A cAMP-dependent protein kinase is present in differentiating Dictyostelium discoideum cells
Gunzburg, J.; Veron, M.
EMBO Journal 1(9): 1063-1068
1982
ISSN/ISBN: 0261-4189 PMID: 16453431 Document Number: 195815
We demonstrate the occurrence of a cAMP-dependent protein kinase in Dictyostelium discoideum cells at the terminal stage of differentiation. A cAMP-binding component was purified to homogeneity by affinity chromatography. This subunit inhibits the activity of purified catalytic subunit from beef heart protein kinase; the inhibition is reversed upon addition of cAMP. The protein is highly specific for cAMP and has a dissociation constant of 4 nM. The isolated regulatory subunit is a monomer of 39 K, with a sedimentation coefficient of 3.5S and a frictional coefficient of 1.24. The differences between this regulatory subunit and regulatory subunits of protein kinases from other sources are discussed.