Fig. 4: Dronc, but not the effector caspases or the Dark apoptosome, is required for DARE cell proliferation and tissue regeneration.

a Assessment of apoptosis-related RNAi lines and transgenes used in this study for suppressing Hid-induced apoptosis in Drosophila photoreceptor cells. The indicated transgenes were ectopically expressed in the retina using the GMR-Gal4 driver. Two independently generated Diap1 transgenes were used: Diap1(1) (Fig. 4f) and Diap1(2) (Fig. 7i). Representative eyes of newly eclosed males are shown. b, c, f, h, i Irradiated WIDs expressing the transgenic combination described in Fig. 3a (control; b) or with DARE cell-specific knockdown of dronc (c) or dark (i), or overexpression of Diap1 (f) or P35 (h), were monitored at 4, 24, and 48 hpi. d, k Quantification of total DARE cell fluorescent area shown in (b, c, i) expressed as a percentage of total WID area. e, g, j The graphs depict total size in square micrometers of 48 hpi WIDs shown in (b, c, f, h, i). Statistical tests: Two-tailed unpaired Student’s t-test (b, e, g, k); one-way ANOVA followed by Dunnett’s multiple comparisons test (j). All data points, including outliers, are shown in box plot format. The lower and upper whiskers represent the minimum and maximum values, respectively; the center line denotes the median; and the lower and upper box bounds correspond to the medians of the lower and upper halves of the dataset. Each dot represents a single WID, reflecting the number of biologically independent WID samples (n). Numbers of WIDs examined were: 25 (WT) and 22 (dronc^Ri) in (d, e); 20 (WT) and 25 (Diap1^OE) in (g); 50 (WT), 25 (P35), and 12 (dark^Ri) in (j); and 29 (WT) and 12 (dark^Ri) in (k). **p < 0.01; ***p < 0.001; ****p < 0.0001; ns, not significant. p-value in (d): p = 0.0001 (WT vs. dronc^Ri); (e): p = 0.0022 (WT vs. dronc^Ri); (g): p < 0.0001 (WT vs. Diap1^OE); (j): p = 0.7721 (WT vs. P35) and p = 0.9994 (WT vs. dark^Ri); (k): p = 0.7519 (WT vs. dark^Ri).