CELL CYCLE IN OLIGODENDROCYTE DEVELOPMENT

描述：申请者S的目的是了解如何 少突胶质细胞的发育和髓鞘形成在中枢神经系统中受到调控， 旨在设计脱髓鞘障碍的治疗方法。Miskimins博士 提供的初步数据表明， 少突胶质细胞前体细胞伴随着明显的 细胞周期蛋白依赖性激酶抑制因子p27kip1(以及细胞周期蛋白E的降低)。她 提议增加p27kip1是发展和发展所必需的 少突胶质细胞的分化。具体来说，p27kip1的增加 可以解释分化前的增殖停止 并且还可以在分化程序的激活中发挥作用。 最初的目标是确定少突胶质细胞的特定阶段。 P27kip1水平升高的发育。在这项研究中，Miskimins博士将 利用少突胶质前体细胞(O-2A细胞)以及CG-4细胞 她报告说，这条线保留了O-2A细胞的许多属性。 另一组研究是定义增长因素和 已知的中度少突胶质细胞的信号分子(bFGF、TGFb和cAMP) P27kip1基因表达的研究进展申请者预测基本 成纤维细胞生长因子将干扰血管内皮生长因子的升高。 P27kip1，转化生长因子b和cAMP升高 P27kip1水平。在这些研究中，她将使用O-2A细胞和监测器 免疫荧光检测p27kip1在蛋白免疫印迹中的表达 Northern blotting。第三个目标是确定是否表达 P27kip1足以促进O-2A细胞的分化。构造 在可诱导启动子的控制下p27kip1的表达 转染CG-4细胞或增殖中的O-2A细胞。申请人 预测p27kip1的诱导将使增殖停止，并 促进差异化。将利用反义技术来确定 少突胶质细胞发育是否需要p27kip1。附录 提供的证据表明周期蛋白E的水平也应该被监测 并提出了这一点。

DESCRIPTION: The applicant s aim is to gain understanding of how oligodendrocyte development and myelination are regulated in the CNS, with a view to design therapies for demyelinating disorders. Dr. Miskimins presents preliminary data indicating that the differentiation of oligodendrocyte progenitor cells is accompanied by a marked increase in the cyclin dependent kinase inhibitor p27kip1 (and a decrease in cyclin E). She proposes that the increase in p27kip1 is necessary for development and differentiation of oligodendrocytes. Specifically, the increase in p27kip1 would account for the cessation of proliferation prior to differentiation and could also play a role in the activation of the differentiation program. An initial goal is to define the specific stage of oligodendrocytes development at which p27kip1 levels rise. For this study Dr. Miskimins will utilize the oligodendrocyte progenitor (O-2A cell), as well as the CG-4 cell line which she reports retains many of the properties of the O-2A cell. Another set of studies is to define the effects of growth factors and signaling molecules (bFGF, TGFB and cAMP) known to moderate oligodendrocyte development on the expression of p27kip1. The applicant predicts that basic fibroblasts growth factor (bFGF) will interfere with the elevation of p27kip1 while transforming growth factor b (TGF b) and cAMP should increase p27kip1 levels. For these studies she will utilize O-2A cells and monitor p27kip1 by immunofluorescence in Western blots and she will quantitate mRNA by Northern blotting. The third aim is to determine if expression of p27kip1 is sufficient to promote differentiation of O-2A cells. Constructs for expression of p27kip1 under the control of an inducible promoter will be transfected into either CG-4 or proliferating O-2A cells. The applicant predicts that induction of p27kip1 should bring proliferation to a halt and promote differentiation. Antisense technology will be utilized to determine if p27kip1 is required for oligodendrocyte development. An addendum provides evidence suggesting that cyclin E levels should also be monitored and this is proposed.