※ PKA family introduction

    PKA (cAMP-dependent protein kinase) belong to AGC family. PKA is characterized by its role as important downstream effecter of second messenger cAMP. PKA consist of multiple forms of regulatory and catalytic subunits and PKA holoenzyme contain two regulatory subunits and two catalytic subunits, which determines the biochemical and functional features. PKA keeps catalytically inactive under low levels of cAMP, PKA obtain its catalytic activity only after binds to the two binding sites on regulatory subunits. PKA involve in a varieties of cellular processes through phosphorylation of different nuclear and cytoplasmic substrates, including metabolism, differentiation, synaptic transmission, ion channel activity, growth and development (1).

Reference
1. Feliciello, A., Gottesman, M.E. and Avvedimento, E.V. (2005) cAMP-PKA signaling to the mitochondria: protein scaffolds, mRNA and phosphatases. Cell Signal, 17, 279-287. PMID: 15567059