Tanabe Y, William C, Jessell T M
Howard Hughes Medical Institute, Department of Biochemistry and Molecular Biophysics, Columbia University, New York, New York 10032, USA.
Cell. 1998 Oct 2;95(1):67-80. doi: 10.1016/s0092-8674(00)81783-3.
Sonic hedgehog signaling controls the differentiation of motor neurons in the ventral neural tube, but the intervening steps are poorly understood. A differential screen of a cDNA library derived from a single Shh-induced motor neuron has identified a novel homeobox gene, MNR2, expressed by motor neuron progenitors and transiently by postmitotic motor neurons. The ectopic expression of MNR2 in neural cells initiates a program of somatic motor neuron differentiation characterized by the expression of homeodomain proteins, by neurotransmitter phenotype, and by axonal trajectory. Our results suggest that the Shh-mediated induction of a single transcription factor, MNR2, is sufficient to direct somatic motor neuron differentiation.
音猬因子信号通路控制着腹侧神经管中运动神经元的分化，但其中间步骤尚不清楚。对来自单个音猬因子诱导的运动神经元的cDNA文库进行差异筛选，鉴定出一个新的同源框基因MNR2，该基因由运动神经元祖细胞表达，并在有丝分裂后的运动神经元中短暂表达。MNR2在神经细胞中的异位表达启动了一个体运动神经元分化程序，其特征为同源结构域蛋白的表达、神经递质表型以及轴突轨迹。我们的结果表明，音猬因子介导的单一转录因子MNR2的诱导足以指导体运动神经元的分化。
