1077-85, 2008 Jul.
Article
em En
| MEDLINE
| ID: mdl-18571423
ABSTRACT
RbAp46 and RbAp48 (pRB-associated proteins p46 and p48, also known as RBBP7 and RBBP4, respectively) are highly homologous histone chaperones that play key roles in establishing and maintaining chromatin structure. We report here the crystal structure of human RbAp46 bound to histone H4. RbAp46 folds into a seven-bladed beta propeller structure and binds histone H4 in a groove formed between an N-terminal alpha helix and an extended loop inserted into blade six. Surprisingly, histone H4 adopts a different conformation when interacting with RbAp46 than it does in either the nucleosome or in the complex with ASF1, another histone chaperone. Our structural and biochemical results suggest that when a histone H3/H4 dimer (or tetramer) binds to RbAp46 or RbAp48, helix 1 of histone H4 unfolds to interact with the histone chaperone. We discuss the implications of our findings for the assembly and function of RbAp46 and RbAp48 complexes.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas Nucleares
/
Histonas
/
Proteínas de Transporte
/
Chaperonas Moleculares
Tipo de estudo:
Prognostic_studies
Limite:
Humans
Idioma:
En
Revista:
Structure
Assunto da revista:
BIOLOGIA MOLECULAR
/
BIOQUIMICA
/
BIOTECNOLOGIA
Ano de publicação:
2008
Tipo de documento:
Article
País de afiliação:
Reino Unido