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

• 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
• 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' 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

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）：线粒体电子传输链（ETC）对于所有真核细胞的存活至关重要，驱动ATP的合成，从而助长了细胞生物能。尽管它具有基本作用，但在不同生物体的ETC结构中仍然存在显着差异。与较高动物的相对简单的特征不同，植物具有复杂的分支呼吸链，其中含有II型NAD（P）H脱氢酶（ND）和替代氧化酶（AOX），该酶为电子流提供了替代途径。最近的一些研究表明，这些替代呼吸酶可能会使ETC中的“电子泄漏”最小化，从而减少了破坏性活性氧（ROS）的产生。 ROS产生和产生的氧化应激具有显着的生物医学兴趣，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的各种病理学中起着重要作用。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，动物系统（果蝇）中ND的表达降低了线粒体ROS的产生并增加了寿命。因此，该提案的总体目标是定义ETC结构与ROS产生/进行性氧化损害之间的关系。为此，我们计划通过使用诱导的RNA干扰载体来实验修改植物等，以使AOX基因家族，Ndinentart Gene家族和Ndexternal Gene家族中的Ndextern基因家族沉默。由此产生的转基因植物（独立的AOX，NDIN中脱毛和NDOUT脱毛的线）将允许调节不同的替代呼吸道途径，从而在植物型和哺乳动物型呼吸链构型之间形成中间体。为了将这些独特的呼吸结构与对细胞生理的可量化作用联系起来，我们计划测量转基因线中细胞抗氧化剂池的大小和氧化状态的ROS产生，氧化损伤以及氧化状态。此外，我们将检查转基因线的转录组中的全局变化，以表征呼吸链结构改变如何影响ROS相关的信号通路。该提案扩大并建立在当前的NIH评分资助研究的基础上，重点是拟南芥作为研究基本细胞氧化还原生物学和氧化损害的模型系统的发展。总体而言，拟议的项目将对我们对线粒体相关的ROS产生的基本理解产生重大影响，这对于细胞生物学的基本领域和维持人类健康都是至关重要的。