Rafts:: a simple way to control apoptosis by subcellular redistribution

Apoptosis is an essential feature of development and homeostasis in higher organisms. Lipid rafts are subdomains of the plasma membrane that contain high concentrations of cholesterol and sphingolipids. In response to intra or extracellular stimuli, lipid rafts can include or exclude proteins to variable extents. This favors specific protein-protein interactions and modulates the activity of signaling cascades. Recently, a number of proteins involved in apoptotic signals have been located in lipid rafts. Among these proteins is included Bad, a pro-apoptotic molecule belonging to the Bcl-2 family. Bad is attached to lipid rafts in proliferating cells while associated to mitochondria in apoptotic cells, suggesting that the interaction of Bad with rafts is a dynamic process involved in the control of apoptosis. In this review, we briefly summarize the structure of rafts and illustrate their contribution to the control of apoptosis. (C) 2003 Editions scientifiques et medicales Elsevier SAS. All rights reserved.