Nonlinear Loading-Rate-Dependent Force Response of Individual Vimentin Intermediate Filaments to Applied Strain

Block, Johanna; Witt, Hannes; Candelli, Andrea; Peterman, Erwin J. G.; Wuite, Gijs J. L.; Janshoff, Andreas; Köster, Sarah

doi:10.1103/physrevlett.118.048101

Cited by 95 publications

(209 citation statements)

References 38 publications

Supporting

Mentioning

191

Contrasting

Order By: Relevance

“…Vimentin was labeled, reconstituted, and assembled according to previously published protocols. Labeling with ATTO647N (ATTO-Tech GmbH) and biotin-maleimide (Jena BioSciences GmbH) was performed according to Block et al 12 and Winheim et al 39 Re-constitution and assembly were performed as described by Block et al 13 Carboxylated polystyrene beads were functionalized according to Janissen et al 40 as described in Block et al 13…”

Section: Vimentin and Bead Functionalizationmentioning

confidence: 99%

See 1 more Smart Citation

Vimentin intermediate filaments undergo irreversible conformational changes during cyclic loading

Forsting

Kraxner

Witt

et al. 2019

Preprint

Self Cite

View full text Add to dashboard Cite

Intermediate filaments (IFs) are part of the cytoskeleton of eukaryotic cells and are thus largely responsible for the cell's mechanical properties. IFs are characterized by a pronounced extensibility and remarkable resilience that enable them to support cells in extreme situations. Previous experiments showed that under strain, α-helices in vimentin IFs might unfold to β-sheets. Upon repeated stretching, the filaments soften, however, the remaining plastic strain is negligible. Here we observe that vimentin IFs do not recover their original stiffness on reasonable time scales, and we explain these seemingly contradicting results by introducing a third, less well-defined conformational state. Reversibility on the nanoscale can be fully rescued by introducing crosslinkers that prevent transition to the β-sheet. Our results classify IFs as a nano-1 material with intriguing mechanical properties, which is likely to play a major role for the cell's local adaption to external stimuli.Keywords: cell mechanics, cytoskeleton, intermediate filaments, force-strain behavior, 3-state system, optical tweezers.The mechanical properties of biological cells are defined by the cytoskeleton, a composite network of microtubules, actin filaments and intermediate filaments (IF). 1,2 Although the exact division of labour among the three filament types is still not fully resolved, 1,2 there is ample evidence that IFs are the load bearing elements when cells are subjected to external tensile 3,4 or compressive 5 stress. During embryogenesis and tissue formation, in particular, cells undergo dramatic changes in shape and size. The force scales expected for cellular processes lie between single motor protein forces of a few pN, which can be measured by FRET sensors, 6 and the collective forces of several nN measured for whole cells, as determined, e.g., by traction force microscopy. 7 In order to withstand strong transitions, cells show reversible superelasticity, which is linked to their IF network. 3 In order to achieve the required material properties for IFs, nature applies design principles on the nanoscale distinct from human engineering solutions and instead relies on self-organization and structural hierarchy. As a consequence, IFs stand out among the cytoskeletal filaments by their high flexibility 8,9 and enormous extensibility. [10][11][12][13] Within the IF family, vimentin is typical for cells of mesenchymal origin. 14 Like all cytoskeletal IFs, vimentin monomers comprise an α-helical rod domain with intrinsically unstructured head and tail domains. 15 The monomers assemble following a hierarchical pathway resulting in filaments with laterally and longitudinally arranged monomers ( Fig. 1a). 16,17 Theoretical considerations, 12,13 molecular dynamics simulations 18,19 and Xray diffraction studies 20 have shown that the intriguing tensile properties of IFs originate from conformational changes on different levels of the hierarchical filament structure. no. 654148). Further financial support was received from the Deutsche Forsch...

show abstract

Section: Vimentin and Bead Functionalizationmentioning

confidence: 99%

“…As a consequence, IFs stand out among the cytoskeletal filaments by their high flexibility 8,9 and enormous extensibility. [10][11][12][13] Within the IF family, vimentin is typical for cells of mesenchymal origin. 14 Like all cytoskeletal IFs, vimentin monomers comprise an α-helical rod domain with intrinsically unstructured head and tail domains.…”

mentioning

confidence: 99%

Vimentin intermediate filaments undergo irreversible conformational changes during cyclic loading

Forsting

Kraxner

Witt

et al. 2019

Preprint

Self Cite

View full text Add to dashboard Cite

show abstract

“…3 The resulting biopolymer comprises a complex high-order arrangement of coiled coils, 3 which allows IFs to be extended up to at least 4.5-fold their initial length. [6][7][8] This enormous extensibility is in stark contrast to microtubules and F-actin. 9 Vimentin is the IF typically expressed in mesenchymal cells 2 and up-regulated during the epithelial-to-mesenchymal transition in wound healing, early embryogenesis, and cancer metastasis .…”

mentioning

confidence: 99%

“…9 Vimentin is the IF typically expressed in mesenchymal cells 2 and up-regulated during the epithelial-to-mesenchymal transition in wound healing, early embryogenesis, and cancer metastasis . 10 In addition to being highly extensible 8,11,12 vimentin is flexible [13][14][15] and stable. 16 While the extensibility describes how much a filament can be elongated before rupture, it does not imply the shape of the force-strain curve and does in particular not allow for conclusions on the linearity of this relation.…”

