G-protein coupled receptor activated by glutamate that regulates axon outgrowth through the MAPK-cAMP-PKA signaling pathway during neuronal development (By similarity). Ligand binding causes a conformation change that triggers signaling via guanine nucleotide-binding proteins (G proteins) and modulates the activity of downstream effectors, such as adenylate cyclase that it inhibits. Homodimer (By similarity). Interacts with PICK1. Widely distributed throughout the brain. Belongs to the G-protein coupled receptor 3 family.