|
Fig. S8
Regenerative responses but not formation of a wound epidermis are blocked in dormant fins a Longitudinal cryosections stained for the epidermal marker p63 and the cell surface marker β- catenin reveal that formation of a multi-layered wound epidermis did occur in hsp70l:dnFgfr1-GFP transgenic fish subjected to the indicated heat-shock regime. However, the basal layer of the epidermis, which is a hallmark of the specialized wound epidermis forming in regenerating fins, is only evident in wild-type fins at 3 d.p.a. (white arrowhead), but did not form in the FGF signaling inhibited fins. b Heat shocks applied 4x daily resulted in robust expression of dnFgfr1-GFP in hsp70l:dnFgfr1-GFP fish in ray and inter-ray tissue by 8 d.p.a. (white arrowheads). After a 5-day recovery period, GFP expression was no longer detected in inter-ray tissue (yellow arrowheads) and fluorescence in rays had dropped to background levels observed in wild-type fish. BF, bright-field image. c Surgical removal of the skin at the distal tip of non-amputated fins did not result in ray growth, even when followed to 2 months post injury (m.p.i.). Dashed line indicates the injury plane. n=17 fish, 67 rays. d Re-amputation of individual rays induced regenerative growth in recessed rays (8 of 8 rays) of dormant hsp70l:Axin1-YFP transgenic fins (black arrowheads), white arrowheads indicate the primary amputation plane. n = 8 fish. Scale bars: a, 100 μm; c,d, 500 μm