Combining electron and nuclear magnetic resonance to track Alzheimer's amyloid-beta oligomer-to-fibril conversion

结合电子和核磁共振来追踪阿尔茨海默病β淀粉样蛋白寡聚物到原纤维的转化

• 批准号: 10662904
• 负责人: Zhefeng Guo
• 金额: $ 23.88万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-04-15 至 2025-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10662904
• 关键词: Adopted; Aliquot; Alzheimer' s Disease; Alzheimer' s disease brain; Alzheimer' s disease patient; Amyloid Fibrils; Amyloid beta-42; Amyloid beta-Protein; Antibodies; Binding; Brain; Calcium; Cell Nucleus; Dependence; Detergents; Dissociation; Electron Spin Resonance Spectroscopy; Electrons; Event; Fluorescence; Goals; Hippocampus; Impairment; In Vitro; Incubated; Isotopes; Kinetics; Label; Laboratories; Lead; Lipid Bilayers; Lipids; Liposomes; Long-Term Potentiation; Measurement; Measures; Mitochondria; Molecular Conformation; Monitor; Movement; Neurons; Nuclear Magnetic Resonance; Pathogenesis; Pathologic; Pathologic Processes; Phosphorylcholine; Play; Positioning Attribute; Procedures; Process; Proteins; Public Health; Ramp; Resolution; Role; Sampling; Signal Transduction; Slice; Stains; Structure; Synapses; System; Temperature; Testing; Therapeutic Intervention; Time; Transgenic Mice; Transmission Electron Microscopy; Vesicle; Water; Width; abeta accumulation; abeta oligomer; beta pleated sheet; conformational conversion; design; experimental study; insight; interest; monomer; presynaptic; real time monitoring; solid state nuclear magnetic resonance; success; tau Proteins

Project Summary/Abstract Aggregation of Aβ protein plays a central role in the pathogenesis of Alzheimer's disease. Aβ aggregation leads to the formation of soluble oligomers and insoluble fibrils. While amyloid fibrils are the main component of parenchymal plaques in Alzheimer's disease brains, the Aβ oligomers have been widely regarded as more toxic and more pathologically relevant. There is strong evidence supporting that at least some types of Aβ oligomers can undergo a conformational conversion to form fibrils. It is yet poorly understood how the oligomers could re-arrange their structures to form fibrils. In this proposed project, we will use a combination of electron and nuclear magnetic resonance to monitor structural changes during Aβ42 oligomer-to-fibril conversion. The Aβ42 oligomers will be prepared in the presence of low concentrations of detergent. These Aβ42 oligomers represent a type of stable oligomers, which convert to fibrils only in the presence of lipid vesicles. The oligomer-to-fibril conversion will be followed by performing EPR and NMR experiments at different time points. This study will provide insights into whether oligomers dissociate to monomers, which then nucleate to form fibril nuclei, or oligomers transition to the structure of fibril nuclei without dissociation. We will not only delineate the mechanism of Aβ aggregation, but also shed light on how to modulate this process as a way of therapeutic intervention.

项目总结/摘要 Aβ蛋白的聚集在阿尔茨海默病的发病机制中发挥着核心作用。Aβ聚集 导致形成可溶性低聚物和不溶性原纤维。而淀粉样纤维是主要成分 在阿尔茨海默病脑实质斑块中，Aβ寡聚体被广泛认为是更多的 毒性更强，病理学上更相关有强有力的证据表明，至少某些类型的Aβ 低聚物可经历构象转化以形成原纤维。人们还不太清楚， 低聚物可以重新排列它们的结构以形成原纤维。在这个项目中，我们将结合使用 电子和核磁共振监测Aβ42寡聚体到原纤维的结构变化 转换. Aβ42寡聚体将在存在低浓度去污剂的情况下制备。这些 Aβ42寡聚体是一类稳定的寡聚体，只有在脂质存在下才能转化为原纤维 囊泡低聚物至原纤维的转化之后将进行EPR和NMR实验， 不同的时间点。这项研究将提供见解，是否低聚物解离成单体， 然后成核形成原纤核，或者低聚物转变成原纤核结构而不解离。我们 不仅揭示了Aβ聚集的机制，而且阐明了如何调节这一过程 作为一种治疗干预的方式。