Quinine localizes to a non-acidic compartment within the food vacuole of the malaria parasite Plasmodium falciparum

• Published in: Malaria Journal
• Main Authors: Bohórquez Elaine B, Chua Michael, Meshnick Steven R
• Format: Article in Journal/Newspaper
• Language: English
• Published: BMC 2012
• Subjects: Quinine; Plasmodium falciparum; Pfmdr1; Copy number; Arctic medicine. Tropical medicine; RC955-962; Infectious and parasitic diseases; RC109-216; Arctic
• Online Access: https://doi.org/10.1186/1475-2875-11-350; https://doaj.org/article/d96bf4b6a2464894b49086400703cacb

Abstract Background The naturally fluorescent compound quinine has long been used to treat malaria infections. Although some evidence suggests that quinine acts in the parasite food vacuole, the mechanism of action of quinine has not yet been resolved. The Plasmodium falciparum multidrug resistance ( pfmdr1 ) gene encodes a food vacuolar membrane transporter and has been linked with parasite resistance to quinine. The effect of multiple pfmdr1 copies on the subcellular localization of quinine was explored. Methods Fluorescence microscopy was used to evaluate the subcellular localization of quinine in parasites containing different pfmdr1 copy numbers to determine if copy number of the gene affects drug localization. The acidotropic dye LysoTracker Red was used to label the parasite food vacuole. Time-lapse images were taken to determine quinine localization over time following quinine exposure. Results Regardless of pfmdr1 copy number, quinine overlapped with haemozoin but did not colocalize with LysoTracker Red, which labeled the acidic parasite food vacuole. Conclusions Quinine localizes to a non-acidic compartment within the food vacuole possibly haemozoin. Pfmdr1 copy number does not affect quinine subcellular localization.