Fig. S6.

Free energy as a function of cell–cell separation (in units of the thermal energy kT, per protein). The DPE function was calculated using the experimental levels $X_i\left(r\right)$ of the secreted proteins, and the calculated protein levels at the steady state $X_i^0\left(r\right)$. Dots: experimental results computed as described in Surprisal Analysis, Free Energy as a Function of Cell–Cell Separation. Curve: a polynomial fit showing the harmonic potential about the minimum at 200 μm and the low value at very short distances, likely reflecting cell–cell adhesion.