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Updated: Mar 19, 2026
08:02
Using Microfluidics and Fluorescence Microscopy to Study the Assembly Dynamics of Single Actin Filaments and Bundles
Published on: May 5, 2022
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Profilin connects actin assembly with microtubule dynamics
Michaela Nejedla1, Sara Sadi1, Vadym Sulimenko2
1Department of Molecular Biosciences, Wenner-Gren Institute, Stockholm University, SE-106 91 Stockholm, Sweden.
Molecular Biology of the Cell
|June 17, 2016
Summary
Profilin, a protein controlling actin assembly, also dynamically associates with microtubules. This dual role suggests profilin regulates both actin dynamics and microtubule turnover.
Area of Science:
- Cell Biology
- Cytoskeletal Dynamics
Background:
- Profilin controls actin nucleation and assembly in eukaryotic cells.
- Actin nucleation and elongation promoting factors (NEPFs) recruit profilin:actin for filament formation.
- Microtubules are involved in cell polarity, migration, and focal adhesion turnover, indicating crosstalk with actin.
Purpose of the Study:
- To investigate the functional link between profilin and microtubules.
- To identify the role of formins as mediators in this association.
- To understand profilin's contribution to cytoskeletal dynamics.
Main Methods:
- Utilized fluorescence microscopy, including superresolution microscopy.
- Employed siRNA to modulate profilin expression.
- Applied drug treatments to disrupt actin dynamics.
Main Results:
- Demonstrated a functional link between profilin and microtubules, mediated by formins.
- Showed that profilin dynamically associates with microtubules.
- Found that this microtubule-associated profilin balances actin assembly and influences microtubule dynamics.
Conclusions:
- Profilin is functionally linked to microtubules, with formins as key mediators.
- Profilin dynamically associates with microtubules, impacting actin assembly and microtubule turnover.
- Profilin acts as a regulator of microtubule (+)-end turnover, in addition to its role in actin control.
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