Expression and localization of PfSAMS-HA in the P. falciparum blood stages. (A) Expression of PfSAMS-HA in blood-stage parasites. Lysates of asexual blood stages (ABS) of the ring, trophozoite, and schizont stage and of immature (imGC) and mature (mGC) gametocytes of the PfSAMS-HA-KD parasite line were immunoblotted with rat anti-HA antibody to detect PfSAMS-HA (~50 kDa); immunoblotting with antisera directed against Pf39 (39 kDa) was used as loading control. (B) Localization of PfSAMS-HA in the asexual blood stages and gametocytes. Immunofluorescence assays were employed, using rat anti-HA antibody, to detect PfSAMS-HA in trophozoites (TZ), schizonts (SZ), and gametocytes (GC) of stages II–V (green), of the PfSAMS-HA-KD parasite line. Counterlabeling of the asexual blood stages was done using mouse anti-Pf92 antisera and of gametocytes with rabbit anti-Pfs230 antisera (red). The nuclei were labeled with Hoechst 33342 nuclear stain (blue). Bar; 5 µm. (C) Subcellular fractionation of PfSAMS-HA parasites. Nuclear and cytosolic fractions were obtained from schizonts of the PfSAMS-HA-KD parasite line and the fractions were immunoblotted with rat anti-HA antibody. Purity of the nuclear and cytosolic fractions was confirmed by immunoblotting with mouse antiserum directed against the cytosolic protease PfFalcilysin (138 kDa) and rabbit antibody directed against the nuclear histone H3 mark H3K4me3 (15 kDa), respectively. The results (A–C) are each representative of three independent experiments.