Investigating the mechanisms of Arc-dependent synaptic plasticity

研究弧依赖性突触可塑性的机制

• 批准号: 10171420
• 负责人: Jason D Shepherd
• 金额: $ 38.13万
• 依托单位: UNIVERSITY OF UTAH
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-06-05 至 2022-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10171420
• 关键词: 3-Dimensional; Adaptor Signaling Protein; Binding; Brain; Brain-Derived Neurotrophic Factor; Cell model; Cells; Clathrin; Clathrin Adaptors; Complex; DLG4 gene; Data; Deletion Mutation; Disease; Endocytosis; Endosomes; Evoked Potentials; Excision; Excitatory Synapse; Exocytosis; Functional disorder; Gap Junctions; Glutamate Receptor; Goals; Homeostasis; Human; Image; Imaging Techniques; Immediate-Early Genes; In Vitro; Individual; Knock-out; Learning; Light; Link; Lipid Binding; Lipids; Long-Term Potentiation; Maintenance; Mediating; Mediator of activation protein; Membrane; Membrane Proteins; Memory; Mental Depression; Mental disorders; Modeling; Molecular; Movement; Mus; Mutate; Nature; Neurodegenerative Disorders; Neurodevelopmental Disorder; Neurons; Pathway interactions; Patients; Point Mutation; Postsynaptic Membrane; Process; Protein Biosynthesis; Proteins; Proteomics; Recycling; Research; Resolution; Role; Scaffolding Protein; Site; Structure; Synapses; Synaptic Vesicles; Synaptic plasticity; Testing; Visual Cortex; Work; base; density; enhancer-binding protein AP-2; experimental study; fluorescence imaging; in vivo; insight; light microscopy; link protein; member; mutant; nanometer; nervous system disorder; novel; overexpression; postsynaptic; postsynaptic density protein; presynaptic; protein complex; protein function; protein protein interaction; protein transport; receptor; recruit; scaffold; stargazin; synaptic function; trafficking

The overarching goal of this proposal is to characterize the protein machinery that mediates trafficking of postsynaptic membrane proteins critical for synaptic plasticity. Endo- and exocytosis of membrane proteins are critical trafficking steps in all cells, but are especially dynamic and finely tuned in neurons. Unlike presynaptic endocytosis and synaptic vesicle recycling, the precise molecular processes that underlie postsynaptic trafficking still remain poorly defined. Little is known about how specific receptors are removed from the protein scaffolding complex at the postsynaptic density (PSD) or the functional role of protein-protein interactions within the PSD during synaptic plasticity. Our previous work identified the immediate early gene Arc as a critical mediator of memory storage in the brain and showed that Arc regulates AMPA-type glutamate receptor trafficking. We conducted unbiased proteomic screens and discovered novel Arc interacting proteins. Based on these screens, we hypothesize that Arc acts as a novel postsynaptic clathrin adaptor protein. Based on this hypothesis, we will test whether Arc binds lipids, recruits cargo to endosomes (e.g. AMPARs) and interacts with PSD proteins to release receptors from their scaffolding within the PSD. To study protein trafficking within nanodomains of synapses we have developed a novel live super-resolution light microscopy approach. This study will provide mechanistic insight into how Arc mediates multiple forms of synaptic plasticity and also broadly elucidates the protein machinery that is involved in postsynaptic trafficking of membrane proteins at excitatory synapses. Arc lies at a critical nexus as a critical synaptic effector protein and has been implicated in neurological and psychiatric disorders in human patients. Thus, this work will also shed light on synaptic dysfunction associated with neurological diseases.

该提案的总体目标是表征介导贩运的蛋白质机制。 突触后膜蛋白对突触可塑性至关重要。膜蛋白的胞内和胞吐作用是 所有细胞中的关键运输步骤，但在神经元中特别动态和精细调整。不像突触前 内吞作用和突触囊泡再循环，突触后的精确分子过程， 对贩运的定义仍然很模糊。对于特定受体如何从蛋白质中移除， 突触后密度（PSD）处的支架复合物或蛋白质-蛋白质相互作用的功能作用 在突触可塑性的PSD内。我们以前的工作确定了即时早期基因Arc作为一个 Arc是大脑中记忆储存的关键介质，并显示Arc调节AMPA型谷氨酸受体 贩卖人口我们进行了公正的蛋白质组学筛选，发现了新的Arc相互作用蛋白。基于 通过这些筛选，我们假设Arc是一种新的突触后网格蛋白衔接蛋白。基于此 假设，我们将测试Arc是否结合脂质，招募货物到内体（例如AMPAR），并相互作用 与PSD蛋白质结合以从PSD内的支架释放受体。为了研究蛋白质运输， 我们已经开发了一种新的活的超分辨率光学显微镜方法。这 这项研究将为Arc如何介导多种形式的突触可塑性提供机理上的见解， 广泛阐明了蛋白质机制，参与突触后膜蛋白的运输， 兴奋性突触Arc作为一种关键的突触效应蛋白，位于一个关键的连接点， 在人类患者中的神经和精神障碍。因此，这项工作也将阐明突触 与神经系统疾病相关的功能障碍。