Transcriptional control of oligodendrocyte differentiation and myelination

少突胶质细胞是见于中枢所有区域的髓鞘神经胶质细胞。 神经系统。少突胶质细胞的主要功能是形成髓鞘。 围绕轴突，以确保电信号的快速和忠实传输。 在发育过程中，少突胶质细胞前体细胞(OPC)必须经历一个 一系列的形态和分子变化才能完全 分化为成熟的髓鞘少突胶质细胞。差异化和 少突胶质细胞的髓鞘形成过程受转录的严格控制 各种因素。最近的研究表明，Sox10转录因子直接 刺激OPC分化和髓鞘基因表达。然而，OPC 分化受到其他转录因子(TF)的严格调控，包括 Nkx2.2、Opol1、Hes5和Id4均在未分化的OPC细胞中表达 在发育中的中枢神经系统中。而Nkx2.2和Otl1的功能是 促进OPC分化，Hes5和Id4作为OPC成熟的抑制因子。这个 四种调控因子在OL调控中的作用关系 分化还没有确定。在此应用程序中，我们假设 Nkx2.2通过抑制OPC的表达或功能间接促进OPC成熟 Hes5和Id4的同源性，但在促进OPC方面与Opol1具有协同作用 差异化。这些假设将在提案的前两个目标中得到检验。 最近的数据显示，Nkx2.2在分化的OL和 Nkx2.2在少突胶质细胞系中过表达抑制MBP基因表达， 增加了Nkx2.2转换其角色成为髓鞘抑制物的可能性 在成熟的骨肉瘤中进行基因表达以防止髓鞘产生过多。这 将在提案的第三个目标中审查可能性。最后，我们将测试 假设Sox10在成熟的OL中持续表达具有维持功能 髓鞘基因表达与髓鞘稳定性。Sox10和Sox10的相互作用 髓鞘细胞中的Nkx2.2可能是髓鞘微妙平衡的原因 生产和结构维护。 这条研究路线可以帮助我们理解控制 轴突髓鞘形成过程，并为分子的发展提供了见解 促进少突胶质细胞再生和再髓鞘形成的途径 脱髓鞘疾病。

Oligodendrocytes are myelinating glial cells found in all regions of the central nervous system. The major function of oligodendrocytes is to form myelin sheaths around axons to ensure the rapid and faithful transmission of electrical signals. During development, oligodendrocytes precursor cells (OPCs) have to go through a series of morphological and molecular changes before they become fully differentiated into mature myelinating oligodendrocytes. The differentiation and myelination processes of oligodendrocytes are tightly controlled by transcription factors. Recent studies have demonstrated that Sox10 transcription factor directly stimulates OPC differentiation and myelin gene expression. However, OPC differentiation is tightly regulated by other transcription factors (TFs) including Nkx2.2, Olig1, Hes5 and Id4, all of which are expressed in undifferentiated OPC cells in the developing central nervous system. While Nkx2.2 and Olig1 function to promote OPC differentiation, Hes5 and Id4 act as inhibitors of OPC maturation. The functional relationship of these four regulatory TFs in the control of OL differentiation has not been determined. In this application, we hypothesize that Nkx2.2 enhances OPC maturation indirectly by suppressing the expression or function of Hes5 and Id4, but functions synergistically with Olig1 in promoting OPC differentiation. These hypotheses will be tested in the first two aims of the proposal. Recent data showed that Nkx2.2 is rapidly down-regulated in differentiated OLs and over-expression of Nkx2.2 in oligodendrocyte cell line inhibits MBP gene expression, raising the possibility that Nkx2.2 switches its role to become a repressor of myelin gene expression in mature OLs to prevent excessive myelin production. This possibility will be examined in the third aim of the proposal. Finally, we will test the hypothesis that persistent expression of Sox10 in mature OLs functions to maintain myelin gene expression and myelin sheath stability. The interplay of Sox10 and Nkx2.2 in myelinating OL cells may be responsible for the delicate balance of myelin production and structural maintenance. This line of study could help us understand molecular pathways that control axonal myelination process and provide insights into the development of molecular approaches to stimulate oligodendrocyte regeneration and remyelination in demyelinating diseases.