Vimentin intermediate filaments modulate cell traction force but not cell sensitivity to substrate stiffness

Area of Science:

• Cell Biology
• Biophysics
• Mechanobiology

Background:

• Cellular mechanical sensing (durosensing) is vital for tissue repair and development.
• The cytoskeleton, including intermediate filaments (IFs) like vimentin, mediates cell mechanics and matrix interaction.
• Vimentin's specific role in durosensing remains poorly understood.

Purpose of the Study:

• To investigate the function of vimentin in cellular mechanosensing of substrate stiffness.
• To determine if vimentin is essential for durosensitivity in fibroblasts.

Main Methods:

• Vimentin expression was reduced in 3T3 fibroblasts using shRNA.
• Cellular responses, including area and traction force, were measured across varying substrate stiffness.
• Durosensitivity was quantified by the rate of change in cell area and traction force with stiffness.

Main Results:

• Vimentin knockdown influenced traction force generation in response to substrate stiffness.
• Reducing vimentin levels did not significantly impair the overall durosensitivity of the cells.
• Cell area changes with substrate stiffness were not significantly affected by vimentin knockdown.

Conclusions:

• Vimentin contributes to modulating cell traction force during durosensing.
• Cells can effectively sense and respond to substrate stiffness even without significant vimentin expression.
• Vimentin may be a redundant component in the cellular machinery for substrate stiffness sensing.