In studies of PSD95, Professor Seth Grant's group showed that memories are formed when neurotransmitter receptors associate with proteins.
PSD95 is a protein that binds to the inside surface of neurotransmitter receptors, and when we mutated that protein in mice, we found that the animals had impaired learning, but the receptor still acted normally. This established that neurotransmitter receptors act through the proteins associated with them to lay down the memory trace. It’s not just about the receptor, it’s about the proteins associated with it.
Post-synaptic density 95 protein (PSD95), also known as synapse-associated protein 90 (SAP90) or A0013, is a scaffold protein that belongs to the membrane-associated guanylate kinase (MAGUK) family (PSD93, PSD95, SAP97, SAP102).
Post-synaptic density protein 93 (PSD93), also known as channel-associated protein of synapse-110 (Chapsyn-110) or A0014, is a scaffold protein that belongs to the membrane-associated guanylate kinase (MAGUK) family (PSD93, PSD95, SAP97, SAP102).