ROLE OF THE CYTOSKELETON IN ENDOCYTOSIS OF THE YEAST MALTOSE TRANSPORTER

Certain components of the cytoskeleton play a role in yeast fluid-phas e endocytosis as well as in endocytosis of the alpha-factor when this pheromone is bound to its 7-transmembrane segment receptor. The yeast maltose transporter is a 12-transmembrane segment protein that, under certain physiological conditions, is degraded in the vacuole after int ernalization by endocytosis. In this work, the possible role of the cy toskeleton in endocytosis of this transporter has been investigated. U sing mutants defective in beta-tubulin, actin and the actin-binding pr oteins Sac6 and Abp85, as well as nocodazole, which inhibits formation of microtubules, we have shown that actin microfilaments are involved in endocytosis of the maltose transporter whereas microtubules are no t. (C) 1997 by John Wiley & Sons, Ltd.