PROTEOMIC MAPPING OF MYELIN AND ITS MEMBRANE SUBDOMAINS

描述(摘自申请者的摘要)：髓鞘是一种动态的、功能强大的 活性膜，对包括轴突在内的环境敏感。在.期间 髓鞘生成，它的产生数量惊人。它是一个极化的 膜，具有宏观和微观结构。它积极地维护 其独特的结构和与轴突的特殊关系。它的有趣之处在于 生化特性是高浓度的特定糖鞘糖脂， 尤其是半乳脑苷(GalC)和硫脂。半乳糖脂有 与少突胶质细胞分化的调节密切相关 和髓磷脂的维护。 与胆固醇相结合，目前的证据表明，这些脂质 能够形成微域，在微域中一组离散的蛋白质成为 为了实现通常与信号有关的专门功能而关联 转导。而相当少量的“主要”髓鞘蛋白是 认识到，在数量上识别不佳的“次要”过多。 蛋白质。人们对这两个类别的功能知之甚少。这一长期计划 这个应用程序的目标是开发一个总补充量的数据库 髓鞘蛋白的髓鞘蛋白质组，并开始与之结合的任务 与这些结构/代谢成分中的每一个一起发挥作用。 这将通过首先显示总的髓鞘蛋白来实现 补体作为二维凝胶电泳图，并鉴定 通过免疫标记、非埃德曼质谱学和 生物信息学。这些信息将为该项目提供一个数据库 对于髓鞘生物界来说。其次，将进行详细的分析。 在髓鞘的神经节苷脂-胆固醇微域的蛋白质中， 将它们与总的髓鞘蛋白质组联系起来。将对其进行研究 组织，并将检验一个假设，该假设提出存在一个 可区分微域的马赛克。第三，这些信息将被用来 研究这些微域的功能生物学。中的小鼠模型 哪种半乳糖脑苷脂和硫化物不会产生(CGT缺失小鼠) 将从其微域的角度进行分析。在此鼠标中， 兰维尔是改变的；我们提出的是这些分子之间的关联 形态变化，我们已经证明了一组离散的 具有神经节苷脂微域的蛋白质发生改变。最后，我们有 显示髓鞘-少突胶质细胞糖蛋白(MOG)分割成这些 微域及其成熟过程中的实验刺激 少突胶质细胞导致特异性酪氨酸快速磷酸化 蛋白质。这与抗OMOG介导的变态反应的关系 脑脊髓炎将被考虑。 预期从这些调查中得出的概念将有助于 更好地了解髓鞘的生物发生、维持和正常功能，并帮助 设计促进多发性骨髓瘤髓鞘稳定性和再髓鞘形成的范例 硬化症。

DESCRIPTION (From the Applicant's Abstract):Myelin is a dynamic, functionally active membrane, sensitive to its environment including axons. During myelinogenesis, it is produced in prodigious quantities. It is a polarized membrane, with both macro- and microdomain organization. It actively maintains its unique structure and special relationship with axons. Among its interesting biochemical properties is a high concentration of specific glycosphingolipids, in particular galactocerebroside (GalC) and sulfatide. The galactolipids have been strongly implicated in the regulation of oligodendrocyte differentiation and myelin maintenance. In combination with cholesterol, current evidence indicates that these lipids are able to form microdomains in which a discrete set of proteins become associated in order to effect specialized functions often related to signal transduction. While a rather small number of "major" myelin proteins are recognized, there is a plethora of poorly identified quantitatively "minor" proteins. The function of both classes is poorly understood. This long term goal of this application is to develop a data base of the total complement of myelin proteins the Myelin Proteome, and to begin the task of associating function with each of these structural/metabolic components. This will be accomplished by first displaying the total myelin protein complement as a two-dimensional gel electrophoretic map, and identifying the individual members by immunolabeling, non-Edman mass spectrometry, and bioinformatics. This information will provide a database both for this project and for the myelin biology community. Second, a detailed analysis will be made of the proteins in the glycosphinogolipid-cholesterol microdomains of myelin, relating them to the total myelin proteome. A study will be made of their organization, and a hypothesis will be tested that proposes that there is a mosaic of distinguishable microdomains. Third, this information will be used to investigate the functional biology of these microdomains. A mouse model in which galactosylcerebroside and sulfide are not produced (the CGT-null mouse) will be analyzed in terms of its microdomains. In this mouse the nodes of Ranvier are altered; in what we propose are the molecular correlates of these morphological changes, we have shown that the association of a discrete set of proteins with the glycosphinogolipid microdomains is altered. Finally, we have shown that myelin-oligodendrocyte glycoprotein (MOG) partitions into these microdomains, and the experimental stimulation its entry in maturing oligodendrocytes results in the rapid tyrosine phosphorylation of specific proteins. The relationship of this to antiOMOG mediated allergic encephalomyelitis will be considered. It is expected that concepts derived from these investigations will help to better understand myelin biogenesis, maintenance and normal function, and help to design paradigms to promote myelin stability and remyelination in multiple sclerosis.