Single-Molecule Study of Synuclein Folding/Fibrillation

描述（由申请人提供）：α-突触核蛋白与几种神经退行性疾病的发病机制有关，包括两种最常见的神经退行性疾病，阿尔茨海默病和帕金森病。了解突触核蛋白错误折叠和纤维聚集体形成的分子基础是预防和治疗这些疾病的重要步骤。提出的研究的主要目的是回答问题，不同的蛋白质折叠/未折叠的构象如何有助于寡聚化，以及随后形成的纤维状聚集体。此外，溶剂条件的改变对突触核蛋白折叠和聚集机制的影响也将被探讨。一种新的生物物理技术是单分子荧光光谱，特别是最近开发的单对荧光共振能量转移（SP-FRET）扩散方法。单分子方法具有直接探测标准系综方法无法获得的不同结构分布和动态异质性的优点，并且具有检测稀有蛋白质状态的潜力，这些状态可能是使势能景观向蛋白质错误折叠和聚集倾斜的构象陷阱。

DESCRIPTION (provided by applicant): Alpha-synuclein has been implicated in the pathogenesis of several neurodegenerative disorders including the two most common ones, Alzheimer's disease and Parkinson's disease. Understanding the molecular basis of synuclein misfolding and fibril aggregate formation is an essential step in the prevention and cure of these disorders. The major thrust of the proposed study is to answer questions as to how different protein folded/unfolded conformations contribute to oligomerization, and the subsequent formation of fibrillar aggregates. In addition, the effects of alterations in solvent conditions on the mechanism of synuclein folding and aggregation will be explored. A novel biophysical technique to be employed is single-molecule fluorescence spectroscopy, in particular the recently developed single-pair fluorescence resonance energy transfer (sp-FRET) diffusion method. Single-molecule methods have the advantage of directly probing different structural distributions and dynamic heterogeneity not accessible to standard ensemble methods, and the potential to detect rare protein states that could be the conformational traps that tilt the potential energy landscape towards protein misfolding and aggregation.