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.

Piezo1 和 Piezo2 离子通道对于我们的触觉和本体感觉以及检测 肺舒张和血管血流量。截至目前，8 种不同的人类疾病已与 61 种疾病相关 Piezos 中的单点突变，其中许多与其已知的生理学没有明显关系 功能。虽然对于大多数突变来说，它们对压电功能的影响尚不清楚，但对少数突变进行了研究 显着影响压电失活，这本身在机械上尚不为人所知。该应用的总体目标是对机械激活压电离子通道中所有当前已知的人类疾病相关突变进行全面的功能表征，并解决失活机制。我们的理由是，通过确定每个点突变的功能效应并了解压电失活的机制，我们采取了了解这些疾病所需的前两个步骤。我们的中心假设是，与人类疾病相关的 Piezo 中的单点突变会影响膜表达、离子渗透或开放概率，并且 Piezo 失活是由 C 端细胞外的特定结构（残基/结构域）决定的域（CED）。这一假设的科学前提基于以下事实：i) 被诊断患有结直肠息肉病、脱水性口细胞增多症、淋巴管发育不良、溶血性贫血和远端关节挛缩症、Marden-Walker 综合征、Gordon 综合征、小眼症的人类患者与 Piezo1 突变相关和 Piezo2，分别表明 ii) 失活是由 CED 和已知的功能性主要目标赋予的 通过突变、配体和电压来调节压电，以及 iii) 我们自己的研究表明，人类 改变失活动力学的疾病相关点突变深刻改变了重复基因的转导 机械刺激，压电在机械振动期间可能遇到的机械刺激，重复的肺部拉伸 呼吸，或心脏跳动时的脉动血流。我们的具体目标将检验以下假设： 目的1：确定61个单点突变对Piezo1和Piezo2功能的影响；目标2：识别 失活的结构和分子机制。拟议的研究具有创新性，因为我们探索了 61 种人类 Piezo1 和 Piezo2 疾病相关单点突变的功能后果，几乎所有这些突变在功能水平上仍未得到表征，并且因为我们将确定失活机制及其结构两者之间的相关性，目前尚不清楚。这项研究的意义在于对与未知机制的人类疾病相关的压电点突变的功能效应进行全面的生物物理学分析，并以失活为目标进行机制和结构探索。这些知识将深入了解这些疾病的机制，并指导进一步的机制策略。 探索、有效诊断和疾病治疗。