The active site of myosin.

The significance of myosin has been expanded recently with the realization that it is found in every eukaryotic cell, where it has a role in cytokinesis, cell division, and vesicle transport. Advances in molecular genetics and expression systems related to myosin and actin have helped to reveal the extent of the myosin superfamily. New motility assays and techniques have provided information about the residues involved in ATP hydrolysis and the conformational change induced by nucleotide binding. The results of these techniques revealing structural and functional information combined with previous studies of the active site of myosin should provide future direction for studying this exciting and rapidly moving area of biochemistry.