title: Dissociation and reassociation of rabbit skeletal muscle myosin.
abstract: Whereas dissociation of rabbit skeletal muscle myosin light chains occurs at an increased temperature (25 degrees) and in the absence of divalent cations, reassociation of the myosin oligomer requires a low temperature (4 degrees C) and the presence of divalent cations, thus resulting in the original light to heavy chain stoichiometry. With a 5-10 per cent release of alkali light chains, LC1 and LC3, and a 50 per cent dissociation of the Ca2+ binding light chain, LC2, there is no significant decrease in myosin ATPase activity irrespective of the cation activator, however, there is an approximate 15-20 per cent decrease in actomyosin ATPase activity. With reassociation of the myosin oligomer, actomyosin ATPase activity is partially restored as well as the original number of Ca2+ binding sites.
mesh_terms: D000251:Adenosine Triphosphatases / Q000032:analysis; D000818:Animals; D002118:Calcium; D004591:Electrophoresis, Polyacrylamide Gel; D007700:Kinetics; D046911:Macromolecular Substances; D009132:Muscles / Q000201:enzymology*; D009218:Myosins; D011485:Protein Binding; D011489:Protein Denaturation; D011817:Rabbits
chemical_list: D046911:Macromolecular Substances; D000251:Adenosine Triphosphatases; D009218:Myosins; D002118:Calcium