Table 5. Equilibrium conditions for the Minimal Model of WNT signaling.

All rates are multiplied with factor R=20, so that the equilibrium is reached at 4.5 hr according to Figure 4C–D.

Rate constant		Biological process	Values based on	Wnt off	Wnt on
b	nMmin−1	CTNNB1 synthesis	$v_{12}$ from Lee	0.423	0.423
$\frac{k_2}{k_1}$	nM	Binding to and phosphorylation by the destruction complex of cytoplasmic CTNNB1	$\text{K8}$ from Lee	120	120
$k_3$	min−1	Dissociation and degradation of phosphorylated CTNNB1 from the destruction complex	Deduced from $b$ and $x_3$	0.0068	0.0068
$\frac{k_5}{k_4}$	nM	Inactivation of the destruction complex by activated DVL	Fitted to $x_1$ and $x_7$	N.A.*	1.7
$\frac{k_6}{k_7}$		Ratio between nuclear import and export of CTNNB1	Deduced from $x_1$ and $x_5$	0.96	1.17
$\frac{k_9}{k_8}$	nM	Dissociation of nuclear CTNNB1 from TCF	Deduced from $x_5$, ${\mathrm{T}\mathrm{C}\mathrm{F}}^0$, $x_7$	320	33.6

^*In WNT OFF, w=0, and no inactive destruction complex is formed. Only in WNT ON, w=1, which induces the formation of inactivated destruction complex at the expense of free destruction complex (see Equations 7a and 9 in the model description in Materials and methods).