DEFINITION
EPAC2 (exchange protein directly activated by cAMP, isoform 2) is a guanine-nucleotide exchange factor for Rap GTPases whose activity is directly regulated by cAMP binding, independent of protein kinase A.
In pancreatic β-cells, EPAC2 contributes to glucose-dependent insulin exocytosis downstream of GLP-1R activation, complementing the PKA pathway. The relative contribution of PKA versus EPAC2 to insulin release under different physiological contexts is an active research topic.
WHY IT MATTERS
EPAC2 defines the second, PKA-independent arm of GLP-1R signalling in β-cells.
RELATED
Compounds