Phosphorylation of calf thymus RNA polymerase II by nuclear cyclic 3',5'-AMP-independent protein kinase.
Nucleoplasmic RNA polymerase II (nucleosidetriphosphate:RNA nucleotidyltransferase, EC 2.7.7.6) from calfthymus is phosphorylated by homologous cyclic AMP-independent protein kinase (ATP:protein phosphotransferase, EC 2.7.1.37). Polyacrylamide gel electrophoresis of the 32P-labeled RNA polymerase II under non-denaturing conditions revealed that both forms of the enzyme were phosphorylated. Polyacrylamide gel electrophoresis of the 32P-labeled RNA polymerase II under denaturing conditions showed that the 25 000 dalton subunit was the phosphate acceptor subunit. Partial acid hydrolysis of the 32P-labeled RNA polymerase II followed by ion-exchange chromatography revealed serine and threonine as the [32P]phosphate acceptor amino acids. Phosphorylation of the RNA polymerase II was accompanied by a stimulation of enzymatic activity and was dependent upon the presence of ATP.
D000266:Adenylyl Imidodiphosphate / Q000494:pharmacology; D000818:Animals; D002417:Cattle; D002467:Cell Nucleus / Q000201:enzymology; D000242:Cyclic AMP / Q000378:metabolism; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism*; D004789:Enzyme Activation; D010710:Phosphates / Q000378:metabolism*; D011494:Protein Kinases / Q000378:metabolism*; D012319:RNA Polymerase II / Q000302:isolation & purification / Q000378:metabolism*; D012694:Serine / Q000378:metabolism; D013912:Threonine / Q000378:metabolism; D013950:Thymus Gland / Q000201:enzymology
D010710:Phosphates; D000266:Adenylyl Imidodiphosphate; D013912:Threonine; D012694:Serine; D000242:Cyclic AMP; D011494:Protein Kinases; D012319:RNA Polymerase II; D012321:DNA-Directed RNA Polymerases