Fig. S1

Fig. S1 Purmorphamine is a Small Molecule Agonist of Hedgehog Signalling in Zebrafish Embryos

a-c) Phenotype of 26hpf control embryos treated from before midblastula transition (MBT) with 2μl DMSO.

d-f) Phenotype of 26hpf embryos treated prior to MBT with 20μM purmorphamine displaying an altered somitic chevron angle (black arrowheads) and neural defects characteristic of hedgehog activation (blue arrowheads). Pooling of primitive blood is also evident (red arrowhead and asterisk), arising from absence of circulation due to loss of the axial vein (data not shown).

g) Anterior view of 24hpf embryo treated with 2μl DMSO from before MBT (n=20/20) illustrating normal expression of ptc1 (green arrowheads).

h) Anterior view of 5s control embryo treated with 2μl DMSO prior to MBT (n=19/20) illustrating normal expression of pax2.1 (green arrowhead) within the forebrain.

i) 26hpf embryo treated with 2μl DMSO from before MBT (n=20/20) illustrating normal expression of pax6a within the forebrain (green arrowhead).

j) Anterior view of 24hpf embryo treated with 20μM purmorphamine from before MBT (n=17/20) illustrating increased ptc1 expression (green arrowheads).

k) Anterior view of 5s embryo treated with 20μM purmorphamine from before MBT (n=14/20) illustrating increased pax2.1 expression within the forebrain (green arrowhead)

l) 26hpf embryo treated with 20μM purmorphamine from before MBT (n=16/20) illustrating a reduced area of expression of pax6a within the forebrain (green arrowhead).