Simulation movie showing a 1:1 Cdc42POL:WT sprout in which the green and red cells respectively depict Cdc42POL and WT cells. The green Cdc42POL cells are less polarized and are less competent to occupy the tip position than the red WT cells. The Cdc42POL and WT cells segregate vertically, with the Cdc42POL and WT cells respectively at the top and bottom of the vessel sprout, albeit only transiently (compare with Cdc42FIL:WT sprout in Movie 21). In contrast, the horizontal segregation of the Cdc42POL and WT cells, with the Cdc42POL cells at the rear of the sprout, occurs in a more persistent way (compare with Cdc42FIL:WT sprout in Movie 21). The green layer underneath the vessel shows the VEGF gradient, which linearly increases towards the tip.