Ribosome structure determination from Apicomplexan parasites

顶复门寄生虫的核糖体结构测定

• 批准号: 10726704
• 负责人: Melissa Leger-Abraham
• 金额: $ 25.43万
• 依托单位: HARVARD MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-05-24 至 2025-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10726704
• 关键词: Address; Affinity; Affinity Chromatography; Animal Diseases; Animals; Anti-Bacterial Agents; Antibiotics; Antiparasitic Agents; Apicomplexa; Area; Babesia; Babesiosis; Binding; Biology; Clinical; Complex; Cryoelectron Microscopy; Cytoplasm; Cytoplasmic Structures; Cytosol; Development; Disease; Drug resistance; Elements; Erythrocytes; Event; Fever; Foundations; Gene Expression; Gene Expression Regulation; Geographic Distribution; Geography; Goals; Growth; Hemagglutinin; Human; Immune system; Immunocompromised Host; Individual; Infection; Inorganic Phosphate Transporter; Laboratories; Life; Life Cycle Stages; Malaria; Membrane; Methods; Mitochondria; Molecular; Molecular Biology; Molecular Structure; NMR Spectroscopy; Names; Organelles; Organism; Parasites; Pathway interactions; Pharmaceutical Preparations; Plasmodium; Plasmodium falciparum; Preparation; Property; Protein Biochemistry; Protein Biosynthesis; Protocols documentation; Public Health; Research Proposals; Resolution; Ribosomal Proteins; Ribosomal RNA; Ribosomes; Structure; Symptoms; Therapeutic Intervention; Thick; Tick-Borne Diseases; Toxoplasma; Toxoplasmosis; Translations; Vaccines; Work; X-Ray Crystallography; antibiotic design; climate change; design; experience; experimental study; forest; human disease; improved; novel; novel therapeutics; particle; posttranscriptional; rational design; structural biology; suburb; targeted agent; targeted treatment; tick-borne

PROJECT SUMMARY/ABSTRACT The Apicomplexa phylum contains many parasites that infect and cause disease in humans and animals, including the agents that cause malaria, toxoplasmosis, and babesiosis. Babesia is a tick-borne intracellular parasite that causes severe to fatal diseases, with broadening geographic distribution because of climate change and increasing suburban developments in forested areas. There is no vaccine against human babesiosis, and the current therapies have limited efficacy. Considering the complex life cycle of Babesia species, their survival depends on the precise control of their gene expression, which is mostly regulated post-transcriptionally (e.g., during protein synthesis). Babesia species have a unique, non-photosynthetic organelle named apicoplast, derived from a secondary endosymbiotic event. In addition to having ribosomes in its cytoplasm and mitochondria, the apicoplast contains its own ribosomes. Little is known about the structure of these ribosomes, although they are thought to be highly simplified, with prokaryotic-like components. They are inhibited by antibacterial drugs that have some limited antiparasitic activity. The absence of a molecular structure of any apicoplast ribosomes limits the rational design of antibiotics with improved antiparasitic properties. In the first aim of this research proposal, we will establish a Babesia divergens strain expressing an hemagglutinin (HA)- tagged triose phosphate transporter on the outer membrane of the apicoplast. This strategy will allow the affinity purification of a high-quality organelle preparation, followed by the purification of apicoplast ribosomes. In the second aim, we will define the components of apicoplast ribosomes and determine their structure using cryo- electron microscopy (cryo-EM). Our goal is thus to elucidate the fundamental molecular machinery that apicomplexan parasites use to synthesize proteins in the highly specialized apicoplast organelle. Our work will lay the foundation for studies that interrogate these parasites' gene regulation mechanisms and help inspire the design of better antiparasitic agents.

项目摘要/摘要 Apicomplexa门包含许多寄生虫，这些寄生虫感染并引起人类和动物的疾病， 包括引起疟疾，弓形虫病和巴布西病的药物。巴贝西亚是tick虫的细胞内 导致严重至致命疾病的寄生虫，由于气候变化而扩大地理分布 并增加了森林地区的郊区发展。没有针对人类的疫苗， 当前的疗法的功效有限。考虑到巴贝斯物种的复杂生命周期，其生存 取决于其基因表达的精确控制，该基因表达大多在转录后受到调节（例如， 在蛋白质合成期间）。贝贝斯物种具有独特的，非光合合成器的细胞器，称为Apicoplast， 源自继发性内共生事件。除了其细胞质中核糖体和 线粒体，apicoplast包含其自身的核糖体。这些核糖体的结构知之甚少， 尽管人们认为它们具有高度简化，但具有原核生物样的成分。他们被抑制 抗寄生虫活性有限的抗菌药物。没有任何分子结构 Apicoplast核糖体限制了具有改善抗寄生虫特性的抗生素的合理设计。在第一个 这项研究建议的目的是，我们将建立表达血凝素（HA）的Babesia Divergens菌株 - 标记的三糖磷酸转运蛋白在尖体的外膜上。该策略将允许亲和力 高质量细胞器制备的纯化，然后纯化蛋白质成形棒核糖体。在 第二个目的，我们将定义Apicopollast核糖体的成分，并使用冷冻确定其结构 电子显微镜（冷冻EM）。因此，我们的目标是阐明基本的分子机制 Apicomplexan寄生虫用于合成高度专业化的pecopoplast细胞器中的蛋白质。我们的工作将 为研究这些寄生虫的基因调节机制的研究奠定基础 更好的抗寄生虫的设计。