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) (By similarity). Interacts with CRB2 (via intracellular domain) (By similarity). Interacts with CRB3 (via intracellular domain) (By similarity). Expressed in the outer limiting membrane, retinal pigment epithelium, outer nuclear layer and outer plexiform layer of the retina (at protein level).