REPURPOSING PRION PROTEINS AS TRANSLATIONAL AMYLOID-TARGETING THERAPEUTICS FOR ALZHEIMER'S DISEASE

重新利用朊病毒蛋白作为阿尔茨海默病的翻译淀粉样蛋白靶向疗法

• 批准号: 9891697
• 负责人: Zachary Alan Levine
• 金额: $ 12.65万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-06-15 至 2025-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/9891697
• 关键词: Affect; Affinity; Alanine; Alzheimer' s Disease; Alzheimer' s disease related dementia; Alzheimer' s disease therapeutic; Amino Acids; Amyloid; Amyloid Fibrils; Amyloid beta-Protein; Animal Model; Binding; Binding Proteins; Binding Sites; Biological Assay; Biological Models; Biomimetics; Biophysics; Blood - brain barrier anatomy; Brain; Cells; Chemicals; Chromatography; Complex; Dementia; Dot Immunoblotting; Educational workshop; Enzyme-Linked Immunosorbent Assay; Follow-Up Studies; Goals; Heterogeneity; Human; Immersion; Immunoassay; Impaired cognition; Impairment; In Vitro; Joints; Laboratories; Length; Ligand Binding; Link; Lipids; Liquid substance; Measures; Mediating; Membrane Proteins; Mentors; Methodology; Methods; Modeling; Molecular; Molecular Conformation; Molecular Sieve Chromatography; NMR Spectroscopy; Nerve Degeneration; Neurodegenerative Disorders; Neurons; Noise; Optics; Pathologic; Pathway interactions; Peptide aptamers; Peptides; Physiological; PrP; Prion Diseases; Property; Protein Binding Domain; Proteins; Protocols documentation; Rattus; Research; Resources; Sampling; Scanning; Senile Plaques; Severities; Severity of illness; Side; Signal Transduction; Spectrum Analysis; Speed; Structural Models; Structure; Synapses; System; Tertiary Protein Structure; Testing; Thermodynamics; Tissues; Toxic effect; Translations; Water; abeta oligomer; abeta toxicity; age related; amyloid formation; aptamer; base; biophysical analysis; clinically relevant; cost effective; cytotoxicity; design; effectiveness evaluation; experimental study; genome wide screen; in vivo; meetings; molecular dynamics; monomer; next generation; protein complex; relating to nervous system; screening; simulation; synaptic function; targeted treatment; tau Proteins; tau aggregation; therapeutic target

PROJECT SUMMARY Cognitive decline in Alzheimer’s Disease (AD) and many other age-related dementias have long been associated with the presence of insoluble amyloid plaques that disrupt normal synaptic functioning. However, more recent studies have revealed that synapse impairment from AD is much more potently associated with soluble amyloid-beta oligomers (abo), rather than from insoluble fibrils. Soluble oligomers are structurally irregular and promiscuously bind to membrane proteins, thereby dysregulating downstream amyloid assemblies such as tau. These properties, unfortunately, have also made it difficult to experimentally characterize abo, since oligomeric states can be transient or otherwise observed as noise. Multiple genome-wide screening methods have identified cellular prion protein (PrPc) as a putative target of abo, and subsequent studies have confirmed a pathophysiological pathway in AD involving abo-PrPc binding. Interestingly, ab monomers and insoluble fibrils do not bind to PrPc, thus the binding domain of PrPc can be exploited in peptide aptamers to target and stabilize abo. Here, we seek to utilize these interactions by designing biomimetic PrPc peptides that complex soluble abo. Molecular simulations and amyloid-characterizing experiments will be combined to optimize aptamer-abo interactions in order to abrogate binding of abo to PrPc. While aptamers are unlikely to serve as an AD therapeutic, amyloid-targeting PrPc peptides can guide the construction of next-generation agents that cross the blood-brain barrier and potently inhibit the toxicity of abo. Similarly, identification of abo by aptamers can potentially enable the tracking of soluble oligomers through fluorescent tagging during the formation of insoluble fibrils. Given that there are few, if any methodologies to target abo, this proposal would seek to isolate soluble oligomers and identify the limitations of their interactions with membrane proteins. In order to synergistically combine molecular dynamics simulations with experiments, mentoring will be carried out on the use of NMR spectroscopy, chromatography, and ligand-binding assays to measure oligomer structure, size, and the ability to bind PrP proteins, respectively. Mentoring will include regular meetings, coursework, workshops, and immersion in the laboratory of the primary mentor. Additionally, this study will seek to bridge basic biophysical research with clinically-relevant systems through the translation of model aptamers from simulations into experiments. Results will be connected to and interpreted in the context of Alzheimer’s Disease. The protocols and products developed as a result of this study will subsequently inform follow-up studies of soluble amyloid toxicity in live cells, with extensions to multiple neurodegenerative diseases.

项目摘要 阿尔茨海默病（AD）和许多其他与年龄相关的痴呆症的认知能力下降长期以来一直是 与不溶性淀粉样蛋白斑块的存在有关，淀粉样蛋白斑块破坏正常的突触功能。然而，在这方面， 最近的研究表明，AD引起的突触损伤与 可溶性淀粉样蛋白-β低聚物（ABO），而不是来自不溶性原纤维。可溶性低聚物在结构上 不规则和混杂地与膜蛋白结合，从而使下游淀粉样蛋白组装失调 例如tau。不幸的是，这些特性也使得难以通过实验来表征abo，因为 低聚状态可以是短暂的，或者以其他方式作为噪音被观察到。 多种全基因组筛选方法已将细胞朊蛋白（PrPc）确定为假定的靶点 的abo，随后的研究已经证实了AD中涉及abo-PrPc结合的病理生理学途径。 有趣的是，ab单体和不溶性原纤维不与PrPc结合，因此PrPc的结合结构域可以是 在肽适体中用于靶向和稳定ABO。在这里，我们试图通过设计来利用这些相互作用， 与可溶性abo.分子模拟和淀粉样蛋白表征 将结合实验以优化适体-abo相互作用，从而消除abo与PrPc的结合。 虽然适体不太可能用作AD治疗剂，但淀粉样蛋白靶向PrPc肽可以引导AD治疗。 构建下一代药物，可穿过血脑屏障并有效抑制ABO的毒性。 类似地，通过适体识别abo可以潜在地使可溶性寡聚体的跟踪成为可能， 在不溶性原纤维形成期间荧光标记。考虑到很少有（如果有的话） 以ABO为目标，该建议将寻求分离可溶性低聚物，并确定它们相互作用的限制 膜蛋白。 为了协同联合收割机分子动力学模拟与实验，指导将 使用NMR光谱法、色谱法和配体结合测定来测量低聚物 结构、大小和结合PrP蛋白的能力。指导将包括定期会议， 课程作业，研讨会，并沉浸在实验室的主要导师。此外，本研究将寻求 通过模型适体的翻译，将基础生物物理研究与临床相关系统联系起来 从模拟到实验。结果将与阿尔茨海默氏症的背景相关联并进行解释 疾病作为本研究结果开发的方案和产品将随后告知后续行动 活细胞中可溶性淀粉样蛋白毒性的研究，扩展到多种神经退行性疾病。