“…Basolateral sorting is guided by basolateral sorting signals (Keller and Simons, 1997;Rodriguez-Boulan et al, 2005), and they include: short tyrosine motifs such as Yxxf or NPXY (Brewer and Roth, 1991;Le Bivic et al, 1991;Matter et al, 1992), dileucine (Hunziker and Fumey, 1994) or monoleucine motifs with nearby acidic patches (Deora et al, 2004), PxxP, found in EGFR and pleomorphic motifs that do not yet fall into established classes, found in NCAM (Le Gall et al, 1994), transferrin receptor (Odorizzi and Trowbridge, 1997) and polymeric IgA receptor (Aroeti and Mostov, 1994) ( Figure 2). Yeast 2 and 3 hybrid assays (Ohno et al, 1995;Janvier et al, 2003) demonstrated that Yxxf motifs interact with the m subunit of AP adaptors (AP1, AP2, AP3, AP4), whereas dileucine motifs of the type [DE]XXXL [LI] bind to g and s1 subunits of AP1 and to d and s3 subunits of AP3 (Kirchhausen, 2000;Bonifacino and Traub, 2003).…”