Fig. S5
Wnt/β-catenin signaling receives little reciprocal input from other developmental signaling pathways during fin regeneration, related to figure 5.
(A) sost and wnt10a expression is strongly reduced upon axin1 overexpression for 6 hours in hs:Axin1 transgenic regenerates.
(B) bmp4 (blue) and mCherry (brown) transcripts co-localize in the distal-most blastema (white arrowhead) in 7xTCF:mCherry transgenic regenerates. Note that samples were stained for mCherry 13 expression only shortly, so that only the strongest expression domain in the distal blastema was detected.
(C) actβB (blue) and mCherry (brown) transcripts co-localize in the distal most blastema in 7xTCF:mCherry transgenic regenerates (arrowhead). Note that samples were stained for mCherry expression only shortly, so that only the strongest expression domain in the distal blastema was detected.
(D-H) 7xTCF:mCherry reporter expression is robustly detectable in severely reduced regenerates obtained after prolonged inhibition of Igf (D), Fgf (E), Notch (F), Activin (G) or RA (H) signaling for 48 hours or 72 hours using pharmacological compounds or heat shock-induced overexpression of pathway inhibitors. Pharmacological compounds: cyclopamine, Smoothened antagonist – inhibitor of Hh signaling; IWR-1, Axin stabilizer – Inhibitor of Wnt/β-catenin signaling; LY411575, γSecretase inhibitor – inhibitor of Notch signaling; NVP-AEW541, Igf1 receptor inhibitor – inhibitor of Igf signaling; SB431542, Activin receptor-like kinase receptor 4 (Alk4) inhibitor – inhibitor of Activin signaling. Transgenic lines: cyp26a1, RA degrading enzyme – inhibitor of RA signaling; dnfgfr1, dominant negative Fgf receptor 1 – inhibitor of Fgf signaling; nog3, noggin3 (secreted Bmp antagonist) – inhibitor of Bmp signaling.
(I-O) axin2 expression is robustly detectable after inhibition of Activin (I), Igf (J), Hh (K), Notch (L), Fgf (M), RA (N) or Bmp (O) signaling for 6 hours using pharmacological compounds or heat shock-induced overexpression of pathway inhibitors.
(P) axin2 expression is strongly reduced after inhibition of Wnt/&beta-catenin signaling for 6 hours using the pharmacological compound IWR-1 which stabilizes Axin.
(A-P) Small arrowheads: amputation plane. Scale bars: whole mounts, 200 μm and 100 μm (C); sections, 100 μm.