Sinha Ameya, Lee Benjamin Sian Teck, Kwah Junmei Samantha, Liang Jiaqi, Murray Hannah, Omelianczyk Radoslaw Igor, Baumgarten Sebastian, Dedon Peter C, Preiser Peter R
School of Biological Sciences, Nanyang Technological University, Singapore; Department of Biological Engineering.
Antimicrobial Resistance IRG, Singapore-MIT Alliance for Research and Technology, Singapore.
bioRxiv. 2025 Aug 28:2025.08.28.672746. doi: 10.1101/2025.08.28.672746.
Artemisinin has long been a first-line antimalarial. Yet, its mode of action is still poorly understood. Emergence of artemisinin-resistant strains highlight the importance of addressing this question so as to develop better drugs and overcome resistance. In this study, we performed RNA-sequencing and proteomics studies on artemisinin treated parasites indicated a striking difference in the codon-usage pattern of differentially translated genes. Using a liquid chromatography-coupled mass spectrometry (LC-MS)-based platform, we have quantified the full spectrum of modified ribonucleosides on tRNA in in response to the drug. We found that N-threonyl-carbomyladenosine (tA), a universal tRNA modification found at position 37 is hypomodified in response to artemisinin induced stress. Additionally, we also found that artemisinin treatment resulted in a downregulation of PfSua5, an enzyme involved in the tA biosynthesis machinery. These findings provide new insights into how artemisinin works. More broadly, the findings exposes the tRNA epitranscriptome as a vulnerability in the parasite that can be exploited for new drugs.
青蒿素长期以来一直是一线抗疟药物。然而，其作用模式仍未得到充分理解。青蒿素耐药菌株的出现凸显了解决这一问题的重要性，以便开发出更好的药物并克服耐药性。在本研究中，我们对经青蒿素处理的疟原虫进行了RNA测序和蛋白质组学研究，结果表明差异翻译基因的密码子使用模式存在显著差异。使用基于液相色谱-质谱联用（LC-MS）的平台，我们定量分析了药物处理后tRNA上修饰核糖核苷的全谱。我们发现，在37位发现的一种普遍存在的tRNA修饰——N-苏氨甲酰腺苷（tA），在青蒿素诱导的应激反应中修饰不足。此外，我们还发现青蒿素处理导致参与tA生物合成机制的PfSua5酶表达下调。这些发现为青蒿素的作用方式提供了新的见解。更广泛地说，这些发现揭示了tRNA表观转录组是疟原虫中的一个脆弱点，可用于开发新药。
