Fig 4. TgFBXO1 apical structures form after centrosome duplication and are localized apically to the parasite centrosome.

(A). TgFBXO1^HA-expressing parasites were fixed and stained to detect TgCentrin1, TgFBXO1, and DNA during S, early M (EM), and late M (LM) phases. Arrowheads highlight TgFBXO1 apical structures and arrows highlight TgCentrin1. Bars = 2μm. A schematic depicting the cell cycle phases is shown. (B). Parasites were treated with 3 μM SB505124 (or DMSO as a vehicle control) for 24 h, fixed and then stained to detect TgCentrin1, TgFBXO1, and DNA. Note the appearance of SB505124-treated parasites with >2 centrin1⁺ foci and disorganized TgFBXO1 staining. Bars = 5 μm. (C). Quantification of numbers of parasites with apical TgFBXO1 structures. Data represents averages and standard deviations of three independent experiments with at least 50 parasites examined/experiment (D). TgFBXO1^HA parasites were stained to detect TgFBXO1 and the kinetochore marker TgNuf2. Note TgFBXO1^HA apical structures form after kinetochore duplication but before separation is completed as evidenced by the lobed TgNuf2 staining (Insert). Bars: 2μm.