Induced Alternative Reading Frame (ARF) expression in hs:ARF fish suppresses cardiac regeneration. (a) Representative polymerase chain reaction (PCR) product of ARF expression from three experimental replicates of wild type (WT) and hs:ARF heart RNA on 15 dpi. The product run on gel electrophoresis shows ARF expression present in hs:ARF fish while absent in WT fish. (b) Acid Fuchsin Orange G (AFOG) and troponin staining of WT and hs:ARF heart cryosections on 15 days post-injury (dpi). The dotted lines demarcate the injury site. Red stains are for fibrin. Blue stains are for collagen. Brown stains are for muscle. Green stains are for troponin. (c) Myocardial recovery measured by troponin infiltration into the injury site. Infiltration quantified by imaging software shows decreased troponin in the injury site of hs:ARF fish compared to WT fish. N = 8 hearts. Results are shown as mean ± standard error. The * represents a statistically significant difference.