Structural insight into TRPA1 channel interactionwith agonist and antagonist

描述（由申请人提供）：TRPA 1是一种Ca 2+渗透性、非选择性阳离子通道，是哺乳动物中的关键疼痛感受器之一。它已成为镇痛药和抗炎药的新靶点。由TRPA 1介导的疼痛感觉涉及巯基反应性化合物和炎症介质对通道上的N-末端半胱氨酸残基的修饰。巯基反应性化合物在静息状态下与通道结合导致通道激活，随后迅速脱敏。虽然通道活性已被广泛研究的电生理方法，很少有人知道的结构机制的通道激活和脱敏。此外，两种直接抑制TRPA 1的化合物正在进行临床前试验，了解这些化合物抑制TRPA 1的机制对于推进我们对功能相关TRPA 1构象之间结构差异的认识将是重要的。使用冷冻电镜，定点诱变，有限的蛋白水解，和质谱，在这项授权，我们的目标是建立一个详细的结构， 了解TRPA 1通道的激活、脱敏和抑制机制，有助于合理设计新型镇痛药物。

DESCRIPTION (provided by applicant): TRPA1 is a Ca2+-permeable, non-selective cation channel and one of the key pain sensors in mammals. It has emerged as a novel target for analgesics and anti-inflammatory agents. Pain sensation mediated by TRPA1 involves modification of N-terminal cysteine residues on the channel by thiol-reactive compounds and inflammatory mediators. Binding of thiol-reactive compounds to the channel in the resting state leads to channel activation followed rapidly by desensitization. While channel activity has been studied extensively by electrophysiological methods, little is known about the structural mechanisms of channel activation and desensitization. Additionally, two compounds that directly inhibit TRPA1 are in pre-clinical trials, and understanding the mechanism of TRPA1 inhibition by these compounds will be important for advancing our knowledge of the structural differences between functionally relevant TRPA1 conformations. Using cryo-EM, site-directed mutagenesis, limited proteolysis, and mass spectrometry, in this grant we aim to establish a detailed structural understanding of the mechanisms of TRPA1 channel activation, desensitization and inhibition, which will help facilitate rational design of novel analgesics.