Gq alpha subunit

protein
Name = guanine nucleotide binding protein (G protein), q polypeptide
caption =


width =
HGNCid = 4390
Symbol = GNAQ
AltSymbols =
EntrezGene = 2776
OMIM = 600998
RefSeq = NM_002072
UniProt = P50148
PDB =
ECnumber =
Chromosome = 9
Arm = q
Band = 21
LocusSupplementaryData =protein
Name = guanine nucleotide binding protein (G protein), alpha 11 (Gq class)
caption =


width =
HGNCid = 4379
Symbol = GNA11
AltSymbols =
EntrezGene = 2767
OMIM = 139313
RefSeq = NM_002067
UniProt = P29992
PDB =
ECnumber =
Chromosome = 19
Arm = p
Band = 13.3
LocusSupplementaryData =protein
Name = guanine nucleotide binding protein (G protein), alpha 14
caption =


width =
HGNCid = 4382
Symbol = GNA14
AltSymbols =
EntrezGene = 9630
OMIM = 604397
RefSeq = NM_004297
UniProt = O95837
PDB =
ECnumber =
Chromosome = 9
Arm = q
Band = 21
LocusSupplementaryData =protein
Name = guanine nucleotide binding protein (G protein), alpha 15 (Gq class)
caption =


width =
HGNCid = 4383
Symbol = GNA15
AltSymbols =
EntrezGene = 2769
OMIM = 139314
RefSeq = NM_002068
UniProt = P30679
PDB =
ECnumber =
Chromosome = 19
Arm = p
Band = 13.3
LocusSupplementaryData =

G_q protein or G_q/11 is a heterotrimeric G protein subunit that activates phospholipase C (PLC). PLC in turn hydrolyzes phosphatidylinositol (PIP₂) to diacyl glycerol (DAG) and inositol triphosphate (IP₃) signal transduction pathway. DAG acts as a second messenger that activates Protein Kinase C (PKC) and IP₃ helps in phosphorylation of some proteins.

Function

G_q proteins are class of G proteins which work to activate phospholipase C (PLC), participating in a varity of cellular signaling pathways, including taste, manic depression, tumor promotion, etc.cite book | author = Alberts B, Lewis J, Raff M, Roberts K, Walter P| title = Molecular biology of the cell | publisher = Garland Science | location = New York | edition = 4^th Edition | year = 2002 | pages = | isbn = 0-8153-3218-1 | oclc = | doi = ]

The G_q protein works by activating PLC. PLC then cleaves a phospholipid. In the process, phosphatidylinositol 4,5-bisphosphate (PIP2) is cleaved into diacyl glycerol (DAG) and inositol 1,4,5-triphosphate (IP₃). DAG remains on bound to the membrane, and IP₃ is released as a soluble structure into the cytosol. IP₃ then diffuses through the cytosol to bind to IP₃ receptors, particular calcium channels in the endoplasmic reticulum (ER). These channels are specific to calcium and only allow the passage of calcium to move through. This causes the cytosolic concentration of Calcium to increase, causing a cascade of intracellular changes and activity.

: "Further reading:Calcium function in vertebrates"

In addition, calcium and DAG together works to activate PKC, which goes on to phosphorylate other things, leading to altered cellular activity.

: "Further reading:function of protein kinase C"

Examples of GPCR partners

From modulatory neurotransmitter receptors (amine receptors belonging to rhodopsin family), G_q is usually coupled to e.g. the G-protein coupled receptors:

* Alpha 1 adrenergic receptors
* 5-HT receptor type 2
* Muscarinic receptors 1, 3 and 5
* Histamine receptor type 1
* Calcitonin receptor

Genes

* GNAQ, gene|GNA11, gene|GNA14, gene|GNA15

See also

* Second messenger system

References

External links

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