Global analysis of bundle protein transport in mouse vestibular hair cells

描述(申请人提供)：对声音和平衡的感知取决于发束的机械感觉功能，发束是一组充满肌动蛋白的立体纤毛，从听觉和前庭毛细胞的根尖表面突起。对耳聋相关基因的研究导致了一些定位于发束的蛋白质的鉴定，这些蛋白质有助于发束的发育和功能[1]。尽管有这些进展，但组成发束并调节其成熟、维持和功能的完整蛋白质网络仍未得到很好的确定。尽管人们对肌球蛋白运输到肌束的机制也知之甚少，但越来越多的证据表明，肌球蛋白马达蛋白可能扮演着重要的角色[2]。这项提议的目标是确定束蛋白 在毛束形成过程中，肌球蛋白-VIIa(MYO7A)被运输到毛束并保持在毛束内，并检验肌球蛋白-VIIa(MYO7A)在这些蛋白质的运输中发挥作用的假设。使用蛋白质组学方法以及其他生化技术，本提案的目的将1)以公正的方式识别在发束组装期间和之后在发束内丰富的蛋白质网络，2)确定MYO7A是否在特定蛋白质到发束的运输中发挥作用，以及3)识别这些发束特定蛋白质中的哪些直接或 间接与MYO7A相互作用。这些研究的结果将大大有助于我们对毛细胞束组装和功能的分子理解，并有助于指导毛细胞修复和再生治疗策略的发展。

DESCRIPTION (provided by applicant): The perception of sound and balance depends on the mechanosensory function of the hair bundle, a group of actin-filled stereocilia that project from the apical surface of auditory and vestibular hair cells. The study of deafness-linked genes has led to the identification of a number of proteins that are localized to the hair bundle and contribute to its development and function [1]. Despite these advances, the complete network of proteins that constitute the hair bundle and regulate its maturation, maintenance and function remain poorly defined. Although the mechanisms by which proteins are specifically transported to the bundle are also poorly understood, accumulated evidence suggests that myosin motor proteins may play important roles [2]. The goal of this proposal is to identify the bundle proteins that are transported to and maintained within the hair bundle during its formation and to test the hypothesis that myosin-VIIa (MYO7A) plays a role in the transport of these proteins. Using proteomics approaches as well as other biochemical techniques, the aims in this proposal will 1) identify in an unbiased manner the protein networks that are enriched within the hair bundle during and after bundle assembly, 2) determine whether MYO7A plays a role in the transport of specific proteins to the bundle and 3) identify which of these bundle-specific proteins directly or indirectly interact with MYO7A. The results of these studies will significantly contribute to our molecular understanding of bundle assembly and function and could help guide the development of therapeutic strategies for hair cell repair and regeneration.