Regulation of IP3 receptors by cyclic AMP

Ca2+ and cAMP are ubiquitous intracellular messengers and interactions between them are commonplace. Here the effects of cAMP on inositol 1,4,5-trisphosphate receptors (IP(3)Rs) are briefly reviewed. All three subtypes of IP3R are phosphorylated by cAMP-dependent protein kinase (PICA). This potentiates IP3-evoked Ca2+ release through IP(3)R1 and IP(3)R2, but probably has little effect on IP(3)R3. In addition, cAMP can directly sensitize all three IP3R subtypes to IP3. The high concentrations of CAMP required for this PICA-independent modulation of IP(3)Rs is delivered to them within signalling junctions that include type 6 adenylyl cyclase and IP(3)R2. (C) 2016 The Author. Published by Elsevier Ltd.