The molecular mechanism of force generation in striated muscle.

An electrostatic mechanism for force generation in muscle is proposed which does not require bond formation between thick and thin filaments nor movement of the cross bridges. The myosin heads, which project from the thick filaments and touch the thin filaments, possess a high negative surface charge density. Owing to their large dielectric increment, the thin filaments are polarized by the electric field generated by the myosin heads. The polarized thin filaments tend to move toward the center of the sarcomere. Myosin ATPase activity is increased in the overlap region to maintain the negative surface potential. Thus, ATP hydrolysis provides the energy for shortening. Calculations give estimated tensions generated by this model that are comparable to those observed experimentally for vertebrate striated muscle.