title: Fragility and mechanosensing in a thermalized cytoskeleton model with forced protein unfolding.
abstract: We describe a model of cytoskeletal mechanics based on the force-induced conformational change of protein cross-links in a stressed polymer network. Slow deformation of simulated networks containing cross-links that undergo repeated, serial domain unfolding leads to an unusual state-with many cross-links accumulating near the critical force for further unfolding. This state is robust to thermalization and does not occur in similar protein unbinding based simulations. Moreover, we note that the unusual configuration of near-critical protein cross-links in the fragile state provides a physical mechanism for the chemical transduction of cell-level mechanical strain and extra-cellular matrix stiffness.
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Brenton D
authors.initials: BD
authors.lastname: Hoffman
authors.forename: Gladys
authors.initials: G
authors.lastname: Massiera
authors.forename: John C
authors.initials: JC
authors.lastname: Crocker
mesh_terms: D003198:Computer Simulation; D003598:Cytoskeletal Proteins / Q000737:chemistry* / Q000502:physiology*; D003599:Cytoskeleton / Q000737:chemistry* / Q000502:physiology*; D004548:Elasticity; D040542:Mechanotransduction, Cellular / Q000502:physiology*; D008954:Models, Biological; D008956:Models, Chemical; D008958:Models, Molecular; D009038:Motion; D017510:Protein Folding; D013314:Stress, Mechanical
chemical_list: D003598:Cytoskeletal Proteins