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Intersubunit allosteric communication mediated by a conserved loop in the MCM helicase.

ABSTRACT: The minichromosome maintenance (MCM) helicase is the presumptive replicative helicase in archaea and eukaryotes. The archaeal homomultimeric MCM has a two-tier structure. One tier contains the AAA+ motor domains of the proteins, and these are the minimal functional helicase domains. The second tier is formed by the N-terminal domains. These domains are not essential for MCM helicase activity but act to enhance the processivity of the helicase. We reveal that a conserved loop facilitates communication between processivity and motor tiers. Interestingly, this allostery seems to be mediated by interactions between, rather than within, individual protomers in the MCM ring.

SUBMITTER: Barry ER

PROVIDER: S-EPMC2633543 | biostudies-literature | 2009 Jan

REPOSITORIES: biostudies-literature

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Intersubunit allosteric communication mediated by a conserved loop in the MCM helicase.

Barry Elizabeth R ER Lovett Janet E JE Costa Alessandro A Lea Susan M SM Bell Stephen D SD

Proceedings of the National Academy of Sciences of the United States of America 20090121 4

The minichromosome maintenance (MCM) helicase is the presumptive replicative helicase in archaea and eukaryotes. The archaeal homomultimeric MCM has a two-tier structure. One tier contains the AAA+ motor domains of the proteins, and these are the minimal functional helicase domains. The second tier is formed by the N-terminal domains. These domains are not essential for MCM helicase activity but act to enhance the processivity of the helicase. We reveal that a conserved loop facilitates communic ...[more]

PMID: 19164574

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