Stage-specific localization of apicoplast-targeted GFP and the effects of brefeldin A (bfa). Distribution of green fluorescence and PfBiP (red) in a early-ring (A, i–iii) and a trophozoite (B, i–iii; a late, ~33 h, trophozoite with two

nuclei stained in blue is shown). Distribution of green fluorescence and indicated secretory marker (red) in: rings incubated with Bfa for 24 h (C, i–iii); rings incubated with Bfa for 24 h, washed, and grown for 18 h in absence of drug (D, i–iii; E, i–iii); and trophozoites incubated with or without Bfa (F, i–iii). Blue indicates DNA stained with Hoechst 33342. White arrows in B, ii, D, ii, and E, ii, indicate apicoplast DNA. Scale bars as indicated in microns. PTS-GFP in rings did not show significant overlap with the resident ER marker PfBiP. Nonetheless, its tubular distribution suggested that it resided in one or more membranous compartments. rings were allowed to mature in the presence of Bfa for 24 h (C, i–iii), the distribution of PTS-GFP as well as PfBiP (C, ii) were altered compared with either control rings or trophozoites shown in A and B. In the presence of Bfa, PfBiP lost its reticular staining and PTS-GFP accumulated in diffuse globular regions that show significant overlap with regions of PfBiP stain: however, PTS-GFP and BiP failed to show the identical distribution in Fig. 3C. The Golgi marker PfERD2 was also reorganized by Bfa treatment, consistent with the action of the drug on blocking transport through the Golgi (C, iii).

Cheresh P, Harrison T, Fujioka H, Haldar K. Targeting the malarial plastid via the parasitophorous vacuole. J Biol Chem. 2002 277(18):16265-77.