Solid State NMR Studies of Amyloid Proteins

项目摘要/摘要 提出的研究重点是魔角旋转核磁共振技术的应用和发展。 作为研究淀粉样多肽和蛋白质结构的工具。这项研究涵盖了四个主要方面 主题。 A.淀粉样多肽和蛋白质的结构 (1)Aβ1-42和Aβ1-40：使用1H检测和DNP魔角旋转(MAS)和低温EM 在Aβ上的下列实验：(A)确定Aβ1-40的结构；(B) 病理上重要的斑块播种Aβ1-42；(C)N末端尾巴的结构和结合 尾部抗体Aducanumab；(D)Aβ1-42突变体的结构。 (2)β-2-微球蛋白(β2M)和DeltaN6-β2M：我们计划确定透析相关淀粉样变性蛋白的93个氨基酸β2M-DeltaN6变体的结构。此外，DeltaN6被认为是 体内种植β2M斑块的催化剂。因此，我们还打算研究β2M和DeltaN6的混合物。 (3)淀粉样多态：我们打算确定这三种多态的结构。 来自Sup35的致淀粉样多肽GNNQQNY。它们以一致的1：1：1的人口数量存在 并将提供对定义的结构变化改变13C和15N的方式的第一次研究 轮班。将使用~1H、~(13)C和~(17)O核磁共振表征水分子周围的结构。 GNNQQNY晶格。 B.核磁共振方法如果没有核磁共振方法，上述结构研究都是不可能的 光谱，测量距离和扭转角，以增强信号强度等。因此，我们计划 继续发展对这些结构调查至关重要的方法。(A)我们计划 通过初步准备U-17O/13C/15N GNNQNY来继续这些实验，以进一步开发 然后将其应用于Aβ1-42和Aβ1-40的光谱。这些实验将使用1H 为了优化检测和DNP的灵敏度。Par和Pain一直是MAS的关键 核磁共振结构测定，但它们是测定13C-13C和13C-15N的半定量方法 距离。利用SPINEVOLUTION软件和在模型系统上的实验，我们计划开发 这些方法转化为定量测距技术。

Project Summary/Abstract The proposed research focuses on the application and development of magic angle spinning (MAS) NMR as a tool for structural investigations of amyloid peptides and proteins. The research covers four major topics. A. Structure of Amyloid Peptides and Proteins (1) Aβ1-42 and Aβ1-40: Using 1H detected and DNP magic angle spinning (MAS) and cryoEM we plan the following experiments on Aβ: (a) a determination of the structure of Aβ1-40; (b) the structure of the pathologically important plaque seeded Aβ1-42; (c) the structure of the N-terminal tail and the binding of antibody Aducanumab to the tail; (d) and the structure of mutants for Aβ1-42. (2) Beta-2-microglobulin (β2m) and DeltaN6-β2m: We plan to determine the structure of the 93 AA β2m-DeltaN6 variant of the dialysis related amyloidosis (DRA) protein. In addition, DeltaN6 is thought to be the catalyst that seeds β2m plaques in-vivo. We therefore also intend to study mixtures of β2m and DeltaN6. (3) Amyloid polymorphism: We intend to determine the structure of the three polymorphs of the amyloidiogenic peptide GNNQQNY from Sup35. These are present in a consistent 1:1:1 population and will provide the first study of the manner in which defined structural changes alter 13C and 15N shifts. 1H, 13C and 17O NMR will be used to characterize the structure around the H2O molecules in the GNNQQNY lattice. B. NMR methods None of the above structural studies would be possible absent NMR methods to assign spectra, measure distances and torsion angles, to enhance signal intensities, etc. We therefore plan to continue the development of the methods essential for these structural investigations. (a) We plan to continue these experiments by initially preparing U-17O/13C/15N GNNQQNY to further develop the spectroscopy and then to apply it to spectroscopy of Aβ1-42 and Aβ1-40. The experiments will employ 1H detection and DNP in order to optimize the sensitivity. PAR and PAIN have been essential to MAS NMR structure determinations but they are semiquantitative methods to measure 13C-13C and 13C-15N distances. Using SPINEVOLUTION software and experiments on model systems, we plan to develop these approaches into quantitative distance measurement techniques.