Cell volume change through water efflux impacts cell stiffness and stem cell fate

Cells alter their mechanical properties in response to their local microenvironment; this plays a role in determining cell function and can even influence stem cell fate. Here, we identify a robust and unified relationship between cell stiffness and cell volume. As a cell spreads on a substrate, its volume decreases, while its stiffness concomitantly increases. We find that both cortical and cytoplasmic cell stiffness scale with volume for numerous perturbations, including varying substrate stiffness, cell spread area, and external osmotic pressure. The reduction of cell volume is a result of water efflux, which leads to a corresponding increase in intracellular molecular crowding. Furthermore, we find that…

• NS
  National Science Foundation

  Awards: DMR-1420570, DMR-1310266
• NI
  National Institutes of Health

  Awards: P01HL120839, HL86655, P01GM096971