Measurements and Implications of How Electrical Potentials Can Bend Membranes

Lipid bilayer membranes are liquid crystals. The oppositely oriented head group dipoles in the lipid head groups makes the bilayer leaflets respond differently to applied electrical potential. While the density of dipoles decreases in one leaflet, it increases in the other leaflet upon application of a transmembrane electrical potential, thus resulting in bending of the bilayer. We investigated this flexoelectric phenomenon using coarse grained molecular dynamics simulations and show that increasing potentials bend the membrane to a larger extent. We demonstrate the implications of the phenomenon in the tubulation of giant unilamellar vesicles upon application of a calcium flux.