Fig. 5. Expression of recombinant His-tagged CfNek in Crithidia. (A,B) Immunofluorescence microscopy of Crithidia cells transfected with His-CfNek (A) or vector only (B). The cells were fixed with methanol and stained with a His-antibody (red) and with Hoechst blue to visualise DNA. The immunofluorescence images were overlaid with the corresponding phase contrast images to allow easier localisation. Note that only His-CfNek-expressing cells show a staining of the flagellar attachment zone/basal body. Bar, 5 µm. (C) Immunoblot analysis of total cell extracts from His-CfNek-expressing and control cells. Proteins were separated on a 10% polyacrylamide gel, blotted and stained with anti-His antibody. Only the extract from CfNek-expressing cells shows a corresponding band of 56 kDa.