Delta Glutamate Receptor (GluD1, GluD2)
The δ1 glutamate receptor (GluRδ1; GluD1) and the δ2 glutamate receptor (GluRδ2; GluD2) were cloned by homology screening in 1993 at the end of the “gold rush” for cloning of ionotropic glutamate receptor (iGluR) cDNA. They were regarded as orphan receptors for a long time since their endogenous ligands were unknown. GluD1 is highly expressed in hair cells of the auditory and vestibular systems in adult mice. Indeed, deletion of a gene encoding GluD1 (grid1) in mice leads to deficit in high-frequency hearing. In contrast, GluD2 is highly expressed in cerebellar Purkinje cells and deletion of a gene encoding GluD2 (grid2) results in cerebellar ataxia and characteristic phenotypes at parallel fiber (PF)–Purkinje cell synapses. Functionally, long-term depression (LTD) of synaptic transmission, which is thought to underlie motor coordination and motor learning, is completely blunted. Morphologically, approximately 40% of...
- Yuzaki M. Delta receptors. In: Gereau RW, Swanson GT, editors. The glutamate receptors. Totowa: Humana; 2008.Google Scholar