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Hexameric ring structure of human MCM10 DNA replication factor.

ABSTRACT: The DNA replication factor minichromosome maintenance 10 (MCM10) is a conserved, abundant nuclear protein crucial for origin firing. During the transition from pre-replicative complexes to pre-initiation complexes, MCM10 recruitment to replication origins is required to provide a physical link between the MCM2-7 complex DNA helicase and DNA polymerases. Here, we report the molecular structure of human MCM10 as determined by electron microscopy and single-particle analysis. The MCM10 molecule is a ring-shaped hexamer with large central and smaller lateral channels and a system of inner chambers. This structure, together with biochemical data, suggests that this important protein uses its architecture to provide a docking module for assembly of the molecular machinery required for eukaryotic DNA replication.

SUBMITTER: Okorokov AL

PROVIDER: S-EPMC2002553 | biostudies-literature | 2007 Oct

REPOSITORIES: biostudies-literature

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Hexameric ring structure of human MCM10 DNA replication factor.

Okorokov Andrei L AL Waugh Alastair A Hodgkinson Julie J Murthy Andal A Hong Hye Kyung HK Leo Elisabetta E Sherman Michael B MB Stoeber Kai K Orlova Elena V EV Williams Gareth H GH

EMBO reports 20070907 10

The DNA replication factor minichromosome maintenance 10 (MCM10) is a conserved, abundant nuclear protein crucial for origin firing. During the transition from pre-replicative complexes to pre-initiation complexes, MCM10 recruitment to replication origins is required to provide a physical link between the MCM2-7 complex DNA helicase and DNA polymerases. Here, we report the molecular structure of human MCM10 as determined by electron microscopy and single-particle analysis. The MCM10 molecule is ...[more]

PMID: 17823614

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