Fig. 6. Loss of MMP after Bax translocation to foci in EGF-treated cells. A431/ErbB2/Bax cells were incubated in the presence of EGF or vehicle for 16 hours. Next, the cells were incubated for 30 minutes with MitoTracker CMTMRos (100 nM) and examined by fluorescence confocal microscopy. The mitochondrial network visualized by MitoTracker CMTMRos (red) is present in all control cells, which express Bax*GFP, and is evenly distributed in the cytosol (A). In contrast, cells incubated with EGF show a redistribution of Bax to foci (B, arrow; C, arrowheads), which coincides with a loss of MMP. A few cells, where a translocation of Bax can be observed in one part of the cell, still retain MMP in another region of the same cell that does not show Bax relocation (C, arrow). Bars, 20 µm.