DEV02387 Supplementary Material

Files in this Data Supplement:

• Supplemental Figure 1 -

  Fig. S1. Localised activation of MAPK activity at the onset of gastrulation. ERK activity is detected with a dorsoventral gradient of activity in the mesendoderm progenitors by anti di-phosphorylated ERK antibody during different stages of development. (A) Dome stage, (E) 30% epiboly, (B,F) shield stage. (C) ERK activity is expanded towards the animal pole in ERK2*-injected embryos and is completely lost in SU5402-treated embryos (G). (D,H) sprouty4 expression at 60% epiboly. (H) Treatment with SU5402 induced the complete loss of sprouty4 expression.

• Supplemental Figure 2 -

  Fig. S2. Flat preparations of the blastoderm after whole-mount in situ hybridization. sox17 expression at 80% epiboly stage in wild-type embryos (A; average number, 437; n=14) or embryos injected at the one-cell stage with DN-Ras RNA at 300 ng/ml (B; average number, 354; n=15) or co-injected with noggin and DN-Ras RNA (C; average number, 652; n=15)

• Supplemental Figure 3 -

  Fig. S3. Induction of sox17 in response to overexpression of Cas-WT or Cas-S47A RNAs injected at 10 ng/ml into one animal blastomere at the 16-cell stage. (A-C) Results of three independent experiments. (D,E) Co-injection with ERK* RNA at 50 ng/ml decreases the ability of Cas-WT to induce sox17 (D). However, Cas-S47A is insensitive to overexpression of ERK2* (E).