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）：我实验室的长期目标是阐明毛细胞中控制机械电转导（MET）的机制，以及该过程中导致耳聋的缺陷。我们在这里提出研究细胞粘附分子钙粘蛋白23（CDH 23）和原钙粘蛋白15（PCDH 15）在毛细胞功能和疾病中的功能。先前的研究表明，CDH 23和PCDH 15是毛束发育所必需的。最近的研究表明，CDH 23和PCDH 15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CDH 23和PCDH 15是毛细胞中较大的跨膜信号复合物的组成部分，不仅控制毛束形态发生，而且还控制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）使用遗传修饰小鼠确定CDH 23对于MET的功能，所述遗传修饰小鼠被设计为规避与CDH 23无效等位基因相关的发育毛细胞缺陷;（ii）定义PCDH 15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依赖于CDH 23和PCDH 15粘附复合物的新组分;（iv）分析在CDH 23中具有突变的小鼠品系，所述突变模拟患有Usher综合征1D和常染色体隐性耳聋DFNB 12的患者中的突变。我们预计，与不同疾病表型相关的突变会影响毛细胞中CDH 23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，大部分老年人都患有与年龄有关的听力损失。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。我们建议在这里研究两个基因的功能，已链接到耳聋，Cdh 23和Pcdh 15，在毛细胞。基于已发表的和初步的数据，我们预计这两个基因都需要为机械感觉毛细胞的发展和功能，并在两个基因的不同突变，导致综合征和非综合征形式的耳聋影响不同方面的基因功能的毛细胞。