LARG/RhoA信号转导通路的新型小分子探针的核磁片段筛选与组装

项目名称： LARG/RhoA信号转导通路的新型小分子探针的核磁片段筛选与组装

项目编号： No.21273216

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 数理科学和化学

项目作者： 阮科

作者单位： 中国科学技术大学

项目金额： 78万元

中文摘要： 小G蛋白RhoA与肿瘤细胞的生长和迁移密切关联，其活化受到上游的鸟苷交换因子调控。靶标鸟苷交换因子/小G蛋白的信号转导通路的小分子化合物，已逐渐成为抗肿瘤迁移药物研究的新热点。本项目拟分别以RhoA的鸟苷交换因子LARG与其上游的Plexcin-B1蛋白复合物和下游的RhoA复合物为靶点，创建中国首个（批）高度自动化的核磁小分子药物片段筛选平台，筛选抑制蛋白-蛋白作用或者将二者复合物稳定在失活状态下的新型苗头化合物。创造性的运用转移残留偶极耦合和准接触位移等核磁新技术，测量多个苗头化合物的相对取向和距离，在结构的基础上设计拼装新型的蛋白-蛋白复合物体系的小分子探针，尝试解决基于片段的药物发现中弱结合的蛋白/配基结构解析困难的瓶颈问题。进一步深入研究这类小分子化合物的体外亲和力、活性和它对肿瘤细胞迁移行为的影响，以此为小分子探针，阐明肿瘤细胞迁移的分子作用机制。

中文关键词： 蛋白-蛋白相互作用；核磁共振波谱学；基于片段的先导化合物发现；蛋白-配基相互作用；分子识别

英文摘要： Small GTPase RhoA is cycled from the inactive GDP bound conformation to the active GTP bound conformation, activated by its guanine nucleotide exchange factors (GEFs), to trigger the downstream cascade, while the deregulation of this signal transduction pathway would lead to the uncontrolled tumor cell growth and migration. Recently, the discovery of small molecules to regulate such GEF/RhoA pathway has attracted much interests, especially the compounds to block the protein-protein interactions or to trap the complex in their inactive conformation. We plan to setup the first highly automated NMR fragment based screening facility in China, initially targeting the complexes of Leukemia Associated Rho Guanine nucleotide exchange factor (LARG) and its upstream Plexin-B1 and downstream RhoA, respectively. Novel NMR techniques, e.g., Residual Dipolar Couplings and PseudoContact Shifts, will be deployed to retrieve the valuable structural information of the distance and orientations between target proteins and the fragment hits, which provides a harw eyed view of the follow-up fragment assembling to novel potent ligands. The success of our research would make a breakthrough in solving the weak interaction between protein and fragment hits by conventional NMR/X-ray methods in fragment based lead discovery. Our resea

英文关键词： Protein-protein interaction；NMR spectroscopy；Fragment-based lead discovery；Protein-ligand interaction；Molecular recognition