GNAT3 Antibody – Rabbit Polyclonal

G-alpha t3: Guanine nucleotide-binding protein (G protein) alpha subunit playing a prominent role in bitter and sweet taste transduction as well as in umami (monosodium glutamate, monopotassium glutamate, and inosine monophosphate) taste transduction. Transduction by this alpha subunit involves coupling of specific cell-surface receptors with a cGMP-phosphodiesterase; Activation of phosphodiesterase lowers intracellular levels of cAMP and cGMP which may open a cyclic nucleotide-suppressible cation channel leading to influx of calcium, ultimately leading to release of neurotransmitter. Indeed, denatonium and strychnine induce transient reduction in cAMP and cGMP in taste tissue, whereas this decrease is inhibited by GNAT3 antibody. Gustducin heterotrimer transduces response to bitter and sweet compounds via regulation of phosphodiesterase for alpha subunit, as well as via activation of phospholipase C for beta and gamma subunits, with ultimate increase inositol trisphosphate and increase of intracellular Calcium. GNAT3 can functionally couple to taste receptors to transmit intracellular signal: receptor heterodimer TAS1R2/TAS1R3 senses sweetness and TAS1R1/TAS1R3 transduces umami taste, whereas the T2R family GPCRs act as bitter sensors. Functions also as lumenal sugar sensors in the gut to control the expression of the Na+-glucose transporter SGLT1 in response to dietaty sugar, as well as the secretion of Glucagon-like peptide- 1, GLP-1 and glucose-dependent insulinotropic polypeptide, GIP. Thus, may modulate the gut capacity to absorb sugars, with implications in malabsorption syndromes and diet-related disorders including diabetes and obesity. Belongs to the G-alpha family. G(i/o/t/z) subfamily.

Protein type: G protein, heterotrimeric; G protein; G protein, heterotrimeric alpha G((i/o/t/z))

Chromosomal Location of Human Ortholog: 7q21.11

Cellular Component: protein complex; photoreceptor inner segment; photoreceptor outer segment; apical plasma membrane; plasma membrane; acrosome; heterotrimeric G-protein complex; axoneme

Molecular Function: GTPase activity; G-protein-coupled receptor binding; GTP binding; metal ion binding; G-protein beta/gamma-subunit binding; G-protein coupled photoreceptor activity

Biological Process: G-protein signaling, coupled to cAMP nucleotide second messenger; response to nicotine; platelet activation; synaptic transmission; sensory perception of umami taste; sensory perception of sweet taste; metabolic process; detection of chemical stimulus involved in sensory perception of bitter taste; G-protein signaling, adenylate cyclase inhibiting pathway; blood coagulation; detection of visible light