Morphogenesis of the inner ear

内耳的形态发生

• 批准号: 6516258
• 负责人: GURKIRPAL S SOHAL
• 金额: $ 26.12万
• 依托单位: AUGUSTA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-04-01 至 2004-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6516258
• 关键词: cell differentiation; cell migration; cell population study; embryo /fetus; histogenesis; labyrinth; mammalian embryology; microsurgery; neural plate /tube; otocyst /otolith; quail

The long-term goal of this investigation is to understand the molecular mechanisms of morphogenesis of the inner ear and the associated congenital anomalies. The inner ear develops from the otic vesicle, formed by the invagination of a placode of cells, which in the current thinking, consists of a single cell type. This view is inconsistent with the recent findings in this laboratory indicating that a heretofore unrecognized population of cells, originating from the ventral part of the hindbrain neural tube, migrates into the otic vesicle. The contribution of these cells, termed as the Ventrally Emigrating Neural Tube (VENT) cells, to the development of the inner ear is completely unknown and its understanding is indeed the main goal of this study. The hypothesis to be tested in the study proposed here is that the VENT cells make specific contributions to the morphogenesis of the inner ear. The hypothesis will be tested in avian embryos by determining whether particular cell types or structures develop from the VENT cells and whether their failure to contribute causes specific defects in the inner ear, by using a variety of microsurgical techniques. Specific aims are: (1) Determine the cellular composition of the otic vesicle in quail embryos. (2) Determine the specific derivatives of each cell population of the otic vesicle. (3) Determine if the VENT cells are required for normal development of the inner ear. Results of this study should provide significant new information by indicating the specific derivatives and function of an additional cell population in the development of the inner ear, which would lead to a revision of one of our current concepts of inner ear development namely, all sensory organs and virtually all the cell types in the inner ear develop from a single cell type.

这项研究的长期目标是了解内耳形态发生的分子机制和相关的先天性畸形。内耳由耳囊发育而来，耳囊是由一组细胞内陷形成的，在目前的想法中，细胞是由一种单一的细胞类型组成的。这一观点与该实验室最近的发现不一致，该发现表明，迄今未被识别的细胞群体起源于后脑神经管的腹侧部分，迁移到耳囊中。这些被称为腹侧迁徙神经管(Vent)细胞对内耳发育的贡献是完全未知的，它的理解确实是本研究的主要目的。这里提出的这项研究中要检验的假设是，喷口细胞对内耳的形态发生有特殊的贡献。这一假设将在禽类胚胎中进行验证，方法是利用各种显微外科技术，确定特定的细胞类型或结构是否来自喷口细胞，以及它们的贡献失败是否会导致特定的内耳缺陷。具体目标是：(1)确定鹌鹑胚胎耳泡的细胞组成。(2)测定耳泡各细胞群的特定导数。(3)确定内耳的正常发育是否需要排气细胞。这项研究的结果将提供重要的新信息，表明额外的细胞群在内耳发育中的特定衍生物和功能，这将导致我们目前关于内耳发育的概念之一的修订，即内耳中的所有感觉器官和几乎所有细胞类型都是从单一细胞类型发育而来的。