P2X受体各亚型之间门控机制的差异与新型分子发现

P2X receptors are extracellular ATP-activated membrane cation ion channels involved in signal transition, cardiovascular modulation, immunoregulatory, pain perception, cognition, and so on. In the past twenty years, P2X receptors received widespread attentions for their potential roles as new and ideal drug targets and some small molecules targeting P2X receptors have entered into clinical trials. Various subtypes of P2X receptors were identified sequentially. These distinct subtypes are similar in evolutionary origin but not in functions. The discovery of subtype-specific small molecules is one of the difficulty and hot spots in this field. These new discoveried subtype-specific small molecules will greatly propomt the basic researches as well as new the drug design of P2X receptors. Here, the applicants intend to study the subtle differences among gating mechanisms of various subtypes of P2X receptors via interdisciplinary methodological approaches, including electrophysiological recording, covalent modification, mutagenesis, molecular dynamics simulations, etc. Based on the identified subtle differences in gating mechanism, the applicant further intended to find novel small molecules specifically acting on one of subtypes of P2X1, 2, 3, 4 and 7 receptors. The applicant also planned to study physiological and pharmacological functions of those new identified small molecules via electrophysiological recording and behavioral approaches. This project is expected to contribute to advance our molecular understanding of the complex gating mechanism of various subtypes of P2X receptors, and will help to discover novel leading compounds for P2X receptors. This project will also provide a basis for further health interventions.

P2X受体是细胞膜上可感受胞外ATP，参与心血管、免疫、炎症、痛觉、认知等重要生物学功能的非选择性阳离子通道。近年来，P2X受体作为新型的药物设计靶点而备受关注，已有多个化合物进入临床试验阶段。目前，P2X受体已发现多种亚型，介导相同或不同的生物学功能。诠释各亚型的门控机制与发现各亚型分别特异的活性分子是本领域亟待解决的热点和难点问题；这类分子的发现有望为本领域的基础研究和药物研发带来积极的推动作用。本课题拟采用膜片钳电生理、共价修饰、基因突变，结合计算生物学等多学科交叉方法研究P2X受体各亚型之间门控机制的细微差异。并以各亚型间门控的差异为切入点，通过基于结构的分子发现和药物设计手段，结合实验筛选去发现P2X1,2,3,4,7等重要亚型分别特异的活性小分子。最终通过膜片钳电生理、行为学等手段深入探讨其功能，以期为P2X受体相关疾病的新型药物发现提供新的结构基础和先导结构。

P2X受体是细胞膜上可感受胞外ATP的非选择性阳离子通道。因其参与了心血管、免疫、炎症、痛觉、认知等众多重要的生理病理过程，近年来，P2X受体作为新型的药物设计靶点而备受关注，已有多个化合物进入临床试验阶段。P2X受体存在多种亚型，介导相同或不同的生物学功能。本课题主要研究P2X受体各亚型之间门控共同机制和细微差异，并寻找特异性活性小分子。通过膜片钳电生理、共价修饰、基因突变，结合计算生物学等多学科交叉方法，确定了P2X受体的左鳍和背鳍的相对运动是门控过程中的必不可少的变构行为；发现了保守盐桥R309-D85对维持P2X通道功能的重要作用，且因为周围氨基酸不同而具备亚型差异性；发现了生理浓度的Ca2+,Mg2+对饱和ATP诱导的P2X受体激活产生的抑制作用；发现多个特异性活性小分子，确定了NF110等小分子对于P2X受体的种属特异性以及机制。为P2X受体相关疾病的新型药物发现提供了新的结构基础和先导结构。