Fig. 4

MZptk7 mutant embryos display PCP-mediated morphogenesis defects. (A,B) Lateral views of wild-type (A) and MZptk7^hsc9 mutant (B) embryos at 24 hpf. (C,D) Flat-mounts of 10- to12 somite-stage wild-type (C) and MZptk7^hsc9 (D) embryos stained for krox20 (hindbrain) and myoD (somite) gene expression. (E) Quantification of the anterior-posterior extent of the myoD expression domain in wild-type (WT) versus MZptk7^hsc9 mutant embryos (^***P<0.001, n=8 for each group). (F) Quantification of the mediolateral extent of krox20 expression in WT versus MZptk7^hsc9 mutant embryos (^***P<0.001, n=8 for each group). MZptk7^hsc9 mutant embryos display clear defects in axial extension. (G-J) Anterior (G,H) and dorsal (I,J) views of bud stage WT (G,I) and MZptk7^hsc9 (H,J) embryos stained for hgg1 (prechordal plate, pcp), dlx3 (prospective neural plate, arrowheads) and ntl (prospective notochord, n). MZptk7^hsc9 mutants demonstrate defects in the convergence of both neuroectoderm and axial mesoderm tissues. (K,L) Dorsal confocal images of the neural tube and adjacent somites of 24 hpf wild-type (K) and MZptk7^hsc9 (L) embryos, injected with membrane-localised monomeric RFP (membraneRFP) (Megason and Fraser, 2003). MZptk7^hsc9 mutant embryos display an accumulation of neural progenitors (asterisk in L) at the centre of the neural primordium. Anterior is left. (M) MembraneRFP-labelled cells in the dorsal ectoderm of WT and MZptk7^hsc9 embryos at 90% epiboly. Dorsal view, midline to the right and anterior to the top. The length-to-width (LWR) ratio of cells are as indicated for WT (n=74) and MZptk7^hsc9 (n=94). (N) Rose diagrams for cell orientation relative to the embryonic midline at 90% epiboly in WT and MZptk7^hsc9 embryos. (O) Graph showing percentage of mediolaterally aligned cells, for which longitudinal axis is oriented ±15° with respect to the embryonic mediolateral axis. (P,Q) Dorsal confocal images of the neural keel and adjacent somites of 8- to 10-somite-stage WT (P) and MZptk7^hsc9 (Q) embryos scatter-labelled with GFP-Prickle (GFP-Pk) and membrane RFP. The subcellular localisation of the PCP marker GFP-Pk is disrupted in MZptk7^hsc9. Anterior is up. Confocal imaging was carried out at the level of the first to the fifth somite pairs. (R) Quantification of the localisation of GFP-Pk puncta in WT (four embryos) versus MZptk7^hsc9 (six embryos).