Clathrin-mediated and caveolar endocytic pathways represent the major routes through which G protein-coupled receptors (GPCRs) could be internalized. GPCR kinase 2 (GRK2) and beta-arrestins are representative proteins that mediate the GPCR endocytosis. However, the molecular mechanisms through which GRK2 and beta-arrestin mediate clathrin-mediated and caveolar endocytosis remain unclear. In this study, we determined the cellular components and processes that mediate the selective interaction between clathrin/caveolinl and GRK2/beta-arrestins. For this we utilized the following: (i) mutant dopamine D-2 receptor and 132 adrenoceptor in which the potential GRK2 phosphorylation sites were altered and (ii) cells in which clathrin, caveolinl, beta-arrestins, or Mdm2 expression were knocked down. Our results showed that clathrin-mediated endocytosis occurs more rapidly than caveolar endocytosis. Clathrin-mediated endocytosis and the interaction between clathrin and GRK2/beta-arresting occurred in a GRK2-mediated receptor phosphorylation-dependent manner. In contrast, caveolar endocytosis and the interaction between caveolinl and GRK2/beta-arresting were independent of receptor phosphorylation status. Mdm2-mediated ubiquitination of beta-arrestin, which occurred in a receptor phosphorylationdependent manner, was required for the interaction of arrestin with clathrin. Thus, this study shows that GRK2-mediated receptor phosphorylation accompanied by beta-arrestin ubiquitination is a critical cellular event that links GRK2 and beta-arrestins to clathrin-mediated endocytosis. (C) 2020 Elsevier Inc. All rights reserved.