Aim32p; a novel multi-faceted protein in mitochondrial biogenesis

目标32p；

• 批准号: 9812708
• 负责人: Deepa Vinay Dabir
• 金额: $ 32.38万
• 依托单位: LOYOLA MARYMOUNT UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2023-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9812708
• 关键词: Affect; Anaerobic Bacteria; Binding; Biochemical; Biogenesis; Bioinformatics; C-terminal; Cells; Cellular Stress Response; Complex; Coupled; Cysteine; Cytosol; DNA Damage; Defect; Disease; Disulfide Linkage; Disulfides; Electron Transport; Electrons; Equilibrium; Experimental Models; Ferredoxin; Fumarates; Future; Goals; Health; Homeostasis; Human; Huntington Disease; Hypoxia; In Vitro; Inner Cell Mass; Institution; Iron; Iron-Binding Proteins; Knowledge; Lead; Learning; Lipids; Malignant Neoplasms; Mammalian Cell; Mitochondria; Mitochondrial Diseases; Mitochondrial Proteins; Molecular; Molecular Chaperones; Myopathy; Neuropathy; Organelles; Oxidants; Oxidation-Reduction; Oxidoreductase; Oxygen; Parkinson Disease; Pathology; Pathway interactions; Physiological; Physiological Processes; Physiology; Play; Process; Protein Import; Protein translocation; Proteins; Proteome; Public Health; Reaction; Recombinant Delta Chemokine; Reporting; Research; Respiratory Chain; Role; Saccharomyces cerevisiae; Saccharomycetales; Seminal; Series; Specific qualifier value; Structure; Students; Sulfhydryl Compounds; System; TXN gene; Translating; Twin Multiple Birth; Work; Yeasts; antioxidant enzyme; biological adaptation to stress; blastocyst; career; cytochrome c; defense response; experience; glutaredoxin 2; hands on research; human embryonic stem cell; hydroxyurea; in vivo; insight; mitochondrial dysfunction; non-Native; novel; oxidation; peroxiredoxin 2; prevent; protein complex; receptor; reproductive tract; sulfhydryl oxidase; undergraduate student; vector

PROJECT SUMMARY Mitochondrial biogenesis relies on efficient protein import as most mitochondrial proteins are imported via protein import pathways after synthesis in the cytosol. The mitochondrial intermembrane space (IMS) assembly (MIA) pathway that specifically imports proteins into the IMS is unique in that oxidative folding drives import and folding of target proteins. Specifically, a series of well-studied thiol-disulfide exchange reactions carried out by the two main components of the MIA pathway, namely Erv1 and Mia40 dictate vectorial translocation into the mitochondrial IMS. Studies have shown that several non-classical substrates, which do not possess the twin CX3C or CX9C motifs, utilize this pathway and importantly, connect the MIA pathway with other vital processes in the IMS, unrelated to oxidative folding. Hence, the MIA pathway is highly relevant in pathology of a spectrum of diseases such as, myopathies, neuropathies, Huntington’s disease, ALS and cancer. However, several unanswered questions remain. With the growing spectrum of substrates of this pathway, there is a need to understand the underlying molecular mechanisms. The MIA pathway must adapt to redox changes via interactions with antioxidant enzymes involved in reductive reactions in the IMS (thioredoxin 1, peroxiredoxin, and glutaredoxin 2). However, the role of these redox-balancing systems with the MIA machinery is not well known, and more notably, other reductive mechanisms may exist in the IMS. Finally, because MIA pathway is operational under anaerobic conditions, there must be additional electron acceptors. The goal of this undergraduate-driven proposal is to investigate the function of the newly identified Erv1-interacting protein, Aim32p in the experimental model, the budding yeast Saccharomyces cerevisiae. Preliminary studies strongly suggest that Aim32p is important for protein translocation across multiple translocons, stabilizes several native protein complexes, and belongs to a class of proteins, termed as thioredoxin-like ferredoxins (Fds); functions of which are unknown but range from electron shuttling to redox sensing. Because of its unique placement in the IMS, it is imperative to examine mechanisms by which Aim32p could affect multiple important mitochondrial processes of import, electron transfer, and have a regulatory role in redox. Three specific proposal aims that utilize a combination of biochemical and bioinformatic approaches will be undertaken: In Aim 1 role of Aim32p within the MIA pathway will be explored. In Aim 2, biochemical studies to validate if Aim32p is a Fe-S protein, identification of key cysteine residues, and pathways crucial for its cellular stress response, will be performed. Finally, Aim 3 will elucidate the Aim32p interaction network. Upon successful completion, this work will provide exciting new information on the function of a multi- faceted mitochondrial protein and advance our fundamental knowledge of the process of protein translocation. This research will have a broad impact on public health because these mechanistic studies will provide key insights into how defects in mitochondrial biogenesis lead to disease.

项目摘要 线粒体生物发生依赖于有效的蛋白，因为大多数线粒体蛋白是进口的 通过蛋白导入途径在细胞质中合成后。线粒体膜间空间（IMS） 专门将蛋白质进口到IMS的组装（MIA）途径是独一无二的 目标蛋白的导入和折叠。具体而言，一系列研究充分的硫硫化物交换反应 由MIA途径的两个主要组成部分进行，即ERV1和MIA40决定了矢量 转移到线粒体IMS中。研究表明，有几种非古典基材 不具备双CX3C或CX9C图案，使用此途径，重要的是，将MIA途径连接起来 IMS中的其他重要过程与氧化折叠无关。因此，MIA途径在 多种疾病的病理学，例如肌病，神经病，亨廷顿氏病，ALS和 癌症。但是，仍然存在一些未解决的问题。随着底物的日益增长 途径，需要了解潜在的分子机制。 MIA途径必须适应 通过与参与IMS中反应减少的抗氧化酶相互作用（硫氧还蛋白）的氧化还原变化（硫氧还蛋白 1，过氧蛋白和谷蛋白2）。但是，这些氧化还原平衡系统与MIA的作用 机械不是众所周知的，更值得注意的是，IMS中可能存在其他减少的机制。最后， 由于MIA途径在厌氧条件下运行，因此必须有其他电子受体。 该本科驱动的建议的目的是研究新确定的 ERV1相互作用蛋白，实验模型中的AIM32P，出现的酵母菌酿酒酵母。 初步研究强烈表明，AIM32P对于多个蛋白质易位很重要 转运，稳定几种天然蛋白质复合物，属于一类蛋白质，称为 硫氧还蛋白样铁毒素（FDS）；其功能是未知的，但范围从电子穿梭到氧化还原 感应。由于其在IMS中的独特位置，必须检查AIM32P的机制 可能影响多个重要的进口，电子传输的线粒体过程，并具有调节作用 在氧化还原中。三个特定的建议旨在利用生化和生物学方法的结合 将进行：将探索AIM32P在MIA途径中的AIM 1角色。在AIM 2，生化 研究验证AIM32P是否为Fe-S蛋白，鉴定关键半胱氨酸残基以及对途径至关重要的研究 将进行其细胞应力反应。最后，AIM 3将阐明AIM32P交互网络。 成功完成后，这项工作将提供有关多种功能的令人兴奋的新信息 面积的线粒体蛋白质，并提高了我们对蛋白质易位过程的基本知识。 这项研究将对公共卫生产生广泛的影响，因为这些机械研究将提供关键 深入了解线粒体生物发生的缺陷如何导致疾病。