West African Centre for Cell Biology of Infectious Pathogens, Department of Biochemistry, Cell, and Molecular Biology, College of Basic and Applied Sciences, University of Ghana, Accra, Ghana.
Department of Parasitology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Accra, Ghana.
Front Cell Infect Microbiol. 2022 Aug 19;12:886728. doi: 10.3389/fcimb.2022.886728. eCollection 2022.
malaria is still an important disease in sub-Saharan Africa (sSA). Great strides have been made in its control spear-headed by artemisinin (ART)-based combination therapies (ACTs). However, concerns about the imminent spread of ART-resistant (ARTr) malaria parasites to sSA threaten gains already made. Attempts to mitigate this risk have highlighted the need to discover novel drug targets. Therefore, studies to deepen our understanding of the biology of are needed. The role of extracellular vesicles (EVs) in the biology of malaria parasites is not fully understood. Recently, the ART resistance-associated transcriptional profile has been reported to involve several biological processes connected to vesicular trafficking, proteotoxic stress, erythrocyte remodelling, and mitochondrial metabolism. We explored a role for EVs in developing the ARTr phenotype using bulk RNA sequencing of unsynchronized parasite cultures under untreated, 0.1% dimethyl sulfoxide and 700nM dihydroartemisinin treated conditions for six hours. As pathway and gene ontology analysis is limited in its curated knowledge repertoire on EVs biogenesis in , we used a modular (gene set) analysis approach to explore whether an EVs biogenesis module is associated with the ARTr phenotype in . We first generated well-defined EVs modules of interest and used statistical tools to determine differences in their expression among the parasite and treatment conditions. Then we used gene set enrichment analysis to determine the strength of the association between each EVs module of interest and the ARTr phenotype. This transcriptome-module phenotype association study (TMPAS) represents a well-powered approach to making meaningful discoveries out of bulk gene expression data. We identified four EVs module of interest and report that one module representing gene sets with correlated expression to PF3D7_1441800 - involved with EVs biogenesis in - is associated with the ARTr phenotype (R539T_DHA_treated versus R539T_untreated: normalized enrichment score (NES) = 1.1830174, FDR q-value < 0.25; C580R_DHA_treated versus C580R_untreated: NES = 1.2457103, FDR q-value < 0.25). PF3D7_1441800 has been reported to reduce EVs production when knocked out in . Altogether, our findings suggest a role for EVs in developing ART resistance and warrant further studies interrogating this association.
疟疾仍然是撒哈拉以南非洲（SSA）的重要疾病。青蒿素（ART）为基础的联合疗法（ACTs）在疟疾控制方面取得了巨大进展。然而，人们担心抗 ART（ARTr）疟原虫即将传播到 SSA，这威胁到已经取得的成果。为了减轻这种风险，人们已经努力寻找新的药物靶点。因此，需要进行更多的研究来加深我们对生物学的理解。疟原虫外泌体（EVs）在生物学中的作用还不完全清楚。最近，据报道，ART 耐药相关的转录谱涉及几个与囊泡运输、蛋白毒性应激、红细胞重塑和线粒体代谢有关的生物学过程。我们使用未同步化寄生虫培养物的批量 RNA 测序，在未经处理、0.1%二甲亚砜和 700nM 双氢青蒿素处理 6 小时的情况下，研究了 EVs 在产生 ARTr 表型中的作用。由于在疟原虫 EVs 生物发生方面的途径和基因本体分析受到其 curated 知识库的限制，我们使用模块化（基因集）分析方法来探索 EVs 生物发生模块是否与 ARTr 表型相关。我们首先生成了感兴趣的明确 EVs 模块，并使用统计工具来确定它们在寄生虫和处理条件之间的表达差异。然后，我们使用基因集富集分析来确定每个感兴趣的 EVs 模块与 ARTr 表型之间的关联强度。这种转录组模块表型关联研究（TMPAS）是一种从批量基因表达数据中进行有意义发现的强大方法。我们确定了四个感兴趣的 EVs 模块，并报告说，一个代表与 PF3D7_1441800 相关的基因集具有相关性的 EVs 模块 - 与疟原虫中的 EVs 生物发生有关 - 与 ARTr 表型相关（R539T_DHA 处理与 R539T 未处理相比：归一化富集得分（NES）= 1.1830174，FDR q 值 < 0.25；C580R_DHA 处理与 C580R 未处理相比：NES = 1.2457103，FDR q 值 < 0.25）。PF3D7_1441800 已被报道在敲除时会减少 EVs 的产生。总的来说，我们的发现表明 EVs 在产生抗 ART 方面发挥作用，值得进一步研究。
