Protein kinase A regulatory subunit II (PKA RII)

The protein kinase A regulatory subunit II is one of the two major types of regulatory subunits (RIIα and RIIβ, expressed from PRKAR2A and PRKAR2B genes) in the PKA holoenzyme, which is a central effector of cyclic AMP signaling. In the inactive state, PKA exists as a tetramer comprised of two regulatory subunits (type II in this case) and two catalytic subunits. The RII subunit binds cyclic AMP, causing conformational changes that release and activate the catalytic subunits for substrate phosphorylation. RII subunits are crucial for anchoring PKA to specific intracellular compartments via interactions with AKAPs, thereby fine-tuning cellular signaling. Type II regulatory subunit expression is associated with differentiation, and aberrant expression or regulation can contribute to cancer, neurological, and other diseases. Although not widely directly targeted by drugs, the subunit’s role in spatial and functional regulation of PKA places it at the center of cellular signaling networks important for disease pathogenesis and therapy.

Other names

cAMP-dependent protein kinase regulatory subunit type IIPKA RIIRIIRIIαRIIβPRKAR2APRKAR2B

Drugs generally modulate the upstream signaling (cAMP levels) or protein–protein interactions (AKAP anchoring), thereby indirectly influencing PKA RII subunits