Mechanosensor Development, Function and Dysfunction

机械传感器的发展、功能和功能障碍

• 批准号: 7857718
• 负责人: Ulrich Mueller
• 金额: $ 8.96万
• 依托单位: SCRIPPS RESEARCH INSTITUTE, THE
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-17 至 2010-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7857718
• 关键词: Adaptor Signaling Protein; Adhesions; Affect; Alleles; Alternative Splicing; Biochemical; Cell Adhesion Molecules; Cell physiology; Cells; Cellular Morphology; Child; Cochlea; Complex; Cytoplasmic Tail; Data; Defect; Development; Disease; Disease Outcome; Electrophysiology (science); Engineering; Filament; Functional disorder; Funding; Gene Mutation; Genes; Goals; Hair; Hair Cells; Health; Hearing; Human; Individual; Integral Membrane Protein; Laboratories; Labyrinth; Lead; Libraries; Link; Maintenance; Mediating; Modeling; Molecular; Morphogenesis; Morphology; Mus; Mutation; Pathway interactions; Patients; Pattern; Peptide Hydrolases; Presbycusis; Process; Property; Protein Binding; Protein Isoforms; Proteins; Publishing; RNA Splicing; Role; Signal Transduction; Site; Stereocilium; Technology; Testing; Two-Hybrid System Techniques; Usher Syndrome; Variant; Yeasts; aging population; base; deafness; design; disease phenotype; extracellular; gene function; hearing impairment; human CDH23 protein; human disease; mature animal; novel; protein complex; yeast two hybrid system

DESCRIPTION (provided by applicant): The long-term goal of my laboratory is to elucidate the mechanisms that control mechanoelectrical transduction (MET) in hair cells, and the defects in this process that cause deafness. We propose here to study the function of the cell adhesion molecules cadherin 23 (CDH23) and protocadherin 15 (PCDH15) in hair cell function and disease. Previous studies have shown that CDH23 and PCDH15 are required for hair bundle development. Recent findings show that CDH23 and PCDH15 are components of extracellular filaments that connect stereocilia not only in developing but also in functionally mature hair cells. Based on these findings and new preliminary data, we hypothesis that CDH23 and PCDH15 are components of larger transmembrane signaling complexes in hair cells that control not only hair bundle morphogenesis but also MET. We predict that alternative splicing regulates the assembly and function of these protein complexes. To test our hypothesis, we will: (i) Determine the function of CDH23 for MET using genetically modified mice that were designed to circumvent developmental hair cell defects that are associated with CDH23 null alleles; (ii) define the function of PCDH15 splice variants for hair cell development and MET; (iii) isolate by yeast-two-hybrid assays novel components of CDH23 and PCDH15 dependent adhesion complexes in hair cells; (iv) analyze mouse lines with mutations in CDH23 that mimic mutations in patients suffering from Usher Syndrome 1D and autosomal recessive deafness DFNB12. We anticipate that mutations that are associated with different disease phenotypes affects distinct aspects of CDH23 function in hair cells. Deafness is a major health problem. 1 in 1000 children is born with hearing impairment and large parts of the aging population are afflicted by age-related hearing loss. In recent years, dramatic progress has been made in identifying gene mutations that cause deafness, but we know comparatively little about the mechanisms by which mutations in the affected genes cause deafness. We propose here to study the function of two genes that have been linked to deafness, Cdh23 and Pcdh15, in hair cells. Based on published and preliminary data, we anticipate that the two genes are required both for the development and function of mechanosensory hair cells, and that different mutations in the two genes that cause syndromic and non-syndromic forms of deafness affect distinct aspects of gene function in hair cells.

描述（由申请人提供）：我的实验室的长期目标是阐明毛细胞中控制机电转导（MET）的机制，以及该过程中导致耳聋的缺陷。我们在此建议研究细胞粘附分子钙粘蛋白 23 (CDH23) 和原钙粘蛋白 15 (PCDH15) 在毛细胞功能和疾病中的功能。先前的研究表明CDH23和PCDH15是发束发育所必需的。最近的研究结果表明，CDH23 和 PCDH15 是细胞外丝的组成部分，不仅在发育中而且在功能成熟的毛细胞中连接静纤毛。基于这些发现和新的初步数据，我们假设 CDH23 和 PCDH15 是毛细胞中较大跨膜信号复合物的组成部分，该复合物不仅控制发束形态发生，还控制 MET。我们预测选择性剪接调节这些蛋白质复合物的组装和功能。为了检验我们的假设，我们将： (i) 使用转基因小鼠确定 CDH23 对 MET 的功能，这些小鼠旨在规避与 CDH23 无效等位基因相关的发育性毛细胞缺陷； (ii) 定义 PCDH15 剪接变体对于毛细胞发育和 MET 的功能； (iii)通过酵母双杂交测定分离毛细胞中CDH23和PCDH15依赖性粘附复合物的新成分； (iv) 分析具有 CDH23 突变的小鼠品系，这些突变模仿患有 Usher 综合征 1D 和常染色体隐性耳聋 DFNB12 患者的突变。我们预计与不同疾病表型相关的突变会影响毛细胞中 CDH23 功能的不同方面。耳聋是一个主要的健康问题。每 1000 名儿童中就有 1 名出生时就有听力障碍，大部分老年人口都患有与年龄相关的听力损失。近年来，在识别导致耳聋的基因突变方面取得了巨大进展，但我们对受影响基因突变导致耳聋的机制知之甚少。我们在此建议研究毛细胞中与耳聋相关的两个基因 Cdh23 和 Pcdh15 的功能。根据已发表的初步数据，我们预计这两个基因是机械感觉毛细胞的发育和功能所必需的，并且导致综合征型和非综合征型耳聋的两个基因的不同突变会影响毛细胞中基因功能的不同方面。