Seems to be a constitutive component of clathrin-coated pits that is required for receptor-mediated endocytosis. Involved in endocytosis of integrin beta-1 (ITGB1) and transferrin receptor (TFR); internalization of ITGB1 as DAB2-dependent cargo but not TFR seems to require association with DAB2. Interacts with EPS15, AGFG1/HRB and AGFG2/HRBL. Associates with the clathrin-associated adapter protein complex 2 (AP-2) (By similarity). Interacts with FCHO1. Interacts with FCHO2. Interacts (via EH domains) with DAB2. Interacts with UBQLN1 (via ubiquitin-like domain). Interacts with CAVIN3 (via leucine-zipper domain) (PubMed:19262564). Interacts with REPS2 (PubMed:10393179). Localized to plasma membrane coated pits. Phosphorylated on tyrosine residues by EGFR. Studies in clathrin-mediated endocytosis used a siRNA mixture of EPS15 and EPS15L1.