Enhancing hair cell regeneration in the mature cochlea: Modulating Sox gene control of supporting cell identity

项目总结/摘要 该项目的目标是研究关键支持细胞命运基因的丢失是否会增强 将耳蜗细胞重新编程和再生为毛细胞作为听力恢复的策略。我们有 发现成熟耳蜗的支持细胞可以被重新编程为毛细胞样细胞， Atoh 1 + Gfi 1 + Pou 4f 3联合损伤和重编程。我们还发现非感觉细胞 内沟和外沟的神经元可以用Atoh 1 + Gfi 1 + Pou 4f 3重编程，并提供第二电位 用于听力恢复的细胞群。在这里，我们针对两个Sox家族基因，调节毛细胞 但在成熟耳蜗的支持细胞和其他非感觉细胞中表达。 Sox家族成员Sox 2和Sox 10都与毛细胞的命运决定有关，因为它们各自产生异位 当一个等位基因丢失时，毛细胞会发生变化。最靠近内毛细胞的支持细胞似乎特别 在异位内毛细胞的产生中易受Sox 2和Sox 10的联合缺失的影响。 此外，初步数据表明，重编程的毛细胞样细胞不会关闭Sox 2或Sox 10 这可能限制了他们的完全命运转换。值得注意的是，Sox 2的一个等位基因的缺失增加了 再生毛细胞的数量表明它阻止了这些细胞中毛细胞的命运。 在这里，我们假设支持细胞网络的基因Sox 2和Sox 10限制了细胞的能力， 在重新编程后变成毛细胞为了验证这一假设，我们将使用转基因小鼠 将耳蜗细胞重新编程和再生为毛细胞样细胞的模型。除了重新编程， 将：i）从Corti器官中的耳蜗支持细胞中完全删除Sox 2，ii）删除Sox 10的一个拷贝 来自内沟和外沟的非感觉细胞，和iii）缺失一个Sox 2拷贝加上一个Sox 10拷贝 来自Corti器官的支持细胞在这些基因操作之后，我们将研究 毛细胞样细胞的数量或成熟度是否提高。我们预计，我们的研究将 揭示了支持细胞网络基因作为听力恢复治疗靶点的独特作用。

Project Summary/Abstract The goal of this project is to investigate whether the loss of key supporting cell fate genes will enhance the reprogramming and regeneration of cochlear cells into hair cells as a strategy for hearing restoration. We have found that supporting cells of the mature cochlea can be reprogrammed into hair cell-like cells following combined damage AND reprogramming with Atoh1+Gfi1+Pou4f3. We have also found that non-sensory cells of the inner and outer sulcus can be reprogrammed with Atoh1+Gfi1+Pou4f3 and provide a second potential population of cells for hearing restoration. Here, we are targeting two Sox-family genes that regulate hair cell fate but are expressed in supporting cells and other non-sensory cells in the mature cochlea. Sox-family members Sox2 and Sox10 are both linked to hair cell fate decisions as they each produce ectopic hair cells when one allele is lost. Supporting cells nearest to the inner hair cells appear to be particularly susceptible to the combined loss of both Sox2 AND Sox10 in the production of ectopic inner hair cells. Moreover, preliminary data suggests that reprogrammed hair cell-like cells do not turn off Sox2 or Sox10 possibly limiting their complete fate conversion. Remarkably, the loss of one allele of Sox2 increases the number of regenerated hair cells suggesting that it is preventing hair cell fate in these cells. Here, we hypothesize that supporting cell network genes, Sox2 and Sox10, are restricting the cell’s ability to turn into a hair cell following reprograming. To test this hypothesis, we will use genetically modified mouse models to reprogram and regenerate cochlear cells into hair cell-like cells. In addition to reprogramming we will: i) completely delete Sox2 from cochlear supporting cells in the organ of Corti, ii) delete one copy of Sox10 from non-sensory cells of the inner and outer sulcus, and iii) delete one copy of Sox2 PLUS one copy of Sox10 from supporting cells in the organ of Corti. Following each of these genetic manipulations, we will investigate whether the number or the maturity of hair cell-like cells has improved. We anticipate that our studies will reveal a unique role for supporting cell network genes as a target for hearing restoration therapies.