Role of Gas2 in cytoskeletal architecture, support cell stiffness, and cochlear function

Gas2 在细胞骨架结构、支持细胞刚度和耳蜗功能中的作用

基本信息

批准号：
9816749
负责人：
DOUGLAS J EPSTEIN
金额：
$ 47.77万
依托单位：
UNIVERSITY OF PENNSYLVANIA
依托单位国家：
美国
项目类别：
财政年份：
2003
资助国家：
美国
起止时间：
2003-08-01 至 2024-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9816749
关键词：
Acoustic Nerve Actins Address Adult Affect Age Animal Model Animals Applications Grants Architecture Atomic Force Microscopy Auditory Brain Cell surface Cells Cellular Morphology Clinical Cochlea Cochlear duct Complex Coupled Cytoskeleton Data Defect Developed Countries Developing Countries Development Embryo Exhibits Female Fertility Future GAS2 gene GJB2 gene Gap Junctions Gene Mutation Genes Genetic Predisposition to Disease Growth Hair Cells Hearing Human Inherited Inner Hair Cells Knockout Mice Labyrinth Length Mammals Mechanics Microtubule Bundle Microtubule Stabilization Microtubules Modeling Molecular Mus Neonatal Nerve Fibers Newborn Infant Optical Coherence Tomography Organ Organ of Corti Outer Hair Cells Ovarian Pathogenicity Pathway interactions Pattern Perrault syndrome Play Plus End of the Microtubule Proteins Role Sensorineural Hearing Loss Sensory Signal Transduction Specificity Structure Supporting Cell Symptoms Tensile Strength Testing Viral alpha Tubulin base cell type crosslink design early onset experimental study gene therapy genetic regulatory protein hearing impairment hearing restoration human model inner ear development inner ear diseases insight link protein live cell imaging mechanical force mechanical properties mouse model novel postnatal prevent hearing loss repaired sound vibration

项目摘要

The identification of gene mutations associated with hearing loss in humans and animal models has contributed greatly to our understanding of cell type specific functions in the inner ear. Despite this progress, the cause of inherited forms of hearing loss still remains unknown in many cases, suggesting that the discovery of new genes associated with sensorineural hearing loss (SNHL) is far from saturated. To fill this gap, we performed a screen for novel regulators of cochlear development and identified several genes that are predicted to play important roles in cochlear function. We generated a mouse knockout for one of these genes, Growth arrest specific 2 (Gas2), encoding a putative cytoskeletal regulatory protein. Gas2 knockout mice display severe hearing loss with no alterations in inner ear development at embryonic stages. Instead, we propose that the cause of hearing loss is due to a progressive destabilization of the microtubule cytoskeleton in pillar and Deiters’ cells, two specialized support cells in the organ of Corti that are thought to provide tensile strength and a structural framework for transferring mechanical forces during sound-evoked vibrations. The experiments in this grant proposal are designed to transform our understanding of the role that support cells play in cochlear function. Firstly, we will test the hypothesis that Gas2 dependent stabilization of microtubule bundles in pillar and Deiters’ cells is required for hearing. Secondly, we will determine the influence of Gas2 and a-tubulin detyrosination on cell surface mechanical properties and microtubule dynamics. Finally, we will pursue the exciting possibility that viral delivery of Gas2 to support cells might prevent hearing loss when administered prior to the onset of symptoms in neonatal Gas2 knockout mice, and even more provocatively, might repair the cytoskeletal defects and restore hearing when administered to adults. Taken together, these experiments will clarify the proposed role of Gas2 as a microtubule and actin cross-linking protein that is required to stabilize microtubule bundles in cochlear support cells and that this activity is necessary for auditory function.

鉴定与人类和动物模型听力损失相关的基因突变极大地促进了我们对内耳细胞类型特定功能的理解。尽管取得了这些进展，遗传性听力损失的原因仍然未知许多案例表明，与感音神经性听力相关的新基因的发现损失（SNHL）远未饱和为了填补这一空白，我们对新型监管机构进行了筛选。耳蜗发育并确定了一些预计在耳蜗发育中发挥重要作用的基因我们对其中一种基因（生长停滞）进行了小鼠敲除。特异性 2 (Gas2)，编码假定的 Gas2 敲除小鼠的细胞骨架调节蛋白。表现出严重的听力损失，但胚胎阶段内耳发育没有改变。相反，我们认为听力损失的原因是由于听力损失的逐渐不稳定造成的。柱细胞和 Deiters 细胞中的微管细胞骨架，这是器官中的两种特殊支持细胞 Corti 被认为提供拉伸强度和用于转移的结构框架本拨款提案中的实验是声音诱发振动期间的机械力。旨在改变我们对支持细胞在耳蜗功能中所发挥作用的理解。首先，我们将检验以下假设：Gas2 依赖的微管束稳定性其次，我们将确定听力的影响。 Gas2 和 a-微管蛋白去酪氨酸对细胞表面机械性能和微管的影响最后，我们将追求令人兴奋的可能性，即通过病毒传递 Gas2 来支持。在新生儿症状出现之前施用细胞可能会预防听力损失更令人兴奋的是，Gas2 基因敲除小鼠可能会修复细胞骨架缺陷，综合起来，这些实验将阐明成年人的听力。 Gas2 作为微管和肌动蛋白交联蛋白的拟议作用是稳定耳蜗支持细胞中的微管束，并且这种活性对于听觉功能。