Structural dynamics underlying GPCR-G protein selectivity

GPCR-G 蛋白选择性的结构动力学

基本信息

批准号：
10559695
负责人：
Nagarajan Vaidehi
金额：
$ 35.2万
依托单位：
BECKMAN RESEARCH INSTITUTE/CITY OF HOPE
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-05-17 至 2025-01-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10559695
关键词：
Affect Agonist Angiotensin Receptor Binding Binding Sites Biological Assay Biological Process Cells Code Collaborations Communication Complex Computing Methodologies Coupled Coupling Diabetes Mellitus Drug Targeting Engineering Exhibits Explosion Fluorescence Resonance Energy Transfer Funding G alpha q Protein G-Protein Signaling Pathway G-Protein-Coupled Receptors GTP-Binding Proteins Goals Grant Interdisciplinary Study Knowledge Ligand Binding Ligands Malignant Neoplasms Measurement Measures Mediating Methods Modeling Molecular Conformation Outcome Pathway interactions Pharmaceutical Preparations Process Protein Dynamics Research Proposals Resolution Role Shapes Signal Pathway Site Structure Techniques Testing Therapeutic Tissues Universities Variant Work design drug discovery experimental study extracellular hypertension treatment insight molecular dynamics molecular scale protein complex receptor sensor side effect spectroscopic survey structural determinants three dimensional structure tool

项目摘要

Summary: Title: Structural dynamics underlying GPCR-G protein selectivity Upon binding to agonists with different efficacies, G protein-coupled receptors (GPCRs) mediate multiple signaling pathways by coupling to different subtypes of G proteins. Certain agonists exhibit selectivity in their efficacy to specific G-protein signaling pathways. Such ligands provide precise therapeutic benefits with fewer side effects as drugs compared to today's GPCR-targeted drugs. There are very few selective ligands known for specific G-protein signaling pathways because designing such agonists is a daunting experimental challenge. This is due to serious lack of understanding of how GPCRs modulate their functional selectivity for their cognate G-protein when bound to different type of agonists and in cells. In the past three years using a combination of multiscale molecular dynamics (MD) method and genetically coded FRET sensors we have shown that GPCRs have latent intracellular cavities that can reshape and couple to different G-proteins. By reengineering G-proteins and GPCRs we have identified the hotspot residues in the GPCR-G-protein interface that serve as the “QR code” for G-protein selective coupling by GPCRs. Although it is clear that allosteric communication from the ligand binding site to the G-protein coupling site plays a role in G-protein selectivity very little is known about the mechanism of this communication and the residues involved in this process. Here we propose to (1) use the computational method Allosteer developed in our lab in combination with FRET sensors, NanoBRET assays and cell based downstream assays to delineate the allosteric network of GPCR residues involved in regulating G-protein selectivity in 9 different Gs, Gi and Gq coupled class A GPCRs in cellular conditions. The second aim is to understand the effect of partial agonists in comparison to the full agonists, on the GPCR-G-protein selective coupling. We will identify the hotspot residues on the G-protein and GPCRs when bound to partial agonists and compare the similarities and differences with full agonists. The outcome of the proposed work will provide the role of allosteric network of residues in G-protein selectivity and how partial agonists modulate the receptor conformations. This will push forward our understanding of the biological process of how GPCRs recognize their cognate G-proteins in live cells.

概括：标题：GPCR-G 蛋白选择性的结构动力学 G 蛋白偶联受体 (GPCR) 与不同功效的激动剂结合后，介导通过与不同的 G 蛋白亚型偶联而发挥多种信号传导途径。此类配体对特定 G 蛋白信号传导途径的功效具有选择性。与当今的 GPCR 靶向药物相比，作为药物具有更少的治疗益处和更少的副作用。已知用于特定 G 蛋白信号传导途径的选择性配体非常少，因为设计此类激动剂是一项艰巨的实验挑战，这是由于严重缺乏对其如何进行的了解。当与不同类型的 GPCR 结合时，GPCR 会调节其同源 G 蛋白的功能选择性。在过去的三年里，结合使用多尺度分子动力学。 (MD) 方法和基因编码的 FRET 传感器我们已经证明 GPCR 具有潜在的细胞内通过重新设计 G 蛋白和 GPCR，可以重塑空腔并与不同的 G 蛋白偶联。我们已经确定了 GPCR-G-蛋白界面中的热点残基，这些残基可作为“QR 码” GPCR 选择性偶联 G 蛋白，但很明显，变构通讯来自于 GPCR。配体与 G 蛋白偶联位点的结合位点在 G 蛋白选择性中发挥的作用目前知之甚少关于这种沟通的机制以及这个过程中涉及的残留物，我们在这里。建议（1）使用我们实验室开发的Allosteer计算方法结合FRET 传感器、NanoBRET 测定和基于细胞的下游测定来描绘变构网络 GPCR 残基参与调节 9 种不同的 Gs、Gi 和 Gq 偶联 A 类中的 G 蛋白选择性 GPCR 在细胞条件下的第二个目的是了解部分激动剂在细胞条件下的作用。与完全激动剂相比，我们将确定 GPCR-G 蛋白选择性偶联的热点。当与部分激动剂结合时，G 蛋白和 GPCR 上的残基并比较相似性和拟议工作的结果将提供变构的作用。 G 蛋白选择性中的残基网络以及部分激动剂如何调节受体这将推动我们对 GPCR 的生物学过程的理解。识别活细胞中的同源 G 蛋白。