Mechanisms and Regulation of Peroxiredoxins

过氧化还原蛋白的机制和调控

基本信息

批准号：
9121765
负责人：
LESLIE B POOLE
金额：
$ 35.92万
依托单位：
WAKE FOREST UNIVERSITY HEALTH SCIENCES
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-04-05 至 2020-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9121765
关键词：
Acetylation Active Sites Address Age-Months Aging Antibiotics Antioxidants Apoptosis Area Attention Biochemical Biological Models Biological Process Biology Calpain Catalysis Cell Differentiation process Cell Signaling Process Cells Chemicals Collection Communicable Diseases Crystallography Cysteine Degenerative Disorder Development Disease Disulfides Drug Targeting Electron Transport Enzymatic Biochemistry Enzymes Equilibrium Eukaryota Explosion Family Goals Growth Health Human Hydrogen Peroxide Immune system Impairment Infectious Agent Influentials Intervention Kinetics Knockout Mice Knowledge Literature Local Anti-Infective Agents Location Malignant Neoplasms Maps Measures Mediating Modeling Modification Molecular Conformation NADPH Oxidase Organism Oxidation-Reduction Oxidative Stress Paper Pathway interactions Peroxidases Peroxides Phosphorylation Phosphotransferases Play Post-Translational Protein Processing Prevention Property Proteins Published Comment Reaction Reducing Agents Regulation Research Role Salmonella typhimurium Science Second Messenger Systems Signal Pathway Signal Transduction Signaling Molecule Site Specificity Structure Surface TXN gene Therapeutic Agents Thermodynamics Time Toll-like receptors Toxin Virulence Factors Work X-Ray Crystallography Xanthomonas campestris base biophysical properties cell growth combat cytokine dimer electron donor human disease improved in vivo inhibitor/antagonist innovation insight killings member microbial nitration novel therapeutics oxidative damage pathogen peroxiredoxin public health relevance second messenger trend ultra high resolution virtual

项目摘要

DESCRIPTION (provided by applicant): Hydrogen peroxide is a toxin used by the human immune system to kill infectious organisms. It is now well accepted that it is also a common second messenger purposefully produced by NADPH oxidases as a part of eukaryotic signaling pathways crucial for human health such as those triggered by cytokines, many growth factors, and toll-like receptors of the innate immune system. Over the past 20 years, in part due to the work of the PIs of this proposal, a distinct, highly abundant family of peroxide-reducing enzymes, peroxiredoxins (Prxs), has gone from relative obscurity to become a major focus of redox biology research. Over these two decades, the PIs have developed expertise in Prx enzymology, biophysical characterization, and structure by characterizing Prxs from various organisms, especially using the peroxiredoxin AhpC of Salmonella typhimurium as a primary model system. Studies of Prxs are important both because Prxs from human pathogens are targets for antibiotic development, and because mammalian Prxs are involved in regulating key signaling pathways, with a Prx1 knockout mouse developing many forms of cancer by nine months of age. In 2003, we discovered that the mobility of protein segments packing near the active site is a key determinant of the sensitivity of Prxs to inactivation by peroxide-mediated hyperoxidation, and we proposed the "floodgate hypothesis" for how this sensitivity to inactivation would benefit organisms, like humans, where hydrogen peroxide is used as a signaling molecule: the antioxidant properties of the Prxs would be switched off at the right times and places to allow for a controlled local accumulation of peroxide. Since that time, additional posttranslational modifications (PTMs) have been shown to regulate the function of human Prxs. Given the importance of Prxs as microbial pathogenicity factors, for combating oxidative stress, and for regulating cell growth and differentiation in human cells, we propose here to address areas of Prx research where the biggest open questions remain. In Aim 1, we will deepen our understanding of key determinants of catalysis and of sensitivity toward hyperoxidation by investigating the biophysical and functional effects of four physiologically relevant PTMs on human Prx activity. In Aim 2, we develop a new Prx `model system' suitable for both NMR and crystallographic studies that will provide an unprecedented ability to measure and correlate dynamic features with structure and function. In Aim 3, we will advance knowledge of the poorly studied, but often rate-limiting, Prx reduction reaction, evaluating for several key Prxs how specificity and efficiency depend on oligomeric state, modification status, and location of a second (resolving) cysteine. We will also map out interaction interfaces by crystallography and/or NMR. These efforts will address areas important to the function and regulation of Prxs which have not yet received sufficient attention in spite of their importance, leading to a new level of understanding through which medically-and biologically-relevant interventions could be envisioned.

描述（适用提供）：过氧化氢是人类免疫系统使用的毒素来杀死传染性组织。现在，它也是NADPH氧化物作为对人类健康至关重要的真核信号传导途径的一部分（例如由细胞因子触发的，许多生长因子以及先天性免疫系统的Toll样受体触发的真核信号传导途径）的一部分，这也是公认的。在过去的20年中，部分原因是该提案的PI工作，这是一个独特的，高度丰富的过氧化物降解酶，过氧氧蛋白（PRXS），已经从相对的晦涩中转变为氧化还原生物学研究的主要重点。在这二十年的时间里，PIS通过表征来自各种生物体的PRX，尤其是使用Typhimurium沙门氏菌的过氧蛋白氧化物AHPC作为主要模型系统，在PRX酶学，生物物理表征和结构方面发展了专业知识。 PRX的研究很重要，因为来自人类病原体的PRX是抗生素发育的靶标，并且因为哺乳动物PRX参与调节关键信号通路，PRX1敲除小鼠在9个月大的年龄较高的PRX1基因敲除小鼠。 2003年，我们发现，在活跃部位附近蛋白质片段的迁移性是PRX对通过过氧化物介导的高氧化而灭活的敏感性的关键，我们提出了“洪流假说”，以使这种敏感性对失活的敏感性如何受益于人类的生物，例如，在某些人中，在某些人中，在某些人中，将其遗传性地呈氧化物呈氧化物，这些杂物是氧化物的特性。在适当的时间和地点关闭，以允许受控的过氧化局部积累。自那时以来，已显示出其他翻译后修饰（PTM）可以调节人PRX的功能。鉴于PRX作为微生物致病因素的重要性，对氧化应激以及控制人类细胞的细胞生长和分化的重要性，我们在这里建议解决最大的开放问题仍然存在的PRX研究领域。在AIM 1中，我们将通过研究四个物理相关的PTM对人PRX活性的生物物理和功能效应，从而加深对催化关键决定者和对高氧化的敏感性的理解。在AIM 2中，我们开发了一种适用于NMR和晶体学研究的新PRX“模型系统”，该研究将提供前所未有的能力，以测量和将动态特征与结构和功能相关联。在AIM 3中，我们将促进对所研究不良但经常限制的PRX减少反应的了解，评估几种关键PRX的特异性和效率如何依赖于寡聚状态，修改状态以及第二个（解决）半胱氨酸的位置。我们还将通过晶体学和/或NMR绘制交互接口。这些努力将解决对PRX的功能和调节重要的领域，尽管其重要性，这些领域尚未得到足够的关注，从而导致了新的理解水平，可以通过这种理解来设想与生物学和生物学相关的干预措施。