Investigation of structure of the membrane rafts by means of computer modeling

Understanding the structure of the biological membrane and its role in the cell has evolved significantly since the introduction of the classical fluid mosaic model by Singer and Nicholson. Later fluid mosaic model has been redesigned, expanded and has become considerably complicated. It has been experimentally proved that the membrane consists of so-called rafts, which are functional “islands” with the specific lipid composition with proteins. Lipid rafts play a central role in many cellular processes, including barrier functions, membrane polarization and the cell signaling. Several groups of pathogens, bacteria, prions, viruses, parasites use lipid rafts for their purposes. Rafts always occur on both sides of the membrane opposite to each other, but the nature of the two-layer rafts are still poorly understood. Previously it was theoretically calculated that the shift of the monolayers in raft occurs, which reduces the mechanical energy of the boundaries, and ultimately leads to a bilayer structure of the raft. In this study with the help of computer modeling we study the energy of interaction between two monolayers of the raft in order to test the hypothesis about their relative shift.