Movie 14.

Convergent extension and apical constriction do not show temporal overlap during neural tube closure. Time lapse recording showing cell behaviour at the posterior neural plate from stage 12.5-stage 16. Initially neuroepithelial cells undergo polarised cell intercalation. During the last phase of neural tube closure, neuroepithelial cells undergo apical constriction, marked by the reduction of their apical cell surface area and enrichment of medio-apical actin signal (yellow). Cyan: Prickle2, Yellow: Utr-GFP. Time interval = 30 sec.