TAS1R3: Difference between revisions

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{{Infobox_gene}}
{{PBB_Controls
'''Taste receptor type 1 member 3''' is a [[protein]] that in humans is encoded by the ''TAS1R3'' [[gene]].<ref name="pmid11319557">{{cite journal | vauthors = Montmayeur JP, Liberles SD, Matsunami H, Buck LB | title = A candidate taste receptor gene near a sweet taste locus | journal = Nat Neurosci | volume = 4 | issue = 5 | pages = 492–8 | date = Apr 2001 | pmid = 11319557 | pmc =  | doi = 10.1038/87440 }}</ref><ref name="entrez">{{cite web | title = Entrez Gene: TAS1R3 taste receptor, type 1, member 3| url = https://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=83756| accessdate = }}</ref> The ''TAS1R3'' gene encodes the human homolog of mouse Sac [[taste receptor]], a major determinant of differences between sweet-sensitive and -insensitive mouse strains in their responsiveness to sucrose, saccharin, and other sweeteners.<ref name="entrez" /><ref>{{Cite journal|last=Bachmanov|first=Alexander A.|last2=Li|first2=Xia|last3=Reed|first3=Danielle R.|last4=Ohmen|first4=Jeffery D.|last5=Li|first5=Shanru|last6=Chen|first6=Zhenyu|last7=Tordoff|first7=Michael G.|last8=de Jong|first8=Pieter J.|last9=Wu|first9=Chenyan|date=2001|title=Positional cloning of the mouse saccharin preference (Sac) locus|journal=Chemical senses|volume=26|issue=7|pages=925–933|issn=0379-864X|pmc=3644801|pmid=11555487|via=}}</ref>
| update_page = yes
| require_manual_inspection = no
| update_protein_box = yes
| update_summary = yes
| update_citations = yes
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<!-- The GNF_Protein_box is automatically maintained by Protein Box Bot.  See Template:PBB_Controls to Stop updates. -->
== Structure ==
{{GNF_Protein_box
| image =
| image_source =
| PDB =  
| Name = Taste receptor, type 1, member 3
| HGNCid = 15661
| Symbol = TAS1R3
| AltSymbols =; T1R3
| OMIM = 605865
| ECnumber = 
| Homologene = 12890
| MGIid = 1933547
| Function = {{GNF_GO|id=GO:0004872 |text = receptor activity}} {{GNF_GO|id=GO:0008067 |text = metabotropic glutamate, GABA-B-like receptor activity}} {{GNF_GO|id=GO:0008527 |text = taste receptor activity}} {{GNF_GO|id=GO:0046982 |text = protein heterodimerization activity}}
| Component = {{GNF_GO|id=GO:0016020 |text = membrane}} {{GNF_GO|id=GO:0016021 |text = integral to membrane}}
| Process = {{GNF_GO|id=GO:0007165 |text = signal transduction}} {{GNF_GO|id=GO:0007186 |text = G-protein coupled receptor protein signaling pathway}} {{GNF_GO|id=GO:0050896 |text = response to stimulus}} {{GNF_GO|id=GO:0050916 |text = sensory perception of sweet taste}} {{GNF_GO|id=GO:0050917 |text = sensory perception of umami taste}}
| Orthologs = {{GNF_Ortholog_box
    | Hs_EntrezGene = 83756
    | Hs_Ensembl = ENSG00000169962
    | Hs_RefseqProtein = NP_689414
    | Hs_RefseqmRNA = NM_152228
    | Hs_GenLoc_db = 
    | Hs_GenLoc_chr = 1
    | Hs_GenLoc_start = 1256557
    | Hs_GenLoc_end = 1260549
    | Hs_Uniprot = Q7RTX0
    | Mm_EntrezGene = 83771
    | Mm_Ensembl = ENSMUSG00000029072
    | Mm_RefseqmRNA = NM_031872
    | Mm_RefseqProtein = NP_114078
    | Mm_GenLoc_db = 
    | Mm_GenLoc_chr = 4
    | Mm_GenLoc_start = 154703073
    | Mm_GenLoc_end = 154707162
    | Mm_Uniprot = Q925D8
  }}
}}
'''Taste receptor, type 1, member 3''', also known as '''TAS1R3''', is a human [[gene]].<ref name="entrez">{{cite web | title = Entrez Gene: TAS1R3 taste receptor, type 1, member 3| url = http://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=83756| accessdate = }}</ref>


