A family of contractile proteins, present in striated muscle and most eukaryotic cells that combines with actin to form actomyosin, and which in striated muscle gives the A-bands their dark color. This is myosin II (a two-headed, tailed variety). Myosin I (a single-headed, tailless variety) is involved in cell locomotion. Myosin moves actin filaments by virtue of ATP-fuelled structural changes.
See Actin, Actomyosin, Adenosine triphosphosphate (ATP), Cell locomotion, Eukaroyte cell (or organism), Growth cone, Isotonic contraction, Muscle fiber, Myofibrils and myofilaments, Protein-folding problem, Proteins, Striated (or striped or voluntary) muscle