Fig. 5. Failure of convergent extension in the definitive endoderm of chato mutants. (A-D) Wild-type (A,B) and chato mutant (C,D) 8-somite stage mouse embryos hybridized with Ttr probes to highlight extraembryonic visceral endoderm (blue) and definitive endoderm (exterior layer of embryonic tissues in white). ext, white extraembryonic tissue. (A,C) Lateral views; (B,D) anterior views. (E-G) Plots of (E) wild-type (blue) and chato (red) definitive endoderm length (µm), (F) wild-type (green) and chato (red) definitive endoderm width (µm), and (G) definitive endoderm length-to-width ratio (LWR) in wild-type (gray) and chato mutant (red) embryos. Error bars indicate s.d. ^*P<0.05, ^**P<0.01. (H) Length and width average measurements ±s.d. in µm. The number of embryos analyzed for each stage is indicated (# embryos); na, not assayed.