Afadin- and ?-actinin-binding protein ADIP directly binds ??-COP, a subunit of the coatomer complex

Afadin DIL domain-interacting protein (ADIP) is a novel protein that binds both afadin and α-actinin and localizes at adherens junctions, which are formed by nectins and cadherins, cell–cell adhesion molecules. Afadin is an actin filament (F-actin)-binding protein which connects nectins to the actin cytoskeleton. α-Actinin is another F-actin-binding protein that is indirectly associated with cadherins through the catenin complex. ADIP is at least partly involved in the physical association of nectins and cadherins. We show here that ADIP furthermore binds β′-COP, a subunit of the coatomer complex. ADIP co-localizes with β′-COP at the Golgi complex in Madin Darby canine kidney and normal rat kidney cells. These results suggest that ADIP is involved in vesicle trafficking from the Golgi to the endoplasmic reticulum and through the Golgi complex by interacting with the coatomer complex.