Dual-specificity phosphodiesterase GbpB (GbpB)

GbpB (also known as PdeE) is a class II dual-specificity phosphodiesterase found in the social amoeba Dictyostelium discoideum. It is a member of the metallo-beta-lactamase superfamily, characterized by a Zn2+-dependent hydrolase catalytic domain and two cyclic nucleotide-binding (cNB) domains. GbpB primarily hydrolyzes cAMP but also shows activity toward cGMP, playing a vital role in regulating the intracellular concentrations of these second messengers during the multicellular stages of development. Unlike mammalian class I PDEs, GbpB is insensitive to common inhibitors such as IBMX, making it a distinct target for studying non-canonical signaling pathways. Inactivation of GbpB leads to significantly elevated cAMP levels and a sporogeneous phenotype, underscoring its importance in the transition from vegetative growth to multicellular differentiation.

Other names

PdeEcGMP-binding protein BCyclic nucleotide-binding protein BDual-specificity phosphodiesterase E

Hydrolysis of cAMP and cGMP