The Role of ERM Proteins in Axonal Development

描述（由申请人提供）：Ezrin， radixin和moesin，统称为ERM蛋白，作为膜相关分子和底层细胞骨架之间的连接物。最近，ERM蛋白ezrin与发育中重要的粘附分子L1之间的结合相互作用被发现。此外，在细胞培养模型中，ERM蛋白功能的破坏已被证明会影响轴突的生长。由于黏着分子的底物不能在体外重现，目前还不可能充分探索ERM蛋白通过与黏着分子和细胞骨架同时相互作用在轴突发育中的假定作用。在本提案的目的1中，粘附分子和erm之间相互作用的可行性，这与发育中的大脑皮层轴突发芽有关，将通过免疫组织化学和Western blotting进行测试。在Aim 2中，ERM显性阴性、构成性活性ERM和对照将在神经元中表达，其轴突通过子宫内基因转移投射到大脑皮层的中间区。对表达功能丧失、功能获得和控制结构的动物轴突发育标志物和形态学的比较显微镜分析将阐明ERM在轴突生长中的作用。对ERM功能的全面理解不仅有助于发育神经生物学的发展，而且有助于在中风、阿尔茨海默病和脊髓损伤等疾病的治疗中，通过发育重演进行轴突再生时可能需要的知识体系。

DESCRIPTION (provided by applicant): Ezrin, radixin, and moesin, collectively known as the ERM proteins, serve as linkers between the membrane associated molecules and the underlying cytoskeleton. Recently, a binding interaction between the ERM protein, ezrin, and the developmentally important adhesion molecule, L1, has been discovered. Furthermore, disruption of ERM protein function has been shown to affect axonal outgrowth in cell culture models. Because the substrate for adhesion molecules cannot be recapitulated in vitro, it is not currently possible to fully explore the putative role of ERM proteins, via their simultaneous interactions with adhesion molecules and the cytoskeleton, in axonal development. In Aim 1 of this proposal the plausibility of an interaction between adhesion molecules and ERMs, which is relevant to axonal sprouting in the developing cerebral cortex, will be tested with immunohistochemistry and Western blotting. In Aim 2, an ERM dominant negative, a constitutively active ERM, and controls will be expressed in neurons whose axons project into the intermediate zone of the cerebral cortex via in utero gene transfer. Comparative microscopic analysis of axonal development markers and morphology in animals expressing loss of function, gain of function, and control constructs will elucidate ERM function in axon outgrowth. A complete understanding of ERM function will contribute not only to developmental neurobiology, but also to the body of knowledge that will likely be needed if axonal regeneration by recapitulation of development is to be undertaken for therapeutic reasons in diseases such as stroke, Alzheimer's disease and spinal cord injury.