TABLE 2.

Apparent rate and equilibrium dissociation constants of GSKIP binding to RIIα and RIIβ

Surface plasmon resonance measurements using Biacore technology were performed to determine rate constants (k_a and k_d) and equilibrium binding constants (K_D) for the interaction of His-tagged GSKIP with human R subunits. RIIα and RIIβ were reversibly captured via 8-AHA-cAMP, which was covalently coupled on a CM5 sensor chip (not shown in the plot). His-GSKIP was injected over RIIα and RIIβ surfaces (Fig. 3B). Association and dissociation phases were monitored for 5 min, respectively. No binding was detected when RIα and RIβ were captured (data not shown).

	ka	kd	KD
	m−1s−1	s−1	nm
RIIα	1.3 × 105	6.6 × 10−4	5
RIIβ	2.8 × 104	1.2 × 10−3	43