A Mechanochemical Mechanism for Muscle Contraction

A mechanism for contraction in skeletal muscle is proposed in which the tension-generating site is located within the core of the thick (myosin) filament, specifically within the trypsin-sensitive hinge region of the myosin rod. The force-developing mechanism is thought to be the transfer of energy from ATP splitting in the globular head of one molecule directly to the hinge region of an adjoining molecule, resulting in a phase transition from crystalline to amorphous within the hinge segment of the second molecule. Binding of MgATP at the actinmyosin interface is considered to be a release mechanism. The model leads to out-of-phase oscillating movement of the cross bridges.