Organization of the archaeal MCM complex on DNA and implications for the helicase mechanism.
Nat Struct Mol Biol
; 12(9): 756-62, 2005 Sep.
Article
em En
| MEDLINE
| ID: mdl-16116441
ABSTRACT
The homomultimeric archaeal mini-chromosome maintenance (MCM) complex serves as a simple model for the analogous heterohexameric eukaryotic complex. Here we investigate the organization and orientation of the MCM complex of the hyperthermophilic archaeon Sulfolobus solfataricus (Sso) on model DNA substrates. Sso MCM binds as a hexamer and slides on the end of a 3'-extended single-stranded DNA tail of a Y-shaped substrate; binding is oriented so that the motor domain of the protein faces duplex DNA. Two candidate beta-hairpin motifs within the MCM monomer have partially redundant roles in DNA binding. Notably, however, conserved basic residues within these motifs have nonequivalent roles in the helicase activity of MCM. On the basis of these findings, we propose a model for the mechanism of the helicase activity of MCM and note parallels with SV40 T antigen.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
DNA
/
Proteínas Nucleares
/
DNA Helicases
/
Proteínas Arqueais
/
Proteínas de Ligação a DNA
Tipo de estudo:
Prognostic_studies
Limite:
Humans
Idioma:
En
Revista:
Nat Struct Mol Biol
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2005
Tipo de documento:
Article
País de afiliação:
Reino Unido