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Updated: May 18, 2026
08:44
Visualizing Actin and Microtubule Coupling Dynamics In Vitro by Total Internal Reflection Fluorescence (TIRF) Microscopy
Published on: July 20, 2022
Tau protein diffuses along the microtubule lattice
Maike H Hinrichs1, Avesta Jalal, Bernhard Brenner
1Institute for Molecular and Cell Physiology, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625 Hannover, Germany.
The Journal of Biological Chemistry
|September 29, 2012
Summary
Tau protein diffuses along microtubules, independent of motor proteins. This 1D microtubule lattice diffusion aids Tau distribution, potentially compensating for compromised active transport.
Area of Science:
- Cell Biology
- Neuroscience
- Biophysics
Background:
- Current models propose motor protein-dependent transport or cytoplasmic diffusion for Tau protein.
- Tau is generally considered stationary when bound to microtubules.
Purpose of the Study:
- To investigate the potential for Tau protein diffusion along microtubules.
- To explore an alternative mechanism for Tau intracellular distribution.
Main Methods:
- Single-molecule total internal reflection fluorescence microscopy was employed.
- Individual fluorescently labeled Tau molecules were tracked along microtubules.
Main Results:
- Approximately 50% of detected Tau molecules exhibited bidirectional movement along microtubules.
- Tau diffusion along microtubules was sensitive to ionic strength, pH, and tubulin C-termini.
- Diffusion parameters were independent of Tau concentration.
Conclusions:
- One-dimensional diffusion of Tau along the microtubule lattice is a viable mechanism for Tau distribution.
- This diffusion can guide Tau to microtubule ends, independent of motor proteins.
- This pathway may be crucial when active transport is impaired.
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