Actomyosin II interaction modulates cell cortex stability

Myosin II controls the viscoelastic behavior of actin filaments, interacting with actin in an energy-dependent manner. Replacing adenosine triphosphate with adenosine diphosphate changes actomyosin sliding to cross-linking. Rheological measurements show a 3-4-fold increase of the elastic portion G′ in actin filaments when myosin II is present at a molar ratio rMA=1:200. This observation is supported by the demonstration of inactive myosin heads along actin filaments using atomic force microscopy.