Structure of Ternary Biomembranes

Biological membranes are not a simple homogeneous layer of proteins and lipids, but rather are organized into discrete regions that can be characterized by distinct lipid and protein content. These membrane microdomains which have been named “lipid rafts, are mainly composed of sphingolipids packed together with sterols and play an important role in cellular function. Rafts are thought to be surrounded by a more fluid liquid-disordered phase constituted of unsaturated phospholipids. Similar microdomains exist in plant plasma membrane enriched in sphingolipids and a mixture of plant sterols. We are interested in understanding the properties of domains formed in ternary mixtures, composed of saturated and unsaturated lipids together with plant sterols, which could resemble raft formation in real plant cells.