Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, New York, USA.
Center for Malaria Therapeutics and Antimicrobial Resistance, Columbia University Irving Medical Center, New York, New York, USA.
mBio. 2024 Jan 16;15(1):e0183223. doi: 10.1128/mbio.01832-23. Epub 2023 Dec 7.
Our study leverages gene editing techniques in asexual blood stage parasites to profile novel mutations in mutant PfCRT, an important mediator of piperaquine resistance, which developed in Southeast Asian field isolates or in parasites cultured for long periods of time. We provide evidence that increased parasite fitness of these lines is the primary driver for the emergence of these PfCRT variants. These mutations differentially impact parasite susceptibility to piperaquine and chloroquine, highlighting the multifaceted effects of single point mutations in this transporter. Molecular features of drug resistance and parasite physiology were examined in depth using proteoliposome-based drug uptake studies and peptidomics, respectively. Energy minimization calculations, showing how these novel mutations might impact the PfCRT structure, suggested a small but significant effect on drug interactions. This study reveals the subtle interplay between antimalarial resistance, parasite fitness, PfCRT structure, and intracellular peptide availability in PfCRT-mediated parasite responses to changing drug selective pressures.
我们的研究利用无性血阶段寄生虫中的基因编辑技术，对在东南亚田间分离株或长期培养的寄生虫中出现的新型 PfCRT 突变体进行分析。PfCRT 是哌喹耐药的重要介体，我们提供的证据表明，这些系的寄生虫适应性增加是这些 PfCRT 变异体出现的主要驱动因素。这些突变体对哌喹和氯喹的寄生虫敏感性产生了不同的影响，突出了该转运蛋白中单点突变的多方面影响。使用基于脂质体的药物摄取研究和肽组学分别深入研究了耐药的分子特征和寄生虫生理学。能量最小化计算表明，这些新突变可能对 PfCRT 结构产生微小但显著的影响，表明对药物相互作用有影响。这项研究揭示了抗疟耐药性、寄生虫适应性、PfCRT 结构以及 PfCRT 介导的寄生虫对不断变化的药物选择压力的反应中细胞内肽可用性之间的微妙相互作用。
