Defining the Connections between Respiratory Chain Structure and Oxidative Stress

定义呼吸链结构与氧化应激之间的联系

基本信息

批准号：
8705536
负责人：
Matthew Escobar
金额：
$ 11.1万
依托单位：
CALIFORNIA STATE UNIVERSITY SAN MARCOS
依托单位国家：
美国
项目类别：
财政年份：
2008
资助国家：
美国
起止时间：
2008-08-01 至 2016-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8705536
关键词：
ATP Synthesis Pathway Aerobic Affect Age Aging Alzheimer&apos s Disease Ammonium Animals Antioxidants Arabidopsis Automobile Driving Biochemical Pathway Biochemistry Bioenergetics Biological Models Biology Bypass Cell Death Cell physiology Cells Cellular biology Characteristics Complex DNA Development Diabetes Mellitus Drosophila genus Electron Transport Electron Transport Complex III Electrons Environment Eukaryotic Cell Experimental Models Extravasation FMN reductase Funding Gene Expression Profile Gene Expression Regulation Gene Family Global Change Goals Health Homeostasis Human Hydrogen Peroxide Lead Link Lipids Longevity Maintenance Malignant Neoplasms Measures Mediating Metabolism Mitochondria Modeling Mouse-ear Cress NADH dehydrogenase (ubiquinone)Neurodegenerative Disorders Nitrogen Organism Outcome Oxidation-Reduction Oxidative Stress Parkinson Disease Pathology Pathway interactions Plant Model Plants Play Principal Investigator Process Production Proteins RNA Interference RNAi vector Reactive Oxygen Species Research Respiratory Chain Role Signal Pathway Site Source Structure System Testing Transcript Transgenic Organisms Transgenic Plants United States National Institutes of Health Variant Vascular Plant Work alternative oxidase ammonium nitrate biological adaptation to stress design interest oxidation oxidative damage programs repaired respiratory respiratory enzyme vector

项目摘要

DESCRIPTION (provided by applicant): The mitochondrial electron transport chain (ETC) is central to the survival of all eukaryotic cells, driving the synthesis of ATP that fuels cellular bioenergetics. Despite its fundamental role, significant variation exists in the structure of the ETC in different organisms. Unlike the relatively simple ETC characteristic of higher animals, plants possess a complex, branched respiratory chain containing type II NAD(P)H dehydrogenases (ND) and alternative oxidases (AOX), which provide alternative pathways for electron flow. Several recent studies have suggested that these alternative respiratory enzymes may minimize "electron leakage" from the ETC, diminishing the production of damaging reactive oxygen species (ROS). ROS production and resulting oxidative stress are of significant biomedical interest, since oxidative damage appears to play a significant role in aging as well as a diverse array of pathologies, from Alzheimer's to diabetes. Notably, the progressive oxidative damage associated with aging in animals is absent in plants, and the expression of an ND in an animal system (Drosophila) decreases mitochondrial ROS production and increases lifespan. Thus, the overarching goal of this proposal is to define the relationship between ETC structure and ROS production/progressive oxidative damage. Toward this end, we plan to experimentally modify the plant ETC by using an inducible RNA interference vector to silence the AOX gene family, the NDinternal gene family, and the NDexternal gene family in the model plant species Arabidopsis thaliana. The resulting transgenic plants (independent AOX-silenced, NDin-silenced, and NDout-silenced lines) will allow the regulated suppression of distinct alternative respiratory pathways, creating intermediates between plant-type and mammalian-type respiratory chain configurations. To link these unique respiratory structures to quantifiable effects on cell physiology, we plan to measure ROS production, oxidative damage, and the size and oxidation state of cellular antioxidant pools in the transgenic lines. In addition, we will examine global changes in the transcriptomes of the transgenic lines in order to characterize how altered respiratory chain structure affects ROS-associated signaling pathways. This proposal expands and builds upon current NIH SCORE-funded research focused on the development of Arabidopsis as a model system to study basic cellular redox biology and oxidative damage. Overall, the proposed project will have a major impact on our fundamental understanding of mitochondrial- associated ROS production, a process which is central to both the basic field of cell biology and the maintenance of human health.

描述（由申请人提供）：线粒体电子传递链 (ETC) 对于所有真核细胞的生存至关重要，驱动 ATP 的合成，为细胞生物能量提供燃料。尽管 ETC 具有重要作用，但不同生物体中 ETC 的结构存在显着差异。与高等动物相对简单的 ETC 特征不同，植物拥有复杂的分支呼吸链，其中包含 II 型 NAD(P)H 脱氢酶 (ND) 和替代氧化酶 (AOX)，为电子流提供替代途径。最近的几项研究表明，这些替代呼吸酶可以最大限度地减少 ETC 的“电子泄漏”，从而减少有害活性氧 (ROS) 的产生。 ROS的产生和由此产生的氧化应激具有重要的生物医学意义，因为氧化损伤似乎在衰老以及从阿尔茨海默氏症到糖尿病等多种病理学中发挥着重要作用。值得注意的是，植物中不存在与动物衰老相关的进行性氧化损伤，并且动物系统（果蝇）中 ND 的表达会减少线粒体 ROS 的产生并延长寿命。因此，该提案的首要目标是定义 ETC 结构与 ROS 产生/进行性氧化损伤之间的关系。为此，我们计划通过使用诱导性RNA干扰载体对植物ETC进行实验性修饰，以沉默模式植物拟南芥中的AOX基因家族、NDinternal基因家族和NDexternal基因家族。由此产生的转基因植物（独立的 AOX 沉默、NDin 沉默和 NDout 沉默品系）将允许对不同的替代呼吸途径进行调节抑制，从而在植物型和哺乳动物型呼吸链配置之间产生中间体。为了将这些独特的呼吸结构与对细胞生理学的可量化影响联系起来，我们计划测量转基因系中ROS的产生、氧化损伤以及细胞抗氧化剂库的大小和氧化状态。此外，我们将检查转基因品系转录组的整体变化，以表征改变的呼吸链结构如何影响 ROS 相关信号通路。该提案扩展并建立在当前 NIH SCORE 资助的研究的基础上，该研究的重点是开发拟南芥作为研究基本细胞氧化还原生物学和氧化损伤的模型系统。总体而言，拟议的项目将对我们对线粒体相关 ROS 产生的基本理解产生重大影响，这一过程对于细胞生物学的基础领域和维护人类健康都至关重要。