Investigating the role of HSC70 AMPylation on nuclear localization and chaperone function

研究 HSC70 AMPylation 对核定位和伴侣功能的作用

基本信息

批准号：
10490968
负责人：
Shannon Marie Lacy
金额：
$ 3.87万
依托单位：
UNIVERSITY OF MICHIGAN AT ANN ARBOR
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-07-01 至 2024-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10490968
关键词：
ATP phosphohydrolase Acute Adenosine Monophosphate Age Amyloid fibers Autophagocytosis Autophagosome Binding Biological Assay Caenorhabditis elegans Cardiac Cardiac Myocytes Cardiovascular Diseases Cause of Death Cell Culture Techniques Cell Fractionation Cell Line Cell Nucleus Cell physiology Cells Cellular Stress Cessation of life Coronary heart disease Cytosol Data Defect Defense Mechanisms Dysmyelopoietic Syndromes Failure Family Goals Heart Heart Diseases Heat Stress Disorders Heat shock proteins Heat-Shock Proteins 70 Heat-Shock Response Hypoxia Immunofluorescence Microscopy Impairment In Vitro Influenza Ischemia Knock-out Knockout Mice Knowledge Link Luciferases Mediating Modeling Molecular Molecular Chaperones Movement Mutate Myocardial Ischemia Nuclear Nuclear Import Nuclear Localization Signal Nuclear Protein Nuclear Translocation Orthologous Gene Patients Pharmacologic Substance Physiology Post-Translational Protein Processing Process Protein S Proteins Quality Control Recycling Regulation Risk Role Signal Transduction Site Stress System Testing Therapeutic Threonine Transgenic Organisms Work base cardiovascular risk factor chaperonin heart function misfolded protein novel nucleocytoplasmic transport prevent protein aggregation protein degradation protein folding proteostasis recruit response

项目摘要

Project Summary Coronary heart disease, also called Ischemic Heart Disease (IHD), is the leading cause of death worldwide. Repeated episodes of cardiac stress in IHD patients leads to an increase in misfolded proteins in their hearts. In response to this acute onset of cellular stress, heat shock proteins (HSP)s are upregulated in myocardiocytes and help restore protein homeostasis (proteostasis). Heat shock cognate 71 kDa (HSC70) is an essential, HSP70 chaperone that is located in the cytosol in the absence of cellular stress. This ATP-dependent chaperone actively refolds, degrades, and disaggregates proteins. HSC70 is also critical for autophagy, a cellular recycling/degradation process that protects the heart from misfolded proteins following ischemia. Impaired HSC70 function has been implicated in heart disease, yet despite the critical role of HSC70 in cellular physiology, the molecular mechanisms that regulate nuclear transport and govern the disparate functions of HSC70 remain unknown. Protein AMPylation recently emerged as a distinct PTM that regulates HSP70 family chaperones through the addition of adenosine monophosphate (AMP) to threonine residues. This process is catalyzed by the mammalian AMPylase, HYPE. My preliminary work revealed that HYPE AMPylates HSC70 on two sites, and increased cellular AMPylation levels prevent the nuclear-cytosolic shuttling of HSC70 as well as its ATPase activity. I also found that, similar to decreased levels of the HSC70 ortholog HSP-1, increased AMPylation inhibits autophagosome formation in C. elegans. These data suggest that HYPE-mediated AMPylation of HSC70 inhibits its critical functions associated with maintaining proteostasis, including nuclear-cytosolic shuttling, protein folding, and autophagy. The goals of this proposal are to 1) define the functional impact of HYPE-mediated AMPylation on HSC70 and 2) determine the impact of AMPylation on HSC70’s nuclear-cytosolic shuttling mechanism. Ultimately, we aim to define how a novel post-translational modification (PTM), AMPylation, regulates HSC70 function in proteostasis and cardiovascular diseases. Advancing our knowledge of the mechanisms that control HSC70 function is critical to identify novel avenues to therapeutic strategies that capitalize on restoring HSC70 regulation.

项目概要冠心病，也称为缺血性心脏病（IHD），是全世界死亡的主要原因。 IHD 患者反复出现心脏应激会导致心脏中错误折叠的蛋白质增加。为了应对这种细胞应激的急性发作，心肌细胞中的热休克蛋白 (HSP) 上调并帮助恢复蛋白质稳态 (proteostasis) 是必需的，热休克同源 71 kDa (HSC70)。在没有细胞应激的情况下，HSP70 分子伴侣位于细胞质中，这种 ATP 依赖性分子伴侣。 HSC70 主动重折叠、降解和解聚蛋白质对于细胞自噬也至关重要。保护心脏免受缺血后蛋白质错误折叠的回收/降解过程。 HSC70 功能与心脏病有关，尽管 HSC70 在细胞生理学中发挥着关键作用，调节核运输和控制 HSC70 不同功能的分子机制仍然存在未知。蛋白质 AMPylation 最近作为一种独特的 PTM 出现，通过以下方式调节 HSP70 家族伴侣：将腺苷单磷酸（AMP）添加到苏氨酸残基上该过程由哺乳动物催化。 AMPylase，HYPE。我的初步工作表明，HYPE 在两个位点上对 HSC70 进行 AMPylates，并且增加了 HSC70 的活性。细胞内的 AMPylation 水平也会阻止 HSC70 的核胞浆穿梭及其 ATPase I 活性。发现，与 HSC70 直系同源物 HSP-1 水平降低类似，AMPylation 增加会抑制线虫中自噬体的形成这些数据表明 HYPE 介导的 HSC70 的 AMPylation 抑制。其关键功能与维持蛋白质稳态相关，包括核-胞质穿梭、蛋白质折叠和自噬。该提案的目标是 1) 定义 HYPE 介导的 AMPylation 对 HSC70 的功能影响和 2) 确定 AMPylation 对 HSC70 核胞质穿梭机制的影响。定义新型翻译后修饰 (PTM) AMPylation 如何调节 HSC70 在蛋白质稳态中的功能增进我们对控制 HSC70 功能的机制的了解至关重要。寻找利用恢复 HSC70 调节的治疗策略的新途径。