Role of N-Terminal His6-Tags in Binding and Efficient Translocation of Polypeptides into Cells Using Anthrax Protective Antigen (PA)
Figure 4
Immunofluorescence studies of HUVECs treated with EDIN and His6-EDIN and PA63.
A: HUVECs were intoxicated for 24 h with a combination of PA63 3 µg/ml, His6-EDIN 10 µg/ml and LF1–254-EDIN (LFN-EDIN) 1 µg/ml, as indicated. Cells were fixed and actin cytoskeleton was labelled using FITC-conjugated phalloidin. Bar = 10 µm. Arrows indicate transendothelial cell macroaperture tunnels (TEMs, transcellular tunnels). B: Graph shows percentage of cells with toxin-induced transendothelial cell macroaperture tunnels (TEMs, transcellular tunnels). HUVECs were intoxicated for 24 h with a combination of PA63 3 µg/ml, His6-EDIN or EDIN 10 µg/ml and LF1–254-EDIN (LFN-EDIN) 1 µg/ml, as indicated on the graph legend. Data correspond to means ± SEM (n = 3, 400 cells per condition).