May play a role in retinal photoreceptors development. Interacts with MPDZ (By similarity). May interact with GRIA2. Forms a complex with CRB1 and PALS1. Interacts with FASLG (By similarity). Localized at photoreceptor synaptic terminals in retina. Highly expressed in brain and detected in lung, and bone (at protein level). Also expressed in intestine and spleen. Belongs to the MAGUK family.