Ionotropic glutamate receptor, metazoa (IPR001508)

Short name: Iono_rcpt_met

Overlapping homologous superfamilies


Family relationships



Ionotropic glutamate receptors (iGluRs) are a highly conserved family of ligand-gated ion channels present in animals, plants, and bacteria, which are best characterised for their roles in synaptic communication in vertebrate nervous systems [PMID: 14977400]. A variant subfamily of iGluRs, the Ionotropic Receptors (IRs), consist of non-glutamate-binding chemosensory receptors first identified in Drosophila melanogaster. They function in detecting odors and tastants [PMID: 20808886].

There are three classes of ionotropic glutamate receptors (iGluRs): kainate receptors, alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptors and N-methyl D-aspartate (NMDA) receptors. The NMDA receptor is highly permeable to calcium ions and plays a key role in the plasticity of synapses, which is believed to underlie memory and learning, as well as the development of the nervous system. Abnormal activation has been suggested to lead to neuronal cell death observed in many acute and chronic disorders such as ischemia, stroke, Alzheimer's disease, and Huntington's disease [PMID: 1532151].

NMDA receptors possess 4 transmembrane (TM) helical domains in the C-terminal half of the sequence and require both glycine and glutamate for activation, resulting in influx of calcium ions into the cell [PMID: 1532151]. The receptors can also be activated by polyamine, they can be blocked by magnesium ions, inhibited by zinc ions, and modulated by arachidonic acid. Other non-NMDA glutamate receptors (e.g., kainate) are structurally similar to NMDA receptors, but are functionally distinct, possibly as a result of amino acid substitutions at important positions in the sequence.

GO terms

Biological Process

GO:0006811 ion transport

Molecular Function

GO:0005216 ion channel activity
GO:0038023 signaling receptor activity

Cellular Component

GO:0016020 membrane

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.