Plays a role in protein sorting and trafficking between the trans-Golgi network (TGN) and endosomes. Mediates the ARF-dependent recruitment of clathrin to the TGN and binds ubiquitinated proteins and membrane cargo molecules with a cytosolic acidic cluster-dileucine (DXXLL) motif (PubMed:10747088). Mediates export of the GPCR receptor ADRA2B to the cell surface (PubMed:27901063). Regulates retrograde transport of phosphorylated form of BACE1 from endosomes to the trans-Golgi network (PubMed:15615712).