Movie 1.

3D animation generated from z-stacks obtained with light sheet microscopy of an E9.5 Wt1^CreERT2/+; Rosa26^mTmG/+ embryo after Tam at E8.5. The membrane-bound dTomato appears in red (561 nm) to illustrate the body structure and the GFP-positive cells appear in green. GFP-positive cells were labelled using the Imaris software according to their location: in the mesentery - white spots; in the proepicardium and within the trunk area - blue spots; in the neural tube - yellow spots; in the lateral plate mesoderm - green spots.