Functional Analysis of Novel Components of the Toxoplasma Inner Membrane Complex

弓形虫内膜复合物新成分的功能分析

基本信息

批准号：
9533992
负责人：
Peter John Bradley
金额：
$ 38.11万
依托单位：
UNIVERSITY OF CALIFORNIA LOS ANGELES
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-08-01 至 2021-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9533992
关键词：
Animals Apical Biology Biotin Biotinylation CRISPR screen Cell membrane Cells Cellular biology Characteristics Coccidiosis Complex Cone Cytoskeletal Filaments Cytoskeleton Daughter Disease Eimeria tenella Elements Event Falciparum Malaria Family Human Immobilization In Vitro Invaded Knock-out Knowledge Lead Ligase Mass Spectrum Analysis Mediating Medical Membrane Methods Microtubules Morphology Motor Names Neospora caninum Organelles Parasites Parasitic infection Peripheral Play Process Proteins Proteome Reporting Role Series Shapes Streptavidin Surgical sutures System TimeLine Toxoplasma Toxoplasma gondii Toxoplasmosis Vesicle Virulence Xenopus oocyte cell motility choline transporter cohort daughter cell design experimental study fitness genome-wide in vivo insight member membrane biogenesis novel novel therapeutics obligate intracellular parasite parasite invasion pathogen protein complex protein function scaffold

项目摘要

PROJECT SUMMARY Toxoplasma gondii and related apicomplexan parasites contain a specialized organelle called the inner membrane complex (IMC) that plays essential roles in host cell invasion and daughter cell formation. Determining the precise functions of the IMC has been hampered by a limited understanding of its protein constituents, which have predominantly focused on the motor components of the glideosome that powers parasite motility and the family of alveolins that are embedded within the IMC cytoskeletal network underlying the flattened membrane vesicles of the organelle. We have recently overcome this gap in our knowledge using in vivo biotinylation (BioID) to identify over forty new IMC components, more than doubling the known IMC proteome. These new proteins have revealed a surprising level of compartmentalization within the organelle, with distinct components segregating to the cytoskeletal or membrane subregions of the apical cap, IMC body, or the recently discovered IMC sutures, which organize the IMC membranes into their characteristic rectangular plates. Analyses of a few of these proteins have revealed new important roles in controlling parasite shape, cellular division, and invasion. In this proposal, we will leverage our new cohort of IMC proteins to first provide a temporal and spatial understanding of how these components participate in the dynamic process of internal budding known as endodyogeny. This will reveal groups of proteins that function to assemble the IMC at specific steps of endodyogeny and also provide insight into the dynamic process of distinguishing maternal and daughter IMCs during division. We will then explore how the key IMC suture proteins ISC3 and ISC6 regulate proper IMC membrane biogenesis, parasite morphology and replication. Finally, we exploit the recent genome-wide CRISPR screen in Toxoplasma to focus on a subset of our new IMC proteins that are likely to play crucial roles within distinct suborganellar compartments of the organelle. Together, this project will fundamentally transform our understanding of the organization and function of the Toxoplasma IMC. As this organelle is parasite-specific and is not present in its human host, elucidating critical IMC components and their respective functions promises to reveal ideal targets for the design of novel therapies against T. gondii and other apicomplexan parasites.

项目摘要弓形虫Gondii和相关的Apicomplexan寄生虫包含一个专门的细胞器膜复合物（IMC）在宿主细胞侵袭和子细胞形成中起重要作用。确定IMC的精确功能已受到对其蛋白质的有限理解的阻碍成分主要集中在弹性的运动体的运动组件上寄生虫的运动和嵌入在IMC细胞骨架网络中的肺泡蛋白家族扁平的细胞器膜囊泡。最近，我们在我们的知识中克服了这一差距体内生物素化（Bioid）识别超过40个新的IMC组件，使已知的IMC增加了一倍以上蛋白质组。这些新蛋白质揭示了细胞器内的隔室化水平，具有不同的成分，将顶部盖，IMC主体的细胞骨架或膜子区域隔离或最近发现的IMC缝合线，将IMC膜组织成其特征矩形板。对其中一些蛋白质的分析揭示了控制中新的重要作用寄生虫形状，细胞分裂和入侵。在此提案中，我们将利用我们的新IMC蛋白首先为这些组件如何参与动态提供时间和空间理解内部发芽的过程被称为内部发育。这将揭示一组蛋白质在内部发育的特定步骤中组装IMC，还提供了对动态过程的见解在分区期间区分母亲和女儿IMC。然后，我们将探索密钥IMC缝合线蛋白质ISC3和ISC6调节适当的IMC膜生物发生，寄生虫形态和复制。最后，我们利用弓形虫的最近全基因组CRISPR屏幕专注于我们的新部分 IMC蛋白可能会在细胞器的不同亚科室内扮演至关重要的角色。该项目共同改变了我们对组织和功能的理解弓形虫IMC。由于该细胞器是寄生虫特异性的，并且不存在于其人类宿主中，因此阐明了关键 IMC组件及其各自的功能有望揭示新型设计的理想目标针对T. gondii和其他Apicomplexan寄生虫的疗法。