Tissue-specific gene expression by qPCR in WT and ARF:ARF fish over time. (a) Representative PCR product of ARF expression from three experimental replicates of WT and ARF:ARF heart RNA. The product run on gel electrophoresis shows ARF expression present in ARF:ARF fish while absent in WT fish at 11 dpi. (b) qPCR of fibroblast growth factor 17b (fgf17b), fibroblast growth factor receptor 2c (fgfr2c), vascular endothelial growth factor Aa (vegfaa), and twist1b mRNA expression for WT and ARF:ARF fish at 11 dpi. Results show a significant decrease in the expression of fgf17b, vegfaa, and twist1b in ARF:ARF fish. No significant difference occurred for fgfr2c. N = 8 hearts. (c) fgf17b and twist1b mRNA expression for WT fish over time compared to uninjured WT control. fgf17b and twist1b rise steadily after cryoinjury and peak by 11 dpi before tapering down to the uninjured baseline by 30 dpi. N = 18 hearts. (d) fgf17b, twist1b, and ARF mRNA expression for ARF:ARF fish over time compared to uninjured ARF:ARF control. ARF is significantly elevated above the uninjured baseline from 7–30 dpi. fgf17b is never elevated above the uninjured baseline. twist1b expression is only elevated above the uninjured baseline on 11 dpi. N = 24 hearts. (e) Correlation between interval change in ARF expression with changes in fgf17b and twist1b expression at any time point. ARF expression trended toward inverse correlation with fgf17b expression and was inversely correlated with twist1b expression. N = 24 hearts. Results are shown as mean ± standard error. The * represents a statistically significant difference.