| Identification |
|---|
| HMDB Protein ID
| CDBP02928 |
| Secondary Accession Numbers
| Not Available |
| Name
| Guanine nucleotide-binding protein G(t) subunit alpha-3 |
| Description
| Not Available |
| Synonyms
|
- Gustducin alpha-3 chain
|
| Gene Name
| GNAT3 |
| Protein Type
| Receptor |
| Biological Properties |
|---|
| General Function
| Involved in signal transducer activity |
| Specific Function
| 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 |
| GO Classification
|
| Function |
| purine nucleotide binding |
| binding |
| nucleotide binding |
| guanyl nucleotide binding |
| guanyl ribonucleotide binding |
| gtp binding |
| molecular transducer activity |
| signal transducer activity |
| Process |
| regulation of biological process |
| regulation of cellular process |
| signal transduction |
| signaling |
| signaling pathway |
| cell surface receptor linked signaling pathway |
| g-protein coupled receptor protein signaling pathway |
| biological regulation |
|
| Cellular Location
|
- Cytoplasm
|
| Pathways
|
Not Available
|
| Gene Properties |
|---|
| Chromosome Location
| Chromosome:7 |
| Locus
| 7q21.11 |
| SNPs
| GNAT3 |
| Gene Sequence
|
>1065 bp
ATGGGAAGTGGAATTAGTTCAGAGAGCAAGGAGTCAGCCAAAAGATCAAAAGAACTGGAG
AAAAAGCTTCAGGAGGATGCTGAGCGAGATGCAAGAACCGTAAAGCTGCTACTATTAGGA
GCAGGAGAATCTGGGAAAAGTACTATTGTTAAACAAATGAAGATCATCCATAAGAATGGT
TACAGTGAGCAAGAATGCATGGAGTTCAAAGCAGTAATTTACAGTAATACATTGCAATCC
ATCCTAGCTATTGTGAAAGCCATGACTACCCTTGGAATTGATTATGTAAATCCCAGAAGT
GCAGAGGACCAACGACAACTTTATGCAATGGCAAATACCCTGGAAGATGGTGGCATGACA
CCTCAACTGGCTGAGGTAATAAAACGGCTGTGGAGAGATCCAGGAATTCAGGCCTGCTTT
GAAAGGGCATCTGAATATCAGCTCAATGACTCAGCAGCTTACTACCTTAATGATTTAGAT
AGAATAACAGCATCTGGGTATGTGCCAAATGAACAAGATGTTCTCCATTCTCGAGTGAAA
ACGACTGGAATCATTGAAACTCAATTCTCCTTTAAAGACTTGCACTTCAGGATGTTTGAT
GTAGGTGGACAGAGATCTGAGAGAAAGAAGTGGATTCACTGCTTTGAAGGAGTTACATGC
ATTATATTTTGTGCTGCACTTAGTGCCTATGACATGGTCCTCGTGGAAGACGAAGAAGTG
AATAGAATGCATGAAAGCCTTCACCTGTTCAACAGTATCTGTAATCACAAGTATTTTTCA
ACAACCTCCATTGTCCTGTTCCTCAACAAAAAAGATATCTTTCAAGAAAAGGTAACCAAG
GTGCATCTTAGTATCTGCTTTCCAGAATACACTGGGCCAAATACATTTGAAGATGCAGGA
AACTACATCAAGAACCAGTTTCTAGACCTGAATTTAAAAAAAGAAGATAAGGAAATTTAT
TCCCACATGACCTGTGCTACTGACACCCAAAATGTCAAGTTTGTGTTTGACGCAGTTACA
GATATAATAATCAAAGAGAATCTAAAAGACTGTGGGCTTTTCTAA
|
| Protein Properties |
|---|
| Number of Residues
| 354 |
| Molecular Weight
| 40356.7 |
| Theoretical pI
| 5.87 |
| Pfam Domain Function
|
|
| Signals
|
|
|
Transmembrane Regions
|
|
| Protein Sequence
|
>Guanine nucleotide-binding protein G(t) subunit alpha-3
MGSGISSESKESAKRSKELEKKLQEDAERDARTVKLLLLGAGESGKSTIVKQMKIIHKNG
YSEQECMEFKAVIYSNTLQSILAIVKAMTTLGIDYVNPRSAEDQRQLYAMANTLEDGGMT
PQLAEVIKRLWRDPGIQACFERASEYQLNDSAAYYLNDLDRITASGYVPNEQDVLHSRVK
TTGIIETQFSFKDLHFRMFDVGGQRSERKKWIHCFEGVTCIIFCAALSAYDMVLVEDEEV
NRMHESLHLFNSICNHKYFSTTSIVLFLNKKDIFQEKVTKVHLSICFPEYTGPNTFEDAG
NYIKNQFLDLNLKKEDKEIYSHMTCATDTQNVKFVFDAVTDIIIKENLKDCGLF
|
| External Links |
|---|
| GenBank ID Protein
| 156139155 |
| UniProtKB/Swiss-Prot ID
| A8MTJ3 |
| UniProtKB/Swiss-Prot Entry Name
| GNAT3_HUMAN |
| PDB IDs
|
Not Available |
| GenBank Gene ID
| NM_001102386.1 |
| GeneCard ID
| GNAT3 |
| GenAtlas ID
| GNAT3 |
| HGNC ID
| HGNC:22800 |
| References |
|---|
| General References
| Not Available |