Replication mechanism of human prions

人类朊病毒的复制机制

• 批准号: 8512826
• 负责人: WITOLD K SUREWICZ
• 金额: $ 50.78万
• 依托单位: CASE WESTERN RESERVE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-08-15 至 2016-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8512826
• 关键词: Antibodies; Biologic Characteristic; Biological Assay; Brain; Classification; Code; Complement; Complex; Coupled; Creutzfeldt-Jakob Syndrome; Data; Deuterium; Development; Disease; Endopeptidase K; Evolution; Foundations; Goals; Human; Hydrogen; Immunoassay; In Vitro; Laboratory Study; Lead; Mass Spectrum Analysis; Measurement; Measures; Mesocricetus auratus; Methods; Molecular; Molecular Conformation; Mus; Nerve Degeneration; Nervous system structure; Neurodegenerative Disorders; Parents; Pathogenesis; Patients; Peptide Hydrolases; PrP sequence; PrPC Proteins; PrPSc Proteins; Prion Diseases; Prions; Procedures; Process; Property; Protein Precursors; Protocols documentation; Reaction; Recombinants; Resistance; Resolution; Rodent; Seeds; Serial Passage; Site; Somatic Mutation; Spectroscopy, Fourier Transform Infrared; Spin Labels; Structural Models; Structure; Structure-Activity Relationship; Therapeutic; Therapeutic Intervention; Western Blotting; age related; base; conformer; design; disease phenotype; human PrP; insight; novel; novel therapeutics; pathogen; prion-based; protein misfolding; protein misfolding cyclic amplification; research study; trait

DESCRIPTION (provided by applicant): Prions, unprecedented among infectious pathogens, are composed of misfolded proteins. Mammalian prions tend to accumulate at high levels in the nervous system, causing fatal neurodegeneration. The most common form of human prion disorders is sporadic Creutzfeldt-Jakob disease (sCJD). The origin, spectrum, and structure of sCJD prions are unknown. The extraordinary phenotypic variability of the disease suggests the existence of many different conformers of pathogenic prion protein (PrPSc) coding for distinct CJD prion strains. Moreover, the co-existence of different proteolytic fragments of PrPSc in approximately 40% of sCJD brains has raised the intriguing possibility that conformationally distinct sCJD prions coexist in the same host. This, in turn, raises fundamental questions about the origin of sCJD prions, their evolution and hypothetical interference. The focus of this application is to decipher the conformation of PrPSc in sCJD patients and to elucidate the mechanism underlying the replication of human prions. Novel conformational methods in tandem with protein misfolding cyclic amplification (PMCA) and conformation-dependent immunoassay (CDI) will be used to identify the conformations and critical domains in human PrPSc that code for different strains of sCJD prions. The analysis of hydrogen/deuterium exchange in brain-derived PrPSc and PrPSc-like conformers amplified in vitro by PMCA, together with site-directed spin labeling strategy, should allow us to elucidate the strain- dependent conformational mechanism in the replication of natural sCJD prions. Furthermore, measurements of replication rates of sCJD prions with tandem CDI and PMCA combined with structural data should determine the specific conformational features of brain PrPSc that modulate replication rates and thus the progression rate of the disease. The ultimate goal of these studies is to advance our understanding of the molecular mechanisms governing the replication of human prion strains and the impact of PrPSc conformation upon the sCJD phenotype and transmissibility of the disease. This insight is critical for efforts to develop therapeutic strategies targeting sCJD PrPSc or its replication.

描述（由申请人提供）：朊病毒是感染性病原体中前所未有的，由错误折叠的蛋白质组成。哺乳动物朊病毒往往会在神经系统中大量积累，导致致命的神经退行性变。人类朊病毒疾病最常见的形式是散发性克雅氏病（sCJD）。sCJD朊病毒的起源、谱和结构尚不清楚。这种疾病的非凡表型变异性表明存在许多不同的致病性朊蛋白（PrPSc）编码不同的CJD朊病毒株的构象。此外，在大约40%的sCJD脑中，PrPSc的不同蛋白水解片段的共存提出了构象不同的sCJD朊病毒共存于同一宿主中的有趣的可能性。这反过来又提出了关于sCJD朊病毒的起源，它们的进化和假设的干扰的基本问题。本申请的重点是破译的构象的朊蛋白在sCJD患者和阐明的机制，人类朊病毒的复制。新的构象方法串联蛋白质错误折叠循环扩增（PMCA）和构象依赖性免疫测定（CDI）将被用来确定的构象和关键结构域的人PrPSc编码不同菌株的sCJD朊病毒。通过PMCA体外扩增脑源性PrPSc和PrPSc样构象异构体的氢/氘交换分析，以及定点自旋标记策略，将使我们能够阐明天然sCJD朊病毒复制中的应变依赖性构象机制。此外，sCJD朊病毒的复制率与串联CDI和PMCA结合结构数据的测量应确定特定的脑PrPSc的构象特征，调节复制率，从而疾病的进展速度。这些研究的最终目标是推进我们对人类朊病毒株复制的分子机制以及PrPSc构象对sCJD表型和疾病传播性的影响的理解。这种认识对于开发针对sCJD PrPSc或其复制的治疗策略的努力至关重要。