Fig. 4. Time lapse imaging reveals blastopore lip maturation, bottle cell internalization, and blastopore closure phenotypes associated with the Wnt11 family morphants.

A. Kymographs were made from the time lapse images of the vegetal pole during gastrulation. The distance axis is the line across the vegetal pole that passed first through the center of the dorsal lip and then through the center of the eventual ventral blastopore lip. The kymographs were classified into “normal,” “mild perturbation,” and “severe perturbation.” Representative examples of the three classes are shown. In the kymographs for all three phenotypes, the dorsal bottle cells appear and move towards the center of the embryo resulting in an early lip (yellow arrowhead). In the “severe perturbation” kymographs, the movement towards the center is slower (compare i. and ii. to iii.). In the normal kymographs (i.), after the blastopore has moved further, the early lip matures and the color of the dorsal lip line changes to become lighter because the bottle cells have moved inside the embryo (dorsal green arrow). In the mild kymographs (ii.), this happens after transient reversal in the movement of the dorsal lip (dorsal green arrow). In the kymographs for all three phenotypes, the dark ventral lip line appears and also moves towards the center of the embryos (ventral green arrow). In the normal and mild kymographs, the dorsal and ventral lips continue to move closer to each other (pink arrowheads). By contrast, in the severe kymographs, the dorsal lip either reverses and moves away from the ventral line or stalls (dorsal pink arrowhead). B. Results from qualitatively scoring the kymographs from a total of five (Wnt11 family morphants) and six (sibling and control morphants) independent experiments. The Wnt11 family morphants are statistically significantly different than the control morphants and siblings (Fisher-Freeman-Halton test with BF method for multiple hypotheses; ** = p « 0.001).