Thiol/Disulfide Redox Regulation of Heme Oxygenase-2

血红素加氧酶 2 的硫醇/二硫化物氧化还原调节

基本信息

批准号：
7985909
负责人：
Stephen Wiley Ragsdale
金额：
$ 54.45万
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：
2010
资助国家：
美国
起止时间：
2010-07-01 至 2014-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7985909
关键词：
Address Affect Affinity Azides Bacteria Biliverdin reductase Biliverdine Binding Binding Sites Biogenesis Blood C-terminal Calorimetry Carotid Body Catabolism Catalytic Domain Cell Respiration Cells Cysteine Cytoplasmic Structures Cytoplasmic Tail Disulfides Drug or chemical Tissue Distribution Electrophysiology (science)Embryo Environmental air flow Enzymes Exhibits Figs - dietary Fluorescence Gap Junctions Genetic Hand Heme Heme Iron Homeostasis Human Hypoxia Immunoprecipitation In Vitro Ion Channel Iron Kinetics Length Ligands Link Lipid Peroxidation Location Mammals Measurement Measures Membrane Metabolism Metals Methods NADPH-Ferrihemoprotein Reductase Neurons Organ Organism Oxidation-Reduction Oxygen Oxygenases Physiological Play Positioning Attribute Potassium Channel Process Property Protein Biosynthesis Protein Isoforms Proteins Regulation Research Respiration Respiratory System Reticulocytes Roentgen Rays Role Signal Transduction Source Structure Sulfhydryl Compounds System Testis Brain Titrations Variant Work adduct catalyst cell growth regulation circular magnetic dichroism cysteinylproline design electronic structure experience heme a heme oxygenase-1 heme oxygenase-2 in vivo insight kidney cell large-conductance calcium-activated potassium channels link protein oxidative damage public health relevance research study response vector

Address Affect Affinity Azides Bacteria Biliverdin reductase Biliverdine Binding Binding Sites Biogenesis Blood C-terminal Calorimetry Carotid Body Catabolism Catalytic Domain Cell Respiration Cells Cysteine Cytoplasmic Structures Cytoplasmic Tail Disulfides Drug or chemical Tissue Distribution Electrophysiology (science)Embryo Environmental air flow Enzymes Exhibits Figs - dietary Fluorescence Gap Junctions Genetic Hand Heme Heme Iron Homeostasis Human Hypoxia Immunoprecipitation In Vitro Ion Channel Iron Kinetics Length Ligands Link Lipid Peroxidation Location Mammals Measurement Measures Membrane Metabolism Metals Methods NADPH-Ferrihemoprotein Reductase Neurons Organ Organism Oxidation-Reduction Oxygen Oxygenases Physiological Play Positioning Attribute Potassium Channel Process Property Protein Biosynthesis Protein Isoforms Proteins Regulation Research Respiration Respiratory System Reticulocytes Roentgen Rays Role Signal Transduction Source Structure Sulfhydryl Compounds System Testis Brain Titrations Variant Work adduct catalyst cell growth regulation circular magnetic dichroism cysteinylproline design electronic structure experience heme a heme oxygenase-1 heme oxygenase-2 in vivo insight kidney cell large-conductance calcium-activated potassium channels link protein oxidative damage public health relevance research study response vector

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项目摘要

DESCRIPTION (provided by applicant): Heme oxygenase (HO) catalyzes the conversion of heme to biliverdin, CO, and iron. The two isoforms, HO1 and HO2, share similar physical and kinetic properties but exhibit different physiological roles and organ locations. The structures of the core catalytic domains of HO1 and HO2 are nearly superimposable and the major distinction between these HO isoforms is the occurrence of heme regulatory motifs (HRMs) in HO2 that are lacking in HO1. The HRMs play a regulatory role as a thiol/disulfide redox switch that we have shown to regulate interactions of HO2 with substrate (heme) and with a Ca++- activated high conductance potassium channel (the BK or Slopoke channel). Regulation of K+ flux across the membrane by the BK channel enables the O2 sensing function of the carotid body, which controls respiratory system ventilation in response to changes in the blood oxygen concentration. We recently demonstrated that the BK channel also contains a thiol/disulfide redox switch that regulates binding of heme, which has been shown to control its K+ channel activity. We plan to use spectroscopic, kinetic, genetic, crystallographic, NMR, and electrophysiology methods to determine how these thiol/disulfide redox switches (the HRMs in human HO2 and the CXXC motif in the human BK channel) affect the structure and function of and interactions between these functionally linked proteins. We will determine the redox states of the heme and HRMs in vitro and in vivo under various physiological conditions. We also will perform spectroscopic and electrophysiology measurements to determine the mechanism by which HO2 influences BK channel function. PUBLIC HEALTH RELEVANCE: Heme oxygenase (HO) is the only mammalian protein known to degrade heme and sits at the nexus of several major redox and metal regulatory systems. Unlike HO1, HO2 contains two Heme Regulatory Motifs (HRMs) that form a thiol/disulfide redox switch, which regulates binding of its substrate, heme. We propose to determine how thiol/disulfide redox switches on HO2 and on a functionally related interacting partner, a heme-regulated potassium channel, regulate their structures and functions.

描述（由申请人提供）：血红素加氧酶（HO）催化血红素到Biliverdin，CO和铁的转化。两种同工型HO1和HO2具有相似的物理和动力学特性，但具有不同的生理作用和器官位置。 HO1和HO2的核心催化结构域的结构几乎可叠加，这些HO同工型之间的主要区别是HO2中缺少HO2中的血红素调节基序（HRMS）。 HRMS作为硫醇/二硫键氧化还原开关的调节作用，我们已证明可以调节HO2与底物（Heme）的相互作用，以及与Ca ++活化的高电导钾通道（BK或Slopoke通道）。通过BK通道对K+通量的调节可以使颈动脉体的O2传感功能，该颈动脉体的O2感应功能，该功能控制呼吸系统通风，以响应血液氧浓度的变化。我们最近证明，BK通道还包含一个调节血红素结合的硫醇/二硫这氧化还原开关，该开关已显示出来控制其K+通道活性。我们计划使用光谱，动力学，遗传学，晶体学，NMR和电生理学方法来确定这些硫醇/二硫化物氧化还原开关（人HO2中的HRM和人类BK通道中的CXXC基序中的HRM）如何影响这些功能链接蛋白之间的结构和相互作用。我们将在各种生理条件下在体外和体内确定血红素和HRMS的氧化还原状态。我们还将执行光谱和电生理测量，以确定HO2影响BK通道功能的机制。公共卫生相关性：血红素加氧酶（HO）是唯一已知降解血红素并位于几种主要氧化还原和金属调节系统的Nexus的哺乳动物蛋白。与HO1不同，HO2包含两个血红素调节基序（HRMS），它们形成硫醇/二硫键氧化还原开关，可调节其底物的结合血红素。我们建议确定HO2上的硫醇/二硫键氧化还原开关如何以及功能相关的相互作用伴侣（血红素调节的钾通道）调节其结构和功能。