Fig. 5

Effects of exogenous Xl-kcna5 overexpression on segment length requires Cx43 function. A) Overview of experimental design. At day 0, fins from non-transgenic and transgenic siblings were amputated at the 50 % level and were systemically heat shocked at 37 °C for 1 h at 3 dpa. At 7 dpa/4 dpt, fins were stained with calcein prior to measurements of regenerate length and segment length. B) Fins were measured from amputation plane to distal tip of regenerate (white arrows) on the third-most dorsal fin ray at 7 dpa/4 dpt. C) Segment length was measured as the distance between the first and second joints distal of the amputation plane on the third-most dorsal fin ray (white arrows). Amputation planes are denoted by the white dotted line. D) Quantification of regenerate length shows no difference following heat shock (unpaired t-test, p-value = 0.96). E) Quantification of segment length shows a modest but significant increase in segment length following heat shock (unpaired t-test, p-value <0.01). Because the segment length phenotype does not mimic WT Tg + HS+, the impacts of kcna5 overexpression must be attenuated by less Cx43-GJIC (data from Fig. 2 is shown in gray for direct comparison). Graphs show measurements, mean, and standard deviation. Three independent trials were conducted. dpa, days post-amputation; dpt, days post-treatment.