Gq alpha subunit

Gq alpha subunit

guanine nucleotide binding protein (G protein), q polypeptide
Identifiers
Symbol GNAQ
Entrez HUGO OMIM RefSeq UniProt Locus q21
guanine nucleotide binding protein (G protein), alpha 11 (Gq class)
Identifiers
Symbol GNA11
Entrez HUGO OMIM RefSeq UniProt Locus p13.3
guanine nucleotide binding protein (G protein), alpha 14
Identifiers
Symbol GNA14
Entrez HUGO OMIM RefSeq UniProt Locus q21
guanine nucleotide binding protein (G protein), alpha 15 (Gq class)
Identifiers
Symbol GNA15
Entrez HUGO OMIM RefSeq UniProt Locus p13.3

Gq protein or Gq/11 is a heterotrimeric G protein subunit that activates phospholipase C (PLC). PLC in turn hydrolyzes Phosphatidylinositol 4,5-bisphosphate (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

Gq proteins are class of G proteins which work to activate phospholipase C (PLC), participating in a variety of cellular signaling pathways.[1]

The Gq 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 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.[1]

Further reading: Calcium function in vertebrates

In addition, calcium and DAG together works to activate PKC, which goes on to phosphorylate other molecules, leading to altered cellular activity.[1]

Further reading: function of protein kinase C

Examples of GPCR partners

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

Genes

  • GNA15

See also

References

External links

  • Medical Subject Headings (MeSH)