Controlling monolysocardiolipin/cytochrome c peroxidase complexes in Barth syndrome

控制 Barth 综合征中的单溶心磷脂/细胞色素 C 过氧化物酶复合物

• 批准号: 10246269
• 负责人: Miriam L Greenberg
• 金额: $ 41.44万
• 依托单位: WAYNE STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-01 至 2023-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10246269
• 关键词: 3-Methylglutaconic aciduria type 2; Affect; Cardiolipins; Cell Line; Cell physiology; Cells; Cellular biology; Code; Complex; Computer Models; Cytochrome c Peroxidase; Disease; Engineering; Fatty Acids; Gene Mutation; Generations; Genetic; Genetic Diseases; Hemeproteins; Homo; Human; Hydrolysis; In Vitro; Knowledge; Life; Link; Lipid Biochemistry; Lipids; Liposomes; Magic; Mammalian Cell; Mass Spectrum Analysis; Mediating; Metabolic; Metabolism; Mitochondria; Modeling; Molecular; Molecular Biology; Mus; Mutation; Myoblasts; Myopathy; Neutropenia; Nonesterified Fatty Acids; Oxidation-Reduction; Oxides; Pathogenesis; Pathology; Pathway interactions; Peroxidases; Peroxides; Phospholipase; Phospholipids; Polyunsaturated Fatty Acids; Production; Property; Publishing; Reaction; Reactive Oxygen Species; Role; Technology; Testing; Time; Transacylase; Unsaturated Fatty Acids; Yeast Model System; Yeasts; base; cytochrome c; deacylation; design; experience; experimental study; in vivo; inhibitor/antagonist; innovation; interfacial; lipidomics; mitochondrial dysfunction; monolysocardiolipin; oxidation; oxidative damage; oxidized lipid; peroxidation; remediation; simulation; skeletal; solid state nuclear magnetic resonance

Cardiolipin (CL), the signature phospholipid of mitochondria, is required for optimal mitochondrial function and numerous cellular processes. The de novo synthesis of CL is followed by a unique remodeling pathway, which is characterized by cycles of phospholipase-mediated deacylation of CL to monolysocardiolipin (mCL), and reacylation of mCL by tafazzin (Taz) to form predominantly unsaturated CL species. Mutations in Taz cause the life-threatening genetic disorder, Barth syndrome (BTHS), highlighting the significance of CL remodeling. While it is clear that Taz deficiency leads to accumulation of mCL, the mechanism linking defective CL remodeling to the pathology in BTHS is not known. An increase in reactive oxygen species (ROS), a feature of Taz-deficient cells, has been implicated in BTHS pathogenesis. However, detailed redox lipidomic analyses of oxidized species of mCL and CL (mCLox and CLox) in the context of CL remodeling have not been performed. Our preliminary and published studies show that CL and mCL form complexes with the intermembrane space hemoprotein, cytochrome c (cyt c), converting it to a potent peroxidase that generates mCLox and CLox. The proposed study will test the innovative hypothesis whereby aberrant CL remodeling along with peroxidation by mCL/cyt c complexes leads to a vicious metabolic cycle of CL/mCL oxidation in BTHS. Our approach combines our expertise and experience in genetics, molecular biology, and cell biology (Greenberg lab) with innovative approaches in mass spectrometry technologies, oxidative lipidomics, and biochemistry of lipids (Kagan lab). Aim 1 will test the working hypothesis that peroxidation by mCL/cyt c is exacerbated by Taz deficiency. Aim 2 will utilize solid-state NMR and computational modeling to rigorously characterize mCL/cyt c complexes and identify properties resulting in gain of peroxidase activity. We expect these studies to provide the first detailed characterization of the role of CL remodeling in generating and eliminating mCLox/CLox.

心磷脂（CL）是线粒体的标志性磷脂，是最佳线粒体功能和许多细胞过程所必需的。CL的从头合成之后是独特的重塑途径，其特征在于磷脂酶介导的CL脱酰化为单溶血心磷脂（mCL），以及tafazzin（Taz）再酰化mCL以形成主要不饱和CL物质的循环。Taz突变导致危及生命的遗传性疾病Barth综合征（BTHS），突出了CL重塑的重要性。虽然很明显，Taz缺乏导致mCL的积累，但将缺陷CL重塑与BTHS病理学联系起来的机制尚不清楚。活性氧（ROS）的增加，Taz缺陷细胞的一个特征，已牵连BTHS发病机制。然而，尚未在CL重塑背景下对mCL和CL的氧化物质（mCLox和CLox）进行详细的氧化还原脂质组学分析。我们的初步和已发表的研究表明，CL和mCL与膜间空间血红素蛋白，细胞色素c（cyt c）形成复合物，将其转化为一种有效的过氧化物酶，产生mCLox和CLox。拟议的研究将测试的创新假设，即异常CL重塑沿着与过氧化作用的mCL/细胞色素c复合物导致的恶性代谢循环的CL/mCL氧化BTHS。我们的方法结合了我们在遗传学，分子生物学和细胞生物学（Greenberg实验室）方面的专业知识和经验，以及质谱技术，氧化脂质组学和脂质生物化学（Kagan实验室）的创新方法。目的1将测试的工作假设，由mCL/细胞色素c的过氧化作用是由Taz缺乏加剧。目标2将利用固态NMR和计算建模来严格表征mCL/cyt c复合物，并确定导致过氧化物酶活性增加的性质。我们期望这些研究提供CL重塑在产生和消除mCLox/CLox中的作用的第一个详细表征。