Left: IFA images of GFP-Kelch13C580Y and GFP-Kelch13wt cell lines expressing EXP1-Tyhigh. a-GFP, endogenous Kelch13; a-Ty1, episomal EXP1-Ty1. Scale bars, 5 mm. Since the NPCA is critical for amino acid acquisition, EXP1 levels might compensate the reduced amino acid supply in ARTR parasites by increasing amino acid access via the NPCs. To test this, we overexpressed EXP1 (by an additional episomal copy of exp1) in the 3D7 Kelch13C580Y parasites, which reduced the growth defect under limiting amino acid levels. Right: IFA images of GFP-Kelch13C580Y (K13C580Y) and GFP-Kelch13wt (K13wt) parasites with an HA-tagged EXP1. a-GFP, Kelch13; a-HA, EXP1-HA. Scale bars, 5 mm. Mesén-Ramírez P, Bergmann B, Elhabiri M, Zhu L, von Thien H, Castro-Peña C, Gilberger TW, Davioud-Charvet E, Bozdech Z, Bachmann A, Spielmann T. The parasitophorous vacuole nutrient channel is critical for drug access in malaria parasites and modulates the artemisinin resistance fitness cost. Cell Host Microbe. 2021 29(12):1774-1787.