Figure 6

Both PKAI and PKAII are activated to phosphorylate Kemptide but not CREB at saturating conditions of cAMP. 293T cells were co-transfected with a fixed amount (1280 ng) of either pExRIIα or pDeRIα together with pDeCα1 (300 ng) (A and B) or pDeCβ2 (1400 ng) (C and D) for 24 hours. Cell extracts were adjusted to 1 mg total protein/mL and assayed for enzyme activity (cpm,) in the presence of increasing concentrations of cAMP (0 - 5000 nM) (A and C). Identical cell extracts were assayed for relative luciferase activity (B and D). Data points represent relative enzyme activity and luciferase activity, +/- SD (n = 3-6).