Figure 5

Figure 5

Conditional overexpression of cmyc in ∆113p53⁺ cells promotes zebrafish CM proliferation and heart regeneration. (A) Immunostaining of MF20 (in red) and EDU incorporation assay (in green) of WT and Tg(∆113p53:cmyc) injury hearts at 14 dpa. Framed areas were magnified in right panels. Scale bar: 50 μm or 20 μm as indicated. (B) Statistical analyses of EDU⁺ CMs in A. The EDU⁺ CMs were presented as the percentage of the total MF20⁺ cells at the injury sites. Each dot represents an individual heart (round dot, WT group; frame dot, Tg(∆113p53:cmyc) group). n: 10–11 hearts/sample. The experiment was repeated three times. (C) Fibrin clot stained with Masson’s trichrome on the cryosections of WT and Tg(∆113p53:cmyc) injury hearts at 14 and 30 dpa. Yellow dotted lines indicate the approximate injury area. Scale bar: 200 μm. (D) Statistical analyses of scar areas in (C). Average injury area with fibrin clots on heart sections was presented as the percentage of the total ventricular area. Each dot represents an individual heart (round dot, WT at 14 dpa group; frame dot, Tg(∆113p53:cmyc) at 14 dpa group; positive triangle dot, WT at 30 dpa group; inverted triangle dot, Tg(∆113p53:cmyc) at 30 dpa group). n: 10–12 hearts/sample. Statistical analysis was performed by Student’s two-tailed unpaired t test in GraphPad Prism 8. The p values were represented by n.s. and asterisks. *, p < 0.05; ***, p < 0.001.