Fig. 3: EB-derived Actβ supports regenerative growth and tissue repair.

a, b Quantification of PH3+ cells in midguts dissected from Ecc15 infected control flies and flies with ISC/EB-specific RNAi- (a; n = 22, 15, 15, 15) or CRISPR/Cas9-mediated (b; n = 20, 18) babo knockdown. c Mated flies with ISC/EB-specific knockdown of babo display reduced survival to oral Pe infection (n = 98, 93). d, e Quantification of PH3+ cells in midguts dissected from control flies and flies expressing babo-ARNAi, babo-BRNAi or babo-CRNAi in ISCs/EBs 16 h post Ecc15 (d; n = 18, 20, 19, 20, 19, 20, 20) or Pe (babo-ARNAi; e; n = 15, 16, 17) infection. f–h′ Representative confocal images of dissected posterior midguts from control flies (f, f″) and flies expressing babo-ARNAi (g, g″) in ISCs/EBs 16 hours post Ecc15 infection, and quantification of cell populations (h, h′n = 14, 13). i RT-qPCR analysis on dissected midguts 6- and 16 hours post Pe infection (n = 5, 5, 5). j–m″ Representative confocal images of dissected posterior midguts harboring actb-Gal4>UAS-GFP and Su(H)-lacZ (labeling EBs) stained for GFP (Green), lacZ (red), Pros and Dl (white), and DNA (blue) 16 hours post Ecc15 (k, k″) or Pe (l, l″) infection, and quantification of EECs, ISCs, and EBs positive for GFP signal (m, m″; n = 7, 10, 12). n–q Quantification of PH3+ cells in midguts dissected from control flies and flies expressing actβRNAi in EBs (n; pool of two experiments, n = 23, 45, 45) or actβRNAi (o, q; n = 22, 21, 22 and n = 20, 19, 20) or Cas9 + actβgRNA (p; n = 20, 19) in ISC+EBs (esgts) 16 hours post Ecc15 (n–p) or Pe (q) infection. r–u′ Representative confocal images of dissected posterior midguts from control flies (r) and flies expressing babo-ARNAi (s) and babo-CRNAi (t) in ISCs/EBs 48 hours (16H on Ecc15 + 32H recovery on normal food) post Ecc15 infection and quantification of cell turnover using esgReDDM tracing for 10 days (u, u′; n = 21, 25, 19). Significance was tested with two-tailed unpaired t-tests (b, h, h′,p), one-way ANOVA (a, d, e, i, n, u′) or Kruskal Wallis (m, m′, m″, o, q, u) with post-hoc multiple comparison analysis and a Mantel-cox Log-rank test (c). Data are presented as mean values ±SD. Source data are provided as a Source Data file.