Structural Characterization of Amyloid Fibrils Using Deep UV Raman Spectroscopy

描述（由申请人提供）：淀粉样蛋白原纤维与许多衰弱性疾病有关，如阿尔茨海默病、帕金森病、亨廷顿病、朊病毒病、家族性淀粉样蛋白多发性神经病、老年性全身性淀粉样变性和II型糖尿病等。合理设计成功的治疗策略需要淀粉样蛋白原纤维的详细结构表征。固体核磁共振和x射线微晶体学应用于淀粉样蛋白的短肽片段，对我们了解纤维核心结构有很大贡献。该项目的主要目标是利用深紫外共振拉曼光谱结合氢-氘交换来扩展我们对淀粉样蛋白纤维结构的理解。这种新方法，最近在我们的实验室开创，不需要同位素标记，并创造了一个机会，弥合我们在模型短肽微晶的结构变化和淀粉样蛋白原纤维的核心结构之间的差距。我们将确定和分类由全长蛋白制备的淀粉样蛋白原纤维的核心结构。据推测，朊病毒蛋白聚集体的传染性差异以及克雅氏病患者明显症状的相关差异可能是由于淀粉样蛋白多态性所致。小分子可以潜在地操纵聚集体形态，并为抑制有毒聚集体形成的治疗方法提供基础。因此，至关重要的是：(i)有一个强大的方法来表征多晶型，（ii）了解淀粉样多晶型的性质及其毒性，以及（iii）最终能够控制（抑制）有毒多晶型的形成。我们将测试关于实现功能多态性的结构水平的替代假设。在未来的研究中，当充分发展时，所提出的方法将使体内和体外淀粉样蛋白原纤维的比较结构表征成为可能。这将弥合神经退行性疾病的体内和体外研究之间的差距。特别是，该方法将提供揭示感染性和非感染性淀粉样蛋白结构决定因素的独特信息。

DESCRIPTION (provided by applicant): Amyloid fibrils are associated with numerous debilitating diseases such as Alzheimer's disease, Parkinson's disease, Huntington's diseases, prion disease, familial amyloid polyneuropathy, senile systemic amyloidosis and type II diabetes, etc. The rational design of successful therapeutic strategies calls for detailed structural characterization of amyloid fibrils. Solid-state NMR and X-ray microcrystallography applied to short peptide fragments of amyloidogenic proteins have contributed greatly to our knowledge about the fibril core structure. The main goal of this project is to extend our understanding of the amyloid fibril structure by utilizing deep ultraviolet resonance Raman spectroscopy combined with hydrogen-deuterium exchange. This new method, recently pioneered in our laboratory, does not require isotope labeling and creates the opportunity for bridging the gap between our extended knowledge in the structural variations of model short peptide microcrystals and the core structure of amyloid fibrils prepared from entire proteins. We will determine and classify the core structure of amyloid fibrils prepared from full-length proteins. It has been postulated that differences in infectivity of prion protein aggregates, and related differences in the apparent symptoms of Creutzfeldt-Jakob disease patients, are possible due to amyloid polymorphism. Small molecules could potentially manipulate aggregate morphology and provide the basis for therapeutic approaches to suppress the formation of toxic aggregates. Therefore, it is critical to (i) have a robust method for structural characterization of polymorphs, (ii) understand the nature of amyloid polymorphs and their toxicity, and (iii) eventually, be able to control (suppress) the formation of toxic polymorphs. We will test alternative hypothesis concerning the level of structure at which functional polymorphisms are realized. When fully developed, in future studies, the proposed approach will make possible the comparative structural characterization of in vivo and in vitro amyloid fibrils. This will bridge the gap between in vivo and in vitro studies of neurodegenerative diseases. In particular, the method will provide unique information revealing the structural determinants of infectious and non-infectious amyloids. PUBLIC HEALTH RELEVANCE: Successful outcomes of the proposed study will not only improve our understanding of amyloid fibril structure in general and the nature of amyloid polymorphs and their toxicity in particular, but also provide the basis for the development of therapeutic approaches to suppress the formation of toxic aggregates. When fully developed, the proposed approach will make possible the comparative structural characterization of in vivo and in vitro amyloid fibrils and bridge the gap between in vivo and in vitro studies of neurodegenerative diseases.