固有无序蛋白相互作用的动力学网络和机理研究

固有无序蛋白（IDP）是人类蛋白质组中占比超过40%的无固定三维结构蛋白。近年的研究发现IDP相关的蛋白-蛋白相互作用在很多生命过程中扮演重要角色。由于缺乏固定结构，也不具有构象均一性，我们无法用传统的结构生物学方法去研究IDP的“结构-功能”关系。在前期工作中，我们结合实验和计算模拟研究，发现了IDP之间可以通过动态多位点相互作用形成无序的“极端模糊复合物”。在本项目中，我们在前期工作的基础上，针对IDP的两种相互作用模式（“耦合折叠-结合”和“动态多位点相互作用”）提出运用分子动力学模拟和马尔科夫态模型方法构建IDP相互作用过程的动力学网络，剖析结合过程中的关键构象状态和关键途径，阐释以上两类相互作用的微观机制。同时，通过设计突变，结合核磁共振和单分子荧光共振能量转移等实验方法检验计算模拟中得出的机理模型。

Intrinsically disordered proteins (IDPs) do not fold into stable 3-D structures. In human genome, about 40% protein coded genes contain intrinsically disorderd protein regions. Recent studies show that IDP related protein-protein interactions play important roles in many physiological processes. Due to the lack of folded structure and the lack of conformational homogeneity, IDPs could not be studied in the frame of “structure-function relationship” using conventional structural biology techniques. In our previous work, we discovered that two IDPs can form extremely disordered complex through dynamic multisite interactions by combined use of experimental and computational methods. In this project, we proposed to study two binding modes of IDP (coupled folding and binding and dynamic multisite interaction). We will mainly use MD simulation and Markov state model analysis to construct the kinetic nectwork of IDP interaction, and analyze the key states and pathways during the binding process to elucidate the mechanism. Meanwhile, we will also design mutations based on the simulation results and perform NMR and smFRET measurements to validate the binding mechanisms.