PRKACB Human

Protein Kinase CAMP-Dependent Catalytic Beta (PRKACB) belongs to the Ser/Thr protein kinase family and is a catalytic subunit of cAMP-dependent protein kinase. cAMP is a signaling molecule imperative for various cellular functions. cAMP activates the cAMP-dependent protein kinase, which transduces the signal by way of phosphorylation of different target proteins. The inactive kinase holoenzyme is a tetramer composed of 2 regulatory and 2 catalytic subunits. cAMP triggers the dissociation of the inactive holoenzyme into a dimer of regulatory subunits bound to 4 cAMP and 2 free monomeric catalytic subunits. PRKACB mediates cAMP-dependent signaling initiated by receptor binding to GPCRs. PKA activation regulates various cellular processes such as cell proliferation, the cell cycle, differentiation and regulation of microtubule dynamics, chromatin condensation and decondensation, nuclear envelope disassembly and reassembly, in addition to regulation of intracellular transport mechanisms and ion flux. PRKACB regulates the abundance of compartmentalized pools of its regulatory subunits via phosphorylation of PJA2 which binds and ubiquitinates these subunits, leading to their consequent proteolysis.