Replication mechanism of human prions

人类朊病毒的复制机制

• 批准号: 8312479
• 负责人: WITOLD K SUREWICZ
• 金额: $ 54万
• 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/8312479
• 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）：感染性病原体中前所未有的prions蛋是由错误折叠的蛋白质组成。哺乳动物的王室倾向于在神经系统中高水平积聚，从而导致致命的神经退行性。人类prion疾病的最常见形式是零星的克鲁特兹菲尔特 - jakob病（SCJD）。 SCJD Prions的起源，频谱和结构尚不清楚。该疾病的特殊表型变异表明，编码不同的CJD prion菌株的致病性prion蛋白（PRPSC）的许多不同构象的存在。此外，在大约40％的SCJD大脑中，不同蛋白水解片段的共存引发了一种有趣的可能性，即在同一宿主中共构构中构型不同的SCJD Prions共存。反过来，这提出了有关SCJD王室起源，其进化和假设干扰的基本问题。该应用的重点是破译SCJD患者中PRPSC的构象，并阐明人类王室复制的基础机制。与蛋白质错误折叠循环扩增（PMCA）和构型依赖性免疫测定（CDI）相连的新型构象方法将用于识别人类PRPSC中的构象和关键域，以编码不同菌株的SCJD prions。 PMCA在体外放大的脑源性PRPSC和类似PRPSC的构象中的氢/氘交换的分析，以及位于定位的自旋标记策略，应使我们能够在自然SCJD Prions复制中阐明应变依赖性构象机制。此外，用串联CDI和PMCA与结构数据相结合的SCJD Prions的复制率的测量应确定脑PRPSC的特定构象特征，以调节复制率，从而调节疾病的进展率。这些研究的最终目的是促进我们对管理人pr菌菌株复制的分子机制的理解，以及PRPSC构象对SCJD表型的影响和疾病的传播性。这种见解对于制定针对SCJD PRPSC或其复制的治疗策略的努力至关重要。