Regulation of phosphorylase-phosphatase from skeletal muscle by phosphorylation of a regulator protein.
The inhibitory effect of a heat-stable regulator protein from skeletal muscle on the activity of phosphorylase-phosphatase (EC 3.1.3.17) was studied. The regulator protein was shown to be both phosphorylated and dephosphorylated in vivo as well as in vitro. The incorporation of phosphate into the regulator protein increased, while dephosphorylation decreased the ability of the protein to inhibit phosphatase activity. Our results suggest that the reversible phosphorylation of the regulator protein plays an essential role in the regulation of phosphorylase-phosphatase activity.
D000818:Animals; D004837:Epinephrine / Q000494:pharmacology; D066298:In Vitro Techniques; D009132:Muscles / Q000201:enzymology*; D010085:Oxidative Phosphorylation; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism*; D010765:Phosphorylase Phosphatase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D006005:Phosphorylases / Q000378:metabolism; D011506:Proteins / Q000378:metabolism* / Q000494:pharmacology; D011817:Rabbits
D011506:Proteins; D006005:Phosphorylases; D010765:Phosphorylase Phosphatase; D010744:Phosphoric Monoester Hydrolases; D004837:Epinephrine