Mitochondrial function and dysfunction in hair cells

项目摘要 影响线粒体功能的30多个基因的遗传破坏导致听力损失。我们建议 理解机械感觉毛细胞中代表性突变的细胞后果。我们 初步研究表明，毛细胞在成熟时经历快速的线粒体生物合成， 线粒体对机械感觉信号有积极的反应。我们建议进行研究， 线粒体的生长和功能，重点是线粒体之间的专门连接的作用， 和内质网（ER）。越来越多的证据支持ER-线粒体连接的作用 调节线粒体代谢、动力学和应激，以及在受调节的细胞死亡中发挥核心作用。 我们提出了使用斑马鱼侧线毛细胞的实时成像实验，该系统适用于 研究体内细胞功能。我们将评估头发中线粒体的生长、氧化和ATP利用率 细胞，并确定破坏ER-线粒体通讯的后果。我们将测量 线粒体对机械刺激的反应。使用CRISPR，我们将产生斑马鱼， 人类线粒体突变模型，以评估毛细胞的功能后果。我们的实验 将揭示毛细胞中线粒体的潜在基本机制，以及这些机制是如何运作的。 在人类听力损失中的作用。

PROJECT SUMMARY Genetic disruptions of over thirty genes affecting mitochondrial functions result in hearing loss. We propose to understand the cellular consequences of representative mutations in mechanosensory hair cells. Our preliminary studies demonstrate that hair cells undergo rapid mitochondrial biogenesis as they mature, and that mitochondria actively respond to mechanosensory cues. We propose studies to understand the regulation of mitochondrial growth and function, focusing on the roles of specialized connections between mitochondria and the endoplasmic reticulum (ER). Growing evidence supports a role for ER-mitochondrial junctions regulating mitochondrial metabolism, dynamics, and stress and for playing a central role in regulated cell death. We propose experiments using live imaging of hair cells in the zebrafish lateral line, a system amenable to study of cellular functions in vivo. We will assess mitochondrial growth, oxidation and ATP utilization in hair cells, and determine the consequences of disrupting ER-mitochondrial communication. We will measure changes in mitochondria in response to mechanical stimuli. Using CRISPR, we will generate zebrafish models of human mitochondrial mutations to assess functional consequences for hair cells. Our experiments will reveal potentially fundamental mechanisms of mitochondria in hair cells and how these mechanisms go awry in human hearing loss.