RNA trafficking in mitochondria

线粒体中的RNA运输

• 批准号: 9321479
• 负责人: Carla M Koehler
• 金额: $ 29.18万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-01-01 至 2019-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9321479
• 关键词: Binding; Biogenesis; Bioinformatics; Biological Models; Biology; Cell Nucleus; Cells; Cellular biology; Code; Collaborations; Complex; Coupled; Cultured Cells; Cytomegalovirus; Cytosol; Data; Defect; Disease; Electron Transport; Embryo; Engineering; Enzymes; Eukaryota; Eukaryotic Cell; Exoribonucleases; Fibroblasts; Funding; Gatekeeping; Gene Expression; Genes; Genetic Transcription; Genome; Goals; Grant; Health; Hepatocyte; Human; Inherited; Inner mitochondrial membrane; Joints; Knock-out; Knowledge; Lead; Learning; Link; MELAS Syndrome; Mammalian Cell; Mammals; Manuscripts; Mediating; Membrane; Membrane Potentials; Membrane Proteins; Metabolic; Methods; MicroRNAs; Mitochondria; Mitochondrial DNA; Mitochondrial Diseases; Mitochondrial Matrix; Mitochondrial RNA; Molecular; Monitor; Mus; Mutation; Neurodegenerative Disorders; Nuclear; Nuclear Import; Organelles; Organism; PTGS1 gene; Paper; Pathway interactions; Point Mutation; Polyribonucleotide Nucleotidyltransferase; Process; Production; Protein Import; Proteins; Public Health; Publishing; RNA; RNA Interference; RNA Processing; RNA Sequences; RNA replacement; RNA, Ribosomal, 5S; RNase P; Reporter; Reporting; Research; Ribosomes; Signal Pathway; Signal Transduction; System; Transfer RNA; Translating; Translations; Yeasts; base; cohort; deafness; design; disease-causing mutation; fly; human disease; mitochondrial DNA mutation; mitochondrial genome; mitochondrial membrane; mouse model; nervous system disorder; next generation; trafficking; transcriptome sequencing; translation factor; viral RNA

Mitochondria are essential organelles for most eukaryotic cells. They provide diverse metabolic functions including the production of energy and specialized metabolites for biosynthetic processes. To assemble functional mitochondria, proteins and RNAs encoded by both the mitochondrial and nuclear genomes are required. In humans, at least 1,000 nuclear encoded proteins are imported into mitochondria, whereas only 13 proteins of the electron transport chain are encoded by mitochondrial genes. The translation of these few but essential mitochondrial encoded proteins requires mitochondrial ribosomes, translation factors, and transfer RNAs, a subset of which must be imported from the cytosol into the mitochondrial matrix. Recent studies in evolutionarily diverse organisms have shown that multiple RNAs are encoded within the nucleus and imported from the cytosol into mitochondria. Our overall understanding of mitochondrial import pathways for nuclear encoded proteins is quite detailed. By contrast, very little is known about the mitochondrial import mechanism for nuclear encoded RNAs or how this new knowledge can be used to deliver specific RNAs into mitochondria. The revised overall goals of our competitive R01 renewal application are to dissect the main and perhaps only pathway of RNA import into mitochondria and to develop strategies that target nuclear encoded RNAs to mitochondria in reporter constructs and for the treatment of diseases caused by mutations of mitochondrial DNA (mtDNA). In separate studies, we will identify the cohort of RNAs that are imported into mitochondria using next generation RNA-Seq and coupled bioinformatics approaches. Previously, we reported studies that showed that the RNA processing enzyme polynucleotide phosphorylase (PNPase) is unexpectedly localized to the mitochondrial intermembrane space (IMS), where it functions as a gatekeeper for nuclear encoded RNAs that are imported from the cytosol. Interestingly, PNPase is only present in the genomes of organisms such as flies, worms, and mammals, suggesting that its functions are limited to higher eukaryotes. To accomplish our revised proposal goals that retain the original essence of the project, we have identified two specific study aims. In Aim 1, additional regulatory components beyond PNPase for the import of nuclear encoded RNAs will be identified. In Aim 2, reporter and corrective nuclear encoded RNA constructs will be engineered to determine the RNA sequence and structural requirements of the RNA import machinery and to develop strategies to treat diseases caused by mutations in mtDNA. For these studies we will take advantage of different model systems that we have established to manipulate PNPase levels and activities. In addition to increasing our fundamental knowledge about the mechanisms of RNA import into mitochondria and learning the rules for manipulating this RNA import pathway, our renewal application may have a broad impact on public health because our approach could provide a method to ameliorate or possibly cure dozens of human diseases caused by mtDNA mutations.

线粒体是大多数真核细胞的必需细胞器。他们提供多种代谢功能 包括生物合成过程的能量和专业代谢产物的产生。组装 线粒体和核基因组编码的功能性线粒体，蛋白质和RNA是 必需的。在人类中，至少有1,000个核编码蛋白被进口到线粒体中，而只有13个 电子传输链的蛋白质由线粒体基因编码。这几个的翻译 必需的线粒体编码蛋白需要线粒体核糖体，翻译因子和转移 RNA，其子集必须从细胞质中导入到线粒体基质中。最近的研究 进化上多样的生物表明，多个RNA被编码在细胞核内并导入 从细胞质到线粒体。我们对核线粒体进口途径的总体理解 编码的蛋白质非常详细。相比之下，线粒体进口机制知之甚少 用于核编码的RNA或如何使用这种新知识将特定的RNA传递到线粒体中。 我们竞争性R01更新应用程序修订的总体目标是剖析主要目标， 也许只有RNA进口到线粒体的途径，并制定针对核编码的策略 RNA至线粒体在记者构建体中以及因由突变引起的疾病的治疗 线粒体DNA（mtDNA）。在单独的研究中，我们将确定进口到 线粒体使用下一代RNA-Seq和耦合的生物信息学方法。以前，我们报道 研究表明RNA加工酶多核苷酸磷酸化酶（PNPase）意外 位于线粒体膜间空间（IMS），在该线粒体膜间空间（IMS）充当核的守门人 从细胞质导入的编码RNA。有趣的是，PNPase仅存在于 果蝇，蠕虫和哺乳动物等生物，表明其功能仅限于更高的真核生物。 为了实现我们保留该项目原始本质的修订的提案目标，我们已经 确定了两个具体的研究目的。在AIM 1中，PNPase以外的其他监管组件进口 将确定核编码的RNA。在AIM 2中，记者和矫正核编码的RNA构建体将 设计以确定RNA进口机械的RNA序列和结构要求和结构要求 制定治疗由mtDNA突变引起的疾病的策略。对于这些研究，我们将接受 我们已经建立的不同模型系统的优势来操纵PNPase水平和活动。 除了增加我们对RNA进口机制的基本知识之外 线粒体和学习操纵这种RNA进口途径的规则，我们的续签应用可能 对公共卫生有广泛的影响，因为我们的方法可以提供一种改善或可能的方法 治愈数十种由mtDNA突变引起的人类疾病。