Functional Dynamics in Replication Protein A DNA Binding and Protein Recruitment Domains
Functional Dynamics in Replication Protein A DNA Binding and Protein Recruitment Domains
复制标题
DOI：
10.1016/j.str.2015.04.008
复制
发表时间：
2015-06-02
期刊：
影响因子：
5.7
通讯作者：
Chazin, Walter J.
中科院分区：
文献类型：
--
作者：
Brosey, Chris A.;Soss, Sarah E.;Chazin, Walter J.
复制蛋白A（RPA）是许多DNA加工机器的重要支架;其功能依赖于其模块化结构。在这里，我们报告15 N-核磁共振异相弛豫分析，以表征运动的单链（SS）DNA结合和蛋白质相互作用模块中的RPA 70亚基。我们的研究结果提供了直接的证据，协调的运动串联RPA 70 AB ssDNA结合结构域。此外，发现ssDNA底物的结合会导致急剧的重新取向和结构域间运动的完全耦合。相反，RPA 70 N蛋白相互作用结构域在结构上和动力学上保持独立于RPA 70 AB，而不管ssDNA的结合。70 N和70 AB模块之间的这种自主运动支持这样一种模型，即RPA的两种结合功能完全独立地介导，但根据其柔性系链的长度保持差异协调。提出了一个关键的作用，在确定RPA的功能动力学的球状域之间的连接器。
Replication Protein A (RPA) is an essential scaffold for many DNA processing machines; its function relies on its modular architecture. Here, we report 15 N-nuclear magnetic resonance heteronuclear relaxation analysis to characterize the movements of single-stranded (ss) DNA binding and protein interaction modules in the RPA70 subunit. Our results provide direct evidence for coordination of the motion of the tandem RPA70AB ssDNA binding domains. Moreover, binding of ssDNA substrate is found to cause dramatic reorientation and full coupling of inter-domain motion. In contrast, the RPA70N protein interaction domain remains structurally and dynamically independent of RPA70AB regardless of binding of ssDNA. This autonomy of motion between the 70N and 70AB modules supports a model in which the two binding functions of RPA are mediated fully independently, but remain differentially coordinated depending on the length of their flexible tethers. A critical role for linkers between the globular domains in determining the functional dynamics of RPA is proposed.