Fig. 4
Wnt/β-Catenin Signaling in the Proximal Medial Blastema Is Required for Bone Formation
(A) axin1 overexpression in the medial proximal blastema does not significantly reduce H3P+ blastemal cells in her4.3:TetA AmCyan; TetRE:Axin1-YFP double transgenic fish. In contrast, proliferation is strongly reduced when axin1 is directed to both the distal and medial proximal blastema using the ubiquitin promoter.
(B) axin1 overexpression in the medial proximal blastema but not in committed osteoblasts reduces the fraction of the regenerate stained with the bone calcification marker Alizarin Red. Bracket indicates the noncalcified distal region of the regenerate.
(C) axin1 overexpression in the proximal blastema reduces expression of the osteoblast commitment marker sp7.
In (A)-(C), arrowheads, amputation plane. Scale bar, 200 μm. Error bars indicate error of the mean.