Elucidating the role of TSR glycosylation in Plasmodium parasites

阐明 TSR 糖基化在疟原虫寄生虫中的作用

基本信息

批准号：
10176392
负责人：
Kristian Edward Swearingen
金额：
$ 84.4万
依托单位：
INSTITUTE FOR SYSTEMS BIOLOGY
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-06-01 至 2025-05-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10176392
关键词：
Adhesives Amino Acid Substitution Antimalarials Binding Catalogs Cell surface Cell-Matrix Junction Cells Cessation of life Chordata Culicidae Data Defect Development Disease Extracellular Matrix Fucose Fucosyltransferase Goals Human In Vitro Individual Infection Intervention Invaded Life Cycle Stages Link Malaria Mannose Mannosyltransferases Mass Spectrum Analysis Membrane Proteins Methods Modification Mutation Nematoda Oocysts Parasites Plasmodium Plasmodium falciparum Plasmodium vivax Play Polysaccharides Protein Glycosylation Proteins Proteoglycan Recombinant Proteins Recombinants Research Research Design Role Serine Site Sporozoites System Tertiary Protein Structure Testing Threonine Thrombospondins Time Transgenic Organisms Tryptophan Ursidae Family Vaccine Design Virulence Virulence Factors Work cell motility fitness global health glycosylation glycosyltransferase heparin proteoglycan improved in vivo infected vector rodent insight interest parasite invasion prevent protein function

项目摘要

PROJECT SUMMARY _____ Thrombospondin type-1 repeats (TSRs) are small, adhesive protein domains that are found in phyla as diverse as chordates, nematodes, and apicomplexans. TSR-bearing proteins, which are typically localized to the cell surface or extracellular matrix, serve a wide variety of functions, including cell attachment and motility. TSRs are usually glycosylated at highly conserved motifs wherein tryptophans may be modified with a C-linked mannose and a conserved serine or threonine residue may be modified with an O-linked fucose. Parasites of the genus Plasmodium, the causative agent of the disease malaria, express ten conserved TSR- bearing proteins at various stages throughout their life cycle. Disrupting any one of them severely disrupts or halts parasite development. The most extensively studied of the TSR-bearing proteins are the sporozoite surface proteins CSP and TRAP. It has been shown that the TSRs in these proteins contain motifs that bind to proteoglycans and thus play a role in parasite invasion of host cells. We have recently used mass spectrometry to demonstrate for the first time that the TSRs of CSP and TRAP are glycosylated in vivo. This discovery revealed a gap in the understanding of these otherwise well-studied invasins: TSR-bearing proteins are critical to the Plasmodium life cycle, yet nothing is known about the role of glycosylation in maintaining their function or virulence. We hypothesize that the O-fucosylation and C-mannosylation of TSRs in Plasmodium is required for the proper function of the glycosylated proteins, and we predict that preventing glycosylation of these proteins will inhibit their function and disrupt the Plasmodium life cycle. In order to test this hypothesis, we will first characterize the glycosylation status of all TSR-bearing proteins expressed in P. falciparum. We will then generate transgenic parasite lines with mutations that prevent modification of the TSRs of specific proteins in order to determine the role of glycosylation in the function of these virulence factors.

项目摘要_____ 血小板素型1型重复（TSR）是小的粘合蛋白结构域，在门中发现了多种多样作为弦，线虫和apicomplexans。含TSR的蛋白质，通常位于细胞表面或细胞外基质，具有多种功能，包括细胞附着和运动。 TSR 通常是在高度保守的基序中糖基化的，其中色氨酸可以通过C链接进行修饰甘露糖和保守的丝氨酸或苏氨酸残基可以用O连接的岩藻糖修饰。疟原虫属的寄生虫，疾病疟疾的病因，表达十个保守的TSR- 在整个生命周期中，在各个阶段都有蛋白质。破坏他们中的任何一个严重破坏或停止寄生虫的发展。最广泛研究的含TSR的蛋白是Sporozoite 表面蛋白CSP和陷阱。已经表明，这些蛋白质中的TSR包含结合的基序蛋白聚糖，因此在宿主细胞的寄生虫侵袭中发挥作用。我们最近使用了质谱法首次证明CSP和TRAP的TSR在体内被糖基化。这个发现揭示了对这些原本研究的侵入蛋白的理解的差距：含TSR的蛋白是至关重要的对于疟原虫生命周期，糖基化在维持其功能中的作用一无所知或毒力。我们假设需要适当糖基化蛋白的功能，我们预测预防这些蛋白质的糖基化将抑制它们的功能并破坏疟原虫生命周期。为了检验这一假设，我们将首先表征恶性疟原虫中表达的所有含TSR蛋白的糖基化状态。然后我们将生成转基因寄生虫线具有突变，可防止特定蛋白质的TSR修饰，以便为了确定糖基化在这些毒力因子功能中的作用。