Plant clathrin-mediatedmembrane trafficking is involved in many developmental processes as well as in responses to environmental cues.Previous studies have shown that clathrin-mediated endocytosis of the plasma membrane (PM) auxin transporter PIN-FORMED 1 (PIN1) is regulated by the extracellular auxin receptor, AUXIN-BINDING PROTEIN 1 (ABP1).However, the mechanisms by which ABP1 and other factors regulate clathrin-mediated trafficking are poorly understood.