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Calcium Dependency and Contractility in TNT-Connected C2C12 Cells Responding to Mechanical Stimulation
Yanli Sun1,2, Hucheng Zhao2
1School of Mechanical Engineering, Xinjiang University, Urumqi, 830047 China.
Cellular and Molecular Bioengineering
|July 15, 2026
Summary
Tunneling nanotubes (TNTs) enable cell communication. Mechanical stimulation alters cell mechanics via calcium signaling and gap junctions, demonstrating TNTs
Area of Science:
- Cell Biology
- Biophysics
- Intercellular Communication
Background:
- Tunneling nanotubes (TNTs) are critical for long-range cell communication.
- Electrical responses via TNTs under mechanical stress are known, but their link to cellular mechanical changes is unclear.
Purpose of the Study:
- To investigate the relationship between TNT-mediated intercellular signaling and cellular mechanical behavior.
- To explore the roles of calcium signaling, ion channels, gap junctions, and contractility in this process.
Main Methods:
- Mechanical stimulation was applied to C2C12 cell pairs connected by TNTs.
- Traction force and cell spreading area were measured under various pharmacological interventions.
Main Results:
- Mechanical stimulation increased traction force and decreased cell spreading area in connected cells.
- These biomechanical changes were attenuated by calcium depletion, T-type calcium channel inhibition, and gap junction blockade.
- L-type calcium channel inhibition did not significantly impact the observed responses.
Conclusions:
- A calcium-dependent mechanism links TNT-mediated signaling to biomechanical regulation in connected cells.
- This study highlights the functional role of TNTs in coordinating cellular mechanics.
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