Viral tools for studying NG2 cells

描述(申请人提供)：少突胶质细胞，即中枢神经系统的髓鞘形成细胞，由已鉴定的前体细胞发展而来，也称为少突胶质前体细胞(OPC)、多树突状细胞或NG2细胞。这些细胞出现在啮齿类动物的中期，在发育中的中枢神经系统中的特定位置，广泛迁移，在迁移过程中增殖，然后缓慢分化为髓鞘形成细胞。令人惊讶的是，很大一部分OPC群体未能完全分化，并作为一种缓慢分裂的细胞持续存在于成年中枢神经系统，可以被认为是第四种神经胶质细胞类型。这些成年OPC的功能还不是很清楚，部分原因是它们不寻常地混合了神经胶质和神经元的特性。主要问题包括：1)这些细胞在发育中和成年动物中以及损伤后的表型可塑性；2)电兴奋性在OPC发育和功能中的作用。这项提议的目标是开发新的基于病毒的工具，用于分析NG2 OPC的发展和特性。我们的策略利用了细胞类型特定的可诱导cre小鼠驱动系的可用性，以及最近开发的“翻转”载体，在这些载体中串联突变的loxP位点允许将选定的基因从反义方向反转到正义方向。这一策略允许在时间上控制标记抗原、功能蛋白和RNAi的表达。这里将要开发的工具可以广泛用于研究中枢和外周神经系统内的其他胶质细胞类型。 公共卫生相关性：少突胶质细胞，即中枢神经系统的髓鞘形成细胞，从一种已鉴定的前体细胞发展而来，该前体细胞具有神经元和神经胶质属性的不同寻常的混合。它们在中枢神经系统内稳态中的功能作用(S)尚不清楚。将在这里开发的新工具将帮助我们了解这些细胞的不寻常属性，以及这些属性如何与这些细胞对损伤和脱髓鞘的反应有关。

DESCRIPTION (provided by applicant): Oligodendrocytes, the myelin forming cells of the CNS, develop from identified precursor cells known alternately as oligodendrocyte progenitor cells (OPCs), polydendrocytes, or NG2 cells. These cells appear about midgestation in rodents at specific locations within the developing CNS, migrate extensively, proliferate as they migrate, and then slowly differentiate into myelin-forming cells. Surprisingly, a large fraction of the OPC population fails to fully differentiate and persists throughout the adult CNS as a slowly dividing cell that can be considered an fourth glial cell type. The functions of these adult OPCs are not well understood, in part, because of their unusual mixture of glial and neuronal properties. Major questions remain regarding 1) the phenotypic plasticity of these cells in developing and adult animals and after injury and 2) the role of electrical excitability in OPC development and function. The goal of this proposal is to develop new viral-based tools for analyzing the development and properties of NG2+ OPCs. Our strategy takes advantage of the availability of cell-type specific inducible cre mouse driver lines and recently developed "flip" vectors in which tandem mutant loxP sites allow for inversion of selected genes from an anti-sense to sense orientation. This strategy allows for temporal control of the expression of marker antigens, functional proteins and RNAi. The tools to be developed here can be used widely to study other glial cell types within the central and peripheral nervous system. PUBLIC HEALTH RELEVANCE: Oligodendrocytes, the myelin-forming cells of the CNS, develop from an identified precursor cell that has an unusual mixture of neuronal and glial properties. Their functional role(s) in CNS homeostasis is unknown. The new tools to be developed here will help us to understand the unusual properties of these cells and how those properties relate to the responses of these cells to injury and demyelination.