Solid-state NMR Structural Characterizations of Polymorphic Transthyretin Amyloids

多态性运甲状腺素蛋白淀粉样蛋白的固态 NMR 结构表征

• 批准号: 9311581
• 负责人: KWANG HUN LIM
• 金额: $ 13.14万
• 依托单位: EAST CAROLINA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-08-01 至 2022-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9311581
• 关键词: Adopted; Alzheimer' s Disease; Amyloid; Amyloid beta-Protein; Amyloidosis; Biological; Biological Markers; Collaborations; Degenerative Disorder; Deposition; Disease; Docking; Exhibits; Goals; Human; Hydrophobicity; Label; Letters; Link; Molecular; Molecular Conformation; Mutation; Parkinson Disease; Pathogenicity; Pathway interactions; Phenotype; Prealbumin; Prion Diseases; Prions; Process; Proteins; Research; Resolution; Scheme; Structural Models; Structure; Testing; Therapeutic Agents; Tissues; Treatment Efficacy; Variant; alpha synuclein; amyloid formation; amyloid structure; beta pleated sheet; biophysical analysis; conformational conversion; disease phenotype; flexibility; human disease; improved; innovation; insight; interest; interfacial; intermolecular interaction; monomer; mutant; polypeptide; prevent; programs; protein aggregation; protein folding; protein function; protein misfolding; simulation; solid state nuclear magnetic resonance; three dimensional structure; tissue degeneration; tool

Protein misfolding and amyloid formation is implicated in numerous diseases such as amyloidoses, prion and Alzheimer's diseases. Prion disease is unique in that the natively folded prion protein forms aggregates with distinct molecular conformations (prion strains), which underlie different disease phenotypes.1-3 The prion strain may be encoded in the primary sequence and mutations of the protein induce different strains, causing distinct disease phenotypes. Recent studies have suggested the strain hypothesis is applicable to other amyloid diseases that also manifest diverse disease phenotypes.1,2,4,5 Nonprion amyloids were shown to exhibit a wide conformational diversity,6-10 which may be linked to the phenotype variations. However, little is known about molecular basis of the diverse misfolding pathways and structural diversity of amyloid. Structural studies of the amyloid are essential to understanding molecular mechanism of amyloid diversity. Effect of the pathogenic mutations on misfolding pathway should also be examined. The systematic biophysical studies have, however, been challenging for previously investigated amyloidogenic proteins due to the limited number of pathogenic mutations associated with distinct disease phenotypes. In addition, the most extensively studied polypeptides, β-amyloid and α-synuclein associated with Alzheimer's and Parkinson's diseases respectively, are natively unfolded, rendering the polypeptides not amenable for mechanistic studies of the initial conformational transition (misfolding). This research program is aimed at investigating amyloid formation mechanisms of a natively folded protein, transthyretin (TTR), using solid-state NMR. Transthyretin (TTR) is one of more than 30 human proteins that undergo an aberrant conformational change and misassemble into β-structured amyloid. Amyloid formation of wild type and more than 100 mutant forms of TTR are known to cause various amyloidoses with enormous phenotype diversity.11 The main hypothesis of this proposal is that pathogenic mutant forms of TTR may have distinct misfolding pathways, adopting diverse amyloid conformations with different toxic activities, which may result in diverse disease phenotypes and tissue-selective depositions. The hypothesis will be tested through the structural characterization of amyloid derived from wild-type and various pathogenic mutant forms of TTR. In particular, solid-state NMR with innovative labeling schemes will provide valuable insights into amyloid diversity. Specific aims of the proposal are to explore: (1) Native-like structural features of amyloid core regions. (2) Conformational changes of the loop regions during amyloid formation. (3) Quaternary structure of WT and mutant forms of TTR amyloid. Mechanistic understanding of the misfolding and amyloid formation pathways would be critical to developing effective therapeutic strategies for TTR amyloidoses.

蛋白质错误折叠和淀粉样蛋白形成与许多疾病如淀粉样变性， 朊病毒和老年痴呆症。朊病毒病是一种独特的疾病， 具有不同分子构象的聚集体（朊病毒株），它们是不同疾病的基础 1 -3朊病毒株可编码蛋白质的一级序列和突变。 诱导不同的菌株，导致不同的疾病表型。最近的研究表明， 应变假说适用于其他淀粉样蛋白疾病 非朊病毒淀粉样蛋白显示出广泛的构象多样性，6-10， 可能与表型变异有关。然而，对这种蛋白质的分子基础知之甚少。 不同的错误折叠途径和淀粉样蛋白的结构多样性。淀粉样蛋白的结构研究是 这对于理解淀粉样蛋白多样性的分子机制至关重要。病原体的影响 还应检查错误折叠途径上的突变。系统的生物物理学研究， 然而，由于限制，对于先前研究的淀粉样蛋白， 与不同疾病表型相关的致病突变的数量。此外，最 广泛研究的多肽，β-淀粉样蛋白和α-突触核蛋白与阿尔茨海默氏症有关， 帕金森氏病分别是天然未折叠的，使得多肽不适合用于治疗帕金森氏病。 初始构象转变（错误折叠）的机制研究。该研究计划旨在 在研究淀粉样蛋白形成机制的天然折叠蛋白，甲状腺素运载蛋白（TTR），使用 固态NMR。甲状腺素运载蛋白（TTR）是30多种人类蛋白质之一， 构象改变并错误组装成β-结构淀粉样蛋白。野生型淀粉样蛋白形成， 已知超过100种TTR突变形式引起各种淀粉样变性， 表型多样性。11该提议的主要假设是TTR的致病突变形式 可能有不同的错误折叠途径，采用不同的淀粉样蛋白构象， 活性，这可能导致不同的疾病表型和组织选择性沉积。的 将通过来源于野生型的淀粉样蛋白的结构表征来检验这一假设， TTR的各种致病突变形式。特别是具有创新标记的固态NMR 计划将提供有价值的见解淀粉样蛋白的多样性。该提案的具体目标是 探索：（1）淀粉样蛋白核心区的天然样结构特征。(2)的构象变化 淀粉样蛋白形成过程中的环状区域。(3)WT和TTR突变形式的四级结构 淀粉样蛋白对错误折叠和淀粉样蛋白形成途径的机制理解将是 这对于开发TTR淀粉样变性的有效治疗策略至关重要。