Structural insight into TRPA1 channel interactionwith agonist and antagonist

描述（由申请人提供）：TRPA1是一种Ca2+可渗透的非选择性阳离子通道，是哺乳动物的关键疼痛传感器之一。它已成为止痛剂和抗炎剂的新靶点。TRPA1介导的痛觉涉及巯基反应性化合物和炎症介质对通道上n端半胱氨酸残基的修饰。在静息状态下，巯基活性化合物与通道结合导致通道激活，随后迅速脱敏。虽然电生理学方法对通道活性进行了广泛的研究，但对通道激活和脱敏的结构机制知之甚少。此外，两种直接抑制TRPA1的化合物正在进行临床前试验，了解这些化合物抑制TRPA1的机制对于提高我们对功能相关TRPA1构象之间结构差异的认识非常重要。利用低温电镜、定点诱变、有限蛋白水解和质谱，我们的目标是建立一个详细的结构

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.