Light-chain movement and regulation in scallop myosin.
Photo-cross-linking techniques show that when scallop myosin or myofibrils are subjected to experimental conditions that cause relaxed muscles to go into rigor, the N-terminal portion of the regulatory light chain of myosin moves towards the essential light chain while the C-terminal portion stays in place. These changes occur on the myosin before combination with actin. Cross-linking of the N-terminal region to the essential light chain in rigor locks the myosin into a conformation such that calcium sensitivity of the actin-activated Mg-ATPase is lost.
D000199:Actins / Q000502:physiology; D000205:Actomyosin / Q000502:physiology; D000251:Adenosine Triphosphatases / Q000378:metabolism; D000818:Animals; D002118:Calcium / Q000502:physiology; D003432:Cross-Linking Reagents; D046911:Macromolecular Substances; D008974:Mollusca; D009038:Motion; D009119:Muscle Contraction; D009218:Myosins / Q000502:physiology*
D000199:Actins; D003432:Cross-Linking Reagents; D046911:Macromolecular Substances; D000205:Actomyosin; D000251:Adenosine Triphosphatases; D009218:Myosins; D002118:Calcium