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Structural Basis for the Unique Multivalent Readout of Unmodified H3 Tail by Arabidopsis ORC1b BAH-PHD Cassette.

ABSTRACT: DNA replication initiation relies on the formation of the origin recognition complex (ORC). The plant ORC subunit 1 (ORC1) protein possesses a conserved N-terminal BAH domain with an embedded plant-specific PHD finger, whose function may be potentially regulated by an epigenetic mechanism. Here, we report structural and biochemical studies on the Arabidopsis thaliana ORC1b BAH-PHD cassette which specifically recognizes the unmodified H3 tail. The crystal structure of ORC1b BAH-PHD cassette in complex with an H3(1-15) peptide reveals a strict requirement for the unmodified state of R2, T3, and K4 on the H3 tail and a novel multivalent BAH and PHD readout mode for H3 peptide recognition. Such recognition may contribute to epigenetic regulation of the initiation of DNA replication.

SUBMITTER: Li S

PROVIDER: S-EPMC4775424 | biostudies-literature | 2016 Mar

REPOSITORIES: biostudies-literature

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Structural Basis for the Unique Multivalent Readout of Unmodified H3 Tail by Arabidopsis ORC1b BAH-PHD Cassette.

Li Sisi S Yang Zhenlin Z Du Xuan X Liu Rui R Wilkinson Alex W AW Gozani Or O Jacobsen Steven E SE Patel Dinshaw J DJ Du Jiamu J

Structure (London, England : 1993) 20160211 3

DNA replication initiation relies on the formation of the origin recognition complex (ORC). The plant ORC subunit 1 (ORC1) protein possesses a conserved N-terminal BAH domain with an embedded plant-specific PHD finger, whose function may be potentially regulated by an epigenetic mechanism. Here, we report structural and biochemical studies on the Arabidopsis thaliana ORC1b BAH-PHD cassette which specifically recognizes the unmodified H3 tail. The crystal structure of ORC1b BAH-PHD cassette in co ...[more]

PMID: 26876097

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