Fig. 1

Fig. 1

Calcineurin inhibition is sufficient to override genetic encoding of size. (A) Regenerative growth of zebrafish pectoral fins after resection to ~50% of pre-cut fin length at 0 days post amputation in different genetic backgrounds with short- (cx43^sof/sof) or long- (kcnk5b^alf) fin size relative to wild-type fish. Dashed lines indicate pre-cut pectoral fin length. Data normalized to standard length (STL) of each fish. ANOVA genotype by treatment interaction test F(2,23) = 27.89, p < 0.0001. Pairwise comparisons (ANOVA p-value): alf FK506-alf DMSO (1.0), alf DMSO-sof FK506 (0.25), alf DMSO-wt FK506 (0.25), wt FK506-sof FK506 (1.0), sof FK506-sof DMSO (<0.0001), wt FK506-wt DMSO (0.0013). (B) Representative ventral view of pectoral fins after regeneration. Black line indicates unoperated pectoral fin length. Red line indicates pectoral fin length after treatment with FK506 during regeneration. Black dashed line highlights site of amputation. Growth rate of FK506-treated regenerating caudal fins. (D) Caudal fins were resected to 50% of their original size and treated with FK506. Growth rate is analyzed through 9 days post amputation, when regenerative growth rate for DMSO treated fins begins to slow. Two-tailed t-test p < 0.0007 for suppression of growth in the absence of kcnk5b. Error bars represent ± SEM.