Mechanistic studies of transthyretin misfolding and amyloid formation through a c

通过 c 转甲状腺素蛋白错误折叠和淀粉样蛋白形成的机制研究

• 批准号: 8574332
• 负责人: KWANG HUN LIM
• 金额: $ 35.17万
• 依托单位: EAST CAROLINA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-05-01 至 2017-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8574332
• 关键词: Adopted; Alzheimer' s Disease; Amyloid; Amyloidosis; Collaborations; DNA Sequence Rearrangement; Deposition; Disease; Drug Targeting; Exhibits; Label; Letters; Link; Maps; Methodology; Molecular; Molecular Conformation; Mutate; Mutation; NMR Spectroscopy; Nature; Parkinson Disease; Pathway interactions; Phenotype; Prealbumin; Prion Diseases; Prions; Process; Property; Proteins; Reporting; Research; Resolution; Scheme; Solutions; Structure; System; Testing; Therapeutic; Therapeutic Agents; Time; Tissues; Variant; amyloid formation; amyloid structure; base; conformational conversion; disease phenotype; flexibility; globular protein; human disease; innovation; insight; monomer; mutant; polypeptide; prevent; programs; protein aggregation; protein folding; protein function; protein misfolding; public health relevance; research study; solid state nuclear magnetic resonance; synuclein; therapeutic target; three dimensional structure; tool

DESCRIPTION (provided by applicant): 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,6-9 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 initial transition from the native state to (partly) unfolded intermediate and the end product amyloid are essential to understanding molecular mechanism of amyloid diversity. Effect of the pathogenic mutations on misfolding pathway should also be examined. The comprehensive 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, ?-amyloid and ?-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 both solution and solid-state NMR. Amyloid formation of wild type and more than 100 mutant forms of TTR are known to cause various amyloidoses with enormous phenotype diversity.10 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 studies of conformational transition of the natively folded state to (partly) unfolded amyloidogenic intermediate and structural characterization of amyloid. 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) Misfolding of the native TTR to amyloidogenic monomer. (2) Structural changes of the native ?-structure during amyloid formation. (3) Effect of the mutations on the misfolding pathway and amyloid structure. Mechanistic understanding of the misfolding and amyloid formation pathways would be critical to developing effective therapeutic strategies for TTR amyloidoses.

描述（由申请人提供）：蛋白质错误折叠和淀粉样蛋白的形成与许多疾病（如淀粉样蛋白，prion和阿尔茨海默氏病）有关。 Prion疾病是独一无二的，因为具有独特的分子构象（prion菌株）的本质折叠型蛋白质形成骨料，这是不同的疾病表型。1-3prion菌株可以在蛋白质的一级序列和突变中编码蛋白质的突变，从而诱导不同的菌株，从而导致不同的疾病表型。最近的研究表明，菌株假设适用于也表现出多种疾病表型的其他淀粉样蛋白疾病。1,2,4,5的非固定淀粉样蛋白显示出表现出广泛的构象多样性，6-9可能与表型变体有关。然而，关于淀粉样蛋白的各种错误折叠途径和结构多样性的分子基础知之甚少。从天然状态到（部分）中间体和最终产物淀粉样蛋白的初始过渡对于理解淀粉样蛋白多样性的分子机制至关重要的结构研究。还应检查致病突变对错误折叠途径的影响。然而，由于与不同疾病表型相关的致病突变数量有限，因此对先前研究的淀粉样蛋白蛋白的全面生物物理研究一直在挑战。此外，分别与阿尔茨海默氏症和帕金森氏病相关的最广泛研究的多肽是？ - 淀粉样蛋白和 - 突触核蛋白，分别是本地展开的，这使多肽不可用于初始构象转变的机械性研究（错误构型）。该研究计划旨在使用溶液和固态NMR研究本内折叠蛋白（TTR）的淀粉样蛋白形成机制。已知野生型和100多种突变体形式的淀粉样蛋白形成会引起各种具有巨大表型多样性的淀粉样蛋白。10该提议的主要假设是，TTR的致病性突变形式可能具有独特的错误折叠途径，可能会在不同的毒性活性中产生不同的氧化型构型，这些毒性型在不同的毒性活性中，这可能会导致多样的疾病型和组织类型和组织型在多种毒性中。该假设将通过研究本质折叠状态到（部分）展开的淀粉样蛋白生成中间体和淀粉样蛋白结构表征的构象过渡进行检验。特别是，具有创新标签方案的固态NMR将为淀粉样蛋白多样性提供宝贵的见解。该提案的具体目的是探索：（1）将天然TTR折叠为淀粉样蛋白生成单体。 （2）淀粉样蛋白形成过程中天然结构的结构变化。 （3）突变对错误折叠途径和淀粉样结构的影响。对错误折叠和淀粉样蛋白形成途径的机械理解对于制定有效的TTR淀粉样蛋白治疗策略至关重要。