Francius Cédric, Hidalgo-Figueroa María, Debrulle Stéphanie, Pelosi Barbara, Rucchin Vincent, Ronellenfitch Kara, Panayiotou Elena, Makrides Neoklis, Misra Kamana, Harris Audrey, Hassani Hessameh, Schakman Olivier, Parras Carlos, Xiang Mengqing, Malas Stavros, Chow Robert L, Clotman Frédéric
Laboratory of Neural Differentiation, Institute of Neuroscience, Université catholique de Louvain Brussels, Belgium.
Department of Biology, University of Victoria Victoria, BC, Canada.
Front Mol Neurosci. 2016 Dec 26;9:145. doi: 10.3389/fnmol.2016.00145. eCollection 2016.
Spinal ventral interneurons regulate the activity of motor neurons, thereby controlling motor activities. Interneurons arise during embryonic development from distinct progenitor domains distributed orderly along the dorso-ventral axis of the neural tube. A single ventral progenitor population named p2 generates at least five V2 interneuron subsets. Whether the diversification of V2 precursors into multiple subsets occurs within the p2 progenitor domain or involves a later compartment of early-born V2 interneurons remains unsolved. Here, we provide evidence that the p2 domain produces an intermediate V2 precursor compartment characterized by the transient expression of the transcriptional repressor . These cells display an original repertoire of cellular markers distinct from that of any V2 interneuron population. They have exited the cell cycle but have not initiated neuronal differentiation. They coexpress and , suggesting that they can generate the known V2 interneuron populations as well as possible additional V2 subsets. Unlike V2 interneurons, the generation of Vsx1-positive precursors does not depend on the Notch signaling pathway but expression of in these cells requires Pax6. Hence, the p2 progenitor domain generates an intermediate V2 precursor compartment, characterized by the presence of the transcriptional repressor Vsx1, that contributes to V2 interneuron development.
脊髓腹侧中间神经元调节运动神经元的活动，从而控制运动行为。中间神经元在胚胎发育过程中起源于沿神经管背腹轴有序分布的不同祖细胞区域。一个名为p2的单一腹侧祖细胞群体产生至少五个V2中间神经元亚群。V2前体细胞分化为多个亚群是发生在p2祖细胞区域内，还是涉及早期产生的V2中间神经元的后期区室，这一问题仍未解决。在这里，我们提供证据表明，p2区域产生了一个中间V2前体细胞区室，其特征是转录抑制因子的瞬时表达。这些细胞展示了一套与任何V2中间神经元群体不同的独特细胞标志物。它们已经退出细胞周期，但尚未开始神经元分化。它们共表达 和 ，这表明它们可以产生已知的V2中间神经元群体以及可能的其他V2亚群。与V2中间神经元不同，Vsx1阳性前体细胞的产生不依赖于Notch信号通路，但这些细胞中 的表达需要Pax6。因此，p2祖细胞区域产生了一个中间V2前体细胞区室，其特征是存在转录抑制因子Vsx1，这有助于V2中间神经元的发育。
