title: Mechanics of individual keratin bundles in living cells.
abstract: Along with microtubules and microfilaments, intermediate filaments are a major component of the eukaryotic cytoskeleton and play a key role in cell mechanics. In cells, keratin intermediate filaments form networks of bundles that are sparser in structure and have lower connectivity than, for example, actin networks. Because of this, bending and buckling play an important role in these networks. Buckling events, which occur due to compressive intracellular forces and cross-talk between the keratin network and other cytoskeletal components, are measured here in situ. By applying a mechanical model for the bundled filaments, we can access the mechanical properties of both the keratin bundles themselves and the surrounding cytosol. Bundling is characterized by a coupling parameter that describes the strength of the linkage between the individual filaments within a bundle. Our findings suggest that coupling between the filaments is mostly complete, although it becomes weaker for thicker bundles, with some relative movement allowed.
authors.affiliation: Institute for X-Ray Physics, Georg-August-Universität Göttingen, Göttingen, Germany; Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany.
authors.forename: Jens-Friedrich
authors.initials: JF
authors.lastname: Nolting
authors.affiliation: Max Planck Institute of Experimental Medicine, Department of Neurogenetics, Göttingen, Germany; Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany.
authors.forename: Wiebke
authors.initials: W
authors.lastname: Möbius
authors.affiliation: Institute for X-Ray Physics, Georg-August-Universität Göttingen, Göttingen, Germany; Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany. Electronic address: sarah.koester@phys.uni-goettingen.de.
authors.forename: Sarah
authors.initials: S
authors.lastname: Köster
mesh_terms: D001696:Biomechanical Phenomena; D045744:Cell Line, Tumor; D002470:Cell Survival; D019245:Compressive Strength; D004548:Elasticity; D006801:Humans; D007633:Keratins / Q000737:chemistry* / Q000648:ultrastructure; D008856:Microscopy, Fluorescence
chemical_list: D007633:Keratins