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Updated: Jun 28, 2025
09:33
High-Resolution Complexome Profiling by Cryoslicing BN-MS Analysis
Published on: October 15, 2019
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Vimentin filaments integrate low-complexity domains in a complex helical structure.
Matthias Eibauer1, Miriam S Weber2, Rafael Kronenberg-Tenga2
1Department of Biochemistry, University of Zurich, Zurich, Switzerland. m.eibauer@bioc.uzh.ch.
Nature Structural & Molecular Biology
|April 17, 2024
Summary
Researchers revealed the 3D structure of vimentin intermediate filaments (IFs), uncovering a unique helical assembly. This finding explains the remarkable mechanical strength and stretchability of these crucial cytoskeletal biopolymers.
Area of Science:
- Cell Biology
- Biophysics
- Structural Biology
Background:
- Intermediate filaments (IFs) are essential cytoskeletal components.
- They confer tissue-specific mechanical properties and participate in cellular processes.
- The 3D structure of IFs has been difficult to determine due to their complex architecture.
Purpose of the Study:
- To elucidate the three-dimensional structure of vimentin intermediate filaments (VIFs).
- To understand the structural basis for the mechanical properties of VIFs.
Main Methods:
- Cryo-focused ion-beam milling
- Cryo-electron microscopy
- Cryo-electron tomography
Main Results:
- Vimentin IFs assemble into a modular, intertwined, flexible helical structure.
- The cross-section reveals 40 α-helices organized into five protofibrils.
- Intrinsically disordered head domains form an internal fiber, while disordered tails create lateral connections.
Conclusions:
- The 3D structure of VIFs is a complex, modular helical assembly.
- Disordered protein domains play a critical role in VIFs' mechanical strength and stretchability.
- This study provides a structural basis for understanding IF biopolymer function.
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