Immunostaining of heart sections for PCNA and MEF2 in 5 dpci animals (Tg(hsp70l:LOXP-STOP-LOXP-pdha1aSTA-T2A-mCherry) and Tg(hsp70l:LOXP-STOP-LOXP-pdk3b-T2A-mCherry) alone (control) or in combination with Tg(myl7:Cre-ERT2), all after tamoxifen and heat shock treatments); magnified view of area in white boxes shown below; arrowheads point to PCNA+ CMs; white dashed lines mark the wound border; percentage of PCNA+ CMs in the border zone shown on the right (n = 4-5 ventricles of each genotype). 