Hirabayashi Yusuke, Gotoh Yukiko
Institute of Molecular and Cellular Biosciences, University of Tokyo, 1-1-1 Yayoi, Tokyo 113-0032, Japan.
Neurosci Res. 2005 Apr;51(4):331-6. doi: 10.1016/j.neures.2005.01.004.
Cortical neural precursor cells (NPCs) sequentially undergo expansion, neurogenic and gliogenic phases during development, although the underlying mechanisms are poorly understood. Recent studies have identified a number of extrinsic factors that regulate the fate of NPCs. For example, we have shown that Wnt signaling induces neuronal differentiation of NPCs in an instructive manner. Importantly, Wnt signaling does so in late stage (neurogenic phase) of NPCs but not in early stage (expansion phase) of NPCs. Instead, Wnt signaling promotes proliferation of early NPCs. Likewise, STAT3-activating ligands induce astrocytic differentiation in late (gliogenic phase) but not in early (expansion and neurogenic phases) NPCs. These stage-dependent responses of NPCs might play a central role in determining the timing of differentiation and the size of final population of each differentiated cell type.
皮质神经前体细胞（NPCs）在发育过程中依次经历扩增、神经发生和胶质发生阶段，尽管其潜在机制尚不清楚。最近的研究已经确定了许多调节NPCs命运的外在因素。例如，我们已经表明，Wnt信号以一种指导性方式诱导NPCs的神经元分化。重要的是，Wnt信号在NPCs的晚期（神经发生阶段）而非早期（扩增阶段）发挥此作用。相反，Wnt信号促进早期NPCs的增殖。同样，激活STAT3的配体在晚期（胶质发生阶段）而非早期（扩增和神经发生阶段）的NPCs中诱导星形胶质细胞分化。NPCs的这些阶段依赖性反应可能在决定分化时间和每种分化细胞类型的最终群体大小方面发挥核心作用。
