Extensive Supporting Cell Proliferation and Mitotic Hair Cell Generation by In Vivo Genetic Reprogramming in the Neonatal Mouse Cochlea
Extensive Supporting Cell Proliferation and Mitotic Hair Cell Generation by In Vivo Genetic Reprogramming in the Neonatal Mouse Cochlea
复制标题
新生小鼠耳蜗体内基因重编程的广泛支持细胞增殖和有丝分裂毛细胞生成
DOI：
10.1523/jneurosci.0060-16.2016
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发表时间：
2016-08-17
影响因子：
5.3
通讯作者：
Li, Huawei
中科院分区：
文献类型：
--
作者：
Ni, Wenli;Lin, Chen;Li, Huawei
从增殖支持细胞（SCs）分化生成毛细胞（HCs）似乎是替代耳蜗中丢失的HCs的理想方法，并有望在Corti器官损伤后恢复听力。我们在这里表明，在新生小鼠耳蜗Sox2+ SCs中，通过激活β-catenin上调Wnt信号，缺失Notch1下调Notch信号，以及过表达Atoh1的遗传重编程过程，实现了SCs的广泛增殖和有丝分裂HC的产生。我们使用RNA测序来比较Sox2+ SCs中对照组小鼠和β-catenin激活、Notch1缺失以及β-catenin激活合并Notch1缺失小鼠耳蜗的转录本。我们确定了参与增殖和转分化过程的基因，这些基因要么由单个信号通路控制，要么由Wnt和Notch信号通路的组合控制。此外，Notch1敲除Sox2+细胞后，Notch1缺失诱导的SCs增殖在删除β-catenin后消失，进一步证明Notch信号是Wnt信号的上游负调控因子。我们在这里表明，支持细胞（SCs）的广泛增殖和随后的有丝分裂毛细胞（HC）的产生是通过遗传重编程过程实现的，该过程涉及激活β-catenin以上调Wnt信号，缺失Notch1以下调Notch信号，以及Sox2+耳蜗中Atoh1的过表达。通过比较对照组、β-catenin激活组、Notch1缺失组和β-catenin激活组与Notch1缺失组耳蜗的转录本，我们发现了多个参与耳蜗增殖和转分化过程的基因，这些基因要么由单个信号通路控制，要么由Wnt和Notch信号通路联合控制。这为有丝分裂HC产生的机制提供了更好的理解，并可能为刺激有丝分裂HC再生提供新的方法。
The generation of hair cells (HCs) from the differentiation of proliferating supporting cells (SCs) appears to be an ideal approach for replacing lost HCs in the cochlea and is promising for restoring hearing after damage to the organ of Corti. We show here that extensive proliferation of SCs followed by mitotic HC generation is achieved through a genetic reprogramming process involving the activation of β-catenin to upregulate Wnt signaling, the deletion of Notch1 to downregulate Notch signaling, and the overexpression of Atoh1 in Sox2+ SCs in neonatal mouse cochleae. We used RNA sequencing to compare the transcripts of the cochleae from control mice and from mice with β-catenin activation, Notch1 deletion, and β-catenin activation combined with Notch1 deletion in Sox2+ SCs. We identified the genes involved in the proliferation and transdifferentiation process that are either controlled by individual signaling pathways or by the combination of Wnt and Notch signaling. Moreover, the proliferation of SCs induced by Notch1 deletion disappears after deleting β-catenin in Notch1 knock-out Sox2+ cells, which further demonstrates that Notch signaling is an upstream and negative regulator of Wnt signaling. SIGNIFICANCE STATEMENT We show here that the extensive proliferation of supporting cells (SCs) and the subsequent mitotic hair cell (HC) generation is achieved through a genetic reprogramming process involving activation of β-catenin to upregulate Wnt signaling, deletion of Notch1 to downregulate Notch signaling, and overexpression of Atoh1 in Sox2+ SCs in neonatal mice cochleae. By comparing the transcripts of the cochleae among controls, β-catenin activation, Notch1 deletion, and β-catenin activation combined with Notch1 deletion group, we identified multiple genes involved in the proliferation and transdifferentiation process that are either controlled by individual signaling pathways or by the combination of Wnt and Notch signaling. This provides a better understanding of the mechanisms behind mitotic HC generation and might provide new approaches to stimulating mitotic HC regeneration.