“Regulation of Protein Quality Control by the VCP AAA-ATPase”

– VCP AAA-ATPase 对蛋白质质量控​​制的调节 –

• 批准号: 10379451
• 负责人: Malavika Raman
• 金额: $ 34.65万
• 依托单位: TUFTS UNIVERSITY BOSTON
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-05-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10379451
• 关键词: ATP phosphohydrolase; Adaptor Signaling Protein; Affect; Aging; Alzheimer' s Disease; Amyotrophic Lateral Sclerosis; Animal Model; Autophagocytosis; Binding; Cell Aging; Cells; Cellular Stress; Cellular Structures; Cessation of life; Clinical; Complex; Degradation Pathway; Development; Disease; Doctor of Philosophy; Funding; Future; Goals; Homeostasis; Huntington Disease; Inclusion Body Myopathy with Early-Onset Paget Disease; Individual; K22 Award; Knock-out; Link; Mediating; Molecular Chaperones; Molecular Target; Mutate; Mutation; Nerve Degeneration; Neurodegenerative Disorders; Neurons; Normal Cell; Organelles; Outcome; Parkinson Disease; Pathway interactions; Play; Prion Diseases; Process; Protein translocation; Proteins; Proteome; Proteomics; Quality Control; Regulation; Role; Site; Stress; Structure; System; Testing; Therapeutic; Toxic effect; Translating; Ubiquitin; base; biological adaptation to stress; cellular targeting; cytotoxic; endoplasmic reticulum stress; glycosylation; high resolution imaging; member; misfolded protein; multicatalytic endopeptidase complex; mutant; neuron loss; new therapeutic target; prevent; protein aggregation; protein complex; protein folding; protein function; proteostasis; recruit; response; small molecule; valosin containing protein mutation; valosin-containing protein

Project Abstract Protein quality control is of critical importance in maintaining cellular protein homeostasis, especially during stress, disease states and aging. These networks are comprised of: 1) chaperones that assist in protein folding and stabilization of intermediates to prevent aggregation, and 2) degradation pathways, such as the ubiquitin proteasome system and autophagy, to eliminate proteins and organelles with sub-optimal function. A decline in protein quality control in aging cells contributes to the development of numerous genetically and clinically distinct neurodegenerative disorders such as amyotrophic lateral sclerosis (ALS), Alzheimer's, Parkinson's, Huntington's and prion diseases. Valosin containing protein (VCP, also known as p97) is a AAA-ATPase that plays an important role in the ubiquitin proteasome system to capture ubiquitylated substrates via designated adaptors to mediate substrate degradation. Mutation of VCP causes several neurodegenerative disorders including ALS and a rare multi-system disorder, inclusion body myopathy, Paget’s disease of the bone and frontotemporal dementia (IBMPFD). The most commonly mutated region of VCP resides at the site of adaptor binding and in certain instances these mutations alter the constellation of adaptors that are bound to VCP skewing its targeting to substrates. A common cellular feature of VCP mutations is the formation and persistence of protein aggregates that fail to be cleared. We have identified a specific VCP-adaptor complex that is targeted to the aggresome, a structure that sequesters misfolded aggregated proteins formed during cell stress. While aggresomes are generally cyto-protective, under conditions where they persist, for example in aging neurons with declining protein quality control pathways, they eventually become cytotoxic. Depletion of the VCP adaptor leads to a deficit in aggresome formation, stabilization of ubiquitylated substrates and triggers ER stress. We hypothesize that VCP mediates aggresome clearance by adaptor specific targeting to enable clearance of specific misfolded or aggregated substrates. We will use a combination of targeted molecular studies, quantitative proteomics and high-resolution imaging to achieve the main objectives of this proposal. We will (1) characterize the VCP aggresome targeted complex to determine mechanisms of targeting and its functions within the aggresome (2) identify ubiquitylated cellular targets of the VCP complex targeted to the aggresome using ubiquitin remnant capture proteomics and (3) determine whether disease-relevant VCP mutations impact its association with the aggresome complex and test if the VCP adaptor can recognize and enable clearance of disease relevant protein aggregates. Successful implementation of this proposal will identify new targets that can be pursued for the development of agents that enable aggregate clearance in a number of neurodegenerative disorders.

项目摘要 蛋白质质量控制在维持细胞蛋白质稳态中至关重要，特别是在 压力、疾病状态和衰老。这些网络包括：1）协助蛋白质折叠的分子伴侣 和稳定中间体以防止聚集，和2）降解途径，如泛素 蛋白酶体系统和自噬，以消除具有次优功能的蛋白质和细胞器。下降 衰老细胞中的蛋白质质量控制有助于许多遗传和临床上不同的 神经变性疾病，如肌萎缩侧索硬化症（ALS）、阿尔茨海默氏病、帕金森氏病、亨廷顿舞蹈病 和朊病毒疾病。含有Valosin的蛋白质（VCP，也称为p97）是一种AAA-ATPase，其在细胞内起作用。 在泛素蛋白酶体系统中的重要作用，通过指定的接头捕获泛素化底物， 介导底物降解。VCP的突变导致几种神经退行性疾病，包括ALS和 一种罕见的多系统疾病，包涵体肌病，佩吉特骨病和额颞叶痴呆症 （IBMPFD）。VCP最常见的突变区域位于接头结合位点，并且在某些情况下， 在一些情况下，这些突变改变了与VCP结合的衔接子的星座，使其靶向偏离VCP。 印刷受体. VCP突变的一个共同的细胞特征是蛋白质聚集体的形成和持续存在 无法清除的。我们已经确定了一个特定的VCP-适配器复合物，该复合物靶向攻击基因组， 一种隔离在细胞应激过程中形成的错误折叠的聚集蛋白的结构。虽然侵略者是 在它们持续存在的条件下，通常具有细胞保护作用，例如在衰老的神经元中， 蛋白质质量控制途径，它们最终成为细胞毒性。VCP适配器的耗尽导致 攻击体形成的缺陷，泛素化底物的稳定和触发ER应激。我们假设 VCP通过衔接子特异性靶向介导攻击基因组清除， 或聚集的基质。我们将结合靶向分子研究、定量蛋白质组学和 高分辨率成像，以实现本提案的主要目标。我们将（1）描述VCP的特征 攻击基因组靶向复合物，以确定靶向机制及其在攻击基因组内的功能（2） 使用泛素残基鉴定VCP复合物的靶向攻击基因组的泛素化细胞靶标 捕获蛋白质组学和（3）确定疾病相关的VCP突变是否影响其与 攻击体复合物，并测试VCP衔接子是否可以识别并能够清除疾病相关蛋白 集料.成功地执行这一建议将确定可在2010 - 2011年期间实现的新目标。 开发能够在许多神经退行性疾病中清除聚集体的药物。