MACROMOLECULAR ARCHITECTURE OF THE SYNAPSE

突触的大分子结构

• 批准号: 6290677
• 负责人: Thomas S Reese
• 金额: --
• 依托单位: NATIONAL INSTITUTE OF NEUROLOGICAL DISORDERS AND STROKE
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6290677
• 关键词: actins; calmodulin dependent protein kinase; cell component structure /function; electron microscopy; freezing; glass; nerve /myelin protein; spectrin; structural biology; synapses

This new project analyzes the molecular architecture of synapses in the mammalian brain with an initial focus on the postsynaptic density (PSD). Many molecular components of the PSD are known, but the PSD is so large approximately 10 billion Dathat methods had to be developed to understand how its numerous molecular components are organized. A new approach begins by attaching PSDs to glass, labeling them with immunogold, and then freezing and replicating them for electron microscopy. Work to date reveals a lattice-like structure that forms the core of the PSD and labels heavily for PSD-95. Our current focus is on the enzyme CaMKII which is the major protein in forebrain PSDs. During stress, CaMKII forms aggregates in cell bodies and in spines collects on the cytoplasmic surface of the PSD, accounting for much of the thickening that occurs during stress. We have proposed that this ability to aggregate allows it to continue to buffer calmodulin while protecting the neuron from excessive phosphorylation. We are currently investigating the mechanism of CaMKII aggregation as well as what role it may have in normal neuronal function. As the distributions of functional components are determined we plan to develop a macromolecular architecture of the PSD - synapse, PSD, synaptic structure, PSD-95, NR-1, CaMKII, structural biology

这个新项目分析了哺乳动物大脑中突触的分子结构，最初的重点是突触后密度(PSD)。PSD的许多分子成分是已知的，但PSD是如此之大，大约100亿DAA，因此必须开发方法来了解其众多分子成分是如何组织的。一种新的方法开始于将PSD连接到玻璃上，用免疫金标记物，然后冷冻并复制它们用于电子显微镜。到目前为止的工作揭示了一种格子状结构，形成了PSD的核心，并为PSD-95贴上了沉重的标签。我们目前的重点是CaMKII酶，它是前脑PSD中的主要蛋白质。在应激过程中，CaMKII在细胞体中形成聚集体，在PSD的细胞质表面聚集在棘突中，这是应激过程中发生的大部分增厚的原因。我们提出，这种聚集的能力允许它继续缓冲钙调蛋白，同时保护神经元免受过度磷酸化的影响。我们目前正在研究CaMKII聚集的机制以及它在正常神经功能中可能起到的作用。随着功能成分分布的确定，我们计划建立PSD-突触、PSD、突触结构、PSD-95、NR-1、CaMKII、结构生物学的大分子体系