Left: ABCI3 foci localize to punctate structures in the parasite cytosol and occasionally with the nucleus, ER, or DV ABCI3 FLAG-tagged parasites were stained with DAPI (40,6-diamidino-2-phenylindole) (nucleus, blue) and antibodies specific to FLAG (green), PfCRT (DV membrane, red), and BiP (ER, magenta). Scale bars, 2 mm. No substantial colocalization was observed with the digestive vacuole (DV) marker PfCRT, the ER marker binding immunoglobulin protein (BiP). Right: IEM image of an HA-tagged ABCI3 trophozoite stained with anti-HA antibodies, revealing staining in the cytosol, nucleus, nuclear membrane, and ER. Arrowheads highlight organelles of interest. C, cytosol; ER, endoplasmic reticulum; N, nucleus; NM, nuclear membrane; Hz, hemozoin crystals. Scale bar, 500 nm. IEM analysis of at least eight parasites cultured independently in triplicate (31 total images) localized ABCI3 49% of the time to the cytosol and 24% to the nucleus and nuclear membrane. Other sites of localization included the DV (8%), the plasma membrane (6%), and the ER and intracellular vesicles (13%).

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