Mechanisms of Prion Spread and Neuronal Toxicity

朊病毒传播和神经元毒性的机制

基本信息

批准号：
10587437
负责人：
Christina Sigurdson
金额：
$ 62.43万
依托单位：
UNIVERSITY OF CALIFORNIA, SAN DIEGO
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-02-01 至 2027-01-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10587437
关键词：
AMPA Receptors Acceleration Affect Alzheimer&apos s Disease Animal Model Automobile Driving Binding Binding Proteins Biochemical Biological Models Brain Cell Membrane Proteins Chronic Complex Creutzfeldt-Jakob Syndrome Critical Pathways Data Disease Disease Progression Dissection Electron Microscopy Electrophysiology (science)Endosomes Event Excision Functional disorder Funding Genes Glutamate Receptor Glutamates Goals Hippocampus Homeostasis Human Impairment In Vitro Infection Light Link Location Longitudinal Studies Mass Spectrum Analysis Membrane Membrane Proteins Modeling Multivesicular Body Mus Mutate Myoclonus N-Methyl-D-Aspartate Receptors Nerve Degeneration Neurodegenerative Disorders Neurons Outcome Pathologic Pathway interactions Patients Phosphorylation Phosphotransferases Physiological Postsynaptic Membrane PrP PrPSc Proteins Prion Diseases Prions Proteins Proteomics Reactive Oxygen Species Receptor Signaling Reporting Reproducibility STEM research Sampling Scaffolding Protein Signal Pathway Signal Transduction Sorting Spinal Cord Structure Synapses Synaptic Receptors Synaptic plasticity Synaptosomes Testing Time Transgenic Mice Ubiquitin Ubiquitination Up-Regulation abeta oligomer calmodulin-dependent protein kinase II conformer excitatory neuron excitotoxicity experimental study extracellular genetic manipulation in vivo insight microvesicles neuron loss neurotoxic neurotoxicity neurotransmission new therapeutic target phosphoproteomics postsynaptic presynaptic protein aggregation protein complex protein expression protein transport proteostasis receptor response synaptic function trafficking transcription factor

项目摘要

Synaptic dysfunction and neuritic dystrophy are prominent pathologic features of the prion- and Alzheimer’s disease-affected brain. Ubiquitinated protein inclusions are also commonly observed, providing strong evidence of impaired proteostatic pathways. Ubiquitination of cell membrane proteins and clearance through the ESCRT pathway (endosomal sorting complex required for transport) is critical to maintaining synaptic homeostasis. Here we will deeply investigate the ESCRT pathway contributions to disrupted synaptic homeostasis in prion disease. In prion-infected mice, we have found markedly reduced ESCRT-0 (an Hrs and STAM1 protein complex) and an enrichment of ubiquitinated proteins in synaptosomes. Strikingly, depleting neuronal Hrs in prion-infected mice shortened survival time and accelerated the degeneration of synapses, biochemically and structurally. Additionally, in a longitudinal study of the prion-infected hippocampus, we found an upregulation in the synaptic activity response gene, Arc/Arg3.1, and a chronic elevation in phosphorylated CaMKII and phosphorylated AMPA receptors, suggestive of enhanced and altered synapse function beginning in early disease. Our long-term goal is to decipher how prion and amyloid-β oligomers disrupt signaling pathways linked to the cellular prion protein, inducing proteostatic dysfunction and synaptic degeneration. Using electrophysiology, correlative light-electron microscopy, and proteomics on uninfected and prion-infected cultured neurons, we will first determine how Hrs expression impacts synapses, assessing activity, pre-and post-synaptic proteins, structure, and signaling. We will then test how distinct prion conformers impact the ESCRT pathway and neuronal signaling at glutamatergic synapses. Finally, we will investigate the contribution of glutamate receptor activity to prion spread and neurodegeneration. We will directly test how the findings in these genetically manipulated models compare to human prion-affected brain. These studies are the first to test how neuronal activity impacts prion dissemination, synaptic degeneration, and disease progression, and outcomes are expected to provide key insights into the deregulated synaptic signaling that drives neuron loss, thus revealing new therapeutic targets.

突触功能障碍和神经性营养不良是Prion和阿尔茨海默氏病影响的大脑。通常也观察到泛素化蛋白夹杂物，提供有力的蛋白质抑制途径的证据。细胞膜的泛素化通过ESCRT途径的蛋白质和清除率（内体分类复合物需要运输）对于维持突触稳态至关重要。在这里，我们将深入研究对prion病中突触稳态破坏的索引途径贡献。在原始感染的小鼠中，我们发现ESCRT-0显着降低（HRS和STAM1蛋白复合物）以及突触体中泛素化蛋白的富集。令人惊讶的是，耗尽神经元HRS 在原始的小鼠中，小鼠缩短了生存时间，并加速了突触的变性，生化和结构上。此外，在对原始感染的纵向研究中海马，我们发现突触活动反应基因，ARC/ARG3.1和磷酸化的CAMKII和磷酸化AMPA接收器的慢性升高，暗示性从早期疾病开始的突触功能增强和改变的突触功能。我们的长期目标是解释了prion和淀粉样蛋白-β低聚物如何破坏与细胞prion相关的信号通路蛋白质，诱导蛋白质抑制功能障碍和突触变性。使用电生理学，相关的光电子显微镜以及未感染和原始培养的蛋白质组学神经元，我们将首先确定HRS表达如何影响突触，评估活性，突触后蛋白，结构和信号传导。然后，我们将测试不同的prion 构象体影响谷氨酸能突触的ESCRT途径和神经元信号传导。最后，我们将调查谷氨酸接收器活动对主要差异和神经变性。我们将直接测试这些一般操纵模型中的发现如何与受人有关的大脑相比。这些研究是第一个测试神经元活性的研究影响王室传播，突触变性和疾病进展，结果是预计将对驱动神经元丧失的不受管制的突触信号提供关键见解，因此揭示了新的治疗靶标。