GNAT3
Description
The GNAT3 (G protein subunit alpha transducin 3) is a protein-coding gene located on chromosome 7.
Guanine nucleotide-binding protein G(t) subunit alpha-3, also known as gustducin alpha-3 chain, is a protein subunit that in humans is encoded by the GNAT3 gene. Gustducin alpha-3 chain is a subunit of the heterotrimeric G protein gustducin that is responsible for basic taste.
GNAT3, also known as Gustducin alpha-3 chain, is a G protein alpha subunit involved in taste perception. It mediates bitter, sweet, and umami tastes. GNAT3 functions by coupling with cell surface receptors and activating phosphodiesterase, which lowers cAMP and cGMP levels, opening cation channels and causing calcium influx. This ultimately leads to neurotransmitter release. GNAT3 also activates phospholipase C, leading to increased inositol trisphosphate and intracellular calcium. GNAT3 interacts with taste receptors like TAS1R2/TAS1R3 for sweetness and TAS1R1/TAS1R3 for umami, and T2R family GPCRs for bitterness. GNAT3 also functions as a lumenal sugar sensor in the gut, controlling expression of the Na+-glucose transporter SGLT1 and secretion of GLP-1 and GIP. These functions may influence sugar absorption in the gut and play a role in malabsorption syndromes, diabetes, and obesity.
GNAT3 is also known as GDCA, HG1E.
