Fig. 1.

Embryonic wound healing comprises distinct temporal phases. (A) Time-lapse series of superficial and deep wound closure in blastula stage embryos. pw, post wounding. (B) Quantification of wound closure speed in superficial and deep wounds. Data are means ± s.d. of three independent experiments, n = 5 embryos for each experiment. Two-way ANOVA was performed to confirm significance. *P<0.05. (C) H&E staining of a deep wound at 1 hour after wounding. Blue dashed line represents boundary between superficial (epithelial) layer and deep (mesenchymal) layer on the animal cap. Red dashed line indicates border between the animal cap cells and vegetal cells of the embryo. Note that the deep layer has healed close by this time point, whereas the superficial layer has not yet healed. (D) Circumferential actin cable at the wound edge 10 minutes post wounding in GFP-moesin-injected embryo. Inset shows thick actin cable with few or no filopodial protrusions. (E) Filopodia formation at the wound edge 60 minutes after wounding in GFP-injected embryo. Inset shows proximal wound fronts with filopodia. Arrows indicate filopodia extended from opposing wound edges. w, wound area; ep, epithelium. (F) Quantification of the density (number of filopodia per 100 µm) and length of filopodia at the wound edge in early and late phases (means ± s.e.m.; ***P<0.001. (G) Time course of immunofluorescence staining for Ser19 phosphorylation on myosin-2 light chain in transected wounds. w, wound; bl, blastocoel; ep, epithelium. Scale bars: 500 µm (A), 50 µm (C,G), 10 µm (D,E).