Figure 4

Confocal assisted cell destruction of HeLa cells. (a-f) Confocal images of HeLa cells transfected with pCIG nuclear GFP-expressing vector prior to (a,d), and just after (b,e) cell destruction, and after 3.5 hours of time-lapse analysis (c,f). Before UV irradiation, the S-FLICA apoptosis marker was added to the medium, becoming red in the presence of active caspases. (d-f) Merged images of GFP (green)/S-FLICA (red) colabeling with Nomarski images. Black asterisks indicate the two GFP-positive and the GFP-negative cells that have been targeted for ablation. Note that after 5 seconds of UV irradiation within the nucleus, weak GFP bleaching occurs in targeted GFP-positive cells (white arrows in (b)). After 3.5 hours, all the targeted cells (but not non-targeted cells) express active caspases, as indicated by red labeling. See also Additional file 7.