Plays a role in the formation of clathrin-coated invaginations and endocytosis. Binds EPS15 (By similarity). Interacts with ITSN1 (By similarity). Binds AP-2 and clathrin. Interacts with UBQLN2. In punctate structures throughout the cell, associated with clathrin-coated vesicles, and particularly concentrated in the region of the Golgi complex. Highest expression is found in brain. Detected at lower levels in lung and liver. The NPF repeat domain is involved in EPS15 binding. The DPW repeat domain is involved in AP-2 and clathrin binding. Ubiquitinated. Belongs to the epsin family. Extended N-terminus. Truncated C-terminus.