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

• 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
• 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

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.

项目摘要 冠心病，也被称为缺血性心脏病(IHD)，是全球主要的死亡原因。 IHD患者反复出现心脏应激会导致他们心脏中错误折叠的蛋白质增加。在……里面 作为对这种急性细胞应激的反应，热休克蛋白S在心肌细胞中表达上调 并有助于恢复蛋白质平衡(蛋白质平衡)。热休克同源蛋白71 kDa(HSC70)是一种必需的， 位于胞浆中的HSP70分子伴侣，在没有细胞压力的情况下。这种依赖于ATP的伴侣 主动折叠、降解和解聚蛋白质。HSC70对自噬也是至关重要的，自噬是一种细胞 循环/降解过程，保护心脏免受缺血后错误折叠的蛋白质的影响。受损的 HSC70的功能与心脏病有关，然而，尽管HSC70在细胞生理学中起着关键作用， 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AMP化是最近出现的一种独特的PTM，它通过 将一磷酸腺苷(AMP)加到苏氨酸残基上。这个过程是由哺乳动物催化的 AMPylase，炒作。我的初步工作显示，在两个网站上炒作AMPylates HSC70，并增加了 细胞AMP化水平阻止HSC70的核-胞质穿梭及其ATPase活性。我也是 发现，与HSC70同源HSP-1水平降低类似，AMP化增加抑制了 线虫自噬小体的形成。这些数据表明，炒作介导的HSC70的AMP化抑制了 它与维持蛋白稳定相关的关键功能，包括核-胞质穿梭，蛋白质 折叠和自噬。 这项提案的目标是1)确定炒作介导的AMP化对HSC70和HSC70的功能影响 2)确定AMP化对HSC70‘S核质穿梭机制的影响。最终，我们的目标是 明确一种新的翻译后修饰(PTM)，AMP化，如何在蛋白平衡中调节HSC70的功能 和心血管疾病。提高我们对控制HSC70功能的机制的了解是至关重要的 确定利用恢复HSC70调控的治疗策略的新途径。