A STUDY OF THE STRIATED ORGANELLE IN VESTIBULAR ENDORGANS

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子项目工作人员的直接资金。 在哺乳动物前庭迷路中，毛细胞能够响应跨膜电位的变化而产生轴向变形。我们对毛细胞中的机电转导的理解依赖于对细胞内结构的精确了解，并且对毛细胞生理学建模的努力同样限于已知细胞内几何形状的保真度。这项合作的重点是前庭毛细胞的超微结构。更确切地说，我们正在观察表皮下区域（表皮板下方），使用电子断层扫描来可视化和分析静纤毛束和细胞顶端区域交界处的小根结构。我们的主要兴趣是纹状细胞器（SO），一个独特的结构，位于毛细胞（听觉和前庭感觉细胞）的顶端，就在表皮板下面。它在哺乳动物I型前庭毛细胞中特别突出。我们在NCMIR的帮助下研究的中心假设是，纹状细胞器在毛细胞的顶端和基底部分之间提供结构和功能连接。这一共同努力的目标是描述这个特定细胞器的三维结构，并确定其组成部分（或至少部分组成部分）。我们的研究应呼吁：1）对感觉传导和机械传导的机制感兴趣的感觉生理学家，2）对从传入到传导装置的反馈感兴趣的神经科学家，3）对潜在的新运动蛋白、收缩元件、钙动力学以及这些机制的分子结构感兴趣的蛋白化学家，4）对肌动蛋白、分子马达、细胞骨架和线粒体感兴趣的分子和细胞生物学家，和5）显微镜和形态学家感兴趣的一个新的和优雅的结构装置。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. In the mammalian vestibular labyrinth, hair cells are capable of generating axial deformations in response to variations in transmembrane potential. Our understanding of electromechanical transduction in the hair cells depends on precise knowledge of intracellular structure, and efforts to model hair cell physiology are likewise limited to the fidelity of known intracellular geometry. This collaboration focuses on the ultrastructure of vestibular hair cells. More precisely, we are looking at the subcuticular region (below the cuticular plate), using electron tomography to visualize and analyze rootlet architecture at the junction of the stereocilia bundle and apical region of the cell. Our main interest is the striated organelle (SO), a unique structure located at the apical end of hair cells (auditory and vestibular sensory cells), just below the cuticular plate. It is particularly prominent in mammalian type I vestibular hair cells. The central hypothesis we are investigating with aid from the NCMIR is that striated organelles provide structural and functional connections between the apical and basal parts of the hair cell. The goals of this joint effort are to describe the three-dimensional structure of this particular organelle and to identify its components (or at least, some of the components). Our study should appeal to: 1) sensory physiologists interested in mechanisms of sensory transduction and mechanotransduction, 2) neuroscientists interested in feedback from afferents to the transduction apparatus, 3) protein chemists interested in potential new motor proteins, contractile elements, calcium dynamics, and the molecular architecture of these mechanisms, 4) molecular and cell biologists interested in actin, molecular motors, the cytoskeleton and mitochondria, and 5) microscopists and morphologists interested in a new and elegant structural apparatus.