VPS26 moonlights as a -arrestin-like adapter for a 7-transmembrane RGS protein in Arabidopsis thaliana

Body of Abstract: Signals perceived by 7TM-receptors initiate removal of these receptors from the membrane. Agonist binding evokes phosphorylation of many 7TM receptors in animal cells to recruit β-arrestin, resulting in clathrin-mediated endocytosis (CME). Arrestins are not in plants, yet they have a well-characterized signal-induced CME of 7TM proteins (RGS1). We show that a component of the retromer complex, Vacuolar Protein Sorting-Associated 26, binds the phosphorylated C-terminal region of RGS1 as a VPS26A/B heterodimer and is required for downstream signaling.