International Research Fellowship Program: Solid-State NMR Studies of Amyloid Fibrils

[402114]弗林德斯国际研究奖学金计划使美国科学家和工程师能够在国外进行三到二十四个月的研究。该计划的奖励为联合研究提供了机会，并利用独特或互补的设施、专业知识和国外的实验条件。该奖项将支持Jeremy C. Flinders博士与德国柏林分子药理学研究所的Hartmut Oschkinat博士进行为期22个月的研究。淀粉样蛋白原纤维是一种错误折叠的蛋白质聚集体，与许多严重疾病有关，包括朊病毒和阿尔茨海默病、2型糖尿病和亨廷顿舞蹈病。这些原纤维形成的确切机制目前尚不清楚，主要是由于缺乏足够的原子水平的结构信息。这种错误折叠形成的结构传统上很难研究，因为它们由长而细的不溶且不结晶的细丝组成。然而，它们适合使用最新的固态核磁共振（NMR）技术进行研究。本研究项目的重点是确定一个模型淀粉样蛋白系统的高分辨率结构，并利用这些信息来研究纤维的形成。由于样品质量直接影响所得数据，因此目前的样品制备方法也在进行优化。现有的核磁共振数据收集技术不足以实现该项目的目标，因此，新的核磁共振和样品制备技术正在开发和改进，以收集结构确定所需的数据。尽管它们之间存在强相互作用的固有问题，但人们正在努力从样品中所有类型的核中提取结构信息。所得到的远近距离约束被输入到结构计算程序中。纤维形成的动力学和热力学也在深入研究中。从两个方面处理这个问题可以更好地理解所收集的有时模棱两可或复杂的数据。利用几种生化和生物物理技术的信息，不断测试和改变纤维形成的工作模型。

0402114FlindersThe International Research Fellowship Program enables U.S. scientists and engineers to conduct three to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad.This award will support a twenty-two-month research fellowship by Dr. Jeremy C. Flinders to work with Dr. Hartmut Oschkinat at Institute for Molecular Pharmacology in Berlin, Germany.Amyloid fibrils are misfolded protein aggregates associated with a number of serious diseases, including prion and Alzheimer's disease, type II diabetes, and Huntington's disease. The exact mechanism of formation for these fibrils is currently not understood, primarily due to a lack of sufficient atomic-level structural information. The structures formed by such misfolding have traditionally been difficult to study, since they comprise long, thin filaments that are insoluble and do not crystallize. They are, however, suitable for study using recent solid-state nuclear magnetic resonance (NMR) techniques. The focus of this research project is determining the high-resolution structure of a model amyloid system and using this information to investigate fibril formation. Since sample quality directly affects the resulting data, current methods of sample preparation are also being optimized. Existing techniques for collecting NMR data are not sufficient for the goals of this project, therefore novel NMR and sample preparation techniques are being developed and refined to gather the needed data for structure determination. Considerable effort is being made to extract structural information from all types of nuclei in samples, despite inherent issues of strong interactions among them. Short and long-range distance constraints obtained are being inputted into structure calculation programs. Also being intensely studied is the kinetics and thermodynamics of fibril formation. Approaching this problem from two fronts allows for a better understanding of the sometimes ambiguous or complicated data collected. A working model of fibril formation is constantly being tested and altered using information from several biochemical and biophysical techniques.