Functional development of hair cells

毛细胞的功能发育

基本信息

批准号：
7874549
负责人：
Gwenaelle S Geleoc
金额：
$ 31.46万
依托单位：
UNIVERSITY OF VIRGINIA
依托单位国家：
美国
项目类别：
财政年份：
2007
资助国家：
美国
起止时间：
2007-07-01 至 2011-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7874549
关键词：
Adenovirus Vector Animals Auditory Biological Assay Brain Candidate Disease Gene Cell physiology Cells Cochlea Complex Development Dominant-Negative Mutation Electrophysiology (science)Gene Expression Gene Family Gene Targeting Genes Genetic Hair Cells Head Movements Hearing In Vitro Investigation Isopropyl Thiogalactoside Labyrinth Location Maps Messenger RNA Molecular Mus Mutate Myosin ATPase Normal Cell Organ Organ of Corti Pattern Physiological Positioning Attribute Property Proteins RNA Interference Research Research Personnel Reverse Transcriptase Polymerase Chain Reaction Role Sensory Signal Transduction Staging System Testing Time Transgenic Mice base cellular transduction deafness design drinking water equilibration disorder gene function hearing impairment human CDH23 protein in vivo in vivo Model interest mRNA Expression mutant novel programs promoter receptor regional difference sound spatiotemporal transgene expression

项目摘要

DESCRIPTION (provided by applicant): Hair cells of the inner ear have the exclusive role of converting head movements and sound into electrical signals that are transmitted to the brain. How hair cells accomplish this unique function has been the focus of intense and fruitful investigation over the last quarter century. A few of the molecular players have been identified, however the identity of the transduction channel itself and much of the associated transduction complex remains elusive. The lag in molecular identification of the hair cell transduction complex is a consquence of the low number of hair cells per sensory organ (2-16 thousand) and the few tranduction molecules per cell (50-100). To circumvent these difficulties we propose a novel and compelling approach that will take advantage of the precise temporal and regional developmental pattern in the acquisition of mechanotransduction in the mouse cochlea. In the first part of this project we will determine when hair cells become mechanosensitive as a function of developmental stage and position along the cochlea and we will characterize tonotopic differences in the properties of mechanotransduction. We hypothesize that genes required for hair cell mechanosensation will be enriched around the time of transduction onset. Thus, we will analyze the spatio-temporal pattern of gene expression for various candidate molecules during the development of the Organ of Corti. Molecules with expression patterns that parallel the pattern of acquisition of mechanosensitivity will be identifed as transduction candidates. To determine the precise role of the candidate molecules we will inhibit their functional expression and use in vitro and in vivo assays for disruption of hair cell and auditory function. In particular, we will use RNA interference and dominant- negative inhibition and assay for suppression of mechanotransduction in developing hair cells. To examine gene function in vivo we will generate inducible, hair cell expression of mutant candidate genes and assay for loss of auditory function. Lay summary: This study is designed to identify the genetic basis of deafness and balance disorders. We will examine the sensory cells of the normal inner ear during development to identify when the cells begin to function and which genes are turned on. We will use several genetic tricks to block the activity of those genes and examine their effect on hearing. Loss of hearing function will confirm which genes are necessary for normal hearing and which genes may cause genetic deafness when mutated.

描述（由申请人提供）：内耳的毛细胞具有将头部运动和声音转化为传输到大脑的电信号的独特作用。毛细胞如何实现这种独特的功能一直是过去四分之一个世纪以来深入而富有成效的研究的焦点。一些分子参与者已经被识别，但是转导通道本身和许多相关转导复合物的身份仍然难以捉摸。毛细胞转导复合物分子鉴定的滞后是每个感觉器官的毛细胞数量较少（2-16,000）和每个细胞的转导分子很少（50-100）的结果。为了克服这些困难，我们提出了一种新颖且令人信服的方法，该方法将利用小鼠耳蜗中获得机械转导的精确时间和区域发育模式。在该项目的第一部分中，我们将确定毛细胞何时变得对机械敏感，作为发育阶段和沿耳蜗位置的函数，并且我们将描述机械转导特性中的音调差异。我们假设毛细胞机械感觉所需的基因将在转导开始时丰富。因此，我们将分析柯蒂氏器发育过程中各种候选分子的基因表达的时空模式。具有与机械敏感性获得模式平行的表达模式的分子将被识别为转导候选者。为了确定候选分子的精确作用，我们将抑制它们的功能表达，并使用体外和体内测定来破坏毛细胞和听觉功能。特别是，我们将使用 RNA 干扰和显性失活抑制和测定来抑制发育中毛细胞的机械转导。为了检查体内基因功能，我们将产生突变候选基因的诱导型毛细胞表达，并测定听觉功能的丧失。简单总结：本研究旨在确定耳聋和平衡障碍的遗传基础。我们将检查发育过程中正常内耳的感觉细胞，以确定细胞何时开始发挥作用以及哪些基因被打开。我们将使用几种遗传技巧来阻止这些基因的活动并检查它们对听力的影响。听力功能的丧失将确定哪些基因是正常听力所必需的，哪些基因突变后可能会导致遗传性耳聋。