Nanomechanics of inner-ear hair-cell transduction

内耳毛细胞转导的纳米力学

• 批准号: 10670423
• 负责人: Marcos Sotomayor
• 金额: $ 38.03万
• 依托单位: OHIO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-04-01 至 2027-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10670423
• 关键词: Aminoglycosides; Animal Model; Architecture; Atomic Force Microscopy; Binding; Binding Proteins; Brain; CDH23 gene; Cadherins; Calcium; Calcium Binding; Calcium and Integrin Binding Protein 2; Calcium-Binding Proteins; Closure by clamp; Communication; Complex; Computational Technique; Consensus; Cryoelectron Microscopy; Dimerization; Elasticity; Electrophysiology (science); Equilibrium; Event; Extracellular Domain; Filament; Goals; Hair; Hair Cells; Head Movements; Hearing; Homology Modeling; Human; Integral Membrane Protein; Integrin Binding; Ion Channel; Ions; Knockout Mice; Labyrinth; Length; Link; Lipids; Mass Spectrum Analysis; Mechanics; Mechanoreceptor Cell; Mediating; Membrane; Membrane Potentials; Membrane Proteins; Modeling; Molecular; Molecular Conformation; Molecular Structure; Mus; Mutation; N-terminal; Nature; Nuclear Magnetic Resonance; PCDH15 gene; Perception; Pore Proteins; Probability; Process; Property; Protein Family; Proteins; Regulation; Rest; Role; Sensory; Sensory Disorders; Set protein; Signal Transduction; Spectrum Analysis; Speed; Spottings; Stretching; Structural Models; Structure; Testing; biophysical analysis; biophysical techniques; cellular transduction; computerized tools; deafness; dimer; experimental study; genetic deafness; hearing impairment; human model; improved; insight; link protein; mechanical force; mechanical stimulus; mechanotransduction; member; microscopic imaging; molecular dynamics; monomer; mutant; nanomechanics; ototoxicity; potassium ion; protein function; response; simulation; sound; structural determinants; vibration

PROJECT SUMMARY Vibrations from sound and mechanical stimuli from head movements are transformed into electrochemical signals for brain processing by inner-ear hair-cell mechanoreceptors mediating our senses of hearing and balance. Essential to hair-cell function are the proteins that form its mechanotransduction apparatus comprised of a fine tip-link filament that pulls on an ion channel complex to trigger sensory perception. The tip-link filament is formed by cadherin-23 (CDH23) and protocadherin-15 (PCDH15) proteins while the ion channel complex is thought to be formed by members of the transmembrane channel-like protein family TMC1 and TMC2, the transmembrane inner ear protein TMIE, and the tetraspan membrane protein of hair-cell stereocilia TMHS (also known as LHFPL5). In addition, the calcium and integrin binding protein CIB2 binds to TMC channels to regulate mechanotransduction. All these proteins are important for hearing and balance and are involved in inherited deafness, yet their molecular structures and the functional architecture of the transduction complex they form are poorly understood. The overall long-term goal of this project is to reveal the structural determinants of function for the proteins forming the inner-ear tip link and transduction ion channel complex. In Aim 1, we will use cryo-electron microscopy, high-speed atomic force microscopy, and molecular dynamics simulations to study the full-length extracellular domains of CDH23 and PCDH15 and thereby establish the structural determinants of tip-link function in inner ear mechanotransduction. In Aim 2, we will generate testable predictions using microsecond-long molecular dynamics simulations with biasing membrane potentials to characterize permeation of ions and ototoxic aminoglycosides through experimentally validated structural models of TMC protein pores. In Aim 3, we will use various computational and biophysical techniques, including nuclear magnetic resonance and native mass spectrometry, to explore regulatory mechanisms of transduction by CIB proteins. Results obtained from the proposed experiments and simulations will provide an initial and dynamic molecular view of the protein components of the inner ear mechanotransduction apparatus as we advance to understand its architecture and function in normal and impaired hearing and balance.

项目摘要 来自声音和头部运动的机械刺激的振动被转化为电化学的 内耳毛细胞机械感受器介导我们的听觉， 平衡毛细胞功能所必需的是形成其机械传导装置的蛋白质， 一种精细的尖端连接丝，它拉动离子通道复合体以触发感官知觉。提示链接 纤维由钙粘蛋白-23（CDH 23）和原钙粘蛋白-15（PCDH 15）蛋白形成，而离子通道 复合物被认为由跨膜通道样蛋白家族TMC 1的成员形成， TMC 2、跨膜内耳蛋白TMIE和毛细胞静纤毛的四跨膜蛋白 TMHS（也称为LHFPL 5）。此外，钙和整联蛋白结合蛋白CIB 2结合TMC 调节机械传导的通道。所有这些蛋白质对听力和平衡都很重要， 参与遗传性耳聋，但他们的分子结构和功能架构的转导 它们所形成的复合体却知之甚少。该项目的总体长期目标是揭示 形成内耳末梢连接和转导离子的蛋白质的功能的结构决定因素 通道复合体在目标1中，我们将使用冷冻电子显微镜，高速原子力显微镜， 分子动力学模拟研究CDH 23和PCDH 15的全长胞外结构域， 从而建立了内耳机械传导中tip-link功能的结构决定因素。在目标2中， 将使用带有偏置的微秒级分子动力学模拟生成可测试的预测 膜电位来表征离子和耳毒性氨基糖苷类药物通过实验的渗透 TMC蛋白孔的验证结构模型。在目标3中，我们将使用各种计算和生物物理 技术，包括核磁共振和天然质谱，以探索调控 CIB蛋白的转导机制。从拟议的实验和模拟获得的结果 将提供内耳蛋白质成分的初始和动态分子视图 机械转导装置，因为我们进一步了解其结构和功能，在正常和 听力和平衡受损。

项目成果

Beyond Cell-Cell Adhesion: Sensational Cadherins for Hearing and Balance.

• DOI: 10.1101/cshperspect.a029280
• 发表时间: 2018-09-04
• 期刊: Cold Spring Harbor perspectives in biology
• 影响因子: 7.2
• 作者: Jaiganesh A;Narui Y;Araya-Secchi R;Sotomayor M
• 通讯作者: Sotomayor M

Mini-PCDH15 gene therapy rescues hearing in a mouse model of Usher syndrome type 1F.

• DOI: 10.1038/s41467-023-38038-y
• 发表时间: 2023-04-26
• 期刊: NATURE COMMUNICATIONS
• 影响因子: 16.6
• 作者: Ivanchenko, Maryna V.;Hathaway, Daniel M.;Klein, Alex J.;Pan, Bifeng;Strelkova, Olga;De-la-Torre, Pedro;Wu, Xudong;Peters, Cole W.;Mulhall, Eric M.;Booth, Kevin T.;Goldstein, Corey;Brower, Joseph;Sotomayor, Marcos;Indzhykulian, Artur A.;Corey, David P.
• 通讯作者: Corey, David P.

Tuning Inner-Ear Tip-Link Affinity Through Alternatively Spliced Variants of Protocadherin-15.

• DOI: 10.1021/acs.biochem.7b01075
• 发表时间: 2018-03-20
• 期刊: Biochemistry
• 影响因子: 2.9
• 作者: Narui Y;Sotomayor M
• 通讯作者: Sotomayor M