THE INHIBITION OF GRIP1/HTR INTERACTIONS

这个子项目是利用由NIH/NCRR资助的中心拨款提供的资源的许多研究子项目之一。子项目和调查员(PI)可能从另一个NIH来源获得了主要资金，因此可能会出现在其他CRISE条目中。列出的机构是针对中心的，而不一定是针对调查员的机构。我们这个项目的总体目标是建立阻止蛋白质与有机小分子相互作用的方法。这类抑制剂可以选择性地阻止特定复合体的组装，从而扰乱下游过程。通常，这种复杂的形成是由模块化的蛋白质结合模块介导的，如WW、PDZ和SH3基序。最近，一些结构研究揭示了一类新的蛋白质相互作用。这种结合模式包括将一种蛋白质的一个小螺旋片段的一个面装配到另一个明确定义的裂隙中。一个例子是糖皮质激素受体相互作用蛋白1(GRIP1)与人甲状腺激素受体β1(HTR=DF1)配体(T3)复合体的结合。由于螺旋的总结合部位相当小，并且两个伙伴之间没有主干氢键，这种类型的相互作用代表了一种有希望的蛋白质-蛋白质结合的小分子抑制剂的测试案例。该项目的长期研究目标是开发一种可用于GRIP1/hTRb1/T3结合的细胞通透性抑制剂，具体而言，(1)开发一种适用于高通量筛选GRIP1与HTR=DF1/T-3复合体结合的竞争性抑制剂的可靠的生化分析方法；(2)合成一种跨越GRIP1可能结合部分的构象受限的α-螺旋肽，并将该模板作为抑制剂进行测试；(3)探索GRIP1螺旋与HTR=DF1/T-3复合体结合的最低结构限制条件；以及(4)开始使用肽模型定义GRIP1螺旋的构效关系。计算机图形实验室的资源正被用于分析配体和受体之间的相互作用，并在此分析的基础上设计潜在的抑制剂。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Our overall goal for this project is to establish methods for blocking protein-protein interactions with small organic molecules. Such inhibitors could selectively prevent the assembly of particular complexes and thus disrupt downstream processes. Often such complex formations are mediated by modular protein binding modules such as the WW, PDZ, and SH3 motifs. Recently, several structural studies have revealed a new class of protein interaction. This binding mode involves the fitting of one face of a small helical segment of one protein into a well-defined cleft on the other. One example is the binding of glucocorticoid receptor-interacting protein 1 (GRIP1) to the human thyroid hormone receptor beta 1 (hTR=DF1) ligand (T3) complex. Due to the rather small size of the overall binding site for the helix and the absence of backbone hydrogen bonding between the two partners, this type of interaction represents a promising test case for small molecule inhibitors of protein-protein binding. The long term research goal of the project is to develop a cell permeable inhibitor for GRIP1/hTRb1/T3 binding, specifically (1) to develop a robust biochemical assay suitable for high throughput screening for competitive inhibitors of the binding of GRIP1 to hTR=DF1/T-3 complex; (2) to synthesize a conformationally constrained a-helical peptide that spans the putative binding portion of GRIP1 and test this template as an inhibitor; (3) to explore the minimal structural constraints for the binding of the GRIP1 helix to the hTR=DF1/T-3 complex; and, (4) to begin to define the structure-activity relationship for the GRIP1 helix using peptide models. The Computer Graphics Laboratory's resources are being utilized to analyze the interaction between ligand and receptor and to design potential inhibitors based upon this analysis.