MACROMOLECULAR ARCHITECTURE OF THE SYNAPSE

这个新项目分析了分子结构 哺乳动物大脑中的突触，最初的重点是 突触后密度（PSD）。许多分子成分 PSD 是众所周知的，但是 PSD 非常巨大（大约 10 到 第九大）必须开发新方法来理解 它的众多分子成分是如何组织的。一个 有前途的新方法首先将 PSD 附着到玻璃上，然后 然后冷冻并复制它们以进行电子显微镜检查。 释放之前的操作允许识别和定位 的特定组件。其中包括： PSD 的方向 通过用一种抗体预先处理玻璃来在玻璃上 它们的表面成分； PSD 的部分消化 带有清洁剂的玻璃；和标签，在上述任一之后 胶体金标记的抗体。迄今为止的工作清晰 区分 PSD 的裂边，其中 NR-1 和 PSD-95 是从 CaMKII 定位的细胞质侧定位的。 裂口的消化揭示了一种格子状结构，形成 PSD的核心；这个格子对 PSD-95 有很大的标签。的 血影蛋白和肌动蛋白与 PSD 的分布目前正在 研究的主题是 CaMKII 的分布 另一个项目。现在可以看出，空间分布 PSD 的组成部分是 PSD 功能的一个重要方面。

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 enormous (approximately 10 to the ninth Da) that new methods had to be developed to understand how its numerous molecular components are organized. A promising new approach begins by attaching PSDs to glass and then freezing and replicating them for electron microscopy. Manipulations prior to freeing allow identification and localization of particular components. These include: orientation of the PSDs on the glass by prior treatment of the glass with antibodies to one of their surface components; partial digestion of the PSDs on the glass with detergents; and labelling, after either of the above with antibodies marked by colloidal gold. Work to date clearly distinguishes the cleft side of the PSD, where NR-1 and PSD-95 are localized, from the cytoplasmic side where CaMKII is localized. Digestion of the cleft side reveals a lattice-like structure that forms the core of the PSD; this lattice labels heavily for PSD-95. The distributions of spectrin and actin with the PSD are currently being investigated, and the distribution of CaMKII is the subject of another project. It is now apparent that the spatial distributions of components of the PSD are an important aspect of PSD function.