STRUCTURE AND MECHANISM OF A POLYMODAL TRP ION CHANNEL

多模态TRP离子通道的结构和机制瞬时受体电位（TRP）离子通道对于感觉传导和细胞信号传导至关重要，并且TRP通道功能障碍与大量遗传性和获得性疾病相关，包括癌症、慢性疼痛、高血压和神经系统疾病。由于其在生理学和病理生理学中的中心作用，TRP通道已被深入研究，并且是最积极追求的药物靶标之一。然而，我们对TRP通道功能的理解和治疗干预的进展 由于缺乏大多数TRP通道的三维高分辨率结构信息而受阻。我们的长期目标是发展结构和生物化学的方法来阐明TRP通道在原子水平上的分子机制。通过开发新的方法来系统地评估TRP通道同源物的异源表达、纯化和优化，我们最近结晶了一个几乎全长的功能通道，并获得了初步的X射线衍射，分辨率为4.8 nm。随着这一技术突破和进一步优化，我们现在能够结合联合收割机X射线晶体学，单粒子冷冻电子显微镜（cryo-EM），膜片钳电生理学和定点诱变来解决基本的分子机制。具体来说，我们的目标是确定与激动剂或拮抗剂结合的通道的高分辨率X射线和冷冻电镜结构，以及与 调节通道活性的膜脂质，并剖析疾病相关突变的潜在机制。我们的工作将提供TRP通道在多个功能状态下的X射线和冷冻电镜结构，并揭示结构和分子机制。在这样做的过程中，我们不仅将带来对TRP通道功能的基本见解，而且还为合理设计用于治疗许多通道相关疾病的新疗法奠定了基础。

Structure and Mechanism of a Polymodal TRP Ion Channel Transient receptor potential (TRP) ion channels are crucial for sensory transduction and cellular signaling, and TRP channel dysfunction is associated with a vast array of hereditary and acquired diseases including cancer, chronic pain, hypertension, and neurological disorders. Because of their central roles in physiology and pathophysiology, TRP channels have been intensively studied and are among the most aggressively pursued drug targets. However, advances in our understanding of TRP channel function and therapeutic interventions have been hindered by a lack of three-dimensional high-resolution structural information for most TRP channels. Our long-term goal is to develop structural and biochemical approaches to elucidate molecular mechanisms of TRP channels at the atomic level. By developing new methods to systematically evaluate heterologous expression, purification, and optimization of TRP channel homologs, we have recently crystallized a nearly full-length functional channel and obtained preliminary X-ray diffraction to 4.8 Å resolution. With this technical breakthrough and further optimization, we are now able to combine X-ray crystallography, single-particle cryo-electron microscopy (cryo-EM), patch-clamp electrophysiology, and site-directed mutagenesis to address fundamental molecular mechanisms. Specifically, we aim to determine high-resolution X-ray and cryo-EM structures of the channel bound with agonists or antagonists, and in complex with membrane lipids that regulate channel activity, and to dissect the underlying mechanisms of disease-associated mutations. Our proposed work will provide X-ray and cryo-EM structures of a TRP channel in multiple functional states and uncover structural and molecular mechanisms. In doing so, we will not only bring fundamental insights into TRP channel function, but also establish a foundation for rational design of new therapeutics for the treatment of many channel-associated diseases.