title: Nonlinear Loading-Rate-Dependent Force Response of Individual Vimentin Intermediate Filaments to Applied Strain.
abstract: The mechanical properties of eukaryotic cells are to a great extent determined by the cytoskeleton, a composite network of different filamentous proteins. Among these, intermediate filaments (IFs) are exceptional in their molecular architecture and mechanical properties. Here we directly record stress-strain curves of individual vimentin IFs using optical traps and atomic force microscopy. We find a strong loading rate dependence of the mechanical response, supporting the hypothesis that IFs could serve to protect eukaryotic cells from fast, large deformations. Our experimental results show different unfolding regimes, which we can quantitatively reproduce by an elastically coupled system of multiple two-state elements.
authors.affiliation: Institute for X-Ray Physics, Georg-August-Universität Göttingen, 37077 Göttingen, Germany.
authors.forename: Johanna
authors.initials: J
authors.lastname: Block
authors.affiliation: Institute of Physical Chemistry, Georg-August-Universität Göttingen, 37077 Göttingen, Germany.
authors.forename: Hannes
authors.initials: H
authors.lastname: Witt
authors.affiliation: Department of Physics and Astronomy and LaserLab, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, Netherlands.|LUMICKS B.V., 1081 HV Amsterdam, Netherlands.
authors.forename: Andrea
authors.initials: A
authors.lastname: Candelli
authors.affiliation: Department of Physics and Astronomy and LaserLab, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, Netherlands.
authors.forename: Erwin J G
authors.initials: EJ
authors.lastname: Peterman
authors.affiliation: Department of Physics and Astronomy and LaserLab, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, Netherlands.
authors.forename: Gijs J L
authors.initials: GJ
authors.lastname: Wuite
authors.affiliation: Institute of Physical Chemistry, Georg-August-Universität Göttingen, 37077 Göttingen, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Janshoff
authors.affiliation: Institute for X-Ray Physics, Georg-August-Universität Göttingen, 37077 Göttingen, Germany.
authors.forename: Sarah
authors.initials: S
authors.lastname: Köster