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Updated: Aug 6, 2026
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A Protocol for Using Förster Resonance Energy Transfer (FRET)-force Biosensors to Measure Mechanical Forces across the Nuclear LINC Complex
Published on: April 11, 2017
The actin crosslinker Fimbrin is required for force sensing at tricellular junctions
Nilay Taneja1, Claire A Looney1, Michael F Moubarak1
1Howard Hughes Medical Institute and Developmental Biology Program, Sloan Kettering Institute, New York, NY, USA.
Developmental Cell
|July 24, 2026
Summary
Fimbrin protein is recruited to tricellular junctions by mechanical forces, enhancing cell adhesion and actin reorganization during epithelial remodeling. Its absence disrupts these processes, while its overactivity leads to aberrant adhesion.
Area of Science:
- Cell biology
- Biophysics
- Developmental biology
Background:
- Epithelial cells respond to mechanical forces via adherens junctions and the actin cytoskeleton.
- Tricellular junctions are critical for mechanotransduction, but their force response coordination during epithelial remodeling is unclear.
Purpose of the Study:
- To investigate the role of Fimbrin in coordinating force responses at tricellular junctions during epithelial remodeling.
- To understand how Fimbrin influences actin organization and cell adhesion under mechanical stress.
Main Methods:
- Utilized Drosophila models to study Fimbrin recruitment and function at tricellular junctions under force.
- Investigated the effects of Fimbrin absence and altered activity on actin dynamics and protein localization.
- Examined conserved mechanisms in mouse embryos, analyzing force-regulated actin remodeling and protein localization (Plastin3, Afadin).
Main Results:
- Fimbrin is recruited to tricellular junctions by mechanical forces, promoting actin reorganization and cell adhesion.
- Loss of Fimbrin impairs actin reorganization and junction stabilization under tension, leading to disrupted cell adhesion.
- Constitutive Fimbrin activity results in aberrant adhesion by over-activating force-response pathways.
- Fimbrin amplifies actomyosin contractility, directing force responses.
Conclusions:
- Fimbrin plays a conserved, crucial role in mechanotransduction at tricellular junctions in both Drosophila and mouse epithelia.
- Force-induced Fimbrin recruitment is essential for adaptive actin remodeling and maintaining cell adhesion during epithelial remodeling.
- Fimbrin acts as a key regulator of epithelial force responses by modulating actomyosin contractility and junction stability.
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