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Force Spectroscopy of Single Protein Molecules Using an Atomic Force Microscope
Published on: February 28, 2019
Exploring the mechanical properties of single vimentin intermediate filaments by atomic force microscopy
1Institut de Physique de la Matière Complexe, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland. camilo.guzman@epfl.ch
Journal of Molecular Biology
|June 13, 2006
Summary
Single vimentin intermediate filaments (IFs) provide mechanical stability to cells. Their bending modulus, measured using atomic force microscopy, suggests subunit sliding affects mechanical properties.
Area of Science:
- Biophysics
- Cell Biology
- Materials Science
Background:
- Intermediate filaments (IFs) are key cytoskeletal components providing mechanical stability.
- Vimentin IFs are crucial for cellular structural integrity under mechanical stress.
Purpose of the Study:
- To investigate the bending properties of single vimentin intermediate filaments.
- To determine the bending modulus and Young's modulus of vimentin IFs.
Main Methods:
- Atomic force microscopy (AFM) was used to elastically deform single vimentin IFs.
- Filaments were deformed while hanging over a porous membrane.
- Measurements were performed on both non-stabilized and glutaraldehyde-stabilized IFs.
Main Results:
- The bending modulus of non-stabilized vimentin IFs was measured to be between 300 MPa and 400 MPa.
- Stabilized IFs showed a two to three times increase in bending modulus.
- Results suggest axial sliding between vimentin subunits influences filament mechanics.
Conclusions:
- Vimentin IFs exhibit length-dependent bending modulus due to subunit sliding.
- The Young's modulus of vimentin IFs is estimated to be around 900 MPa or higher.
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