Molecular Mechanisms of Prion and Amyloid Propagation

朊病毒和淀粉样蛋白传播的分子机制

基本信息

批准号：
8470659
负责人：
Christopher P Jaroniec
金额：
$ 27.96万
依托单位：
OHIO STATE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-06-01 至 2016-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8470659
关键词：
Amino Acids Amyloid Amyloid Fibrils Architecture Atomic Force Microscopy Biochemical Biology Bovine Spongiform Encephalopathy C-terminal Cattle Characteristics Chronic Wasting Disease Creutzfeldt-Jakob Syndrome Data Deer Deuterium Disease Exhibits Fingerprint Generations Hamsters Hereditary Cerebral Amyloid Angiopathy Human Hydrogen In Vitro Individual Infectious Agent Link Magic Mammals Measures Mesocricetus auratus Methods Molecular Molecular Conformation Mus Mutation N-terminal NMR Spectroscopy Nature Neurodegenerative Disorders Neurologic PrP PrP variant PrPSc Proteins Prion Diseases Prions Protein Conformation Proteins Public Health Publishing Relaxation Research Resolution Role Scheme Scrapie Seeds Sheep Side Site Solutions Specificity Structural Models Structure Techniques Transmission Electron Microscopy Validation Variant Vertebral column Wild Type Mouse Work Yeasts base conformational conversion conformer design disease phenotype flexibility fungus in vitro Model insight meetings methionylmethionine monomer mutant novel prevent prion hypothesis prion-based protein aggregate restraint scaffold solid state nuclear magnetic resonance transmission process

项目摘要

DESCRIPTION (provided by applicant): The prion concept, according to which proteins alone can be infectious, represents a new paradigm in biology. Such protein-only infectious agents are believed to be responsible for transmissible spongiform encephalopathies, a group of fatal neurodegenerative disorders that include Creutzfeldt-Jakob disease in humans and bovine spongiform encephalopathy in cattle. Mammalian prions propagate by a mechanism involving the conformational conversion of a largely a-helical cellular prion protein, PrPC, to misfolded, ¿-rich amyloid-like aggregates, PrPSc. More recently, the prion hypothesis has been extended further to include the phenomenon of protein conformation-based inheritance in yeast and other fungi. Particularly puzzling features of such conformational infectivity and inheritance are the existence of so-called prion strains linked to discrete disease phenotypes within the same host species, and their role in transmissibility barriers which frequently prevent efficient prion transmission between different species. While recent studies indicate that prion strains originate from the ability of proteins to misfold into multiple distinct conformers in forming self-propagating amyloid aggregates, molecular-level understanding of these phenomena has been hampered by the paucity of high-resolution structural data. In this project we aim to advance the understanding of fundamental aspects of protein conformation-based inheritance and infectivity by providing detailed insights into the molecular mechanisms and structural basis of amyloid propagation and transmissibility barriers for a non-infectious Y145Stop PrP variant (PrP23-144). This C-truncated PrP mutant is associated with hereditary cerebral amyloid angiopathy in humans and exhibits in vitro some of the most fundamental aspects of PrP propagation including the phenomena of prion strains and species barriers. The specific aims focus on the determination and validation of a detailed structural model for human PrP23-144 amyloid aggregates, and elucidation of the structural differences related to the emergence of distinct PrP23-144 amyloid strains with unique transmission characteristics (i.e., seeding specificities) linked to mutations of two critical amino acid residues near the C-terminus of PrP23-144. Modern multidimensional solid-state NMR spectroscopy will be the primary experimental structural technique employed in the study. In addition, we will use hydrogen/deuterium exchange solution NMR methods, atomic force microscopy and tilted-beam transmission electron microscopy.

描述（由申请人提供）：朊病毒的概念代表了生物学中的一种新范式，这种仅由蛋白质构成的感染因子被认为是导致传染性海绵状脑病的原因，这是一组致命的神经退行性疾病。包括人类克雅氏病和牛海绵状脑病，哺乳动物朊病毒主要通过构象转变的机制传播。 α-螺旋细胞朊病毒蛋白，PrPC，错误折叠，¿最近，朊病毒假说已进一步扩展到包括酵母和其他真菌中基于蛋白质构象的遗传现象，这种构象感染性和遗传的特别令人费解的特征是存在这样的。被称为与同一宿主物种内离散疾病表型相关的朊病毒株，以及它们在传播障碍中的作用，而传播障碍经常阻止不同物种之间的朊病毒传播，而最近的研究表明，朊病毒株起源于有效蛋白质错误折叠的能力。在形成自我繁殖的淀粉样蛋白聚集体时，这些现象被分解成多种不同的构象异构体，但由于缺乏高分辨率结构数据，对这些现象的分子水平理解受到了阻碍。在这个项目中，我们的目标是促进对基于蛋白质构象的遗传的基本方面的理解。通过提供对非传染性 Y145Stop PrP 变体 (PrP23-144) 淀粉样蛋白传播和传播障碍的分子机制和结构基础的详细见解。 C-截短的 PrP 突变体与人类遗传性脑淀粉样血管病相关，并在体外表现出 PrP 传播的一些最基本的方面，包括朊病毒株和物种障碍的现象，具体目标集中于详细结构的确定和验证。人类 PrP23-144 淀粉样蛋白聚集体模型，并阐明与具有独特传播特征的不同 PrP23-144 淀粉样蛋白菌株的出现相关的结构差异（即，与 PrP23-144 C 末端附近两个关键氨基酸残基的突变有关的现代多维固态核磁共振波谱将是该研究中采用的主要实验结构技术。交换溶液核磁共振方法、原子力显微镜和倾斜光束透射电子显微镜。