Transient binding and dissipation in cross-linked actin networks.
In contrast with entangled actin solutions, transiently cross-linked actin networks can provide highly elastic properties while still allowing for local rearrangements in the microstructure-on biological relevant time scales. Here, we show that thermal unbinding of transient cross-links entails local stress relaxation and energy dissipation in an intermediate elasticity dominated frequency regime. We quantify the viscoelastic response of an isotropically cross-linked actin network by experimentally tuning the off rate of the transiently cross-linking molecules, their density, and the solvent viscosity. We reproduce the measured frequency response by a semiphenomenological model that is predicated on microscopic unbinding events.
Lehrstuhl für Biophysik E27, Technische Universität München, Germany.
O
O
Lieleg
M M A E
MM
Claessens
Y
Y
Luan
A R
AR
Bausch
D000199:Actins / Q000378:metabolism*; D000818:Animals; D003432:Cross-Linking Reagents / Q000494:pharmacology*; D004548:Elasticity / Q000187:drug effects; D015879:Myosin Subfragments / Q000378:metabolism; D011485:Protein Binding / Q000187:drug effects; D011817:Rabbits; D014783:Viscosity / Q000187:drug effects
D000199:Actins; D003432:Cross-Linking Reagents; D015879:Myosin Subfragments