GLIAL MEMBRANES AT THE NODE OF RANVIER PREVENT NEURITE OUTGROWTH

这个子项目是利用由NIH/NCRR资助的中心拨款提供的资源的许多研究子项目之一。子项目和调查员(PI)可能从另一个NIH来源获得了主要资金，因此可能会出现在其他CRISE条目中。列出的机构是针对中心的，而不一定是针对调查员的机构。兰维尔结节是沿着有髓神经规则放置的无髓轴突节段。在这里，我们展示了从哺乳动物的中枢神经系统(CNS)分离的节膜限制了培养神经元的突起生长。对这些膜的蛋白质组学分析发现了几种抑制轴突生长的物质，包括少突胶质髓磷脂糖蛋白(OMGp)。在大鼠脊髓中，OMGp并不像以前认为的那样定位于致密的髓鞘，而是定位于少突胶质细胞样细胞，其突起会聚在一起形成一个完全包围结节的环。在OMGp基因缺失的小鼠中，中枢神经系统结节异常宽，并可观察到侧枝萌发。中枢神经系统内的结节被膜可稳定结节，防止轴突出芽。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Nodes of Ranvier are regularly placed, nonmyelinated axon segments along myelinated nerves. Here we show that nodal membranes isolated from the central nervous system (CNS) of mammals restricted neurite outgrowth of cultured neurons. Proteomic analysis of these membranes revealed several inhibitors of neurite outgrowth, including the oligodendrocyte myelin glycoprotein (OMgp). In rat spinal cord, OMgp was not localized to compact myelin, as previously thought, but to oligodendroglia-like cells, whose processes converge to form a ring that completely encircles the nodes. In OMgp-null mice, CNS nodes were abnormally wide and collateral sprouting was observed. Nodal ensheathment in the CNS may stabilize the node and prevent axonal sprouting.