Plays a role in the formation and organization of tight junctions during the establishment of polarity in epithelial cells. Component of a complex composed of PALS1, CRB1 and EPB41L5 (By similarity). Within the complex, interacts (via FERM domain) with PALS1 (via HOOK domain) and with CRB1 (via intracellular domain) (PubMed:17920587). Interacts with CRB2 (via intracellular domain) (By similarity). Interacts with CRB3 (via intracellular domain) (By similarity). Expressed in the retina (at protein level).