PKA R2: Proteins and Enzymes

PKA (or cAPK) is a cyclic AMP-dependent protein kinase. When activated by the second messenger cAMP, PKA mediates diverse cellular mechanisms, including proliferation, ion transport, regulation of metabolism, and gene transcription (1,2). PKA is comprised of two dimers of two subunits, R (regulatory) and C (catalytic). Two families of R subunits (RI and RII) have been identified, each possessing distinct cAMP binding properties and resulting in different phosphorylation states (2,3).