Zebrafish sensory hair cell regeneration

项目摘要 由毛细胞变性引起的听力损失是世界上最普遍的感觉障碍之一 65 - 75岁的人中有30%受到影响。在人类和哺乳动物中， 因此，任何毛细胞的损伤或损失都是永久性的。因此，迫切需要 开发人类毛细胞再生的治疗方法。与哺乳动物相比， 鱼类、鸟类和两栖动物毛细胞死亡后再生。对于毛细胞为什么会 在某些脊椎动物中再生而在另一些中则没有。这项工作的目标是阐明基因调控 斑马鱼毛细胞再生的潜在网络，结果将帮助我们确定策略，以引起 恢复哺乳动物失去的毛细胞。斑马鱼的耳朵和皮肤上都有毛细胞， 感觉水运动的感觉侧线系统。斑马鱼侧线毛的发育 细胞由与哺乳动物内耳毛细胞相同的信号通路控制，然而，它们很容易被 可以直接观察和基因操作。Notch和Wnt信号传导之间的相互作用是 对于维持祖细胞自我更新和分化之间的平衡至关重要。这项工作将扩大 通过确定其他信号通路，如Fgf和视黄酸（RA）， 有力地影响毛细胞的再生，融入这个网络。Notch，Wnt， FGF和RA途径将通过使用突变体的途径的组合操作来确定， 药物抑制剂和转基因品系。此外，基因间的相互作用，调节的平衡， 祖细胞自我更新和分化将在体内单细胞水平上进行功能性研究， 时间推移和细胞增殖/细胞命运分析的组合。这项工作的一个重要组成部分是 再生期间和途径操作后单个支持细胞的表达分析。单 细胞分析是强大的，因为在支持细胞中发现了意想不到的多样性或镶嵌性， 在批量支持细胞RNASeq分析中被掩蔽。此外，随着细胞分化，它们将整合许多 与其他细胞不同的信号这些实验将允许区分不同细胞上的细胞。 轨迹，在时间上沿着这些轨迹对它们进行沿着，并确定新的调节因素， 分化这些目标的结果将告诉我们斑马鱼毛发的基因调控网络 细胞再生，这将指导治疗的设计，以诱导哺乳动物毛细胞再生。

Project Summary Hearing loss caused by hair cell degeneration is one of the most widespread sensory disabilities in the world with 30% of people between ages 65 -75 being affected. In humans and mammals, hair cells are unable to regenerate, hence any damage or loss of hair cells is permanent. Therefore, there is an urgent need to develop therapeutic approaches for regenerating hair cells in humans. In contrast to mammals, hair cells in fishes, birds and amphibians regenerate following hair cell death. Very little is known about why hair cells regenerate in some vertebrates and not in others. The goal of this work is to elucidate the gene regulatory network underlying zebrafish hair cell regeneration, The results will help us identify strategies to elicit the restoration of lost hair cells in mammals. Zebrafish possess hair cells in their ears and in their skin as part of the sensory lateral line system that senses water movement. The development of zebrafish lateral line hair cells is controlled by the same signaling pathways as mammalian inner ear hair cells, however, they are easily accessible to direct observation and genetic manipulation. Interactions between Notch and Wnt signaling are crucial for maintaining a balance between progenitor cell self-renewal and differentiation. This work will expand this knowledge by determining how other signaling pathways, such as Fgf and retinoic acid (RA), which also robustly affect hair cell regeneration, fit into this network. The epistatic relationship between the Notch, Wnt, Fgf and RA pathways will be determined by combinatorial manipulation of pathways using mutants, pharmaceutical inhibitors and transgenic lines. In addition, gene interactions that regulate the balance of progenitor cell self-renewal and differentiation will be functionally interrogated at the single cell level in vivo with a combination of time-lapse and cell proliferation/cell fate analyses. An important component of this work is the expression analysis of individual support cells during regeneration and after pathway manipulations. The single cell analysis is powerful, as an unexpected diversity or mosaicism in support cells was discovered, which is masked in bulk support cell RNASeq analyses. In addition, as cells differentiate they will integrate many different signals from other cells over time. These experiments will allow the distinction of cells on different trajectories, temporally order them along those trajectories, and identify new regulatory factors controlling differentiation. The results of these aims will inform us of the gene regulatory network underlying zebrafish hair cell regeneration, which will guide the design of therapies to induce hair cell regeneration in mammals.