PfERC is not required for protein trafficking or organellar biogenesis. In these parasite lines, the endogenous locus of PfERC was tagged with the inducible version of the ribozyme gene, glmS, or with the inactive version of the ribozyme, M9 (termed PfERC-glmS and PfERC-M9, respectively). (A) Representative SIM images of PfERC-glmS and PfERC-M9 schizonts incubated with GlcN for 48 h and stained with anti-MSP1 and the nuclear stain DAPI. From top to bottom, the images are DAPI (blue), anti-MSP1 (green), and fluorescence merge. Bar, 2 mm (C) Representative SIM images of PfERC-glmS and PfERC-M9 schizonts incubated with GlcN for 48 h and stained with anti-RAP1 and the nuclear stain DAPI. From top to bottom, the images represent DAPI (blue), anti-RAP1 (green), and fluorescence merge. Bar, 2 mm. (G) Representative TEM images of synchronized PfERC-glmS and PfERC-M9 schizonts grown for 48 h with GlcN and incubated with C1 for 4 h, as shown in Fig. 3A (n=2 biological replicates). Small arrowheads (white) point to micronemes, while large arrowheads (black) point to rhoptries. Bar, 200 nm.

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