[A possible physico-chemical mechanism of cell fusion in skeletal muscle myogenesis by means of intercellular pinocytosis].

The fusion mechanism of cells in myogenesis of skeletal muscle is proposed on the basis of capacity of forming intercellular contacts with pentalamellar structure to invaginate up to the formation of free vesicles, i.e. the intercellular pinocytosis. This process leads to a "loss" of the membrane material with the following perforation and rupture of the membrane at the site of cell contact. The formation of invaginations is connected with the clusterization of proteins on the cytoplasmic surface of plasmalemma, accompanied by an alteration of Gibbs' surface energy with the appearance of chemically induced and bending moments. The transition from the invagination to the vesicle depending on osmotic gradient of pressure between the fusing cells was estimated quantitatively. This gradient is determined by the mechanism of polymerization of protein subunits during the assembly of contractile elements in one of fusing cells.