A mechanical model of fold formation on the plasma membrane

Abstract

A model of plasma membrane folding formation under the action of longitudinal and transverse mechanical forces applied to it is presented. These forces arise due to changes in protein-lipid and lipid-lipid interactions in the membrane and the submembrane spectrin-actin-ankyrin network under changing external conditions (temperature, pH), and interaction with ligands. A model of a linear elastic continuum is used. It is established that the amplitude of the height of folds is directly proportional to the amplitude of the applied distributed transverse forces and inversely proportional to the longitudinal stress. It is shown that if the value of the longitudinal stress exceeds a certain critical value, then the membrane folds are modulated by subfolds. The distributed transverse force has the same wavelength as the membrane folds. The results of mo-deling at a qualitative level explain the results of atomic force microscopy of the surface of erythrocyte membranes during their interaction with stress hormones and androgens.