Mechanisms of Disease associated with mechanically-activated Piezo ion channels

与机械激活压电离子通道相关的疾病机制

• 批准号: 10326400
• 负责人: Jorg Grandl
• 金额: $ 37.42万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-05-01 至 2025-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10326400
• 关键词: Affect; Arthrogryposis; Blood Vessels; Blood flow; Breathing; C-terminal; Cells; Colorectal; Cysteine; DNA Sequence Alteration; Detection; Diagnosis; Disease; Distal; Dysplasia; Electrophysiology (science); Engineering; Extracellular Domain; Frequencies; Goals; Gordon syndrome; Heart; Hemolytic Anemia; Human; Ion Channel; Ions; Kinetics; Knowledge; Ligands; Light; Lung; Lymphatic; Marden-Walker syndrome; Measures; Mechanics; Membrane; Microphthalmos; Molecular; Molecular Conformation; Mutation; Pathway interactions; Patients; Permeability; Physiological; Piezo 1 ion channel; Piezo 2 ion channel; Piezo ion channels; Point Mutation; Probability; Proprioception; Proteins; Public Health; Recovery; Research; Sensory; Stimulus; Stretching; Structure; Symptoms; Testing; Time; Touch sensation; Work; base; biophysical analysis; crosslink; deletion analysis; human disease; innovation; insight; mechanical force; mechanical stimulus; mechanotransduction; mutant; polyposis; sensor; stomatocytic anemia; vibration; voltage

Piezo1 and Piezo2 ion channels are essential for our senses of touch and proprioception, and the detection of lung stretch and vascular blood flow. As of today, 8 distinct human diseases have been associated with 61 single-point mutations in Piezos, many of which are not obviously related to their known physiological functions. While for most mutations their effects on Piezo function are unknown, the few mutations studied thus far distinctly affect Piezo inactivation, which is itself not understood mechanistically. The overall objective of this application is a comprehensive functional characterization of all currently-known human disease-related mutations in mechanically-activated Piezo ion channels and solving the mechanism of inactivation. Our rationale is that by determining functional effects of each point-mutation and by knowing the mechanism of Piezo inactivation we take the two first steps necessary for understanding these diseases. Our central hypothesis is that single-point mutations in Piezos that have been associated with human diseases affect membrane expression, ion permeation, or open probability, and that Piezo inactivation is determined by specific structures (residues/domains) within the C-terminal-extracellular domain (CED). The scientific premise for this hypothesis is based on the facts, that i) human patients diagnosed with colorectal polyposis, dehydrated stomatocytosis, lymphatic dysplasia, hemolytic anemia, and distal arthrogryposis, Marden-Walker syndrome, Gordon syndrome, microphthalmia are associated with mutations in Piezo1 and Piezo2, respectively, that ii) inactivation is conferred by the CED and the known main target of functional modulation of Piezos by either mutations, ligands, and voltage, and iii) our own studies showing that human disease-related point-mutations that alter inactivation kinetics profoundly change transduction of repetitive mechanical stimuli, which Piezos likely encounter during mechanical vibrations, repetitive lung stretch during breathing, or pulsating blood flow upon heart beating. Our specific aims will test the following hypotheses: Aim1: Determine the effects of 61 single-point mutations on Piezo1 and Piezo2 function; Aim2: Identification of the structures and molecular mechanism of inactivation. The proposed research is innovative, because we explore the functional consequences of 61 human Piezo1 and Piezo2 disease-related single-point mutations, nearly all of which have remained uncharacterized on a functional level, and because we will identify the mechanism of inactivation and its structural correlates, both of which are currently unknown. The significance of this study is a comprehensive biophysical analysis of functional effects of Piezo point-mutations that have been associated with human diseases of unknown mechanisms, and the mechanistic and structural exploration of inactivation as their target. This knowledge will give deep insight into the mechanisms underlying these diseases and guide strategies for further mechanistic explorations, effective diagnosis and disease treatment.

压电1和压电2离子通道对于我们的触觉和本体感受至关重要，并且检测 肺拉伸和血管血流。截至今天，有8种不同的人类疾病与61 压电中的单点突变，其中许多显然与其已知生理学无关 功能。尽管对于大多数突变，它们对压电功能的影响尚不清楚，但研究了一些突变。 极大地影响了压电灭活，这本身是从机械上理解的。该应用的总体目标是在机械激活的压电离子通道中所有当前已知的与人类疾病相关的突变的全面功能表征并解决了失活的机制。我们的理由是，通过确定每个点突变的功能效应，并知道压电的机理，我们采取了理解这些疾病所需的两个第一步。我们的中心假设是，与人类疾病相关的压电中的单点突变会影响膜表达，离子渗透或开放概率，而压电灭活是由C- C-末端 - extraccractarular-tracactarular域（CED）内的特定结构（残基/结构域）确定的。该假设的科学前提是基于事实，即i）i）诊断出患有结直肠息肉病，脱水的气孔病，淋巴性发育不全，淋巴性发育不良，溶血性贫血和远端关节化的患者，与Mardon-Walker综合征，gordon综合征，Microphthalmia相关，尤多（pie）灭活由CED和已知的功能主要目标赋予 通过突变，配体和电压和iii对压电的调节，我们自己的研究表明人类 改变灭活动力学的与疾病相关的点突变深刻地改变了重复的转导 机械刺激，压电在机械振动期间可能遇到的，在 心脏跳动时呼吸或脉动血液流动。我们的具体目标将检验以下假设： AIM1：确定61个单点突变对Piezo1和Piezo2功能的影响； AIM2：识别 失活的结构和分子机制。拟议的研究具有创新性，因为我们探讨了61个人类压电和与压电疾病相关的单点突变的功能后果，几乎所有这些突变都在功能水平上保持了未表征，并且因为我们将确定灭活及其结构相关性的机制，这两种相关性目前都是未知的。这项研究的重要性是对与未知机制的人类疾病有关的压电点突变的功能效应的全面生物物理分析，以及将失活作为目标的机械和结构探索。这些知识将深入了解这些疾病的基础机制，并指导策略以进一步机理 探索，有效的诊断和疾病治疗。