Fig. 5. Inhibition of Ena/VASP function disrupts somite rotation and leads to expanded somite area. (A-D) Dorsal explants of stage 22 embryos were co-stained for 12/101 (A,C; red in B,D) to visualize somite morphology and GFP (green in B,D) to visualize FP₄-mito and AP₄-mito expression. Expression of FP₄-mito (A,B) resulted in disruption of somite organization and cohesion, whereas somite morphology appeared normal in AP₄-mito (C,D) expressing embryos. Scale bar: 100 µm. (E) Percentage of stage 22 embryos showing normal somite morphology and mild or major disruption of somites, as assessed by 12/101 immunostaining. Results are pooled from three independent experiments; n=24-33 embryos/group. Anterior is at the top in A-D. (F-I) Somite area is increased and cells are misoriented in FP₄-mito (F,G), but not AP₄-mito (H,I) injected embryos. Scale bar: 100 µm. (J) Quantitative analysis of cross-sectional area of somites from uninjected, AP₄-mito or FP₄-mito injected embryos reveals that inhibition of Ena/VASP results in a significant increase in somite area (see Materials and methods). ^*P<0.001 (Student's t-test). Error bars indicate s.e.m. Results shown in graph are from four independent experiments, n=10-14 embryos per treatment group.