Fig. 5.

Illustration of the mechanism for transient patterning with hysteresis. Transient evolution of extracellular BMP (a) and BR (b) leads to a spatial bistability and low extracellular levels of BMP at steady state. (c) The same as in a except the extracellular BMP levels drop more rapidly after the same initial 30 min of patterning imposed in this case by reducing the BMP input to 2% of WT. The steady-state levels of extracellular BMP in a and c are very similar. (d) However, due to the lower exposure of BMP over time, all cells return to the lower solution branch.