Integrative NMR and biophysical studies of fibrillar protein assemblies in health and disease

健康和疾病中纤维蛋白组装的综合核磁共振和生物物理学研究

• 批准号: 10613473
• 负责人: JEAN S BAUM
• 金额: $ 57.3万
• 依托单位: RUTGERS, THE STATE UNIV OF N.J.
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-05-01 至 2025-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10613473
• 关键词: Address; Amyloid; Architecture; Atomic Force Microscopy; Binding; Binding Sites; Biological; Biology; Biophysics; Cell physiology; Cells; Cellular Assay; Collagen; Collagen Fibril; Complex; Computing Methodologies; Connective Tissue Diseases; Cryoelectron Microscopy; Defect; Disease; Disease Progression; Extracellular Matrix Proteins; Health; Homeostasis; Hour; Inherited; Integrins; Intervention; Link; Molecular; Molecular Conformation; Motion; Mutation; NMR Spectroscopy; Nature; Neurodegenerative Disorders; Osteogenesis Imperfecta; Parkinson Disease; Pathologic; Platelet aggregation; Play; Property; Proteins; Protocols documentation; Role; Specificity; Structure; Surface; Surface Properties; System; Techniques; Therapeutic; Time; Visualization; alpha synuclein; biological systems; biophysical analysis; biophysical tools; design; monomer; nanoscale; novel; novel therapeutic intervention; self assembly; solid state nuclear magnetic resonance; synucleinopathy

Abstract Protein self-assembly into structured fibrils plays both functional and dysfunctional roles in biology. We are investigating two classes of fibril forming proteins: collagen, a fibril that forms essential interactions with numerous proteins and extracellular matrix components for proper cellular function and α-synuclein (αS), an intrinsically disordered protein that self-assembles into oligomers and fibrils that are associated with debilitating synucleinopathies, such as Parkinson’s Disease. While in both cases, fibrils are often thought of as rigid, rather inert, entities, we have recently discovered conformational dynamics that profoundly impact their atomic- to-nano scale properties. Despite the importance of these fibrillar proteins, the molecular determinants of fibril- protein interactions and their impact in health and disease remain unanswered. Thus, the overarching objective of this proposal is to understand how molecular motions and surface properties modulate protein interactions at different assembly stages (monomer, oligomer, fibril), spatial extent (atomic to nanoscale), and temporal regime (picosecond to hours) to promote normal homeostasis or pathological disease states. The unifying theme of this proposal is that we are developing the key techniques and protocols necessary for fibril characterization that recognize the conformational plasticity and diverse interactions of these systems. We use a multifaceted approach integrating solution and solid-state nuclear magnetic resonance spectroscopy, atomic force microscopy, cryo-electron microscopy, computational methods, and link these to cellular experimentation. We are addressing the question of how collagen fibrils recognize their binding partners (we focus in particular on integrin, a key protein involved in platelet aggregation) despite the fact that many binding sites are hidden in the complex collagen fibril architecture. Beyond structure/function in healthy fibrils, we will investigate the impact of GlyX mutations in hereditary connective tissue disease such as Osteogenesis Imperfecta (brittle bone disease) and visualize for the first time how these defects impact on fibril assembly, structure and function. Although a very different biological system, we raise similar fibril interaction questions for αS: cell-to- cell propagation and templated seeding of endogenous αS monomers by fibrils increases the number of fibrils and is one of the primary factors in disease progression. This interaction mechanism is not understood and we will investigate this by first characterizing amyloid surfaces from the atomic to the nano-scale and then visualizing the interactions of the monomers with them. Results will shed light on the nature and specificity of collagen and αS interactions, the biophysical and biological impact of disease-affiliated collagen mutations, and mechanisms of pathological cell-to-cell propagation and seeding of αS aggregates. Elucidating novel interaction mechanisms will aid in design of new therapeutic strategies to rescue compromised collagen interactions or pathological αS aggregation in devastating neurodegenerative disease.

摘要 蛋白质自组装成结构纤维在生物学中既有功能作用，也有功能失调的作用。我们是 研究两类纤维形成蛋白：胶原蛋白，一种与 正常细胞功能和α-突触核蛋白所需的大量蛋白质和细胞外基质成分(αS) 固有的无序蛋白质，自组装成与衰弱有关的寡聚体和纤维 并核病，如帕金森氏病。而在这两种情况下，纤维通常被认为是坚硬的， 相当惰性的实体，我们最近发现构象动力学深刻地影响它们的原子- 到纳米级的特性。尽管这些原纤维蛋白很重要，但原纤维的分子决定因素- 蛋白质的相互作用及其对健康和疾病的影响仍然没有答案。因此，首要目标是 了解分子运动和表面性质是如何调节蛋白质相互作用的 在不同的组装阶段(单体、齐聚物、原纤维)、空间范围(原子到纳米尺度)和时间 制度(皮秒到小时)，以促进正常的体内平衡或病理疾病状态。一元化 这项提议的主题是，我们正在开发纤维所需的关键技术和协议 认识到这些体系的构象可塑性和不同相互作用的特征。我们用 集成溶液和固体核磁共振波谱的多方面方法，原子 力显微镜、低温电子显微镜、计算方法，并将这些与细胞实验联系起来。 我们正在解决胶原纤维如何识别它们的结合伙伴的问题(我们特别关注 关于整合素，参与血小板聚集的关键蛋白)，尽管许多结合位点隐藏在 复杂的胶原纤维结构。除了健康纤维的结构/功能外，我们将研究 GlyX突变对成骨不全(脆性)等遗传性结缔组织病的影响 骨骼疾病)，并首次可视化这些缺陷如何影响纤维组装、结构和 功能。尽管生物系统截然不同，但我们对αS提出了类似的纤维相互作用问题：细胞到细胞- 内源性αS单体的细胞增殖和纤维模板接种增加纤维数量 是疾病进展的主要因素之一。这种相互作用的机制还不清楚，我们 我将通过首先从原子到纳米尺度表征淀粉样蛋白表面，然后 可视化单体与它们的相互作用。结果将有助于阐明 胶原蛋白与αS的相互作用，疾病相关胶原突变的生物物理和生物学影响， 以及αS聚集体病理性细胞间繁殖和播种的机制。释义小说 相互作用机制将有助于设计新的治疗策略来挽救受损的胶原蛋白 破坏性神经退行性疾病中的相互作用或病理性αS聚集。