Internal Dynamics of the Postsynaptic Density

突触后密度的内部动力学

基本信息

批准号：
10517494
负责人：
Thomas A Blanpied
金额：
$ 68.12万
依托单位：
UNIVERSITY OF MARYLAND BALTIMORE
依托单位国家：
美国
项目类别：
财政年份：
2007
资助国家：
美国
起止时间：
2007-04-05 至 2024-10-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10517494
关键词：
AMPA Receptors Actins Action Potentials Acute Address Adhesions Alzheimer&apos s Disease Architecture Behavior Binding Biological Brain Cell Adhesion Molecules Cells Complex Cytoskeleton Data Disease Electroporation Elements Event Evoked Potentials Extracellular Domain Face Funding Genetic Glutamate Receptor Glutamates Goals Grant Human Individual Knock-out Light Link Maintenance Maps Mediating Memory Mental Depression Mental disorders Methodology Methods Modeling Molecular Movement Nanostructures Neurons Neurosciences Optics Outcome Pattern Peptide Hydrolases Performance Physiological Physiology Play Polymers Positioning Attribute Probability Process Proteins Publishing Reagent Resolution Role Sampling Scaffolding Protein Schizophrenia Signal Transduction Site Slice Structure Synapses Synaptic Cleft Synaptic Potentials Synaptic Receptors Synaptic Transmission Synaptic plasticity Technology Testing Time Vesicle Visualization Work addiction autism spectrum disorder biochemical tools brain tissue density depolymerization experience experimental study extracellular genetic regulatory protein imaging modality in utero in vivo insight molecular imaging nano nanocluster nanometer resolution nanopattern nanoscale neuroligin 1 neurotransmitter release pharmacologic polymerization postsynaptic presynaptic protein complex receptor recruit single molecule spatiotemporal superresolution imaging synaptic function tool

项目摘要

Mechanisms that create, maintain, and modulate synapses are essential building blocks of human behavior. Disruptions to these mechanisms are inextricably linked to aberrant behavior and diseases ranging from depression and schizophrenia to addiction and Alzheimer’s Disease. Thus, the long-term goal of this grant is to pursue a deep understanding of the molecular organization underlying synaptic transmission and plasticity. Our previous work took advantage of the extremely high-resolution enabled by single-molecule imaging methods and determined that at glutamatergic synapses, key proteins in the active zone and the postsynaptic density are enriched in subsynaptic nanodomains (<100 nm). Most surprisingly, nanodomains of the critical fusion-regulatory proteins RIM and Munc13 in the presynaptic active zone align with high precision across the synaptic cleft from nanodomains enriched in postsynaptic glutamate receptors. Using single-vesicle fusion mapping, we determined that the local density of RIM within active zone subregions predicts the probability of action potential-evoked vesicle fusion. This striking architectural arrangement has important implications for how synapses function. This nano-alignment between release sites and receptors can modulate synaptic transmission and potentially influence intracellular signaling. Preliminary data here and published work from others establishes that transsynaptic nanoalignment is an important element of synaptic architecture, widely present in diverse synapse types. Further, our data provide firm evidence that subsynaptic nanostructure and nanoalignment are dynamically modulated during synaptic plasticity and actively maintained by ongoing molecular interactions. These observations strongly motivate understanding the mechanisms involved in creating and maintaining transsynaptic alignment. Therefore, we will test a set of related but independent hypotheses about the origin and maintenance of transsynaptic nanoalignment. We will test 1) whether two key neurexin partners, neuroligin and LRRTM, cooperate to provide the structural basis of transsynaptic alignment, 2) whether glutamate receptors themselves are necessary or sufficient to influence the nanoscale protein organization of the active zone 3), whether the active zone RIM complex conveys instructive information to establish postsynaptic nanopatterning, and 4) how the actin cytoskeleton exerts ongoing control over synapse nanoscale architecture. To answer these questions, we have worked to establish and apply several new broadly useful technologies. We utilize a new super-resolution imaging methodology to visualize cellular substructure at nanometer resolution in vivo, apply multiplexed single-molecule imaging to map numerous proteins in the same sample, and develop new optical and biochemical tools to acutely control the actin cytoskeleton, adhesion complexes, and receptor distribution with high spatiotemporal resolution and in brain slices. The outcomes of these experiments will answer core questions about the genesis of an important new aspect of synaptic architecture and test the physiological role of synaptic nanoalignment in brain circuits.

创建、维持和调节突触的机制是人类行为的重要组成部分。这些机制的破坏与异常行为和疾病有着千丝万缕的联系：因此，这笔赠款的长期目标是追求对突触传递和可塑性背后的分子组织的深入理解。我们之前的工作利用了单分子成像的极高分辨率方法并确定在谷氨酸能突触中，活性区和突触后的关键蛋白质最令人惊讶的是，突触下纳米域（<100 nm）的密度丰富。突触前活性区的融合调节蛋白 RIM 和 Munc13 在整个突触区高精度对齐使用单囊泡融合从富含突触后谷氨酸受体的纳米结构域中分离突触间隙。通过映射，我们确定活动区子区域内 RIM 的局部密度可以预测这种引人注目的结构排列对于动作电位诱发的囊泡融合具有重要意义。突触如何发挥作用。释放位点和受体之间的纳米排列可以调节突触。传输并可能影响细胞内信号传导。这里的初步数据和已发表的工作。其他人确定跨突触纳米排列是突触结构的重要元素，广泛应用于此外，我们的数据提供了确凿的证据，表明突触下纳米结构和纳米排列在突触可塑性过程中动态调节，并通过持续的过程积极维持这些观察强烈激发了我们对分子相互作用的理解。因此，我们将测试一组相关但独立的突触对齐。关于突触纳米排列的起源和维持的假设我们将测试 1）是否有两个关键。 neurexin 合作伙伴，neuroligin 和 LRRTM，合作提供跨突触排列的结构基础， 2）谷氨酸受体本身对于影响纳米级蛋白质是否是必要的或充分的活动区 3) 的组织，活动区 RIM 复合体是否向建立突触后纳米图案，4) 肌动蛋白细胞骨架如何对突触发挥持续控制为了回答这些问题，我们致力于建立并应用几种新的结构。我们利用一种新的超分辨率成像方法来可视化细胞。体内纳米分辨率的子结构，应用多重单分子成像来绘制大量同一样品中的蛋白质，并开发新的光学和生化工具来精确控制肌动蛋白大脑中具有高时空分辨率的细胞骨架、粘附复合物和受体分布这些实验的结果将回答有关重要新事物起源的核心问题。突触结构的方面并测试突触纳米排列在脑回路中的生理作用。