Description: Glutamate receptors are the predominant excitatory neurotransmitter receptors in the mammalian brain and are activated in a variety of normal neurophysiologic processes. These receptors are heteromeric protein complexes with multiple subunits, each possessing transmembrane regions, and all arranged to form a ligand-gated ion channel. The classification of glutamate receptors is based on their activation by different pharmacologic agonists. The GRIA1 belongs to a family of alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) receptors. Each of the members (GRIA1-4) include fip and flop isoforms generated by alternative RNA splicing resulting in a difference of 9 amino acids. The receptor subunits encoded by each isoform vary in their signal transduction properties. The isoform presented here is the flip isoform. AMPA-sensitive channels become impermeable to calcium by editing of mRNA in the coding region of the second transmembrane domain of glutamate receptor subunit. It involves a change of the base A in genomic DNA to the base G in mRNA. The GRIA2 subunit mRNA is completely edited in human brain.