Poorly Understood Aspects of Striated Muscle Contraction

Figure 8

Tentative model. The elastic element is represented by bending of the lever arm being an integral part of the myosin head. This elastic element is stretched by a small amplitude structural change in the catalytic domain (from left to right). The schematic illustration is for isometric contraction. The position of the lever arm at elastic equilibrium of the main force-generating state (right) is illustrated by the lever arm drawn in dashed lines. The force-generating transition from left to right is orthogonal to the phosphate release step (vertical).