Structure and Mechanism of a Prion-remodeling Factor

朊病毒重塑因子的结构和机制

• 批准号: 8670000
• 负责人: Francis T.F. Tsai
• 金额: $ 31.69万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-07-01 至 2017-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8670000
• 关键词: Address; Adopted; Alzheimer' s Disease; Amyloid; Amyloidosis; Animal Model; Binding; Biochemical; Biological; Biology; Biotechnology; Bovine Spongiform Encephalopathy; Cells; Chemicals; Complex; Disease; Engineering; Family; Genetic; Grant; Health; Homeostasis; Homologous Gene; Human; Huntington Disease; Hybrids; In Vitro; Infection; Infectious Agent; Longevity; Maintenance; Mammals; Mediating; Membrane; Methods; Molecular; Molecular Chaperones; Molecular Conformation; Molecular Machines; Monitor; Mutagenesis; Neurodegenerative Disorders; Nonsense Codon; Pathology; Peptide Hydrolases; Peptides; Prion Diseases; Prions; Protein Family; Protein Structure Initiative; Proteins; Proteome; Proteomics; Reading; Recovery of Function; Research; Rewards; Risk; Role; Sorting - Cell Movement; Stress; Structure; Structure-Activity Relationship; Substrate Interaction; System; Tail; Techniques; Translations; Work; Yeasts; base; biological adaptation to stress; biophysical properties; conformer; in vivo; insight; nanomachine; nanomedicine; non-prion; novel; polypeptide; prevent; protein aggregate; protein aggregation; protein folding; protein misfolding; public health relevance; structural biology; termination factor; three dimensional structure; yeast genetics; yeast prion

DESCRIPTION (provided by applicant): Prions are unconventional, highly infectious agents, which are composed entirely of a protein that adopts an abnormal conformation. In mammals, prion-mediated infections are responsible for several devastating and invariably fatal neurodegenerative diseases, collectively known as transmissible spongiform encephalopathies. A hallmark of prion diseases is the presence of amyloids, which are also associated with the pathology of non-prion diseases, ranging from Alzheimer's and Huntington's disease to systemic amyloidosis. The broad and long-term research objective is to uncover the functional role of molecular chaperones in prion replication. Yeast provides an excellent paradigm to investigate the mechanism of prion replication. [PSI+] is a yeast prion that increases translational read-through of nonsense codons. Like mammalian prions, [PSI+] consist entirely of protein and is formed by self-replicating amyloid conformers of the evolutionary conserved translation termination factor Sup35p (eRF3). The inheritance and maintenance of [PSI+] are governed by Hsp104, a 600-kDa, ring-forming ATP-dependent, protein-remodeling machine, which cooperates with the Hsp70 chaperone system in prion replication and protein disaggregation. The objective of this research is to provide a detailed mechanistic understanding of the prion-remodeling and protein disaggregating activities of Hsp104 and its bacterial homolog ClpB. Three specific aims are proposed: 1) to determine the 3D structure of an Hsp104-substrate complex, 2) to investigate the synergistic interaction between Hsp104 and Hsp70/Hsp40, and 3) to elucidate the mechanism of protein disaggregation and prion replication by the Hsp104 bi-chaperone system. To address our research questions, we will use a multi-facet approach consisting of hybrid structural biology methods, proteomic and chemical biology techniques, and yeast genetics. The combination of these methods provides a powerful approach to yield new mechanistic insight into the structure-function relationship of this remarkable family of ATP-dependent molecular machines in order that this information might be exploited to engineer new nano-machines with novel biological activities with potential applications in biotechnology and nano-medicine.

描述(申请人提供)：普恩病毒是一种非常规的、高度传染性的病原体，完全由一种采用异常构象的蛋白质组成。在哺乳动物中，Prion介导的感染导致了几种毁灭性的、总是致命的神经退行性疾病，统称为传染性海绵状脑病。从阿尔茨海默病、亨廷顿病到全身性淀粉样变性，非普恩疾病的病理都与淀粉样蛋白的存在有关，这是普恩疾病的一个特征。广泛和长期的研究目标是揭示分子伴侣在Pron复制中的功能作用。酵母菌为研究PrP复制机制提供了一个很好的范例。[PSI+]是一种酵母蛋白，可以增加无意义密码子的翻译通读。与哺乳动物一样，[PSI+]完全由蛋白质组成，由进化保守的翻译终止因子Sup35p(ERF3)的淀粉样构象自我复制形成。[PSI+]的遗传和维持由Hsp104控制，Hsp104是一种600 kDa的环形成ATP依赖的蛋白质重塑机器，它与Hsp70伴侣系统合作复制蛋白质和解聚蛋白质。本研究的目的是从机制上对Hsp104及其细菌同源蛋白ClpB的重组和蛋白质解聚活性提供一个详细的了解。1)确定Hsp104-底物复合体的三维结构；2)研究Hsp104与Hsp70/Hsp40之间的协同作用；3)阐明Hsp104双伴侣系统在蛋白质解聚和蛋白复制中的作用机制。为了解决我们的研究问题，我们将使用多方面的方法，包括杂交结构生物学方法，蛋白质组和化学生物学技术，以及酵母遗传学。这些方法的结合提供了一种强有力的方法，可以从新的机制上洞察这一重要的依赖于ATP的分子机器的结构-功能关系，以便利用这些信息来设计具有新的生物学活性的新的纳米机器，在生物技术和纳米医学中具有潜在的应用。