Fig. 10: DARE cell clones are resistant to re-irradiation-induced apoptosis.
a Quantification of dying cells in irradiated WIDs, as shown in Fig. 1b, was performed 4 h after either the first (single) or second (double) irradiation, expressed as the percentage of dying cell area relative to the total WID area. b A representative irradiated WID expressing the DDBS/G-TRACE system (as in Fig. 3a), re-irradiated and dissected as in (a), and immunostained with anti-cDcp-1 to mark dying cells (white). DARE cells and their derived clones are shown in red and green, respectively; overlap appears yellow. (b’-b”’) Enlargements of the boxed region in (b) with each panel displaying only two channels at a time to visualize overlap: DARE cells (red) and clones (green) labeled by G-TRACE (b’); DARE cell clones (green) and cDcp-1 (red) (b”); DARE cells (green) and cDcp-1 (red) (b”’). c A paired scatter plot quantifies cDcp-1-positive dying DARE and NARE cells 4 h after the second irradiation, expressed as their percentages within the total dying cell population in a WID. To ensure accuracy, 20 optical Z-slices were analyzed per WID to measure the overlaps. Statistical tests: Two-tailed unpaired Student’s t-test (a). Graphs were generated and presented as in Fig. 1b. Numbers of WIDs examined was 8 (single irradiation) and 12 (double irradiation) in (a). ****p < 0.0001. In (c), all data points, including outliers, are shown as individual values; red indicates the mean (dots) with SD (whiskers). p-value in (a): p < 0.0001 (Single irradiation vs. Double irradiation). d A model of WID regeneration through compensatory proliferation following irradiation. The illustration depicts three adjacent cells: a dying cell, a DARE cell, and a NARE cell. Signaling pathways and components identified in this study are shown within the DARE cell, with arrows indicating activation and T-bars indicating inhibition. Dashed lines represent proposed interactions based on this study and the literature. A detailed explanation of the model is provided in the Discussion. e Illustrations showing the interplay between DARE and NARE cells during (i) normal proliferative homeostasis, (ii) reduced DARE cell proliferation, and (iii) complete absence of DARE cells. Illustrations in (d, e) were created in BioRender. Braun, T. & Yacobi-Sharon, K. (2025) https://BioRender.com/jtk6e8b.
