Evolution of Fitness Cost-Neutral Mutant PfCRT Conferring P. falciparum 4-Aminoquinoline Drug Resistance Is Accompanied by Altered Parasite Metabolism and Digestive Vacuole Physiology

• DOI: 10.1371/journal.ppat.1005976
• Publication Date: 2016-11-10T18:47:17Z
• Authors: Stanislaw J. Gabr...; Satish K. Dhingra; Jill M. Combrinck; Ian A. Lewis; Paul S. Callaghan; Matthew R. Hassett; Amila Siriwardana; Philipp P. Henrich; Andrew H. Lee; Nina F. Gnädig; Lise Musset; Manuel Llinás; Timothy J. Egan; Paul D. Roepe; David A. Fidock
• Keywords: 570; Genotype; QH301-705.5; Drugs--Metabolism; Plasmodium falciparum; Immunology; Drug Resistance; Protozoan Proteins; Microbial Sensitivity Tests; Mass Spectrometry; Antimalarials; 03 medical and health sciences; [SDV.MHEP.MI]Life Sciences [q-bio]/Human health and pathology/Infectious diseases; Drug resistance in microorganisms; [SDV.BBM.GTP]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Genomics [q-bio.GN]; Pathology; Humans; [SDV.MP.PAR]Life Sciences [q-bio]/Microbiology and Parasitology/Parasitology; Biology (General); Malaria, Falciparum; 0303 health sciences; FOS: Clinical medicine; Membrane Transport Proteins; [SDV.BBM.BM]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Molecular biology; Chloroquine; RC581-607; 3. Good health; Mutation; Vacuoles; Aminoquinolines; [SDV.SPEE]Life Sciences [q-bio]/Santé publique et épidémiologie; Genetic Fitness; Immunologic diseases. Allergy; Research Article

Southeast Asia is an epicenter of multidrug-resistant Plasmodium falciparum strains. Selective pressures on the subcontinent have recurrently produced several allelic variants parasite drug resistance genes, including P. chloroquine transporter (pfcrt). Despite significant reductions in deployment 4-aminoquinoline (CQ), which selected for mutant pfcrt alleles that halted CQ efficacy decades ago, locus continuously evolving. This highlighted by presence a highly mutated allele, Cam734 pfcrt, has acquired singular ability to confer without associated fitness cost. Here, we used pfcrt-specific zinc-finger nucleases genetically dissect this allele pathogenic setting asexual blood-stage infection. Comparative analysis and growth profiles recombinant parasites express or thereof, Dd2 (the most common Asian variant), wild-type revealed previously unknown roles PfCRT mutations modulating susceptibility multiple antimalarial agents. These results were generated GC03 strain, earlier studies, might differ natural isolates harboring allele. Results presented herein show Cam734-mediated dependent rare A144F mutation not been observed beyond Asia, reveal distinct impacts other Cam734-specific rates. Biochemical assays broad impact isoforms metabolism, nucleoside triphosphate levels, hemoglobin catabolism disposition heme, as well digestive vacuole volume pH. from our study provide new insights into complex molecular basis physiological PfCRT-mediated resistance, inform ongoing efforts characterize novel can undermine first-line regimens.