Loss of cadherin 2 reduces the effectiveness and coherence of cell motion in the zebrafish tailbud. (A,B) cdh2 mutants have morphologically abnormal tailbuds (A) and tails (B). (C-J) Quantitative analysis of cell motion in the tailbud of three wild-type embryos (C-F) and three cdh2 mutants (G-J). (G) MSD is reduced in the DM of cdh2 mutants (P<0.05). (H) Polarization is reduced in the DM (P<0.05), PZ (P<0.05) and PSM (P<0.05) of cdh2 mutants. (I) Correlation length is lower in the DM (P<0.05). (J) Neighbor similarity is diminished in the DM of cdh2 homozygotes. (K-N) Adherens junctions in the PZ are visualized by immunohistochemistry for β-catenin. All panels are at the same magnification; scale bar: 5 μm. The lattice of adherens junctions among cells is present in wild-type embryos (K) but is disrupted in cdh2 mutants (L). The pattern of adherens junctions in notum1a-overexpressing embryos (M) and SU5402-treated embryos (N) resembles the wild-type pattern. P-values calculated via Student′s t-test.
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