Promotes neurite outgrowth in hippocampal neurons. Enhances the cell surface expression of 2 NMDA receptor subunits GRIN1 and GRIN2A. May play a role in redistributing DLG4 to the cell periphery (By similarity). Forms heteromeric complexes with LRFN1, LRFN3, LRFN4 and LRFN5. Can form homomeric complexes, but not across cell junctions. Interacts with 2 NMDA receptor subunits GRIN1 and GRIN2A. Interacts with DLG1, DLG2, DLG3 and DLG4 (By similarity). The PDZ-binding motif is required for cell surface expression, neurite outgrowth promotion and interaction with DLG1, DLG3 and DLG4. Glycosylated. Belongs to the LRFN family.