InterPro domain: IPR019594

This region, sometimes called the S1 domain, is the luminal domain just upstream of the first, M1, transmembrane region of transmembrane ion-channel proteins, and binds L-glutamate and glycine in the ionotropic glutamate receptor NMDA [ 1 , 2 ]. It is found in association with IPR001320 .

Ionotropic Receptors (IRs) are a variant subfamily of the Ionotropic glutamate receptors (iGluRs). In IRs, the ligand binding domain lacks one or more residues that directly contact the glutamate ligand in iGluRs [ 3 ].

1. Subunit- and site-specific pharmacology of the NMDA receptor channel. Prog. Neurobiol. 59, 279-98
2. Molecular characterization of the family of the N-methyl-D-aspartate receptor subunits. J. Biol. Chem. 268, 2836-43
3. Ancient protostome origin of chemosensory ionotropic glutamate receptors and the evolution of insect taste and olfaction. PLoS Genet. 6, e1001064