Fig. S3

Notum 1a is not part of a feedback loop regulating Fgf signaling. (A-N) Overexpression of notum1a in Tg(hs:notum1a) embryos does not alter FGF signaling. (A-C) Expression of pea3 at 22 hpf in non-transgenic embryos heat shocked at 20 hpf in the whole embryo (A), tail (B) and MHB (C). (D-F) Expression of pea3 at 22 hpf in transgenic embryos heat shocked at 20 hpf is not altered. egfp co-staining in the heart indicates the presence of the transgene (arrowhead). (G-I) Expression of spry4 at 22 hpf in non-transgenic embryos heat shocked at 20 hpf in the whole embryo (G), tail (H) and MHB (I). (J-L) Expression of spry4 at 22 hpf in transgenic embryos heat shocked at 20 hpf is not altered. egfp expression is present in J and L (arrowheads). (M) Expression of spry4 at 24 hpf in non-transgenic embryos heat-shocked at 22 hpf. (N-Q) Expression of notum1a at 24 hpf in non-transgenic embryos heat-shocked at 22 hpf. (O) A dorsal view of the head reveals notum1a expression in the eye (arrow) and the anterior extent of notum1a expression in the hindbrain in rhombomere 3. (P) A lateral view of the head shows MHB extending through the entire dorsoventral axis of the brain (asterisk). (Q) In the tail, notum1a expression diminishes posteriorly (red arrow). (R) At 24 hpf, spry4 expression is absent in heat-shocked Tg(hsp70l:dn-fgfr1-EGFP)^pd1/+embryos 2 hours post-heat-shock. (S-V) Expression of notum1a at at 24 hpf in n Tg(hsp70l:dn-fgfr1-EGFP)^pd1/+embryos heat-shocked at 22 hpf. Although the majority of notum1a expression is intact following heat-shock (S), anterior eye expression is lost (arrow, T) and expression is expanded into the rhombic lip (arrowhead, T, U). The dorsoventral extent of MHB expression is reduced (asterisk, U). The posterior domain in the tail is expanded (V, red arrow).