An Interaction between DNA Polymerase and Helicase Is Essential for the High Processivity of the Bacteriophage T7 Replisome
An Interaction between DNA Polymerase and Helicase Is Essential for the High Processivity of the Bacteriophage T7 Replisome
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DOI：
10.1074/jbc.m112.410647
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发表时间：
2012-11-09
影响因子：
4.8
通讯作者：
Richardson, Charles C.
中科院分区：
文献类型：
--
作者：
Kulczyk, Arkadiusz W.;Akabayov, Barak;Richardson, Charles C.
前导DNA链的合成需要DNA聚合酶和DNA解旋酶的协调活性，而滞后链的合成涉及这些蛋白质与DNA引发酶的相互作用。我们提出了第一个结构模型的噬菌体T7 DNA解旋酶-DNA聚合酶复合物使用的小角X射线散射，单分子和生物化学方法的组合。我们建议，蛋白质-蛋白质界面稳定的前导链的合成涉及两个不同的相互作用：一个稳定的结合的解旋酶的棕榈域的聚合酶和静电结合的羧基末端尾的解旋酶的聚合酶上的基本补丁。DNA引发酶促进DNA解旋酶与ssDNA的结合，并通过稳定DNA解旋酶而有助于DNA解旋酶-DNA聚合酶复合物的形成。
Synthesis of the leading DNA strand requires the coordinated activity of DNA polymerase and DNA helicase, whereas synthesis of the lagging strand involves interactions of these proteins with DNA primase. We present the first structural model of a bacteriophage T7 DNA helicase-DNA polymerase complex using a combination of small angle x-ray scattering, single-molecule, and biochemical methods. We propose that the protein-protein interface stabilizing the leading strand synthesis involves two distinct interactions: a stable binding of the helicase to the palm domain of the polymerase and an electrostatic binding of the carboxyl-terminal tail of the helicase to a basic patch on the polymerase. DNA primase facilitates binding of DNA helicase to ssDNA and contributes to formation of the DNA helicase-DNA polymerase complex by stabilizing DNA helicase.