Table 3.

Reactions and kinetic parameters

#	Reaction	Rate constants	Value	References
1	cAMP $\stackrel{{\text{k}}_{\text{on,PDE}};\text{PDE}}{\to }$ AMP	kon,PDE	0.15 μM−1 s−1	(54)
2	2PKAcat + 2PKAreg$\underset{{\text{ k}}_{\text{off,PKA}}}{\overset{{\text{ k}}_{\text{on,PKA}}}{\rightleftharpoons }}$ PKA	kon,PKA	10 μM−3 s−1	estimated
		koff,PKA	6 × 10−4 s−1
3	PKA + 4cAMP $\stackrel{{\text{ k}}_{\text{on,C}1}}{\to }$ C1	kon,C1	0.0261 s−1	(49,55)
		km,PKA	5.2 μM
4	C1 $\stackrel{{\text{ k}}_{\mathrm{deg}}}{\to }$ 2PKAcat,1 + 2PKAreg + 4cAMP	kdeg	0.21 s−1	(32)
5	PKA cat,1$\stackrel{{\text{ k}}_{\mathrm{deg},1}}{\to }$ PKAcat	kdeg,1	0.0051 s−1	(49)
6	Epac + cAMP $\underset{{\text{ k}}_{\text{off,Epac}}}{\overset{{\text{ k}}_{\text{on,Epac}}}{\rightleftharpoons }}$ Epacon	kon,Epac	0.031 s−1 (estimated)	(49,56)
		koff, Epac	0.00651 s−1
		km,Epac	30 μM
7	Epacon + RAP1GDP$\underset{{\text{k}}_{\text{off,RAP}1}}{\overset{{\text{k}}_{\text{on,RAP}1}}{\rightleftharpoons }}$ RAP1GTP	kon,RAP1	0.05 μM−1 s−1 (estimated)	(52)
		koff,RAP1	1.166 10−4 s−1
8	RAP1GTP + ERK ppERK	kon,ERK	0.88 μM−1 s−1	(57,58)
		koff,ERK	0.088 s−1
9	ppERK + ppERK $\underset{{\text{ k}}_{\text{off,dimer}}}{\overset{{\text{ k}}_{\text{on,dimer}}}{\rightleftharpoons }}$ ERKdimer	kon,dimer	0.2 μM−1 s−1	estimated based on Kd = 7.5 nM (59)
		koff, dimer	0.0015 s−1