ZEBRAFISH: A POTENTIAL MODEL FOR MAMMALIAN HAIR CELL DEATH AND REGENERATION

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得主要资金， 因此可以在其他CRISP条目中表示。所列机构为 中心，不一定是研究者的机构。 听觉毛细胞是脊椎动物的感觉细胞，负责将声音信号传递到神经元，从而提供听觉能力。在哺乳动物中，当这些终末分化的细胞受损或丢失时，结果是永久性听力损失，因为丢失的哺乳动物毛细胞不能再生。在鱼类和鸟类中，受损的听觉上皮细胞具有再生新毛细胞的能力，从而恢复听力。最近的研究表明，金鱼在噪声暴露后表现出结构（毛细胞）和功能（听力）的恢复。为了充分了解正常的细胞过程导致鱼类再生，特定基因如何介导毛细胞生长（增殖和转分化）的知识是必不可少的。该项目的总体目标是研究斑马鱼毛细胞再生的过程，因为斑马鱼已经成为研究许多细胞途径基因表达的生产模型。目前的建议有三个目标针对这一目标：1）确定时间过程中的毛细胞死亡和再生的噪音暴露斑马鱼（免疫细胞化学）; 2）确定噪声暴露后斑马鱼听力功能恢复的时间过程（使用听觉脑干反应）;（3）利用rtPCR和微阵列技术检测斑马鱼耳毛细胞死亡和再生过程中的基因表达。我们最初感兴趣的是检查三个基因（p27 Kip 1，Atoh 1和Rb 1）的表达。这些基因最近被证明可以调节哺乳动物毛细胞的发育。我们已经进行了一个微阵列实验，检查毛细胞生成过程中的基因表达，上述三个感兴趣的基因没有高度调节，但生长激素和其他一些基因。我们最近验证了我们的微阵列实验与实时PCR使用显着调控基因。这些研究将为毛细胞再生研究的未来研究提供基础，并可能在毛细胞增殖和治疗耳聋的新疗法开发之间建立联系方面至关重要。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Auditory hair cells are the sensory cells that transduce acoustical signals into neural ones in vertebrates, thus providing the ability to hear. In mammals, when these terminally-differentiated cells are damaged or lost, the result is permanent loss of hearing since lost mammalian hair cells do not regenerate. In fish and birds, damaged auditory sensory epithelia have the capability of regenerating new hair cells, resulting in recovery of hearing. Recent studies show that goldfish exhibit both structural (hair cells) and functional (hearing) recovery following noise exposure. To fully understand what normal cellular processes lead to regeneration in fishes, knowledge of how specific genes mediate hair cell growth (proliferation and transdifferentiation) is essential. The overall goal of this project is to study the process of hair cell regeneration in zebrafish, since zebrafish has become a productive model for studying the gene expression of many cellular pathways. The current proposal has three aims directed at this goal: 1) to determine the time course of hair cell death and regeneration in noise-exposed zebrafish (using immunocytochemistry); 2) to determine the time course of functional recovery of hearing following noise exposure in zebrafish (using auditory brainstem response); and 3) to examine gene expression during the process of hair cell death and regeneration in the zebrafish ear using rtPCR and microarray analysis. We were initially interested in examining expression of three genes (p27Kip1, Atoh1, and Rb1). These genes have recently been shown to regulate hair cell development in mammals. We have performed a microarray experiment that examined gene expression during the process of hair cell generation, and the three genes of interest above were not highly regulated, but growth hormone and a number of other genes were. We recently validated our microarray experiments with real-time PCR using significantly regulated genes. These studies will provide a basis for future investigations in hair cell regeneration research and may be critical in establishing a link between hair cell proliferation and development of new therapeutics to treat deafness.