DEVELOPMENT OF THE XENOPUS ACOUSTICO-VESTIBULAR SYSTEM

描述：本研究的目标是获得一个综合的观点， 感觉器官发育和成熟的基础机制 内耳 实验将集中在听觉和前庭 两栖动物非洲爪蟾的毛细胞。 拟议的研究将 利用非洲爪蟾作为经典系统提供的优势， 发展研究 内耳的钾离子通道将是一个 这些调查的中心主题，并将用于测试假设 毛细胞的发育和分化 其中一个主要目标是 研究是建立钾通道基因表达模式， 发育中的内耳 电生理学方法（膜片钳）将 用于研究游离毛细胞中离子通道的功能。 分子 技术将用于克隆耳钾通道（RT-PCR，RACE， 重组DNA），并将与解剖学方法（原位 杂交）以检查耳中钾通道mRNA的表达。 的 本研究的具体目的是检验以下假设：（1）一个 与drk 1同源的外向钾通道在非洲爪蟾中表达 内耳，（2）爪蟾囊状毛细胞束形态可以 与囊状毛细胞电膜特性相关;（3）囊状毛细胞膜电位与囊状毛细胞膜电位的关系 非洲爪蟾囊状毛细胞中表达的离子通道类型随着 毛细胞发育，（4）头发之间离子吸引剂的性质不同 囊状爪蟾、两栖动物乳头和基底乳头的细胞。 实验结果有望推进对以下问题的基本理解： 毛细胞多样性的遗传基础，以及毛细胞的遗传控制。 耳发育 这项研究的长期目标是奠定 为未来的研究奠定了基础，这些研究将确定基因如何在细胞中表达。 穗在发育和再生过程中受到调节。 结果进行 调查将提供可用于发展的基本知识， 有效治疗听力损失，如由创伤或 遗传性疾病。

DESCRIPTION: The goal of this research is to gain an integrated view of the mechanisms that underlie development an, maturation of the sensory endorgans of the inner ear. Experiments will focus on the auditory and vestibular hair cells of the amphibian, Xenopus laevis. The proposed research will exploit the advantages that Xenopus offers as a classical system for developmental studies. The potassium channels of the inner ear will be a central subject of these investigations, and will be used to test hypotheses about hair cell development and differentiation. A major objective of this research is to establish the pattern of potassium channel gene expression in the developing inner ear. Electrophysiological methods (patch clamp) will be used to study ion channel function in dissociated hair cells. Molecular techniques will be used to clone ear potassium channels (RT-PCR, RACE, recombinant DNA) and will be combined with anatomical methods (in situ hybridization) to examine potassium channel mRNA expression in the ear. The specific aims of this research are to test the following hypotheses: (1) An outward potassium channel homologous to drkl is expressed in the Xenopus inner ear, (2) Xenopus saccular hair cell bundle morphology can be correlated with saccular hair cell electrical membrane properties, (3) The types of ion channels expressed in Xenopus saccular hair cells change as hair cells develop, (4) The properties of ion charmers differ between hair cells of the Xenopus sacculus, amphibian papilla, and basilar papilla. Experimental results are expected to advance fundamental understanding about the genetic basis of hair cell diversity, and about the genetic control of ear development. The long-term goal of this research is to lay the foundation for future studies that will determine how genes expressed in the ear are regulated during development and regeneration. Results of these investigations will provide essential knowledge that can be used to develop effective treatments for hearing loss such as that caused by trauma or genetic disorders.