Plays a role in cell-cell adhesion and neuron guidance via its interactions with FLRT2 and FLRT3 that are expressed at the surface of adjacent cells. Plays a role in the development of glutamatergic synapses in the cortex. Important in determining the connectivity rates between the principal neurons in the cortex. Interacts (via olfactomedin-like domain) with FLRT3 (via extracellular domain); the interaction is direct (PubMed:22405201). Identified in a complex with FLRT3 and UNC5B; does not interact with UNC5B by itself. Identified in a complex with FLRT3 and UNC5D; does not interact with UNC5D by itself (By similarity). Interacts (via olfactomedin-like domain) with FLRT1 (via extracellular domain). Interacts (via olfactomedin-like domain) with FLRT2 (via extracellular domain). Interacts (via extracellular domain) with TENM1. Interacts (via extracellular domain) with TENM3 (By similarity). Predominantly expressed in brain, followed by heart, placenta, pancreas, kidney and testis. The Olfactomedin-like domain is required for the synapse-promoting function and the interaction with FLRT3. The Olfactomedin-like and the SUEL-type lectin domains are required for the interaction with TENM1 (By similarity). Proteolytically cleaved into 2 subunits, an extracellular subunit and a seven-transmembrane subunit. O-glycosylated (major) and N-glycosylated. Belongs to the G-protein coupled receptor 2 family. LN-TM7 subfamily.