Fig. 3.

Kcnh2a actively prolongs the fin outgrowth period in lof^t2. (A) Plots comparing the growth (A) and growth rate (B) of regenerating lof^t2/+ (blue) and clutchmate lof^+/+ (red) caudal fins. Curves show actual data fit to (A) a logistic equation reflecting establishment and then progressively slowing outgrowth phases, and (B) an exponential decay equation using time points after the peak growth rate is reached. All data points (≥12 fish per time) are shown in A and mean values are used in B. (C-E) Stitched DIC images showing clutchmate lof^+/+ astemizole-treated (C; 500 nM), DMSO-treated lof^t2/+ (D) and lof^t2/+, astemizole-treated (E; 500 nM) fish at 30 days post-caudal fin amputation (dpa). The dashed yellow line indicates the amputation plane. Scale bars: 1 mm. (F) Quantification of normalized caudal fin regenerative outgrowth from control and astemizole-treated animals. Data points represent individual lof^+/+ (blue circles) and lof^t2/+ (red squares) animals prior to treatment (7 dpa) and post-treatment (30 dpa) with DMSO or astemizole (500 nM). Graph shows mean lengths of the third ventral regenerated ray normalized to DMSO-treated controls at 30 dpa. Each point is an individual animal. ****P<0.0001 for DMSO treated from 7-30 dpa compared with wild-type and lof^t2/+ fin lengths; no significant differences between genotypes at 7 dpa or when comparing 7-30 dpa astemizole-treated wild-type and lof^t2/+ regenerative outgrowth. Statistical tests used one-way ANOVA with Tukey's multiple comparisons tests.