Blocking Bmp reduces the Fgf signaling response in the forming pouch. Still images from confocal time-lapse movies of sox17:dsred; dusp6:d2GFP (Fgf-responsive cells) double-transgenic embryos. (A-A′′,F-F′′) Embryos at 18hpf, the initiation of the movie (T0). Arrows indicate overlap between transgene expression, whereas arrowheads indicate lack of overlap. (F-J′′) Dorsomorphin-treated embryos show a reduced Fgf signaling response in the endoderm and pouches fail to form, in contrast to controls (A-E′′). Lateral views, anterior to the left. Scale bar: 50µm.