Membrane Remodeling by Arc/Arg3.1

Arc/Arg3.1 膜重塑

基本信息

批准号：
9889184
负责人：
JOSEPH P ALBANESI
金额：
$ 18.71万
依托单位：
UNIVERSITY OF HAWAII AT MANOA
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-03-15 至 2022-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9889184
关键词：
AMPA Receptors Adaptor Signaling Protein Alzheimer&apos s Disease Angelman Syndrome Binding Biological Assay C-terminal Capsid Cell membrane Cells Clathrin Adaptors Cognition Disorders Crystallization Cytoskeleton Data Dendritic Spines Docking Drug Addiction Dynamin Elements Endocytosis Extracellular Space Fluorescence Fragile X Syndrome Goals Guanosine Triphosphate Phosphohydrolases HIV Immediate-Early Genes Impairment Laboratories Learning Link Lipids Long-Term Depression Long-Term Potentiation Mediating Membrane Memory Mental Retardation Messenger RNA Modification Monitor Morphology Mus N-terminal Neurons Phase Phosphorylation Play Post-Translational Protein Processing Process Proteins Regulation Reporting Role Scheme Schizophrenia Spectrum Analysis Structure Substance abuse problem Surface Synapses Synaptic plasticity Taste Perception Testing Therapeutic Intervention Translating Vesicle Viral Virus Assembly Virus-like particle alpha helix base clinically significant cofactor experience experimental study extracellular vesicles fear memory fluidity gene product intercellular communication interest long term memory new therapeutic target overexpression palmitoylation particle self assembly unilamellar vesicle vesicular release

项目摘要

The activity-regulated cytoskeletal-associated protein (Arc, also known as Arg3.1) is an immediate early gene product induced by activity/experience and required multiple modes of synaptic plasticity. Both long-term potentiation (LTP) and long-term depression (LTD) are impaired upon Arc deletion, as well as the ability to form long-term spatial, taste and fear memories. The best-characterized function of Arc is enhancement of the endocytic internalization of AMPA receptors (AMPARs) in dendritic spines, a process associated with LTD. This role for Arc in AMPAR endocytosis was supported by a report that Arc binds directly to two elements of the endocytic machinery, dynamin and endophilin, and by our finding that Arc stimulates dynamin self-assembly and GTPase activity. Solution of the crystal structure of a C-terminal segment of Arc revealed a striking similarity to the capsid domain of HIV Gag. Moreover, Arc assembles into viral capsid-like structures that enclose Arc mRNA, are released into the extracellular space, and are internalized by neighboring cells. Thus, Arc is unique in promoting plasma membrane budding both into and out of the cell. The goal of this project is to define the mechanism and regulation of Arc-mediated membrane vesiculation. Fluorescence fluctuation spectroscopy (FFS) will be utilized to monitor membrane budding giant unilamellar vesicles (GUVs). In Aim 1 we will use spectral phasor analysis to determine how lipid composition and fluidity influence the budding process, and Number and Brightness (N&B) analysis to obtain a quantitative picture of Arc self-assembly on the GUV surface. In Aim 2 we will determine how post-translational modifications of Arc, recently identified in our laboratories, control the binding of Arc to lipids and mRNA and Arc-mediated membrane vesiculation. Changes in Arc expression have been linked to numerous cognitive disorders, including mental retardation, Alzheimer's Disease, and substance abuse. Therefore, elucidation of mechanisms that regulate Arc-mediated intercellular communication has potential clinical significance.

活性调节的细胞骨架相关蛋白（ARC，也称为arg3.1）是直接的早期基因由活动/经验引起的产品，需要多种突触可塑性。长期增强（LTP）和长期抑郁症（LTD）在弧缺失时受到损害，以及形成的能力长期的空间，品味和恐惧记忆。弧的最佳特征功能是增强树突状棘中AMPA受体（AMPARS）的内吞内在化，这是与Ltd相关的过程。这 ARC在AMPAR内吞作用中的作用得到了一份报告直接与两个元素结合的报道内吞机械，动力蛋白和内po蛋白，并且通过我们的发现刺激了dynamin自组装和 GTPase活性。弧的C末端片段的晶体结构的溶液显示出与艾滋病毒堵嘴的衣壳域。此外，弧聚集成围绕弧mRNA的病毒带囊状结构，被释放到细胞外空间中，并被相邻细胞内化。因此，ARC在促进质膜从细胞中和外出来。该项目的目的是定义弧介导的膜囊泡的机理和调节。荧光波动光谱（FFS）将用于监测膜萌芽的巨型Unilamelar囊泡（GUVS）。在AIM 1中，我们将使用光谱量相分析，以确定脂质组成和流动性如何影响发芽过程，以及数字和亮度（N＆B）分析以获得GUV表面上的ARC自组装的定量图片。在AIM 2中，我们将确定最近在我们的实验室中确定的弧后的翻译后修饰，如何控制弧与脂质和mRNA和弧介导的膜囊泡的结合。弧的变化表达与多种认知障碍有关，包括智力低下，阿尔茨海默氏病，和药物滥用。因此，阐明调节弧介导的细胞间的机制沟通具有潜在的临床意义。