Movie 1

Time lapse series of endothelial network assay. Series of images taken at 10 min intervals from 0 to 3920 min (65 hours) as indicated on each image. Images run at 10fps. The first faintly red fluorescent SOX17⁺ cells are seen from 360 min (6 hours) and are obvious from 720 min (12 hours) onwards. Blood cells appear from 2160 min (36 hours). Scale bar, 100μm. Related to Fig. 2.