Molecular origin of strain softening in cross-linked F-actin networks.
Two types of measurement are presented that relate molecular events to macroscopic behavior of F-actin networks. First, shear modulus is measured by oscillating an embedded microbead. Second, a microbead is translated at constant rate and transitions in the resisting force are observed. The loading rate dependence of the force at the transitions is similar to that of the molecular unbinding force, suggesting that they share a common origin. Reversibility tests of shear modulus provide further evidence that strain softening of F-actin networks is caused by force-induced rupture of cross-links.
Lee
Hyungsuk
H
Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Ferrer
Jorge M
JM
Lang
Matthew J
MJ
Kamm
Roger D
RD
D000199:Actins / Q000737:chemistry* / Q000648:ultrastructure*; D003198:Computer Simulation; D003432:Cross-Linking Reagents / Q000737:chemistry; D055119:Elastic Modulus; D006244:Hardness; D008956:Models, Chemical; D008958:Models, Molecular; D046912:Multiprotein Complexes / Q000737:chemistry / Q000648:ultrastructure; D011487:Protein Conformation; D013314:Stress, Mechanical
D000199:Actins; D003432:Cross-Linking Reagents; D046912:Multiprotein Complexes