Origin of hair cells in development and regeneration

毛细胞发育和再生的起源

• 批准号: 6649549
• 负责人: DAVID J KOZLOWSKI
• 金额: $ 32.29万
• 依托单位: AUGUSTA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-04-01 至 2008-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6649549
• 关键词: cell biology; cell cycle; cell differentiation; cell population study; confocal scanning microscopy; ear hair cell; embryogenesis; epithelium; fluoresceins; histogenesis; immunocytochemistry; nonmammalian vertebrate embryology; regeneration; stem cells; zebrafish

DESCRIPTION (provided by applicant): Auditory and vestibular disorders result from irreversible damage to sensory hair cells that mediate hearing and balance. The goal of this project is to identify sources of new sensory hair cells (stem cells) in the zebrafish inner ear. Sensory hair cell production continues throughout the life of fish and damaged hair cells are readily regenerated. We will test the hypothesis that embryonic sensory progenitor cells are maintained during postembryonic growth and provide a persistent source of hair cells in the adult zebrafish sensory epithelia. We will: A) Determine the embryonic source of sensory hair cells, B) Determine the postembryonic source of hair cells in a sensory epithelium, and C) Determine if embryonic sensory cell progenitors give rise to regeneration-competent cells in a mature sensory epithelium. The inner ears of zebrafish embryos and larvae are optically transparent and experimentally accessible. Experiments outlined in this proposal combine experimental embryology and state-of-the-art microscopy to identify hair cell progenitors in vivo. We will develop a high-resolution fate map of the zebrafish otic placode using two-photon dependant uncaging of caged fluorescein dextran to label single otic placode cells, trace their lineages during development and determine their ultimate fates. This fate map will identify the embryonic source of sensory hair cells. Using zebrafish larvae, we will determine the source of regenerated hair cells in the posterior crista during normal turnover and after laser ablation. We will investigate sensory cell population dynamics in vivo by two-photon imaging of cells in the posterior crista. Our efforts will culminate in a test of the hypothesis that sensory (stem) cell lineages are born in the otic placode, maintained throughout embryogenesis, and become progenitor cells in the larval ear. Identification and future characterization of sensory stem cells in the zebrafish will aid their identification in other vertebrates (most importantly mammals) with the ultimate goal of developing stem cell therapies to ameliorate the effects of deafness and balance disorders.

描述（由申请人提供）：听觉和前庭疾病是由于对介导听力和平衡的感觉毛细胞的不可逆转损害而造成的。该项目的目的是确定斑马鱼内耳中新的感觉毛细胞（干细胞）的来源。在鱼类的整个生命中，感官毛细胞的产生持续，并且毛细胞很容易再生。我们将检验以下假设：胚胎后生长期间保持胚胎感觉祖细胞，并在成年斑马鱼感觉上皮中提供持续的毛细胞来源。我们将：a）确定感觉毛细胞的胚胎来源，b）确定感觉上皮中毛细胞的胚胎后源，c）确定胚胎感觉细胞祖细胞是否会在成熟的感觉上皮中产生富有再生的细胞。斑马鱼胚胎和幼虫的内耳在光学上是透明的，可以在实验上访问。该提案中概述的实验结合了实验性胚胎学和最先进的显微镜，以鉴定体内毛细胞祖细胞。我们将使用笼中荧光素葡萄糖的两光子依赖性的卵形呈卵形，以在发育过程中追踪其谱系并确定其最终命运。该命运图将确定感觉毛细胞的胚胎来源。使用斑马鱼幼虫，我们将在正常周转期间和激光消融后确定后Crista中再生毛细胞的来源。我们将通过后Crista中细胞的两光片成像在体内研究感觉细胞种群动力学。我们的努力将在检验的假设中达到顶峰，即感觉（STEM）细胞谱系诞生于Otod Placode，始终保持整个胚胎发生，并成为幼虫耳中的祖细胞。斑马鱼中感觉干细胞的鉴定和未来表征将有助于其在其他脊椎动物（最重要的是哺乳动物）中的鉴定，其最终目的是开发干细胞疗法以减轻聋和平衡疾病的影响。