Mitochondrial Biogenesis in Health and Disease

项目摘要 线粒体允许我们的细胞使用氧化磷酸化（OXPHOS）作为一种高效的方式来产生 ATP内膜包埋的OXPHOS系统酶是由以下组成的多聚体复合物： 这些蛋白质来自两种不同的遗传来源，即核DNA和线粒体DNA。核编码 蛋白质在细胞质核糖体中合成并输入线粒体。那条蛇- 编码的蛋白质，通常是复合物的催化核心亚基， 核糖体影响这些过程的突变导致线粒体心肌病和脑肌病， 与神经退化、代谢疾病、癌症和衰老有关。 我们已经开发了一个科学研究计划，旨在了解分子机制， 这是双重遗传起源的线粒体复合体组装的基础。我们的计划包括深入 研究三组大分子结构的组装。(i)单个OXPHO的组装 酶，重点是MRC复合物IV或细胞色素c氧化酶（考克斯）的组装， MRC酶。(ii)MRC酶组装成称为超复合物的超分子结构， - 是的(iii)线粒体的组装和功能。 在每种情况下，我们将追求三个总体目标：（i）定义组装途径和组装顺序。 组件和辅基的并入;（ii）识别和表征组装因子 涉及，和（iii）披露监管装配检查点，检测损坏或异常折叠 组件，或协调合成或成熟的一个组件与其组装成复合物。 该提案中概述的研究将涉及酵母遗传学，使用基因编辑破坏人类细胞中的基因 策略，蛋白质复合物和组装中间体的冷冻-EM重建，以及 在酵母、人细胞系、分离的线粒体和纯化的天然和重组蛋白中的生物化学， 深入了解OXPHOS复合物，超复合物和线粒体组装因子的作用。的 分析生物发生过程的原理和组装因子的活动是生物合成的核心。 这对我们理解人类线粒体疾病的分子基础具有重要意义。 揭示了细胞宏观结构组装发生的机制， 标准条件和压力下仍然是现代科学的重大挑战之一， 和生物医学的观点。我们预计，我们的计划将继续有助于缩小我们的差距， 了解健康和疾病中的线粒体生物发生。

Project Summary Mitochondria allow our cells to use oxidative phosphorylation (OXPHOS) as a highly efficient way to generate ATP. The inner membrane-embedded OXPHOS system enzymes are multimeric complexes composed of proteins from two different genetic origins, namely the nuclear and the mitochondrial DNA. Nucleus-encoded proteins are synthesized in cytoplasmic ribosomes and imported into mitochondria. The mitochondrion- encoded proteins, usually catalytic core subunits of the complexes, are synthesized into distinct mitochondrial ribosomes. Mutations affecting these processes lead to mitochondrial cardio- and encephalo-myopathies and have been linked to neurodegeneration, metabolic disease, cancer, and aging. We have developed a scientific research program aiming to understand the molecular mechanisms underlying the assembly of mitochondrial complexes of dual genetic origin. Our program includes in-depth studies into the assembly of three sets of macromolecular structures. (i) Assembly of individual OXPHOs enzymes, with an emphasis on the assembly of MRC complex IV or cytochrome c oxidase (COX), the terminal MRC enzyme. (ii) Assembly of MRC enzymes into supramolecular structures known as supercomplexes and respirasomes. (iii) Assembly and function of the mitoribosome. In each case, we will pursue three general goals: (i) Define the assembly pathway/s and the order of incorporation of components and prosthetic groups; (ii) Identify and characterize the assembly factors involved, and (iii) Disclose regulatory assembly checkpoints, which detect damaged or abnormally folded components, or coordinate synthesis or maturation of one component with its assembly into the complex. Studies outlined in this proposal will involve yeast genetics, gene disruption in human cells using gene-editing strategies, cryo-EM reconstruction of protein complexes and assembly intermediates, and mechanistic biochemistry in yeast, human cell lines, isolated mitochondria and purified native and recombinant proteins to gain insight into the role/s of OXPHOS complex, supercomplex and mitoribosome assembly factors. The analysis of the principles of the biogenesis process and the activities of the assembly factors is of central importance for our understanding of the molecular basis of human mitochondrial disorders. Uncovering the mechanisms through which assembly of cellular macrostructures takes place in standard conditions and under stress remains one of the grand challenges of modern science from a biological and a biomedical perspective. We anticipate that our program will continue contributing to close the gap in our understanding of mitochondrial biogenesis in health and disease.