Fig. 3. Acidocalcisome defects in ap3 promastigotes. (A, top panels) Lysotracker labelling of acidic compartments in L. major promastigotes. The two types of signals observed for the ap3 cell line, including the MVT-lysosome-like tubular labelling, are displayed in the four middle panels. (A, bottom panels) Acridine-Orange-labelling of acidic compartments in L. major promastigotes. (B) Measurements of Neutral Red change in absorbance at 540 nm due to acidic environments of L. major promastigotes. Data represent the means ± standard deviations (s.d.) from four independent experiments. (C) Visualisation of polyP-enriched vesicles (yellow) with DAPI in L. major promastigotes. n, nucleus; k, kinetoplast. All scale bars, 10 µm. Corresponding DIC images are shown as well.