PSD-95 is a molecular scaffolding protein that binds and clusters NMDA receptors at neuronal synapses. PSD-95 is involved in the guanine nucleotide-mediated signal transduction pathway. This gene encodes a member of the membrane-associated guanylate kinase (MAGUK) family. PSD-95 heteromultimerizes with DLG2 and together they are recruited into the same NMDA receptor and potassium channel clusters. They may interact at postsynaptic sites to form a multimeric scaffold for the clustering of receptors, ion channels, and associated signaling proteins.