New cell biology tools to study myelin development, dynamics, and disease

项目总结/摘要 髓磷脂--神经元轴突周围的电绝缘体--在脊椎动物中是快速神经信号传递所必需的， 而在多发性硬化症等疾病中以及随后的损伤中，它的缺失会导致患者严重残疾。髓磷脂 作为被动电绝缘体的传统角色最近被重新想象为一个动态过程， 少突胶质细胞响应神经元活动而构建和重塑髓鞘，并代谢支持 它们形成髓鞘的神经元这些新发现开启了许多令人兴奋的新研究问题，例如： 少突胶质细胞如何调节其形态以调节传导速度或其他神经元功能， 在发育过程中或在成年中枢神经系统（CNS）？髓磷脂动力学在 高级脑功能和多发性硬化症以外的神经退行性疾病？一个根本性的差距 目前的知识在于了解少突胶质细胞生物学是如何在所有的背景下进行调节的， 发展、动力学和疾病。弥合这一知识差距需要建立创新的新工具， 突破了阻碍我们研究少突胶质细胞生物学的实验限制， vivo至今这项提案的目标是创建一个病毒（AAV）工具包，用于研究少突胶质细胞生物学 in vivo.该工具包将允许明亮，稀疏的标记和操作单个少突胶质细胞在神经元中。 小鼠中枢神经系统，这将使研究能够确定控制少突胶质细胞形态的机制 (Aim 1）。此外，该工具包将允许亚细胞靶向的报告或干扰，以功能上不同的 少突胶质细胞内的区域，包括髓鞘（Aim 2）。我们建议这个病毒细胞生物学工具包 将对髓鞘和更广泛的神经科学领域产生广泛的积极影响，通过：i）迅速加速 与传统的小鼠遗传学相比，从想法到发现的时间，ii）通过 “即插即用”模块化构造体系结构，iii）解锁可视化和/或干扰单个小鼠的能力 少突胶质细胞在体内，和iv）创造新的工具来研究功能不同的亚细胞结构， 髓鞘。通过这项研究，我们将创建和优化一个简单但功能强大的工具包，用于研究髓鞘细胞 在小鼠CNS中的体内生物学。我们希望这些工具能够迅速被该领域所采用， 令人兴奋的髓鞘研究新领域我们将把这些工具作为免费资源共享，从而最大限度地 它们的潜在影响揭示了髓鞘发育，动力学和疾病的新细胞生物学见解。

PROJECT SUMMARY/ABSTRACT Myelin—the electrical insulator around neuronal axons—is essential in vertebrates for rapid nerve signaling, and its loss in diseases like multiple sclerosis and following injury causes severe disability in patients. Myelin’s traditional role as a passive electrical insulator has recently been reimagined as a dynamic process, in which oligodendrocytes build and remodel myelin sheaths in response to neuronal activity, and metabolically support the neurons they myelinate. These new discoveries open up many exciting new research questions, such as: how do oligodendrocytes regulate their morphology to tune conduction velocity or other neuronal functions, during development or in the adult central nervous system (CNS)? What roles do myelin dynamics play in higher-order brain functions and in neurodegenerative diseases beyond multiple sclerosis? A fundamental gap in current knowledge lies in understanding how oligodendrocyte cell biology is regulated in all of the contexts of development, dynamics, and disease. Bridging this knowledge gap requires building innovative new tools to break through the experimental limitations that have hindered our ability to study oligodendrocyte cell biology in vivo thus far. The goal of this proposal is to create a viral (AAV) toolkit for studying oligodendrocyte cell biology in vivo. This toolkit will allow for bright, sparse labeling and manipulation of single oligodendrocytes in the mouse CNS, which will empower studies to determine the mechanisms controlling oligodendrocyte morphology (Aim 1). In addition, this toolkit will allow subcellular targeting of reporters or perturbants to functionally-distinct regions within oligodendrocytes, including myelin sheaths (Aim 2). We propose that this viral cell biology toolkit will have a broad positive impact across the myelin and broader neuroscience fields, by: i) rapidly accelerating the time from idea to discovery, compared to traditional mouse genetics, ii) simplifying experimental design via “plug-and-play” modular construct architecture, iii) unlocking the ability to visualize and/or perturb single mouse oligodendrocytes in vivo, and iv) creating new tools to study functionally distinct subcellular structures in myelin. From this research, we will create and optimize a simple but powerful toolkit for studying myelin cell biology in vivo in the mouse CNS. It is our hope that these tools can be rapidly adopted by the field, and open exciting new frontiers in myelin research. We will share these tools as a free resource, thereby maximizing their potential impact to reveal new cell biological insights into myelin development, dynamics, and disease.