FIGURE 6.

PKA and Epac pathways are required for cAMP-mediated Akt inhibition. Specific PKA (300 μm N⁶-benzoyladenosine-3′,5′-cyclic monophosphate; cA) and Epac (300 μm 8-(4-methoxyphenylthio)-2′-O-methyladenosine-3′,5′-cyclic monophosphate; cE) analogs were used alone or in combination to assess their relative contribution to cAMP-mediated Akt inhibition. Bottom, quantitation (phospho-Akt/total Akt) from three independent experiments (A). EpacR279E was co-transfected with HA-Akt. Upon stimulation, HA-Akt was immunoprecipitated, and its phosphorylation state was analyzed with the indicated antibody (B). Quantitation (phospho-Ser⁴⁷³-Akt/HA-Akt) from two independent experiments is shown. FK, forskolin.