Fig. 9

Expression of Cx43 in dermal fibroblasts rescues both regenerate length and segment length. A: Regenerate length is significantly increased in fins where Cx43 is induced in dermal fibroblasts, but not in fins where Cx43 is induced in other lineages. B: Segment length is significantly increased in fins where Cx43 is induced in dermal fibroblasts, but not in fins where Cx43 is induced in other lineages. Both regenerate and segment length measurements were taken as the ratio of the GFP-positive clone length over the analogous fin ray on the opposite side of the fin. Statistically significant differences were determined by the Student's t-test, where P?<?0.001 (***). Error bars represent the standard deviation. C: Representative image of a fin containing a GFP-positive clone in the dermal fibroblasts. The amputation plane is indicated by a dotted line. Scale bar?=?150?µm. Insets show higher magnification views of a region of both the GFP-positive fin ray and in the contralateral GFP-negative fin ray (bright-field is shown to better visualize the joints). Joints are indicated as arrowheads in both the GFP-positive fin ray and in the GFP-negative fin ray. D: Higher magnification view of the GFP-positive clone to show GFP expression in dermal fibroblasts. Dermal fibroblast clones are notable for the ability to see the unlabeled artery running down the middle of ray (arrow pointing to middle of ray), whereas osteoblast clones obscure the artery. Dermal fibroblast clones also show distinct GFP-positive fibroblast cells that are adjacent to, but not contained within, the ray itself (arrows pointing to GFP-positive cells flanking the ray), whereas osteoblast clones remain strictly associated with the hemirays.