Fig. 2. Inhibition of FoxF1 function results in impaired gut morphogenesis. (A) Western blot analysis of FoxF1 protein tagged with a Myc epitope at the C-terminus using anti-Myc antibody. Translation of UTR FoxF1-Myc was blocked in the presence of FoxF1 morpholino (FoxF1Mo), but not by standard control morpholino (CoMo). Translation of FoxF1-Myc RNA lacking the 5' UTR sequences was not inhibited by either CoMo or FoxF1Mo. (B) The ventral view of 5-day-old (stage 45/46) uninjected embryo and embryo injected with FoxF1Mo (2.2 pmol) into two ventral blastomeres at the 8-cell stage (C). Embryos injected with FoxF1Mo display gut elongation and looping defects. (D) The ventral view of 7-day-old (stage 46/47) uninjected and FoxF1Mo-injected embryos (E), showing that knockdown embryos still do not display normal gut morphogenesis. (F) The ventral view of stage 46/47 embryos injected with CoMo (2.2 pmol) showing normal gut morphogenesis. FoxF1Mo (2.2 pmol) injected embryos with mutant gut (G), can be rescued by co-injection of FoxF1 RNA (1.25 ng) (H).