<!-- The PBB_Summary template is automatically maintained by Protein Box Bot. See Template:PBB_Controls to Stop updates. -->
The protein encoded by the ''TAS1R3'' gene is a [[G protein-coupled receptor]] with seven trans-membrane domains and is a component of the heterodimeric [[amino acid]] [[taste receptor]] TAS1R1+3 and [[sweet]] [[taste receptor]] TAS1R2+3. This receptor is formed as a [[protein dimer]] with either [[TAS1R1]] or [[TAS1R2]].<ref name="Nelson2001">{{cite journal | vauthors = Nelson G, Hoon MA, Chandrashekar J, Zhang Y, Ryba NJ, Zuker CS | title = Mammalian sweet taste receptors | journal = Cell | volume = 106 | issue = 3 | pages = 381–390 | year = 2001 | pmid = 11509186 | doi = 10.1016/S0092-8674(01)00451-2 }}</ref>
{{PBB_Summary
Experiments have also shown that a homo-dimer of TAS1R3 is also sensitive to natural [[sugar]] substances. This has been hypothesized as the mechanism by which [[sugar substitute]]s do not have the same taste qualities as natural sugars.<ref name="Zhao">{{cite journal | vauthors = Zhao GQ, Zhang Y, Hoon MA, Chandrashekar J, Erlenbach I, Ryba NJ, Zuker CS | title = The receptors for mammalian sweet and umami taste | journal = Cell | volume = 115 | issue = 3 | pages = 255–266 | year = 2003 | pmid = 14636554 | doi = 10.1016/S0092-8674(03)00844-4 }}</ref>
| section_title =  
| summary_text = The TAS1R3 gene encodes the human homolog of mouse Sac, a major determinant of differences between sweet-sensitive and -insensitive mouse strains in their responsiveness to sucrose, saccharine, and other sweeteners.[supplied by OMIM]<ref name="entrez">{{cite web | title = Entrez Gene: TAS1R3 taste receptor, type 1, member 3| url = http://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=83756| accessdate = }}</ref>
}}


==See also==
== Ligands ==
 
The [[G protein-coupled receptors]] for sweet and umami taste are formed by dimers of the TAS1R proteins.
The TAS1R1+3 taste receptor is sensitive to the glutamate in MSG as well as the synergistic taste-enhancer molecules [[inosine monophosphate]] (IMP) and [[guanosine monophosphate]] (GMP).  These taste-enhancer molecules are unable to activate the receptor alone, but are rather used to enhance receptor responses many to L-amino acids.<ref name="Nelson2002">{{cite journal | vauthors = Nelson G, Chandrashekar J, Hoon MA, Feng L, Zhao G, Ryba NJ, Zuker CS | title = An amino-acid taste receptor | journal = Nature | volume = 416 | issue = 6877 | pages = 199–202 | year = 2002 | pmid = 11894099 | doi = 10.1038/nature726 }}</ref> The TAS1R2+3 receptor has been shown to respond to natural sugars [[sucrose]] and [[fructose]], and to artificial sweeteners [[saccharin]], [[acesulfame potassium]], [[dulcin]], [[guanidinoacetic acid]].<ref name="Nelson2001"/>
 
== Signal transduction ==
 
[[TAS1R2]] and [[TAS1R1]] receptors have been shown to bind to [[G protein]]s, most often the [[gustducin]] Gα subunit, although a gusducin knock-out has shown small residual activity. [[TAS1R2]] and [[TAS1R1]] have also been shown to activate Gαo and Gαi protein subunits.<ref name="”sainz”">{{cite journal | vauthors = Sainz E, Cavenagh MM, LopezJimenez ND, Gutierrez JC, Battey JF, Northup JK, Sullivan SL | title = The G-protein coupling properties of the human sweet and amino acid taste receptors | journal = Developmental Neurobiology | volume = 67 | issue = 7 | pages = 948–959 | year = 2007 | pmid = 17506496 | doi = 10.1002/dneu.20403 }}</ref> This suggests that TAS1R1 and [[TAS1R2]] are [[G protein-coupled receptors]] that inhibit [[adenylyl cyclase]]s to decrease [[cyclic guanosine monophosphate]] (cGMP) levels in [[taste receptor]]s.<ref name="Abaffy">{{cite journal | vauthors = Abaffy T, Trubey KR, Chaudhari N | title = Adenylyl cyclase expression and modulation of cAMP in rat taste cells | journal = American Journal of Physiology. Cell Physiology | volume = 284 | issue = 6 | pages = C1420–C1428 | year = 2003 | pmid = 12606315 | doi = 10.1152/ajpcell.00556.2002 }}</ref> The TAS1R3 protein, however, has been shown in vitro to couple with Gα subunits at a much lower rate than the other TAS1R proteins.  While the protein structures of the TAS1R proteins are similar, this experiment shows that the G protein-coupling properties of TAS1R3 may be less important in the transduction of taste signals than the [[TAS1R1]] and [[TAS1R2]] proteins.<ref name="”sainz”"/>
 
