LIPID MICRODOMAINS AND MEMBRANE TRAFFICKING IN MAMMALIAN-CELLS

This overview summarizes the data for how epithelial cells sort and de liver proteins and lipids to the apical and basolateral cell surface d omains. The basolateral pathway uses a Rab-SNARE mechanism for docking and fusion, while the apical route employs a different machinery. Thi s latter mechanism is based on lipid microdomains, composed of cluster s of sphingolipids and cholesterol, which function as rafts for apical delivery. The sphingolipid-cholesterol raft mechanism seems to be emp loyed generally by mammalian cells to transport raft-associated protei ns to their post-Golgi destinations.