Activation of Epac1 by cAMP Authored: May, B, 2009-05-28 03:42:50 Each molecule of Epac1 binds 1 molecule of cAMP. Epac1 binds cAMP less tightly than PKA binds cAMP so it is believed that Epac1 binds cAMP after PKA is saturated. The binding of cAMP by Epac1 activates the guanyl nucleotide exchange activity of Epac1. Epac1 has also been shown to bind the SUR1 subunit of ATP-gated potassium channels (KATP channels) in beta cells so Epac1 may participate in direct regulation of potassium transport.<br>Epac1 also interacts with the calcium sensor Piccolo in a complex with Rim2 at the cell membrane. This may influence exocytosis of insulin. Edited: May, B, 2009-05-28 03:42:50 Pubmed11071853 Pubmed12401793 Pubmed12496249 Pubmed15569269 Pubmed16613879 Pubmed16973695 Pubmed17306374 Pubmed18202100 Reactome Database ID Release 43381668 Reactome, http://www.reactome.org ReactomeREACT_18315 Reviewed: Gillespie, ME, 2009-06-02 00:59:01 Epac1 Epac1:cAMP Complex