Hatakeyama Jun, Sakamoto Susumu, Kageyama Ryoichiro
Institute for Virus Research, Kyoto University, Kyoto, Japan.
Dev Neurosci. 2006;28(1-2):92-101. doi: 10.1159/000090756.
The basic helix-loop-helix genes Hes1 and Hes5, known Notch effectors, regulate the maintenance of neural stem cells and the development of the central nervous system (CNS). In the absence of Hes1 and Hes5, the size, shape and cytoarchitecture of the CNS are severely disorganized, but the development of the peripheral nervous system remains to be analyzed. Here, we found that in Hes1;Hes5 double-mutant mice, the cranial and spinal nerve systems are also severely disorganized. In these mutant mice, axonal projections from the mesencephalic neurons to the trigeminal (V) ganglion become aberrant and the proximal parts of the glossopharyngeal (IX) and vagus (X) nerves are fused. The hypoglossal (XII) nerve is also formed poorly. Furthermore, the dorsal root ganglia are fused with the spinal cord, and the dorsal and ventral roots of the spinal nerves are lacking in many segments. These results indicate that Hes1 and Hes5 play an important role in the formation of the cranial and spinal nerve systems.
已知Notch效应因子的碱性螺旋-环-螺旋基因Hes1和Hes5调节神经干细胞的维持以及中枢神经系统（CNS）的发育。在缺乏Hes1和Hes5的情况下，CNS的大小、形状和细胞结构严重紊乱，但外周神经系统的发育仍有待分析。在此，我们发现，在Hes1;Hes5双突变小鼠中，颅神经和脊髓神经系统也严重紊乱。在这些突变小鼠中，从中脑神经元到三叉神经（V）节的轴突投射变得异常，舌咽神经（IX）和迷走神经（X）的近端部分融合。舌下神经（XII）也发育不良。此外，背根神经节与脊髓融合，脊髓神经的背根和腹根在许多节段中缺失。这些结果表明，Hes1和Hes5在颅神经和脊髓神经系统的形成中起重要作用。
