The heat-labile inhibitor of casein kinases 1 and 2 from rat liver cytosol (J.F. Bertomeu et al., FEBS Lett., 124, 262-264) has been purified extensively and characterized. Analysis by gel filtration and SDS-polyacrylamide gel electrophoresis suggest that the inhibitor has an Mr of 30,000. It did not contain glycosaminoglycans, oligonucleotides or neutral sugars and was totally inactivated by digestion with trypsin. Besides casein kinases, the inhibitor also inhibited the catalytic subunit of cAMP-dependent protein kinase to the same extent. The data suggest that the inhibitor is a monomeric protein that could modulate intracellular protein phosphorylation by both casein kinases and cAMP-dependent protein kinase. © 1982.
|Journal||Biochemical and Biophysical Research Communications|
|Publication status||Published - 16 Jul 1982|