Molecular Chaperones and Protein Degradation

分子伴侣和蛋白质降解

基本信息

批准号：
9912181
负责人：
ALFRED L GOLDBERG
金额：
$ 54.58万
依托单位：
HARVARD MEDICAL SCHOOL
依托单位国家：
美国
项目类别：
财政年份：
1995
资助国家：
美国
起止时间：
1995-08-01 至 2021-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9912181
关键词：
26S proteasome Affect Alzheimer&apos s Disease Attention Binding Binding Proteins Biochemical Biological Brain Cell Cycle Progression Cells Clustered Regularly Interspaced Short Palindromic Repeats Complex Cryoelectron Microscopy Cyclic AMP Cyclic AMP-Dependent Protein Kinases Cyclic GMP-Dependent Protein Kinases Enzymes Epinephrine Exercise Fasting Genes Glucagon Goals Heart Heat-Shock Response Hepatocyte Hormones Human Learning Liver Mammalian Cell Mediating Modification Molecular Chaperones Mus Muscle Muscular Atrophy Mutation Neurodegenerative Disorders Neurons Neurotransmitters Normal Cell Pathway interactions Phosphorylation Phosphotransferases Physiological Production Proteasome Binding Protein Kinase Proteins Proteolysis Proteomics Quality Control RAD23B gene Regulation Reporting Strenuous Exercise Stress Structure Testing Therapeutic Tissues Ubiquitin Ubiquitination calmodulin-dependent protein kinase II in vivo interest misfolded protein multicatalytic endopeptidase complex mutant novel parkin gene/protein particle protein activation protein degradation proteostasis proteotoxicity tool ubiquilin

项目摘要

Project Summary / Abstract The great majority of proteins in mammalian cells are degraded by the ubiquitin (Ub) proteasome pathway (UPS). Although it is generally assumed that rates of protein breakdown by the UPS are determined solely through control of ubiquitination, recent studies have shown that the proteolytic capacity of 26S proteasomes is also tightly regulated and influences rates of proteolysis in cells. We recently made the exciting finding that protein kinase A (PKA) by phosphorylating subunit RPN6 enhances the proteasome’s multiple activities and thereby increases the cell’s capacity to degrade misfolded, aggregation-prone proteins, including mutant proteins that cause Alzheimer’s Disease and ALS. Because of its importance in cell regulation and therapeutic potential, we are pursuing in depth studies of the biochemical mechanisms and physiological importance of 26S phosphorylation by PKA and other protein kinases, as well as studies of the newly discovered ability of several proteasome-binding proteins to stimulate its activities. We hope to understand more fully how PKA enhances proteasome function and influences the structure of its 19S regulatory particle. Proteomic studies are planned to identify the short-lived cell proteins degraded faster upon Rpn6 phosphorylation. A valuable tool in these biochemical and structural studies will be construction by CRISPR gene editing of mutant lines carrying phosphomimetic and phosphodead Rpn6 mutations. Selected studies will test if three other kinases reported to phosphorylate proteasome subunits (e.g. protein Kinase G, CamKinase II, and DYRK2), or others alter proteasome function and protein turnover in similar ways as PKA. cAMP/PKA mediate the actions of many hormones and neurotransmitters, and we recently showed that epinephrine and glucagon trigger proteasome activation in hepatocytes by this mechanism. Upon fasting of mice, in muscle and liver Rpn6 becomes phosphorylated and proteasomes activated, as we also found in human muscles after intense exercise. We plan to explore further these actions, which are of clear physiological interest and demonstrate that surprisingly many major hormones can rapidly enhance protein homeostasis by altering proteasome function. Related studies will probe the mechanisms of proteasome activation by certain 26S-binding proteins. 1) The ZFAND protein, ZNF216, which is induced and essential for muscle atrophy, stimulates the proteasome’s degradative activity. 2) The related ZFAND protein, AIRAP, which is induced in heat shock, may cause the marked activation of 26S proteasomes that we recently discovered occurs rapidly on heat shock. 3) We also recently found that the UBL domain, through which many proteins bind to the 26S, by itself can stimulate proteasome activity. We believe this activation is an important new aspect of the functioning of the DUB Usp14 and of the UBL-UBA shuttling factors (e.g. Rad23) that deliver Ub conjugates to the proteasome.

