Fusion between vesicles from the pathway of receptor‐mediated endocytosis in a cell‐free system

Abstract
Fusion between endocytic vesicles containing 125I‐transferrin and ones containing anti‐transferrin antibody was monitored by the formation of an immune complex. Fusion required ATP and only occurred between specific populations of vesicles. Cytosol was also required. Trypsinisation of the preparations or pre‐treatment with N‐ethylmaleimide abolished the fusion reaction.