A New E3 Ligase Implicated in Protein Quality Control and Neurodegeneration

一种与蛋白质质量控​​制和神经变性有关的新 E3 连接酶

• 批准号: 8590232
• 负责人: CLAUDIO A.P. JOAZEIRO
• 金额: $ 41.04万
• 依托单位: SCRIPPS RESEARCH INSTITUTE, THE
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-01-15 至 2016-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8590232
• 关键词: Afferent Neurons; Alzheimer' s Disease; Amyotrophic Lateral Sclerosis; Animal Model; Basic Science; Binding; Biochemical; Biochemistry; Biological; Biological Assay; Biological Process; Cells; Cellular biology; Defect; Development; Disease; Disease model; Drug Targeting; Eukaryota; Eukaryotic Cell; Exhibits; Gene Expression; Genes; Genetic; Goals; Homologous Gene; Human; Huntington Disease; In Vitro; Lead; Mammalian Cell; Mammals; Mass Spectrum Analysis; Mediating; Messenger RNA; Modeling; Modification; Molecular; Molecular Chaperones; Molecular Genetics; Motor Neurons; Mus; Mutation; Names; Nerve Degeneration; Neurodegenerative Disorders; Organism; Orthologous Gene; Paralysed; Parkinson Disease; Pathogenesis; Pathway interactions; Poly(A) Tail; Prevalence; Process; Production; Proteins; Public Health; Quality Control; Reaction; Regulation; Reporting; Research; Research Design; Research Proposals; Ribosomes; Role; Saccharomycetales; Signal Transduction; Specific qualifier value; System; Terminator Codon; Testing; Therapeutic Intervention; Tissues; To specify; Translations; Ubiquitin; Ubiquitination; Work; Yeasts; base; early onset; gene discovery; gene function; mRNA Decay; mouse model; novel; novel therapeutics; polypeptide; protein aggregate; protein aggregation; protein degradation; reconstitution; tissue culture; ubiquitin-protein ligase; yeast genetics

7. PROJECT SUMMARY Background and relevance: The goal of this basic research proposal is to better understand the causes of neurodegenerative disorders at the molecular level. Among the best known examples are Alzheimer's, Parkinson's and Huntington's diseases, and Amyotrophic Lateral Sclerosis (ALS). Neurodegenerative diseases are incurable and debilitating conditions with increasing prevalence, and without their pathogenic mechanisms being elucidated in sufficient detail, our ability to generate a rationale for corrective therapeutic interventions is greatly limited. We had previously characterized a novel mouse model of neurodegeneration caused by mutation of the LISTER gene. Consistent with an important biological function, this gene is conserved in all organisms from yeast to humans. Accordingly, we have been utilizing various models to discover the gene function and how defects in this function may lead to the disease. The LISTER gene encodes a protein that acts as an E3 ubiquitin ligase, named Listerin. More recently, using yeast we discovered a function for Listerin that is consistent with a role in neurodegeneration in mammals: it functions in a process known as protein quality control whereby aberrant proteins are targeted for degradation. Specifically, its targets are proteins encoded by defective mRNA lacking stop codons ("non-stop proteins"). Listerin functions by tagging those aberrant proteins with molecules of ubiquitin (ubiquitination), which often acts as a destruction signal. Mutation of Listerin causes those toxic proteins to accumulate. With the proposed research we plan to specify the features of Listerin-mediated ubiquitination and expand the findings towards disease. Objective/Hypothesis: Our main hypotheses are that (a) Listerin acts in protein quality control by ubiquitinating non-stop polypeptides stalled in ribosomes, and (b) defective Listerin-mediated degradation leads to the formation of protein aggregates and inclusions, which are hallmarks of neurodegeneration. The Specific Aims are to characterize Listerin's function in non-stop protein degradation, to investigate the extent of conservation of Listerin's function in protein quality control, and to investigate how defects in this function lead to neurodegeneration. Our long-term objective is to help elucidate molecular mechanisms involved in the pathogenesis of human neurodegenerative disease. Study design: We will use biochemistry and yeast molecular genetics to specify how the E3 recognizes its specific target substrates; mammalian tissue culture and biochemistry to investigate the regulation of non-stop protein degradation by mammalian Listerin and biochemistry and cell biology to study the consequences of non-stop protein accumulation in cells.

7. 项目概要 背景和相关性：这项基础研究计划的目标是更好地了解 分子水平的神经退行性疾病。最著名的例子是阿尔茨海默病， 帕金森病、亨廷顿病以及肌萎缩侧索硬化症 (ALS)。神经退行性疾病 是无法治愈且使人衰弱的疾病，且患病率不断增加，且没有致病机制 经过足够详细的阐明，我们为纠正性治疗干预提供理由的能力是 大大受限。我们之前已经描述了一种由以下原因引起的神经变性的新型小鼠模型： LISTER 基因突变。与重要的生物学功能一致，该基因在所有物种中都是保守的 从酵母到人类的生物体。因此，我们一直在利用各种模型来发现该基因 功能以及该功能的缺陷如何导致疾病。 LISTER 基因编码的蛋白质 作为 E3 泛素连接酶，命名为 Listerin。最近，我们利用酵母发现了李斯特林的功能 这与哺乳动物神经退行性变中的作用一致：它在称为蛋白质的过程中发挥作用 质量控制，以异常蛋白质为目标进行降解。具体来说，它的目标是蛋白质 由缺乏终止密码子的缺陷 mRNA（“非终止蛋白”）编码。李施德林通过标记那些来发挥作用 具有泛素分子（泛素化）的异常蛋白质，通常充当破坏信号。突变 李施德林会导致这些有毒蛋白质积聚。通过拟议的研究，我们计划指定 李施德林介导的泛素化的特征并将发现扩展到疾病。 目的/假设：我们的主要假设是 (a) 李施德林通过以下方式发挥蛋白质质量控​​制作用： 泛素化、不间断的多肽在核糖体中停滞，以及 (b) 有缺陷的李施德林介导的降解 导致蛋白质聚集体和内含物的形成，这是神经退行性变的标志。 具体目标是表征李斯特林在不间断蛋白质降解中的功能，以研究 李施德林在蛋白质质量控​​制中功能的保守程度，并研究该缺陷如何影响 功能导致神经退行性变。我们的长期目标是帮助阐明分子机制 参与人类神经退行性疾病的发病机制。 研究设计：我们将使用生物化学和酵母分子遗传学来具体说明 E3 如何识别其 特定目标底物；哺乳动物组织培养和生物化学研究不间断的调控 哺乳动物李斯特菌蛋白降解以及生物化学和细胞生物学研究其后果 细胞内不间断的蛋白质积累。