Computational investigation for deformation of lipid membrane by BAR proteins due to electrostatic interaction

Abstract

Deformation of lipid membrane by peripheral BAR (Bin/Amphiphysin/RVs) proteins due to electrostatic interaction between them has an important implication in field of cell-biological systems. We study the deformation behavior of a lipid membrane sheet subjected to electrostatic traction with the help of a very simple finite element elastic model. The lipid membrane is considered as an elastic sheet subjected to the electrostatic traction derived from the literature for the interaction between the lipid membrane and a single BAR protein. Both the small and large deformation behavior of the lipid membrane is considered. To predict small or infinitesimal deformation of the membrane, we use Hooke’s law and large deformation is predicted by Neo-Hookean strain energy density function. The small deformation behavior obtained from the present finite element model does not support the scaffolding mechanism of a single BAR protein binding with the lipid membrane. However, the large deformation behavior of the membrane predicts very well the scaffolding mechanism for the wide range of BAR proteins involved in cell-biological systems. The present model can be used for understanding deformation of any kind of elastic sheet driven by electrostatic forces.