Diversity Supplement for Elucidating the trafficking mechanisms of effector proteins to the Plasmodium infected red blood cell

用于阐明效应蛋白向疟原虫感染的红细胞运输机制的多样性补充

• 批准号: 10077624
• 负责人: Vasant Muralidharan
• 金额: $ 6.42万
• 依托单位: UNIVERSITY OF GEORGIA
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-01-05 至 2022-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10077624
• 关键词: Affect; Antimalarials; Asparagine; Binding; Biochemical; Biological Assay; Biological Models; Biological Process; Biotin; Biotinylation; Blood Vessels; Blood capillaries; Brain; CRISPR/Cas technology; Catalytic Domain; Cell Communication; Cell membrane; Cells; Cellular Membrane; Cessation of life; Clinical; Coagulation Process; Complement; Complex; Cytoplasm; Development; Disease; Drug Targeting; Drug resistance; Endoplasmic Reticulum; Endothelial Cells; Erythrocytes; Eukaryota; Event; Flow Cytometry; Genes; Genetic; Genome; Glycine decarboxylase; Glycoproteins; Goals; Growth; Habitats; Home environment; Human; Immunofluorescence Immunologic; Infection; Label; Lead; Life Cycle Stages; Ligase; Link; Malaria; Malaria Vaccines; Membrane; Metabolism; Methods; Modification; Molecular; Movement; Mutation; Nutrient; Oligosaccharides; Orthologous Gene; Parasites; Parasitic Diseases; Pathway interactions; Permeability; Plasmodium; Plasmodium falciparum; Plasmodium falciparum genome; Polysaccharides; Process; Property; Protein Export Pathway; Protein Glycosylation; Proteins; Proteome; Research; Resistance; Resistance development; Role; Side; Site; Sum; Testing; Time; Usher Proteins; asexual; base; conditional mutant; data acquisition; drug development; experimental study; glycosylation; human disease; mutant; novel therapeutics; obligate intracellular parasite; parent grant; programs; protein function; protein transport; resistant strain; screening; trafficking; whole genome

RESEARCH SUMMARY [PARENT GRANT] Plasmodium falciparum is a deadly human parasite that causes malaria and is responsible for nearly 450,000 deaths every year. Malaria is endemic in large regions of the world, home to about 4 billion people and it affects ~250 million people annually. There are no effective vaccines against malaria and antimalarial drugs are the mainstay of treatment. At this time, the parasite has gained resistance to all clinically available antimalarial drugs and these drug resistant strains are spreading throughout the world, threatening all the progress that has been made against this disease in the last decade. Therefore, it is imperative that we constantly generate new drugs and identify potential drug targets to stay ahead of this nefarious disease. The clinical manifestations of this devastating parasitic disease, including death, are caused by the growth of P. falciparum within the host red blood cell (RBC). To build a suitable habitat for growth inside RBCs, the malaria parasite completely transforms the host cell. It changes the metabolism of the RBC, makes the RBC more rigid such that it is harder for the infected RBC to pass through capillaries, modifies the RBC membrane to allow for favorable movement of nutrients, and alters the binding properties of the RBC so that the infected cell can bind to the endothelial cells lining blood vessels. The sum of these changes leads to disease and death, for instance, binding of the P. falciparum infected RBC to endothelial cells can clog blood vessels in the brain leading to clots that eventually result in death. The subjugation of the infected RBC is accomplished through the action of several hundred proteins that the parasite transports to the host cell via poorly understood mechanisms. The export of parasite effector proteins is essential for transforming the RBC and therefore, for causing disease. Parasite effector proteins that are synthesized in the parasite cytoplasm need to be transported across three or four cellular membranes in order to reach their site of action in the host RBC. The molecular mechanisms that recognize, sort, and transport these parasite effectors to the infected RBC remain to be identified. The proposed studies aim to unravel the molecular processes that govern key early events that set parasite effectors on the path to the host RBC. We will pursue two aims to accomplish this goal. First, we will generate conditional mutants of proteins in the endoplasmic reticulum of the parasite that are potentially required for export of parasite effectors. The mutants will be analyzed using genetic, cellular, and biochemical approaches to determine their roles in the export of parasite proteins. Second, we will take an unbiased interactome screening approach that uses a proximity-based labeling approach and discover proteins that usher exported proteins to their site of action in the host RBC. Attaining the objectives of the research program will reveal key and unique protein trafficking mechanisms of P. falciparum that may be targeted for antimalarial drug development.

研究摘要[家长资助] 恶性疟原虫是一种致命的人类寄生虫，可引起疟疾，导致近 45 万人死亡 每年都有死亡人数。疟疾在世界大部分地区流行，大约有 40 亿人口，它影响到 每年约 2.5 亿人。没有有效的疟疾疫苗，抗疟药物是 治疗的支柱。此时，寄生虫已经对所有临床可用的抗疟药物产生了耐药性 这些耐药菌株正在全世界蔓延，威胁着已经取得的所有进展 过去十年来针对这种疾病做出了努力。因此，不断研发新药势在必行。 并确定潜在的药物靶标，以领先于这种邪恶的疾病。本病的临床表现 毁灭性的寄生虫病，包括死亡，是由恶性疟原虫在宿主红体内的生长引起的 血细胞（红细胞）。为了在红细胞内建立适合生长的栖息地，疟疾寄生虫彻底转变 宿主细胞。它改变红细胞的新陈代谢，使红细胞变得更坚硬，从而更难 受感染的红细胞通过毛细血管，改变红细胞膜以允许红细胞有利地运动 营养物质，并改变红细胞的结合特性，使受感染的细胞能够与内皮细胞结合 衬里血管。这些变化的总和会导致疾病和死亡，例如 P 的结合。 恶性疟原虫感染的红细胞和内皮细胞会堵塞大脑血管，最终导致血栓形成 结果导致死亡。对受感染红细胞的征服是通过数百名红细胞的行动完成的 寄生虫通过知之甚少的机制将蛋白质转运至宿主细胞。寄生虫出口 效应蛋白对于红细胞的转化至关重要，因此对于引起疾病至关重要。寄生效应器 在寄生虫细胞质中合成的蛋白质需要转运穿过三个或四个细胞 膜以到达宿主红细胞中的作用位点。识别的分子机制， 分类并将这些寄生虫效应物运输到受感染的红细胞仍有待鉴定。拟议的研究 旨在揭示控制关键早期事件的分子过程，这些事件使寄生虫效应器走上 宿主红细胞。为了实现这一目标，我们将追求两个目标。首先，我们将生成条件突变体 寄生虫内质网中的蛋白质，可能是寄生虫效应子输出所必需的。 将使用遗传、细胞和生化方法对突变体进行分析，以确定它们在 寄生虫蛋白的输出。其次，我们将采取一种公正的相互作用组筛选方法，该方法使用 基于邻近性的标记方法并发现将蛋白质引导至其作用位点的蛋白质 宿主红细胞。实现研究计划的目标将揭示关键且独特的蛋白质贩运 恶性疟原虫的机制可能是抗疟药物开发的目标。