Fig. 1

Pharmacological inhibition of signalling pathways on stage 13 explant cultures. a. Wholemount dorsal view of explant cultures treated with, from left to right, DMSO, dorsomorphin, SU5402, IWP-2 and SU5402 + IWP-2 and immunostained for NFM and ISL1/2. Filled arrowheads show the position of the dorsal midline. Empty arrowheads show the position of the trigeminal placode. R, rostral. C, caudal. Scale bars, 50 μm. Insets, Wholemount dorsal view of explant cultures treated with DMSO or dorsomorphin and immunostained for phospho-SMAD1/5/8 and ISL1/2. Scale bars, 50 μm. b. Bar graphs showing ISL1/2+ cell counting on stage 13 explants. Values are mean ± S.E.M. normalised to the mean control value of each experiment. *, significant p values for SU5402 and IWP-2 treatments after multiple comparison using Kruskal-Wallis test with Dunn’s correction and for the SU5402 + IWP-2 for pairwise comparison using two-tailed Mann Whitney test. Dorsomorphin: DMSO (n = 39), 5 μM (n = 19), 10 μM (n = 13). SU5402: DMSO (n = 33), 34 μM (n = 12), 68 μM (n = 16). IWP-2: DMSO (n = 24), 1 μM (n = 10), 5 μM (n = 16). SU5402 + IWP-2: DMSO (n = 9), 68 μM + 5 μM (n = 9). Replicates are from >3independent experiments