Sphingolipids in biomembranes

Sphingolipids are relatively minor components of cell membranes, but the last two decades have witnessed an increased interest in these molecules, and particularly the simplest of them ceramide and sphingosine, due to (a) their proposed role in cell signalling, and (b) their unusual biophysical properties. The latter include the tendency of ceramides to form non-lamellar structures, to permeabilize bilayers, and to promote transbilayer (flip-flop) motion of lipids. These properties were discovered in our lab. More recently we have characterized the interaction of ceramide and cholesterol, and the formation of gel-phase structures containing ceramide and cholesterol that could exist in cell membranes.