Dependence of myosin filament structure on intracellular calcium concentration in skeletal muscle.

ABSTRACT: Contraction of skeletal muscle is triggered by an increase in intracellular calcium concentration that relieves the structural block on actin-binding sites in resting muscle, potentially allowing myosin motors to bind and generate force. However, most myosin motors are not available for actin binding because they are stabilized in folded helical tracks on the surface of myosin-containing thick filaments. High-force contraction depends on the release of the folded motors, which can be triggered by stress in the thick filament backbone, but additional mechanisms may link the activation of the thick filaments to that of the thin filaments or to intracellular calcium concentration. Here, we used x-ray diffraction in combination with temperature-jump activation to determine the steady-state cal

SUBMITTER: Caremani M 

PROVIDER: S-EPMC10533363 | biostudies-literature | 2023 Dec

REPOSITORIES: biostudies-literature