A role of membrane skeleton in discontinuous red blood cell shape transformations

A possible physical interpretation of a discontinuous transition between different red blood cell shapes is given. The red blood cell membrane is considered to consist of the bilayer part and the underlaying membrane skeleton. By taking into consideration that the stable cell shape corresponds to the minimum of the membrane energy, that consists of the bilayer and skeleton elastic energies and of the bilayer-skeleton interaction energy, it is shown that aggregation of the skeleton can cause the discontinuous cell shape transformation from a shape with the bilayer completely underlaid with the skeleton to the shape involving a spherical parent cell with completely underlaid bilayer and spherical daughter vesicles without the skeleton.