Go Back cAMP-dependent protein kinase, regulatory subunit I alpha (PKA, RIalpha)

Product Detail

cAMP-dependent protein kinase (PKA) is an ubiquitous serine/theonine protein kinase present in a variety of tissues (e.g. brain, skeletal muscle, heart). The intracellular cAMP level regulates cellular responses by altering the interaction between the catatytic C and regulatory R subunits of PKA. The inactive tetrameric PKA holoenzyme R2C2 is activated when cAMP binds to R2, which dissociates the tetramer to R2*cAMP4 and two active catalytic subunits. Free Catalytic subunits of PKA can phosphorylate a wide variety of intracellular target proteins. In response to hormone-induced high cAMP levels, PKA phosphorylates glycogen synthetase (inhibition of the enzyme activity) and phosphorylase kinase to block glycogen synthesis. Different isoforms of catalytic and regulatory subunits suggest specific functions. The recombinant RIalpha regulatory subunit supplied by Biaffin is a 86 kDa dimeric protein (monomer 43 kD). Dimeric protein specifically inhibiting PKA catalytic subunit (Ki about 0.1nM). Activity can be restored by adding cAMP. The binding of the catalytic subunit is dependent on the presence of ATP and Mg.