The glutamate receptor 1, a homo- or heterotetramer is an ionotropic glutamate receptor. L-glutamate acts as an excitatory neurotransmitter at many synapses in the central nervous system. Binding of the excitatory neurotransmitter L-glutamate induces a conformation change, leading to the opening of the cation channel, and thereby converts the chemical signal to an electrical impulse. The glutamate receptor then desensitizes rapidly and enters a transient inactive state, characterized by the presence of bound agonist. Phosphorylation of Ser831 has been linked to synaptic plasticity as well s learning and memory.