项目概要/摘要哺乳动物细胞中的绝大多数蛋白质被泛素 (Ub) 蛋白酶体降解尽管通常认为 UPS 的蛋白质分解率是确定的。最近的研究表明，仅通过控制泛素化，26S 的蛋白水解能力蛋白酶体也受到严格调控并影响细胞中的蛋白水解速率。发现蛋白激酶 A (PKA) 通过磷酸化 RPN6 亚基增强了蛋白酶体的倍数活性，从而提高细胞降解错误折叠、易于聚集的蛋白质的能力，包括导致阿尔茨海默氏病和肌萎缩侧索硬化症的突变蛋白，因为它在细胞调节和功能方面很重要。潜力，我们正在对生化机制和生理学进行深入的治疗研究 PKA 和其他蛋白激酶 26S 磷酸化的重要性，以及新的研究我们发现了几种蛋白酶体结合蛋白刺激其活性的能力。更全面地了解 PKA 如何增强蛋白酶体功能并影响其 19S 调节颗粒的结构。蛋白质组学研究计划鉴定 Rpn6 降解速度更快的短寿命细胞蛋白 CRISPR 将构建这些生化和结构研究中的一个有价值的工具。选定的研究将对携带拟磷和磷酸死 Rpn6 突变的突变系进行基因编辑。测试其他三种激酶是否报告磷酸化蛋白酶体亚基（例如蛋白激酶 G、CamKinase II、和 DYRK2），或其他以与 PKA 类似的方式改变蛋白酶体功能和蛋白质周转的蛋白。 cAMP/PKA 介导许多激素和神经递质的作用，我们最近表明肾上腺素和胰高血糖素通过这种机制触发肝细胞中的蛋白酶体激活。小鼠的肌肉和肝脏中的 Rpn6 被磷酸化，蛋白酶体被激活，正如我们在我们计划进一步探索这些在剧烈运动后的肌肉动作，这些动作是明确的。生理学兴趣并证明令人惊讶的是许多主要激素可以快速增强蛋白质相关研究将探讨蛋白酶体的机制。某些 26S 结合蛋白的激活 1) ZFAND 蛋白 ZNF216，它是诱导的并且是必需的。肌肉萎缩，刺激蛋白酶体的降解活性 2) 相关的 ZFAND 蛋白，AIRAP，它。在热休克中诱导，可能会导致我们最近发现的 26S 蛋白酶体的显着激活 3) 我们最近还发现了 UBL 结构域，许多蛋白质都通过该结构域发生。与 26S 结合，其本身可以刺激蛋白酶体活性，我们相信这种激活是一个重要的新功能。 DUB Usp14 和提供 Ub 的 UBL-UBA 穿梭因子（例如 Rad23）的功能方面与蛋白酶体缀合。

项目成果

期刊论文数量（79）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Control of proteasomal proteolysis by mTOR.

DOI：
10.1038/nature16472
发表时间：
2016-01-21
期刊：
Nature
影响因子：
64.8
作者：
Zhao J;Garcia GA;Goldberg AL
通讯作者：
Goldberg AL

Raising cGMP restores proteasome function and myelination in mice with a proteotoxic neuropathy.

提高 cGMP 可恢复患有蛋白毒性神经病的小鼠的蛋白酶体功能和髓鞘形成。

DOI：
10.1093/brain/awab249
发表时间：
2022
期刊：
Brain : a journal of neurology
影响因子：
0
作者：
VerPlank,JordanJS;Gawron,Joseph;Silvestri,NicholasJ;Feltri,MLaura;Wrabetz,Lawrence;Goldberg,AlfredL
通讯作者：
Goldberg,AlfredL

Trim32 reduces PI3K-Akt-FoxO signaling in muscle atrophy by promoting plakoglobin-PI3K dissociation.