Related Experiment Video
Updated: May 23, 2025
08:28
Measurement of Force-Sensitive Protein Dynamics in Living Cells Using a Combination of Fluorescent Techniques
Published on: November 2, 2018
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Actin crosslinking is required for force sensing at tricellular junctions
Nilay Taneja1, Michael F Moubarak1, Meriel J McGovern1
1HHMI and Developmental Biology Program, Sloan Kettering Institute.
Biorxiv : the Preprint Server for Biology
|March 10, 2025
Summary
Fimbrin protein stabilizes epithelial cell adhesion under mechanical stress by reinforcing actin networks. Its absence disrupts force-response pathways, compromising tissue integrity during remodeling.
Area of Science:
- Cell Biology
- Biophysics
- Developmental Biology
Background:
- Mechanical forces are crucial for tissue development (morphogenesis).
- Epithelial adherens junctions manage these forces via actin cytoskeleton connections.
- The in vivo response of junctional actin networks to force remains unclear.
Purpose of the Study:
- To investigate the role of the actin crosslinker Fimbrin in epithelial force response.
- To understand how Fimbrin influences actomyosin contractility and cell adhesion under tension.
Main Methods:
- In vivo studies of epithelial tissues under mechanical tension.
- Analysis of Fimbrin recruitment to tricellular junctions.
- Assessment of actomyosin contractility and myosin-II activity.
- Evaluation of junction-stabilizing protein recruitment.
Main Results:
- Fimbrin is recruited to tricellular junctions under tension.
- Fimbrin amplifies actomyosin contractility and stabilizes cell adhesion.
- Loss of Fimbrin impairs actin reorganization and myosin-II activity under force.
- Fimbrin deficiency disrupts the recruitment of junction-stabilizing proteins, leading to adhesion failure.
- Increased Fimbrin activity aberrantly stabilizes adhesion by activating force-response pathways.
Conclusions:
- Fimbrin-mediated actin crosslinking is vital for modulating actomyosin dynamics during epithelial remodeling.
- Fimbrin reinforces cell adhesion under mechanical tension.
- Fimbrin acts as a key regulator of force-response pathways in epithelial tissues.
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