Figure 1

Episomal expression of GFP-tagged Pfnek-4 protein in gametocytes and a subset of asexual stage parasites. Live images of Hoechst-stained stage II (A-B), stage III gametocytes (C), and multinucleated-schizont stage (D), from transgenic 3D7 parasites expressing GFP-tagged Pfnek-4 controlled by cognate (Pfnek-4) promoter. Overlay between the green and blue channels, and corresponding DIC images are shown as well. Scale bars, 2.0 μm. E, Immunoblots showing ~62-kDa protein band (arrow) recognized by mouse anti-GFP mAbs (Roche) using parasite extracts (10 μg) from wild type (Wt) 3D7 and Pfnek-4-GFP transgenic (Tg) stage II-V gametocytes and synchronized schizonts of 3D7 and the non-gametocyte-producer F12 clones at day 4 of induction of gametocytogenesis, and from Pfnek-4-GFP transgenic 3D7 synchronized schizonts before (−) and after (+) 30 min-incubation with λ-protein phosphatase. High MW Pfnek-4-GFP species susceptible to λ-protein phosphatase treatment are marked with an asterisk. Note the much lower expression level in asexual parasite extracts as compared to gametocyte extract.