Role of Clathrin-coated Vesicles in Glycoprotein Transport from the Cell Surface to the Golgi Complex

摘要: Plasma membrane glycoproteins recycle to the Golgi complex, but route followed by these proteins is not known. To elucidate pathway of transport, involvement clathrin-coated vesicles was tested. This accomplished comparing traffic wild type low density lipoprotein receptor (LDLR) and FH 683, a mutant whose endocytosis from cell surface in coated reduced 90-95%. Wild LDLR traveled sialyltransferase compartment with half-time 2.5 h K562 human leukemia cells expressing transfected cDNA. In contrast, 683 recycled at 33% rate, suggesting that largely transported involves vesicles. Moreover, because bud plasma are endosomes, surface-to-Golgi transport probably an endosomal intermediate. Finally, there substantial even though its greatly reduced, may be second traffic. Our results suggest move two routes. Two-thirds proceeds via vesicle-mediated while remainder follow clathrin-independent pathway.