Transit of receptors for epidermal growth factor and transferrin through clathrin-coated pits. Analysis of the kinetics of receptor entry.

摘要: Selective enrichment of clathrin-coated membranes by anticlathrin immunoadsorption was used to examine the internalization receptor-ligand complexes through coated pits. Using Staphylococcus aureus-anticlathrin antibody and [35S]methionine-labeled KB cells, kinetics association epidermal growth factor (EGF-R) transferrin receptors (TF-R) with were directly examined. The accumulation EGF-R in pits at cell surface dependent upon EGF binding. then passed sequentially a compartment which did not react second compartment. degraded lysosomes half-life approximately 41-55 min. tumor promoter, 4 beta-phorbol 12-myristate 13-acetate, appears mimic action inducing receptor internalization. In contrast results EGF-R, TF-R found presence or absence TF, concentration significantly change time. method presented should be great utility for examining biochemical changes that occur during receptor-mediated endocytosis sorting ligands receptors.