Figure 3 : Spatio-temporal control of cell death during regeneration and wounding (a–c) TUNEL staining during the time course of regeneration.

From: Sustained production of ROS triggers compensatory proliferation and is required for regeneration to proceed

Figure 3

For each time point, a higher magnification is shown for the distal (segment 1 and 2, blue frame) and proximal (segment 3–4, red frame) regions of the fin. Numerous TUNEL-positive cells were detected in the proximal region of the fin (segments 3–6) at 18 hpa (arrowheads). (b) Quantification of cell death. For each fin, TUNEL-positive cells (gray) or active Caspase-3 positive cells (black) were counted in ray and inter-ray 2 in all segments. The uncut control (nc) corresponds to positive cells below the level of amputation in amputated fins (first bifurcation level) and was taken as 1. (c) Longitudinal cross-sections obtained at 18 hpa revealed numerous positive cells in the stump epidermis (arrows) and only a few cells in the mesenchyme (arrowhead). (d, e) Time course of cell death during wounding. TUNEL staining was performed over the indicated time period. The error bars represent the SEM (* p<0.05, **p< 0.01, ***p < 0.001).