title: The heat labile phosphatase modulator (inhibitor-2) complex from rabbit skeletal muscle.
abstract: The heat stable phosphatase modulator protein (inhibitor-2) has been shown to play a crucial role in the reversible ATP, Mg-dependent activation of a multisubstrate protein phosphatase. The modulator activity is acid and heat stable and resides in a small asymmetrical protein which, after boiling migrates in sucrose density gradient centrifugation with a molecular weight of 17K. The present report shows that in unboiled rabbit skeletal muscle preparations all the modulator activity is found associated with a heat labile protein component, which imposes an important regulatory feature on the heat stable activity. The heat labile complex migrates in sucrose density gradient centrifugation as a Mr = 70K protein.
mesh_terms: D000818:Animals; D002499:Centrifugation, Density Gradient; D055598:Chemical Phenomena; D002621:Chemistry; D004791:Enzyme Inhibitors / Q000302:isolation & purification*; D006358:Hot Temperature; D009124:Muscle Proteins / Q000302:isolation & purification*; D009132:Muscles / Q000201:enzymology*; D010765:Phosphorylase Phosphatase / Q000037:antagonists & inhibitors / Q000302:isolation & purification; D011506:Proteins; D011817:Rabbits; D000097847:Protein Phosphatase Inhibitory Proteins
chemical_list: D004791:Enzyme Inhibitors; D009124:Muscle Proteins; D010765:Phosphorylase Phosphatase; D011506:Proteins; C024833:protein phosphatase inhibitor-2; D000097847:Protein Phosphatase Inhibitory Proteins