The ligand-binding domain of non-NMDA (N-methyl-D-aspartate) type ionotropic glutamate receptors, a member of the type 2 periplasmic-binding fold protein superfamily.
This subfamily represents the ligand-binding domain of non-NMDA (N-methyl-D-aspartate) type ionotropic glutamate receptors including AMPA (alpha-amino-3-hydroxyl-5-methyl-4-isoxazolepropionic acid) receptors (GluR1-4), kainate receptors (GluR5-7 and KA1/2), and orphan receptors delta 1/2. iGluRs form tetrameric ligand-gated ion channels, which are concentrated at postsynaptic sites in excitatory synapses where they fulfill a variety of different functions. While this ligand-binding domain of iGluRs is structurally homologous to the periplasmic binding fold type II superfamily, the N-terminal leucine/isoleucine/valine#binding protein (LIVBP)-like domain belongs to the periplasmic-binding fold type I.
Jiyao W et al.(2023). "The conserved domain database in 2023.",