Molecular Mechanism of pH Regulation of TRPV1 Activation

pH调节TRPV1激活的分子机制

• 批准号: 8238102
• 负责人: JIE ZHENG
• 金额: $ 32.55万
• 依托单位: UNIVERSITY OF CALIFORNIA AT DAVIS
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-30 至 2016-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8238102
• 关键词: Address; Adopted; Affect; Afferent Neurons; Agonist; Binding; Binding Sites; Capsaicin; Chemicals; Clinical; Coupling; Development; Dose; E600; Environment; Fluorescence; Fluorescence Resonance Energy Transfer; Fluorometry; Goals; Heating; Indium; Inflammation; Intervention; Investigation; Ion Channel; Ischemia; Kinetics; Knowledge; Ligands; Light; Measurement; Mediating; Methods; Molecular; Movement; Nature; Neurons; Optics; Pain; Pathway interactions; Phosphatidylinositol 4,5-Diphosphate; Physiological; Physiology; Play; Predisposition; Process; Proteins; Regulation; Relative (related person); Research; Role; Site; Stimulus; Structure; TRPV1 gene; Temperature; Testing; Thermodynamics; Tissues; base; design; extracellular; fluorophore; protonation; receptor; research study; response; sensor; tool; voltage

DESCRIPTION (provided by applicant): The heat sensor TRPV1 channel is a polymodal receptor that plays a key role in mediating neuronal pain caused by various noxious stimuli. One such stimulus is extracellular acidification caused by inflammation, tissue damage and ischemia. Low pH is thought to activate TRPV1 both directly by serving as a channel activator and indirectly by potentiating the channel's response to other stimuli. How TRPV1 activation is controlled by pH as well as its relation to activation by heat, ligands, and endogenous channel modulators remains largely unknown. Importantly, the highly unique susceptibility of TRPV1 activity to a variety of physical and chemical factors makes the channel an attractive target for clinical intervention of pain. The overarching goal of our research is to understand the cellular sensing function of TRPV1 by elucidating molecular mechanisms underlying its polymodal activation by heat, capsaicin and other stimuli. In the proposed study we aim to reveal the structural and mechanistic nature of extracellular H+ regulation of TRPV1. As H+-induced TRPV1 activity has heat-dependent and agonist-dependent components, this investigation will also shed light on how heat and agonist control TRPV1 activity. We approach our goal through a combination of optical, electrophysiological, and molecular methods. In particular, we will apply a patch fluorometry approach to directly observe structural changes in the channel protein or the binding of regulatory molecules, using fluorophores as molecular sensors. Simultaneous fluorescent and electrical recordings permit direct correlation of structural changes to their effects on channel activation. Using these methods, we will address questions on how changes in pH, temperature, and the concentration of agonists are sensed by TRPV1, what channel structures convey these stimuli, and how these stimuli converge to control TRPV1 activation. Answers to these questions should directly benefit the development of new clinical tools for treating TRPV1- mediated neuronal pain. PUBLIC HEALTH RELEVANCE: TRPV1 serves as a key molecular element in mediating low pH-induced neuronal pain due to inflammation, tissue damage and ischemia. Our research aims at understanding how TRPV1 activation is controlled by extracellular acidification and its relationship with heat- and agonist-induced channel activation, which will shed light on designing potential clinical intervention of pain.

描述（由申请人提供）：热传感器TRPV1通道是一种多座受体，在介导由各种有害刺激引起的神经元疼痛中起关键作用。一种这样的刺激是由炎症，组织损伤和缺血引起的细胞外酸化。人们认为低pH值可以通过充当通道激活剂并间接地通过增强通道对其他刺激的响应来直接激活TRPV1。 TRPV1激活如何受到pH的控制，以及与热，配体和内源通道调节剂与激活的关系。重要的是，TRPV1活性对各种物理和化学因子的高度独特的敏感性使该通道成为疼痛临床干预的有吸引力的目标。我们研究的总体目标是通过阐明通过热，辣椒素和其他刺激来阐明其多聚座激活的分子机制，了解TRPV1的细胞感应功能。在拟议的研究中，我们旨在揭示TRPV1细胞外H+调节的结构和机械性质。由于H+诱导的TRPV1活性具有热依赖性和激动剂依赖性的成分，因此该研究还将阐明热和激动剂控制TRPV1活性。我们通过光学，电生理和分子方法的结合来实现我们的目标。特别是，我们将采用斑块荧光测定法直接观察通道蛋白中的结构变化或使用荧光团作为分子传感器的调节分子的结合。同时荧光和电记录允许结构变化与它们对通道激活的影响直接相关。使用这些方法，我们将解决有关pH，温度和激动剂浓度如何通过TRPV1感测，哪些通道结构传达这些刺激以及这些刺激如何收敛以控制TRPV1激活的问题。这些问题的答案应直接受益于用于治疗TRPV1介导的神经元疼痛的新临床工具的开发。 公共卫生相关性：TRPV1是介导炎症，组织损伤和缺血引起的低pH诱导神经元疼痛的关键分子元素。我们的研究旨在了解如何通过细胞外酸化及其与热和激动剂诱导的通道激活的关系来控制TRPV1激活，这将阐明设计潜在的疼痛临床干预。