THE EMERGENCE OF CLATHRIN-INDEPENDENT PINOCYTIC PATHWAYS

Receptor-mediated endocytosis via clathrin-coated vesicles is by far t he best characterized example of pinocytosis. It has been suggested th at clathrin-coated vesicles mediate all pinocytosis in mammalian cells . This is still a matter of debate, however, and recent results provid e strong evidence for 'clathrin-independent' pinocytic pathways. The s elective regulation of these alternate endocytic pathways and the iden tification of receptors targeted to them provide new tools for the fun ctional and mechanistic characterization of clathrin-independent pinoc ytosis.