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Fig. 3
Convergence and extension movements are affected in dscr5 morphants. (A-D2) Transplantations of RLDx-labeled cells from the margin of shield stage embryos injected with CoMO or dscr5MO to the corresponding region in wild-type recipients. (A) A 6 hpf recipient embryo with CoMO-injected cells. (B,B′) Dorsal (B) and lateral (B2) views of the embryo in A developed to 10 hpf. (C) A 6 hpf recipient embryo with dscr5MO-injected cells. (D,D′) Dorsal (D) and lateral (D2) views of the embryo in C developed to 10 hpf. (E-N) Analysis of the convergence of lateral mesendodermal cells (E-I) and the extension of axial mesendodermal cells (J-N) in embryos injected with CoMO (E,F,J,K) or dscr5MO (G,H,L,M) using a photo-conversion strategy. (E-I) Labeled lateral mesendodermal cells at the shield stage in embryos injected with CoMO (E) or dscr5MO (G) were analyzed at the bud stage (F,H,I). Lateral view for all embryos except the inset in I, which is an animal pole view showing the angle between the labeled cells and the line perpendicular to the dorsoventral axis (green arrow). (J-N) Labeled axial mesendodermal cells at the shield stage in embryos injected with CoMO (J) or dscr5MO (L) were analyzed at the bud stage (K,M,N). Lateral view for all embryos; the inset in N shows the angle between the most anterior and the most posterior labeled cells (green arrow). Green dot represents the center of the images. Quantification of the convergence of lateral cells (I) and the extension of dorsal cells (N) was performed using five embryos for each condition. Asterisks indicate statistically significant differences (P<0.001, Student′s t-test), error bars indicate standard deviation. D, dorsal region; V, ventral region. (O,P) Analysis of cell intercalation in the notochord by confocal microscopy. Representative images from a control embryo (O) and a dscr5 morphant (P) at the bud stage.