GNAT2

Guanine nucleotide binding protein (G protein), alpha transducing activity polypeptide 2
Identifiers
Symbols	GNAT2 ; ACHM4; GNATC
External IDs	OMIM: 139340 MGI: 95779 HomoloGene: 21092 GeneCards: GNAT2 Gene
Gene ontology Molecular function • G-protein coupled receptor binding • GTPase activity • signal transducer activity • GTP binding • G-protein coupled photoreceptor activity • G-protein beta/gamma-subunit complex binding • metal ion binding Cellular component • photoreceptor outer segment • photoreceptor inner segment • cytosol • heterotrimeric G-protein complex • plasma membrane • photoreceptor outer segment membrane Biological process • detection of chemical stimulus involved in sensory perception of bitter taste • G-protein coupled receptor signaling pathway • adenylate cyclase-modulating G-protein coupled receptor signaling pathway • positive regulation of cytosolic calcium ion concentration • visual perception • phototransduction • metabolic process • response to light intensity • retinal cone cell development • detection of light stimulus involved in visual perception Sources: Amigo / QuickGO
RNA expression pattern
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	2780	14686
Ensembl	ENSG00000134183	ENSMUSG00000009108
UniProt	P19087	P50149
RefSeq (mRNA)	NM_005272	NM_008141
RefSeq (protein)	NP_005263	NP_032167
Location (UCSC)	Chr 1: 109.6 – 109.62 Mb	Chr 3: 108.09 – 108.1 Mb
PubMed search

Guanine nucleotide-binding protein G(t) subunit alpha-2 is a protein that in humans is encoded by the GNAT2 gene.^[1][2]

Function

Transducin is a 3-subunit guanine nucleotide-binding protein (G protein) which stimulates the coupling of rhodopsin and cGMP-phoshodiesterase during visual impulses. The transducin alpha subunits in rods and cones are encoded by separate genes. This gene encodes the alpha subunit in cones.^[2]

References

1. Morris TA, Fong SL (Oct 1993). "Characterization of the gene encoding human cone transducin alpha-subunit (GNAT2)". Genomics 17 (2): 442–8. doi:10.1006/geno.1993.1345. PMID 8406495.
2. "Entrez Gene: GNAT2 guanine nucleotide binding protein (G protein), alpha transducing activity polypeptide 2".

Further reading

• Wilkie TM, Gilbert DJ, Olsen AS; et al. (1993). "Evolution of the mammalian G protein alpha subunit multigene family". Nat. Genet. 1 (2): 85–91. doi:10.1038/ng0592-85. PMID 1302014.
• Arshavsky VYu , Gray-Keller MP, Bownds MD (1991). "cGMP suppresses GTPase activity of a portion of transducin equimolar to phosphodiesterase in frog rod outer segments. Light-induced cGMP decreases as a putative feedback mechanism of the photoresponse". J. Biol. Chem. 266 (28): 18530–7. PMID 1655754.
• Mazzoni MR, Malinski JA, Hamm HE (1991). "Structural analysis of rod GTP-binding protein, Gt. Limited proteolytic digestion pattern of Gt with four proteases defines monoclonal antibody epitope". J. Biol. Chem. 266 (21): 14072–81. PMID 1713215.
• Fawzi AB, Fay DS, Murphy EA; et al. (1991). "Rhodopsin and the retinal G-protein distinguish among G-protein beta gamma subunit forms". J. Biol. Chem. 266 (19): 12194–200. PMID 1905716.
• Kubo M, Hirano T, Kakinuma M (1991). "Molecular cloning and sequence analysis of cDNA and genomic DNA for the human cone transducin alpha subunit". FEBS Lett. 291 (2): 245–8. doi:10.1016/0014-5793(91)81294-I. PMID 1936270.
• Lerea CL, Bunt-Milam AH, Hurley JB (1990). "Alpha transducin is present in blue-, green-, and red-sensitive cone photoreceptors in the human retina". Neuron 3 (3): 367–76. doi:10.1016/0896-6273(89)90261-4. PMID 2534964.
• Blatt C, Eversole-Cire P, Cohn VH; et al. (1988). "Chromosomal localization of genes encoding guanine nucleotide-binding protein subunits in mouse and human". Proc. Natl. Acad. Sci. U.S.A. 85 (20): 7642–6. doi:10.1073/pnas.85.20.7642. PMC 282248. PMID 2902634.
• Buss JE, Mumby SM, Casey PJ; et al. (1987). "Myristoylated alpha subunits of guanine nucleotide-binding regulatory proteins". Proc. Natl. Acad. Sci. U.S.A. 84 (21): 7493–7. doi:10.1073/pnas.84.21.7493. PMC 299322. PMID 3118369.
• Hirano T (1994). "[Analysis of cell specific transcription of the human cone transducin alpha subunit gene]". Hokkaido Igaku Zasshi 68 (6): 885–93. PMID 8112713.
• Morris TA, Fong WB, Ward MJ; et al. (1997). "Localization of upstream silencer elements involved in the expression of cone transducin alpha-subunit (GNAT2)". Invest. Ophthalmol. Vis. Sci. 38 (1): 196–206. PMID 9008644.
• Kohl S, Baumann B, Rosenberg T; et al. (2002). "Mutations in the cone photoreceptor G-protein alpha-subunit gene GNAT2 in patients with achromatopsia". Am. J. Hum. Genet. 71 (2): 422–5. doi:10.1086/341835. PMC 379175. PMID 12077706.
• Aligianis IA, Forshew T, Johnson S; et al. (2002). "Mapping of a novel locus for achromatopsia (ACHM4) to 1p and identification of a germline mutation in the alpha subunit of cone transducin (GNAT2)". J. Med. Genet. 39 (9): 656–60. doi:10.1136/jmg.39.9.656. PMC 1735242. PMID 12205108.
• Strausberg RL, Feingold EA, Grouse LH; et al. (2003). "Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences". Proc. Natl. Acad. Sci. U.S.A. 99 (26): 16899–903. doi:10.1073/pnas.242603899. PMC 139241. PMID 12477932.
• Piña AL, Baumert U, Loyer M, Koenekoop RK (2004). "A three base pair deletion encoding the amino acid (lysine-270) in the alpha-cone transducin gene". Mol. Vis. 10: 265–71. PMID 15094710.
• Gerhard DS, Wagner L, Feingold EA; et al. (2004). "The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)". Genome Res. 14 (10B): 2121–7. doi:10.1101/gr.2596504. PMC 528928. PMID 15489334.
• Rosenberg T, Baumann B, Kohl S; et al. (2005). "Variant phenotypes of incomplete achromatopsia in two cousins with GNAT2 gene mutations". Invest. Ophthalmol. Vis. Sci. 45 (12): 4256–62. doi:10.1167/iovs.04-0317. PMID 15557429.

External links

• GeneReviews/NIH/NCBI/UW entry on Achromatopsia
• OMIM entries on Achromatopsia