Origin of hair cells in development and regeneration

毛细胞发育和再生的起源

• 批准号: 7022287
• 负责人: DAVID J KOZLOWSKI
• 金额: $ 31.53万
• 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/7022287
• 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介导听力和平衡的感觉毛细胞不可逆损伤引起的。该项目的目标是确定斑马鱼内耳中新感觉毛细胞（干细胞）的来源。感觉毛细胞的产生在鱼的整个生命周期中持续进行，并且受损的毛细胞很容易再生。我们将检验这样的假设：胚胎感觉祖细胞在胚胎后生长过程中得以维持，并为成年斑马鱼感觉上皮细胞提供持久的毛细胞来源。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来源，以及C）确定胚胎感觉细胞祖细胞是否在成熟的感觉上皮中产生具有再生能力的细胞。斑马鱼胚胎和幼虫的内耳是光学透明的并且可以通过实验获得。该提案中概述的实验结合了实验胚胎学和最先进的显微镜技术来识别体内毛细胞祖细胞。我们将使用笼中荧光素葡聚糖的双光子依赖性解禁来开发斑马鱼耳基板的高分辨率命运图，以标记单个耳基板细胞，追踪它们在发育过程中的谱系并确定它们的最终命运。这张命运图将识别感觉毛细胞的胚胎来源。使用斑马鱼幼虫，我们将确定正常周转期间和激光消融后后嵴再生毛细胞的来源。我们将通过后嵴细胞的双光子成像来研究体内感觉细胞群动态。我们的努力最终将检验以下假设：感觉（干）细胞谱系诞生于耳基板，在整个胚胎发生过程中维持，并成为幼虫耳中的祖细胞。斑马鱼感觉干细胞的识别和未来特征将有助于在其他脊椎动物（最重要的是哺乳动物）中识别它们，最终目标是开发干细胞疗法以改善耳聋和平衡障碍的影响。