Experiments & Computations to Find Aggregation-Prone Ensembles of Alpha-Synuclein

描述（由申请人提供）：a-synuclein （aSyn）是一种内在紊乱的蛋白，以聚集形式出现在帕金森病患者的大脑中。单体到骨料的转化是复杂的。aSyn的聚集速率对氨基酸序列和环境条件的变化非常敏感。理解异步聚合需要描述单体所采用的整体构象，并将它们与聚合行为联系起来。尽管已经提出了许多假设，将aSyn的聚集行为与其相互转换的构象群联系起来，但对aSyn构象群及其与聚集关系的一致分子描述仍然难以捉摸。本研究将核磁共振和计算方法结合起来，对不同序列和环境条件下aSyn的内在无序构象群和聚集的早期阶段进行表征和可视化。目标是确定瞬时20和/或30结构的元素，这些元素是开始聚集的关键，并确定它们的稳定驱动力。确定aSyn单体聚集倾向的结构基础可能对开发用于毒性聚集级联之前聚集步骤的抑制剂至关重要。一旦发展起来，这种综合方法可以应用于其他重要的生物功能或涉及内在无序蛋白质的疾病。公共卫生相关性：帕金森病是第二常见的晚发性神经退行性疾病。a-synuclein是一种参与帕金森病病因学的极其重要的蛋白质，将通过核磁共振和计算方法在分子水平上进行建模。了解a-突触核蛋白单体构象群的作用可能对开发抑制淀粉样蛋白形成的策略至关重要。

DESCRIPTION (provided by applicant): a-synuclein (aSyn) is an intrinsically disordered protein that appears in aggregated form in the brains of patients with Parkinson's disease. The conversion of monomer to aggregate is complex. Aggregation rates of aSyn are very sensitive to changes in amino acid sequence and environmental conditions. Understanding aSyn aggregation requires characterizing the ensemble of conformations adopted by the monomer and correlating them to aggregation behavior. Though many hypotheses have been proposed to relate aSyn's aggregation behavior to its interconverting conformational ensembles, a consistent molecular description of the aSyn conformational ensembles and their relationship to aggregation remains elusive. This proposal integrates NMR and computational approaches to characterize and explicitly visualize the intrinsically disordered conformational ensembles of aSyn and the early stages of aggregation under different sequence and environmental conditions. The goal is to identify the elements of transient 2o and/or 3o structure that are key for initiation of aggregation and determine their stabilizing driving forces. Identifying the structural basis of aSyn monomer aggregation propensity may be critical for developing inhibitors for the aggregation steps that precede the toxic aggregation cascade. Once developed, this integrated approach can be applied to other important biological functions or diseases involving intrinsically disordered proteins. PUBLIC HEALTH RELEVANCE: Parkinson's disease is the second most prevalent of the late onset neurodegenerative diseases. a-synuclein, an extremely important protein involved in the etiology of Parkinson's disease will be modeled at the molecular level by integrating NMR and computational approaches. Understanding the role of the monomeric conformational ensembles of a-synuclein may be critical for developing inhibition strategies against amyloid formation.