The article discusses the importance of understanding the roles of two intracellular cAMP receptors, PKA and EPAC, in multi-cellular eukaryotic organisms. Both PKA and EPAC are activated by an increase in intracellular cAMP levels, and their specific roles need to be carefully studied in different model systems. The lack of EPAC-specific pharmacological probes is a challenge in further elucidating the mechanism of cAMP signaling, but identifying regulators of EPAC may lead to new therapeutic strategies for major human pathological conditions such as diabetes, heart disease, and cancer. Is the molecule effective to this assay?