A structural constituent of postsynaptic density. Involved in several processes, including axo-dendritic protein transport; clustering of voltage-gated potassium channels; and neurotransmitter receptor localization to postsynaptic specialization membrane. Acts upstream of or within chemical synaptic transmission and sensory perception of pain. Located in several cellular components, including main axon; postsynaptic density; and synaptic vesicle membrane. Is active in glutamatergic synapse. Is expressed in jaw bone; nervous system; and retina. Orthologous to human DLG2 (discs large MAGUK scaffold protein 2). [provided by Alliance of Genome Resources, Apr 2022]