NMR structure of peptide and protein complexes

描述(申请人提供)：这项研究的主要目标是从结构和动力学方面增加我们对细胞信号转导中调节蛋白质功能的分子机制的理解。信号通路包括许多蛋白质-蛋白质相互作用，而单个蛋白质通常以多种关联方式发挥作用。相应地，构象柔性在蛋白质-蛋白质结合的分子识别事件和控制蛋白酪氨酸激酶的激活中起着重要的作用。在这个项目中，我们将使用核磁共振和计算方法来研究构象平衡对于识别Syk和Src家族的激酶，以及对Src激酶的构象激活非常重要。SYK和Src家族蛋白酪氨酸激酶在B细胞信号转导中起重要作用。Src家族和Syk家族都与多种疾病状态有关，特别是与细胞转化有关。对这些蛋白质的分子识别的详细了解对于设计针对这些疾病的抑制剂和潜在的治疗剂是重要的。核磁共振实验和分子动力学计算相结合的方法将用于确定各种SH2复合体的结构，并获得与结合和Src激活相关的蛋白质运动信息。我们试图了解：非结合态的构象柔性如何在决定结合中起作用；与Syk的结构域区域结合引起的大的构象变化是否对识别Syk的这个多功能位点具有普遍意义；柔性配体的SH2结合中的熵/热补偿是什么；以及分子内结构域接触如何影响Src的构象激活。

DESCRIPTION (provided by applicant): The major goal of this study is to increase our understanding, in terms of structure and dynamics, of the molecular mechanisms that regulate protein function in cellular signal transduction. Signaling pathways comprise numerous protein-protein interactions, and an individual protein often functions in multiple associations. Correspondingly, conformational flexibility plays an important role in molecular recognition events of protein-protein association and in the control of protein tyrosine kinase activation. NMR and computational methods will be used in this project to investigate conformational equilibrium important for recognition of Syk and Src-family kinases, and for conformational activation of Src kinase. Syk and Src-family protein tyrosine kinases are essential in B-cell signaling. Both Src family kinases and Syk family kinases are associated with several disease states and in particular with cell transformation. Detailed understanding of molecular recognition of these proteins is important for designing inhibitors and potential therapeutic agents against these diseases. A combination of NMR experiment and molecular dynamics computation will be used to determine the structure of various SH2 complexes and obtain information on protein motion related to binding and Src activation. We seek to understand: how conformational flexibility in the unbound state plays a role in determining binding; whether the large conformational change induced by binding to an interdomain region of Syk is general to recognition of this multifunctional site of Syk; what underlies entropy/enthalpy compensation in SH2 binding of flexible ligands; and how intramolecular domain contacts effect Src conformational activation.