Tateno M, Ukai W, Hashimoto E, Ikeda H, Saito T
Department of Neuropsychiatry, Sapporo Medical University, School of Medicine, Sapporo, Japan.
J Neural Transm (Vienna). 2006 Mar;113(3):283-93. doi: 10.1007/s00702-005-0320-6. Epub 2005 Jun 15.
The neuron-restrictive silencer factor (NRSF), or repressor element-1 silencing transcription factor (REST), is a transcription factor that mediates negative regulation of neuronal genes. NRSF represses multiple neuronal target genes in non-neuronal and neuronal precursor cells to regulate the proper timing of neuronal gene expression during neurogenesis. In the present study, we investigated the effects of ethanol and MEK inhibitor U0126 on the DNA binding activity of NRSF in neural stem cells prepared from rat embryos. Both ethanol and U0126 enhanced NRSF binding activity measured by the method based on the principal of electrophoretic mobility shift assay (EMSA) and decreased neuronal differentiation in a concentration dependent manner. Western blot analysis revealed that ethanol suppressed phosphorylation of extracellular signal-regulated kinase (ERK) without affecting expression of total ERK. These results suggest that ethanol-induced potentiation of NRSF binding activity underlies the mechanism of ethanol inhibition of neuronal differentiation and decreased neurogenesis.
神经元限制性沉默因子（NRSF），即阻遏元件1沉默转录因子（REST），是一种介导神经元基因负调控的转录因子。NRSF在非神经元细胞和神经元前体细胞中抑制多个神经元靶基因，以在神经发生过程中调节神经元基因表达的适当时间。在本研究中，我们研究了乙醇和MEK抑制剂U0126对从大鼠胚胎制备的神经干细胞中NRSF的DNA结合活性的影响。乙醇和U0126均通过基于电泳迁移率变动分析（EMSA）原理的方法增强了NRSF结合活性，并以浓度依赖性方式降低了神经元分化。蛋白质免疫印迹分析显示，乙醇抑制细胞外信号调节激酶（ERK）的磷酸化，而不影响总ERK的表达。这些结果表明，乙醇诱导的NRSF结合活性增强是乙醇抑制神经元分化和减少神经发生机制的基础。
