Antioxidant signaling by protein AMPylation

蛋白质 AMPylation 的抗氧化信号传导

基本信息

批准号：
10580729
负责人：
Vincent Scott Tagliabracci
金额：
$ 32.45万
依托单位：
UT SOUTHWESTERN MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-02-01 至 2025-01-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10580729
关键词：
Active Sites Adopted Aging Amino Acids Antioxidants Bacteria Biology Biotinylation Characteristics Cyclic AMP-Dependent Protein Kinases Cytoprotection DNA Damage Disease Enzymes Escherichia coli Eukaryota Goals Health Homeostasis Homologous Gene Human Human Biology In Vitro Intervention Ketoglutarate Dehydrogenase Complex Link Malignant Neoplasms Mammalian Cell Membrane Lipids Metabolism Mitochondria Mitochondrial Proteins Molecular Molecular Conformation Morbidity - disease rate Myocardial Infarction Names Nucleic Acids Oncogenic Oxidation-Reduction Oxidative Stress Oxidoreductase Pathologic Pathology Pathway interactions Patients Pattern Peripheral Vascular Diseases Phosphorylation Phosphotransferases Physiological Play Positioning Attribute Post-Translational Protein Processing Process Protein Kinase Proteins Public Health Reaction Reactive Oxygen Species Regulation Reperfusion Injury Role Selenium Selenocysteine Signal Pathway Signal Transduction Signaling Protein Stroke Structure Sulfhydryl Compounds Sulfur Symptoms Trees United States Work Yeasts analog biological adaptation to stress cell growth regulation cell injury diagnostic tool disulfide bond glutaredoxin human disease in vivo infancy innovation inorganic phosphate mortality neglect novel novel strategies pharmacologic protective pathway response selenol selenoprotein sensor therapeutic target virtual

项目摘要

Project Summary We have discovered that the predicted inactive pseudokinase selenoprotein O (SelO) adopts an atypical protein kinase fold, yet transfers AMP instead of phosphate to protein substrates in a post translational modification known as AMPylation. Our results illustrate the catalytic versatility of the protein kinase superfamily and suggest that AMPylation may be a more widespread post translational modification than previously appreciated. SelO localizes to the mitochondria, AMPylates proteins involved in cellular metabolism and redox biology, and appears to regulate an ancient and highly conserved cellular antioxidant signaling pathway. In higher eukaryotes, SelO contains the 21st genetically encoded amino acid, selenocysteine, which we propose functions as a redox sensor to regulate SelO activity in response to oxidative stress. Although reactive oxygen species are an obligatory part of human biology, elevated levels are characteristic of many disease states. For example, elevated reactive oxygen species can lead to DNA damage, which can initiate oncogenic transformation leading to cancer. Furthermore, alterations in redox homeostasis are implicated in the pathology of conditions such as stroke, heart attack, and peripheral vascular disease, all of which are major contributors to morbidity and mortality in United States. Therefore, a mechanistic understanding of the pathways that protect cells from oxidative stress could have major impacts on human health and disease. The major goal of this proposal is to determine the molecular mechanisms by which SelO-dependent AMPylation of mitochondrial proteins protects cells from oxidative stress and regulates redox homeostasis. As part of this work, we will determine the functional consequences of SelO-catalyzed AMPylation of a subset of substrates as well as the structural basis for the redox-dependent regulation of SelO activity. We anticipate that the results obtained herein will have the potential to define new paradigms of cellular regulation and redox signaling and could lead to innovative diagnostic tools or novel approaches for the treatment of human diseases.

项目概要我们发现预测的无活性假激酶硒蛋白 O (SelO) 采用非典型蛋白激酶折叠，但在翻译后修饰中将 AMP 而不是磷酸盐转移至蛋白质底物称为AMPylation。我们的结果说明了蛋白激酶超家族的催化多功能性，并表明 AMPylation 可能是比之前认识到的更广泛的翻译后修饰。塞尔奥定位于线粒体，AMPylates 参与细胞代谢和氧化还原生物学的蛋白质，并出现调节古老且高度保守的细胞抗氧化信号通路。在高等真核生物中，SelO 含有第 21 个基因编码氨基酸，硒代半胱氨酸，我们建议其作为氧化还原传感器调节 SelO 活性以应对氧化应激。尽管活性氧是人类生物学的重要组成部分，但水平升高是许多疾病状态。例如，活性氧含量升高会导致 DNA 损伤，从而导致 DNA 损伤。启动致癌转化，导致癌症。此外，氧化还原稳态的改变是与中风、心脏病和周围血管疾病等疾病的病理学有关，所有这是美国发病率和死亡率的主要原因。因此，机械性的理解保护细胞免受氧化应激的途径可能对人类健康和疾病产生重大影响。该提案的主要目标是确定 SelO 依赖性 AMPylation 的分子机制线粒体蛋白保护细胞免受氧化应激并调节氧化还原稳态。作为本次活动的一部分工作中，我们将确定底物子集 SelO 催化的 AMPylation 的功能后果：以及 SelO 活性氧化还原依赖性调节的结构基础。我们预计结果本文获得的成果将有可能定义细胞调节和氧化还原信号传导的新范例，可能会带来创新的诊断工具或治疗人类疾病的新方法。