Structural Basis for the Unique Multivalent Readout of Unmodified H3 Tail by Arabidopsis ORC1b BAH-PHD Cassette.
Structural Basis for the Unique Multivalent Readout of Unmodified H3 Tail by Arabidopsis ORC1b BAH-PHD Cassette.
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DOI：
10.1016/j.str.2016.01.004
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发表时间：
2016-03-01
期刊：
影响因子：
--
通讯作者：
Du J
中科院分区：
文献类型：
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作者：
Li S;Yang Z;Du X;Liu R;Wilkinson AW;Gozani O;Jacobsen SE;Patel DJ;Du J
DNA复制的启动依赖于起源识别复合体(ORC)的形成。植物ORC亚单位1(ORC1)蛋白具有一个保守的BAH结构域，其功能可能受表观遗传机制的调控。在这里，我们报告了对拟南芥ORC1b BAH-PhD盒的结构和生化研究，该盒专门识别未经修饰的H3尾巴。ORC1b BAH-PHD盒与H3(1-15)肽形成的复合体的晶体结构揭示了对H3尾部R2、T3和K4未修饰状态的严格要求，以及用于识别H3肽的一种新的多价BAH和PHD读出模式。这种认识可能有助于表观遗传调控DNA复制的启动。
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.