The Malarial Host-Targeting Signal Is Conserved in the Irish Potato Famine Pathogen
Figure 5
Requirement of Sequences Downstream of HT Motif in Protein Export to Erythrocyte Cytosol
(i) Images of live cells exporting a secretory GFP chimera containing the five amino acid HT core (blue) followed by 16 amino acids downstream sequence from PfHRPII (red).
(ii) Removal of the terminal nine amino acids (VHHAHHADV) blocked export to the erythrocyte.
(iii) Replacement of VHHAHHADV with VGMMSMMDV restored export of GFP to the erythrocyte. For quantitative analyses, two hundred fluorescent images were analyzed as described in Materials and Methods.
(iv) Fraction of GFP exported to the erythrocyte cytosol is indicated, and all parasitized cells export the transgene (as expected for stable transfections; unpublished data).
Standard deviations are as shown. Constructs contain SS (black), upstream region (purple), followed by sequence containing core host-targeting motif (blue), the downstream spacer region (red), and GFP (green).
In all cases: p, parasite; e, erythrocyte; nucleus is Hoechst-stained (blue); scale bar is 2 μm.