Nonconventional mitochondrial ribosomes of malaria parasites

疟疾寄生虫的非常规线粒体核糖体

• 批准号: 9222483
• 负责人: Hangjun Ke
• 金额: $ 16.2万
• 依托单位: DREXEL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-08-01 至 2019-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9222483
• 关键词: Address; Anabolism; Antimalarials; Apicomplexa; Appearance; Artemisinins; Atovaquone resistance; Biogenesis; Biological Process; Blood; CRISPR/Cas technology; Catalytic RNA; Cell Nucleus; Cessation of life; Chemicals; Complex; Culicidae; Cytochrome bc1 Complex; Cytochromes b; Data; Development; Dihydroorotate dehydrogenase; Disease; Drug Targeting; Drug resistance; Electron Transport; Enzymes; Falciparum Malaria; Future; Generations; Genes; Genetic; Genome; Genomics; Goals; High Pressure Liquid Chromatography; Human; Immunologics; Infection; Insecta; Iron; Knock-out; Knowledge; Life; Light; Malaria; Maps; Mass Spectrum Analysis; Membrane Potentials; Messenger RNA; Mitochondria; Mitochondrial DNA; Mitochondrial Proteins; Mitochondrial RNA; Molecular Weight; Mutation; Northern Blotting; Nuclear; Organelles; Oxidative Phosphorylation; Parasites; Pathway interactions; Phylogenetic Analysis; Plasmodium falciparum; Production; Protein Biosynthesis; Protein Subunits; Proteins; Pyrimidine; RNA; Regulation; Research; Resistance; Ribosomal Proteins; Ribosomal RNA; Ribosomes; Side; Structure; Sulfur; System; Techniques; Therapeutic Intervention; Time; Transfer RNA; Transgenic Organisms; Translating; Translations; Ubiquinone; Uncertainty; Validation; aptamer; asexual; chemotherapy; combat; cytochrome c oxidase; drug discovery; experimental study; genetic variant; improved; inhibitor/antagonist; insight; knock-down; mitochondrial genome; mitochondrial membrane; new therapeutic target; novel; pathogen; pressure; rRNA Genes; tool; transcriptome sequencing; ubiquinol

Nonconventional mitochondrial ribosomes of malaria parasites Project summary The overall goal of this project is to investigate the structure and function of the mitochondrial ribosome (mitoribosome) in Plasmodium falciparum malaria parasites. The ribosome is a large-molecular-weight complex (~2 MDa) composed of RNAs and proteins that translates genomic information into proteins. Protein translation is a basic and pivotal biological process in all life forms. In malaria parasites, there are evidently three protein translation systems responsible for translating the genomes of the nucleus, the apicoplast and the mitochondrion. The mitoribosome in P. falciparum is phylogenetically and structurally highly divergent relative to the cytosolic and mitochondrial ribosomes of the human host, suggesting the parasite mitoribosome may prove to be an efficacious antimalarial drug target. The research in this proposal will dissect the components and investigate the biological functions of this machinery. Thus, this project would shed light on the structure and function of the ancient protein translational apparatus and expand our knowledge about ribosomal RNA (rRNA) function and protein synthesis in general. Moreover, this study would provide a basis for discovering novel antimalarial inhibitors targeting the mitochondrial protein translation. The mitochondrion of malaria parasites is an essential organelle throughout their complex lifecycle. It is responsible for several critical biosynthetic pathways, such as pyrimidine biosynthesis and iron-sulfur cluster biogenesis, and appears to be essential for energy production through oxidative phosphorylation in insect stages. Maintaining the mitochondrial electron transport chain (mtETC) and the membrane potential is absolutely essential for malaria parasites, and the cytochrome bc1 complex of the mtETC is a proven antimalarial drug target. However, we remain largely ignorant of the structure and function of the parasite mitoribosome, which translates cytochrome b and two subunits of the cytochrome c oxidase. The 6 kb mitochondrial DNA (mtDNA) in malaria parasites is the smallest organellar genome, only encoding three components of the mtETC and ~30 small pieces of fragmented rRNA genes. The discontinuity of the rRNA genes and the complete absence of tRNA genes in the genome have created some doubt regarding the existence of protein translation in this organelle for many years. To address the fundamental questions of malarial mitoribosome, my first aim is to dissect the protein subunits of this machinery through the combination of ribosome isolation and mass spectrometry. The rRNA content in mitoribosome will be characterized by high throughput small RNA-seq. The second aim is to prove that the parasite mitoribosome is functional and essential. Knockout and knock down studies will be carried out on three conserved ribosomal protein subunits. This study will provide information to fill an important scientific gap and offer unique opportunities for future therapeutic interventions.

疟原虫的非常规线粒体核糖体 项目摘要 本项目的总体目标是研究线粒体核糖体的结构和功能 （mitoribosome）在恶性疟原虫疟疾寄生虫中。核糖体是大分子量的 由RNA和蛋白质组成的复合物（~2 MDa），将基因组信息翻译成蛋白质。蛋白 翻译是所有生命形式中的一个基本和关键的生物学过程。在疟疾寄生虫中， 三个蛋白质翻译系统负责翻译细胞核，顶质体和 你好恶性疟原虫的丝裂体在遗传和结构上相对高度分化 与人类宿主的胞质和线粒体核糖体，这表明寄生虫线粒体核糖体可能 证明是一种有效的抗疟疾药物靶点。本提案中的研究将剖析 并研究这种机制的生物学功能。因此，该项目将揭示结构 和古代蛋白质翻译机构的功能，并扩大我们对核糖体RNA的知识 （rRNA）功能和蛋白质合成。此外，这项研究将为发现 靶向线粒体蛋白翻译的新型抗疟抑制剂。 疟疾寄生虫的细胞器是其复杂生命周期中必不可少的细胞器。是 负责几个关键的生物合成途径，如嘧啶生物合成和铁硫簇 生物发生，似乎是必不可少的能量生产通过氧化磷酸化在昆虫 阶段维持线粒体电子传递链（mtETC）和膜电位是 绝对是疟疾寄生虫所必需的，mtETC的细胞色素bc 1复合物是一种被证实的 抗疟药靶点。然而，我们仍然在很大程度上不了解的结构和功能， 寄生虫线粒体，其翻译细胞色素B和细胞色素c氧化酶的两个亚基。 疟原虫线粒体DNA（mitochondrial DNA，mtDNA）是疟原虫中最小的细胞器基因组，仅编码 mtETC的三种组分和约30个小片段的rRNA基因。的不连续性 rRNA基因和基因组中完全不存在tRNA基因引起了人们对它的一些怀疑。 蛋白质翻译在这个细胞器中存在多年。 为了解决疟疾线粒体的基本问题，我的第一个目标是解剖蛋白质亚基 通过核糖体分离和质谱分析的结合来研究这种机制。核糖体RNA含量 线粒体将通过高通量小RNA-seq来表征。第二个目的是证明 寄生虫线粒体是功能性的和必需的。敲除和敲除研究将在 三个保守的核糖体蛋白亚基。这项研究将提供信息，以填补一个重要的科学空白 并为未来的治疗干预提供独特的机会。