Quantitative analysis of metabotropic glutamate receptor activation and modulation

项目摘要 G蛋白偶联受体（GPCRs）是人类最大的膜受体家族， 成为最大的药物靶点家族，市场上所有药物中有35%以上发挥作用 通过GPCR。尽管它们是可取的，但到目前为止，许多GPCR家庭仍然不坚固，部分原因是缺乏 关于它们的激活和调节的机械知识。代谢型谷氨酸受体（mGluRs） 是C类GPCR的成员，是谷氨酸信号传导的关键调节剂。由于其广泛的 它们在组织中的表达及其核心作用，是神经系统疾病最有前途的药物靶点之一。 例如脆性X综合征、癫痫、焦虑、精神分裂症以及某些癌症。进展 蛋白质工程和功能，结构和计算方法在过去的二十年里， 提供了对mGluRs的结构、信号传导和表达模式的见解。然而，一位将军 配体如何改变mGluRs的形状，以及这种构象变化如何通过 膜和超过12 nm激活特定的信号传导途径的机制知之甚少。在这项研究中，我们将 开发一种新的技术，使我们能够观察一个单一的mGluR蛋白，同时发挥作用， 在真实的时间里的生理条件。这将使我们能够量化不同领域的运动， 参与信号传导的受体。接下来，我们将采用这种方法来研究如何 合成 调制器 的 mGluR 信令 影响 蛋白 构象 和 动力学 到 胆固醇和 情感感受器 发信号。这是一个多学科的建议，其中最先进的体外单分子FRET（smFRET） 光谱学是由活细胞成像、蛋白质工程和生物物理和生物化学补充的 方法.一旦完成，拟议的研究可以为合理设计 副作用少的有效药物。此外，这些研究将提供一个总体路线图， 用于哺乳动物膜蛋白的定量高分辨率结构-功能研究。

Project Summary G protein-coupled receptors (GPCRs) are the largest family of membrane receptors in human and have emerged as the largest family of drug targets with more than 35% of all drugs on the market functioning through GPCRs. Despite their desirability, to date, many GPCR families remain undrugged, partly due to lack of mechanistic knowledge about their activation and modulation. Metabotropic glutamate receptors (mGluRs) are members of class C GPCRs and are critical modulators of glutamate signaling. Due to their widespread expression in tissue and their central role they are among the most promising drug targets for the neurological disorders such as fragile X syndrome, epilepsy, anxiety, schizophrenia as well as some cancers. Advances in protein engineering and functional, structural and computational methods in the past twenty years have provided insights into the architecture, signaling and expression patterns of mGluRs. However, a general model of how ligands change the shape of mGluRs and how this conformational change is relayed across the membrane and over 12 nm to activate specific signaling pathways is poorly understood. In this research we will develop a novel technology that will allow us to watch a single mGluR protein while functioning in physiological conditions, in real time. This will allow us to quantify the motions of different domains of the receptor that are involved in signaling. Next, we will employ this approach to study how synthetic modulators of mGluR signaling affect protein conformation and dynamics to cholesterol and affect receptor signaling. This is a multi-disciplinary proposal where state-of-the-art in vitro single-molecule FRET (smFRET) spectroscopy is complemented by live-cell imaging, protein engineering and biophysical and biochemical methods. Once accomplished, the proposed research could provide a critical step towards rational design of efficient drugs with fewer undesirable side effects. Furthermore, these studies will provide a general roadmap for quantitative high-resolution structure-function studies of mammalian membrane proteins.