Open AccessForce-history dependence and cyclic mechanical reinforcement of actin filaments at the single molecular level
Author(s) -
Hyunjung Lee,
Suzanne G. Eskin,
Shoichiro Ono,
Cheng Zhu,
Larry V. McIntire
Publication year - 2019
Publication title -
journal of cell science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.384
H-Index - 278
eISSN - 1477-9137
pISSN - 0021-9533
DOI - 10.1242/jcs.216911
Subject(s) - mechanosensitive channels , actin , cytoskeleton , actin remodeling , biophysics , actin cytoskeleton , actin remodeling of neurons , kinetics , materials science , biology , microbiology and biotechnology , biochemistry , physics , classical mechanics , receptor , ion channel , cell
Actin cytoskeleton is subjected to dynamic mechanical forces over time and the history of force loading may serve as mechanical preconditioning. The actin cytoskeleton is mechanosensitive; however, the mechanisms underlying force regulation of actin dynamics still need to be elucidated. Here, we investigated actin depolymerization under a range of dynamic tensile forces using atomic force microscopy. Mechanical loading by cyclic tensile forces induced significantly enhanced bond lifetimes and different force-loading histories resulted in different dissociation kinetics in G-actin/G-actin and G-actin/F-actin interactions. Actin subunits at the two ends of filaments formed bonds with distinct kinetics under dynamic force: cyclic mechanical reinforcement was more effective at the pointed end compared to that at the barbed end. Our data demonstrate force-history dependent reinforcement in actin-actin bonds and polarity of the actin depolymerization kinetics under cyclic tensile forces. These properties of actin may be important clues to understand regulatory mechanisms underlying actin-dependent mechanotransduction and mechanosensitive cytoskeletal dynamics.