Phosphorylation of type-L pyruvate kinase in intact hepatocytes. Localisation of the phosphorylation site in response to both glucagon and the Ca2+-linked agonist phenylephrine.
Pyruvate kinase is one of the enzymes which can be phosphorylated by stimulation of the cell with either glucagon or Ca2+-linked hormones. Whether these two classes of hormones phosphorylate the same site on the enzyme is unclear. Our results demonstrate that isolation of [32P]phosphorylated type-L pyruvate kinase from glucagon-treated hepatocytes followed by aspartyl-prolyl cleavage yields a [32P]phosphorylated peptide of Mr 17,000. This fragment is also phosphorylated in response to the Ca2+-mediated agonist phenylephrine.
D000262:Adenylyl Cyclases / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D002118:Calcium / Q000502:physiology*; D000242:Cyclic AMP / Q000502:physiology; D004789:Enzyme Activation / Q000187:drug effects; D005934:Glucagon / Q000494:pharmacology*; D008099:Liver / Q000201:enzymology*; D010656:Phenylephrine / Q000494:pharmacology*; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism; D011770:Pyruvate Kinase / Q000378:metabolism*; D051381:Rats
D010656:Phenylephrine; D005934:Glucagon; D000242:Cyclic AMP; D011494:Protein Kinases; D011770:Pyruvate Kinase; D000262:Adenylyl Cyclases; D002118:Calcium