Cholesterol domains regulate the actin cytoskeleton at the leading edge of moving cells

The plasma membrane must be rigid to form a barrier between the cell interior and the extracellular milieu, while remaining sufficiently flexible to enable rapid changes in cell shape. The concept of the plasma membrane as a mosaic of microdomains can help to understand this combination of properties. A recent report shows that the polarization of cholesterol-enriched domains changes the viscoelastic properties of the membrane at the front of moving cells, permitting efficient formation of the actin network required to push the leading-edge membrane forward.