Apical extrusion pf PE cells. epi:GFP;β-actin:LifeAct-RFP embryo in vivo time-lapse starting at 52 hpf with drift correction. Top panels show 3D reconstruction, bottom panels show a single 0.320 μm thick optical section. On the right green (epi:GFP) labels dorsal pericardial (DP) and proepicardial (PE) cells in green. LifeAct-RFP marks F-actin in red. On the left, movie in gray-scale, the cell outlines were traced to create masks and each color identifies a cell over time. White arrowheads point to region were a cell extrusion will take place (cell labeled in green). At this site an actin ring becomes visible (red arrowhead). Scale bar, 10 μm. Shown is a representative movie from ≥ 3 biological and ≥ 2 technical replicates.