Phase dynamics and domain interactions in biological membranes

Every living organism involves biological membranes one way or another, which are important in most biological processes and cellular functions. All of these are dramatically manipulated by not only the sizes and numbers of domains (lipid rafts) but also their lateral organization and phase dynamics in biomembranes. In this article, we discuss the recent findings on domain formation and phase transition behaviors in phospholipid mixtures containing cholesterol and relate to membrane lateral heterogeneity. Thermodynamic forces and considerations regulating in-plane as well as out-of-plane domain structures and interactions in lipid monolayers and bilayers are described. Compositional symmetry and asymmetry between inner and outer leaflets in biomembranes are also considered.