Non-linear actomyosin elasticity in muscle? (Biophysical Journal)

Cyclic interactions between myosin II motor domains and actin filaments that are powered by turnover of ATP, underlie muscle contraction and have key roles in motility of non-muscle cells. The elastic characteristics of actin-myosin cross-bridges are central in the force-generating process and disturbances in these properties may lead to disease. Whereas the prevailing paradigm is that the cross-bridge elasticity is linear (Hookean), recent single molecule studies suggest otherwise. Despite convincing evidence for substantial non-linearity of the cross-bridge elasticity in the single molecule work, this finding has had limited influence on muscle physiology and physiology of other ordered cellular actin-myosin ensembles.