GRM6

L-glutamate is the major excitatory neurotransmitter in the central nervous system and activates both ionotropic and metabotropic glutamate receptors. Glutamatergic neurotransmission is involved in most aspects of normal brain function and can be perturbed in many neuropathologic conditions. The metabotropic glutamate receptors are a family of G protein-coupled receptors, that have been divided into 3 groups on the basis of sequence homology, putative signal transduction mechanisms, and pharmacologic properties. Group I includes GRM1 and GRM5 and these receptors have been shown to activate phospholipase C. Group II includes GRM2 and GRM3 while Group III includes GRM4, GRM6, GRM7 and GRM8. Group II and III receptors are linked to the inhibition of the cyclic AMP cascade but differ in their agonist selectivities. [provided by RefSeq]

Full Name

glutamate receptor, metabotropic 6

Function

G-protein coupled receptor for glutamate. Ligand binding causes a conformation change that triggers signaling via guanine nucleotide-binding proteins (G proteins) and modulates the activity of down-stream effectors, such as adenylate cyclase. Signaling inhibits adenylate cyclase activity (By similarity).

Signaling stimulates TRPM1 channel activity and Ca2+ uptake. Required for normal vision.

Biological Process

Chemical synaptic transmission Source: Ensembl
Detection of light stimulus involved in visual perception Source: UniProtKB
Detection of visible light Source: ProtInc
G protein-coupled glutamate receptor signaling pathway Source: UniProtKB
Locomotory behavior Source: Ensembl
Positive regulation of calcium ion import Source: UniProtKB
Regulation of synaptic transmission, glutamatergic Source: GO_Central
Retina development in camera-type eye Source: Ensembl

Cellular Location

Endoplasmic reticulum membrane; Golgi apparatus membrane; Cell membrane; Dendrite. Subject to trafficking from the endoplasmic reticulum to the Golgi apparatus and then to the cell membrane.

Involvement in disease

Night blindness, congenital stationary, 1B (CSNB1B):
A non-progressive retinal disorder characterized by impaired night vision. Congenital stationary night blindness type 1B is an autosomal recessive form associated with a negative electroretinogram waveform. Patients are night blind from an early age, and when maximally dark-adapted, they could perceive lights only with an intensity equal to or slightly dimmer than that normally detected by the cone system. ERGs in response to single brief flashes of light have clearly detectable a-waves, which are derived from photoreceptors, and greatly reduced b-waves, which are derived from the second-order inner retinal neurons. ERGs in response to sawtooth flickering light indicate a markedly reduced on response and a nearly normal OFF response. There is no subjective delay in the perception of suddenly appearing white vs black objects on a gray background.

Topology

Extracellular: 25-585
Helical: 586-608
Cytoplasmic: 609-622
Helical: 623-643
Extracellular: 644-654
Helical: 655-673
Cytoplasmic: 674-697
Helical: 698-718
Extracellular: 719-748
Helical: 749-770
Cytoplasmic: 771-783
Helical: 784-806
Extracellular: 807-819
Helical: 820-845
Cytoplasmic: 846-877