mentioning

confidence: 99%

Tuning Intermediate Filament Mechanics by Variation of pH and Ion Charges

Schepers

Lorenz

Köster

2019

Preprint

Self Cite

View full text Add to dashboard Cite

8The cytoskeleton is formed by three types of filamentous proteins -microtubules, actin fila-9 ments, and intermediate filaments (IFs) -and enables cells to withstand external and internal 10 forces. Vimentin is the most abundant IF in humans and has remarkable mechanical properties, 11 such as high extensibility and stability. It is, however, unclear to which extent these properties 12 are influenced by the electrostatic environment. Here, we study the mechanical properties of 13 single vimentin filaments by employing optical trapping combined with microfluidics. Force-14 strain curves, recorded at varying ion concentrations and pH values, reveal that the mechanical 15 properties of single vimentin IFs are influenced by direct (pH) and indirect (ionic) charge vari-16 ations. By combination with Monte Carlo simulations, we connect these altered mechanics to 17 electrostatic interactions of subunits within the filaments. We thus find possible mechanisms 18 that allow cells to locally tune their stiffness without remodelling the entire cytoskeleton. 19One-Sentence-Summary: Adaptable force-strain behaviour of single cytoskeletal filaments 20 in varying electostatic conditions allow cells to tune their mechanical properties rapidly and 21 locally. 22 1 MAIN TEXT 23 Introduction 24It is meanwhile well accepted that the mechanical properties of cells are, to a large extent, 25 governed by the cytoskeleton, a stabilising, yet flexible framework, which is composed of mi-26 crotubules, actin filaments, and intermediate filaments (IFs), together with motor proteins and 27 crosslinkers. While microtubules and actin filaments are conserved in eukaryotic cell types, 28 there are around 70 different genes encoding IFs in man that are expressed according to the 29 cell's specific requirements (1, 2). 30Despite differences in their amino acid sequence, all cytoskeletal IF proteins share their sec-31 ondary structure with a tripartite alpha-helical rod and disordered head and tail domains (3, 4). 32During the hierarchical assembly, two monomers form a parallel coiled coil and these dimers 33 organise into anti-parallel tetramers in a half-staggered arrangement. The tetramers assemble 34 laterally to form unit length filaments (ULFs), which in turn elongate to filaments by end-to-end 35 annealing (3). The resulting biopolymer comprises a complex high-order arrangement of coiled 36 coils (3), which allows IFs to be extended up to at least 4.5-fold their initial length (5-7). This 37 enormous extensibility is in stark contrast to microtubules and F-actin (8). 38Vimentin is the IF typically expressed in mesenchymal cells (2) and up-regulated during the 39 epithelial-to-mesenchymal transition in wound healing, early embryogenesis, and cancer meta-40 stasis (9). In addition to being highly extensible (7, 10, 11) vimentin is flexible (12-14) and 41 stable (15). During stretching, three regimes are observed in the force-strain data (7, 10, 11, 16, 42 17): an initial linear, elastic increase, a plateau of relatively constant force...

show abstract

“…Single intermediate filaments when pushed perpendicular to the long axis 49 , stretched along the long axis 50,51 or dragged on a surface 52 were able to withstand nN forces and the FE curves showed low and high force regimes. Previous MD simulations of stretching lamins in an orthogonal meshwork 32 (Supplementary Fig.…”

Section: In Situ Mechanics Of Lamin Filamentsmentioning

confidence: 99%

Nonlinear mechanics of lamin filaments and the meshwork topology build an emergent nuclear lamina

Sapra

Qin

Dubrovsky-Gaupp

et al. 2019

Preprint

View full text Add to dashboard Cite

The nuclear laminaa meshwork of intermediate filaments termed laminsfunctions as a mechanotransduction interface between the extracellular matrix and the nucleus via the cytoskeleton. Although lamins are primarily responsible for the mechanical stability of the nucleus in multicellular organisms, in situ characterization of lamin filaments under tension has remained elusive. Here, we apply an integrative approach combining atomic force microscopy, cryoelectron tomography, network analysis, and molecular dynamics simulations to directly measure the mechanical response of single lamin filaments in its threedimensional meshwork. Endogenous lamin filaments portray non-Hookean behaviorthey deform reversibly under a force of a few hundred picoNewtons and stiffen at nanoNewton forces. The filaments are extensible, strong and tough, similar to natural silk and superior to the synthetic polymer Kevlar ® . Graph theory analysis shows that the lamin meshwork is not a random arrangement of filaments but the meshwork topology follows 'small world' properties. Our results suggest that the lamin filaments arrange to form a robust, emergent meshwork that dictates the mechanical properties of individual lamin filaments. The combined approach provides quantitative insights into the structure-function organization of lamins in situ, and implies a role of meshwork topology in laminopathies.

show abstract

Nonlinear Loading-Rate-Dependent Force Response of Individual Vimentin Intermediate Filaments to Applied Strain

Cited by 95 publications

References 38 publications

Vimentin intermediate filaments undergo irreversible conformational changes during cyclic loading

Vimentin intermediate filaments undergo irreversible conformational changes during cyclic loading

Tuning Intermediate Filament Mechanics by Variation of pH and Ion Charges

Nonlinear mechanics of lamin filaments and the meshwork topology build an emergent nuclear lamina

Contact Info

Product

Resources

About