Polyunsaturated fatty acids differentially modulate membrane elasticity in membranes containing high cholesterol

Membrane composition is important for the function of membrane proteins including ion channels and membrane-embedded receptors. One class of proteins that are especially sensitive to membrane composition are mechanosensitive channels, which activate in response to changes in membrane tension. Recently, polyunsaturated fatty acids (PUFAs) were demonstrated to alter mechanosensitive channel behavior, but the mechanism for these observations remains unknown. Mechanosensitive channel behavior is expected to be dependent on membrane mechanical properties such as the membrane area expansion modulus (Ka), which measures the extent to which membrane tension exerts a change in bilayer area.