== Location and innervation ==
 
TAS1R1+3 expressing cells are found in [[fungiform papilla]]e at the tip and edges of the tongue and palate taste receptor cells in the roof of the mouth.<ref name="Nelson2001"/>  These cells are shown to synapse upon the [[chorda tympani]] nerves to send their signals to the brain.<ref name="Nelson2002"/> TAS1R2+3 expressing cells are found in [[circumvallate papilla]]e and [[foliate papilla]]e near the back of the tongue and palate taste receptor cells in the roof of the mouth.<ref name="Nelson2001"/>  These cells are shown to synapse upon the [[glossopharyngeal nerve]]s to send their signals to the brain.<ref name="Bachmanov">{{cite journal | vauthors = Beamis JF, Shapshay SM, Setzer S, Dumon JF | title = Teaching models for Nd:YAG laser bronchoscopy | journal = Chest | volume = 95 | issue = 6 | pages = 1316–1318 | year = 1989 | pmid = 2721271 | doi = 10.1378/chest.95.6.1316 }}</ref><ref name="Danilova">{{cite journal | vauthors = Danilova V, Hellekant G | title = Comparison of the responses of the chorda tympani and glossopharyngeal nerves to taste stimuli in C57BL/6J mice | journal = BMC Neuroscience | volume = 4 | pages = 5–6 | year = 2003 | pmid = 12617752 | pmc = 153500 | doi = 10.1186/1471-2202-4-5 }}</ref> TAS1R and TAS2R (bitter) channels are not expressed together in any taste buds.<ref name="Nelson2001"/>
 
== See also ==
* [[Taste receptor]]
* [[Taste receptor]]
* [[TAS1R1]]
* [[TAS1R2]]


==References==
== References ==
{{reflist|2}}
{{reflist|35em}}


==Further reading==
== Further reading ==
{{refbegin | 2}}
{{refbegin|35em}}
{{PBB_Further_reading
*{{cite journal | vauthors = Chandrashekar J, Hoon MA, Ryba NJ, Zuker CS | title = The receptors and cells for mammalian taste. | journal = Nature | volume = 444 | issue = 7117 | pages = 288–94 | year = 2007 | pmid = 17108952 | doi = 10.1038/nature05401 }}
| citations =
*{{cite journal | vauthors = Max M, Shanker YG, Huang L, Rong M, Liu Z, Campagne F, Weinstein H, Damak S, Margolskee RF | title = Tas1r3, encoding a new candidate taste receptor, is allelic to the sweet responsiveness locus Sac. | journal = Nat. Genet. | volume = 28 | issue = 1 | pages = 58–63 | year = 2001 | pmid = 11326277 | doi = 10.1038/88270 }}
*{{cite journal | author=Chandrashekar J, Hoon MA, Ryba NJ, Zuker CS |title=The receptors and cells for mammalian taste. |journal=Nature |volume=444 |issue= 7117 |pages= 288-94 |year= 2007 |pmid= 17108952 |doi= 10.1038/nature05401 }}
*{{cite journal | vauthors = Nelson G, Chandrashekar J, Hoon MA, Feng L, Zhao G, Ryba NJ, Zuker CS | title = An amino-acid taste receptor. | journal = Nature | volume = 416 | issue = 6877 | pages = 199–202 | year = 2002 | pmid = 11894099 | doi = 10.1038/nature726 }}
*{{cite journal | author=Montmayeur JP, Liberles SD, Matsunami H, Buck LB |title=A candidate taste receptor gene near a sweet taste locus. |journal=Nat. Neurosci. |volume=4 |issue= 5 |pages= 492-8 |year= 2001 |pmid= 11319557 |doi= 10.1038/87440 }}
*{{cite journal | vauthors = Li X, Staszewski L, Xu H, Durick K, Zoller M, Adler E | title = Human receptors for sweet and umami taste. | journal = Proc. Natl. Acad. Sci. U.S.A. | volume = 99 | issue = 7 | pages = 4692–6 | year = 2002 | pmid = 11917125 | pmc = 123709 | doi = 10.1073/pnas.072090199 }}
*{{cite journal  | author=Max M, Shanker YG, Huang L, ''et al.'' |title=Tas1r3, encoding a new candidate taste receptor, is allelic to the sweet responsiveness locus Sac. |journal=Nat. Genet. |volume=28 |issue= 1 |pages= 58-63 |year= 2001 |pmid= 11326277 |doi= 10.1038/88270 }}
*{{cite journal | vauthors = Spadaccini R, Trabucco F, Saviano G, Picone D, Crescenzi O, Tancredi T, Temussi PA | title = The mechanism of interaction of sweet proteins with the T1R2-T1R3 receptor: evidence from the solution structure of G16A-MNEI. | journal = J. Mol. Biol. | volume = 328 | issue = 3 | pages = 683–92 | year = 2003 | pmid = 12706725 | doi = 10.1016/S0022-2836(03)00346-2 }}
*{{cite journal | author=Nelson G, Chandrashekar J, Hoon MA, ''et al.'' |title=An amino-acid taste receptor. |journal=Nature |volume=416 |issue= 6877 |pages= 199-202 |year= 2002 |pmid= 11894099 |doi= 10.1038/nature726 }}
*{{cite journal | vauthors = Ariyasu T, Matsumoto S, Kyono F, Hanaya T, Arai S, Ikeda M, Kurimoto M | title = Taste receptor T1R3 is an essential molecule for the cellular recognition of the disaccharide trehalose. | journal = In Vitro Cell. Dev. Biol. Anim. | volume = 39 | issue = 1-2 | pages = 80–8 | year = 2004 | pmid = 12892531 | doi = 10.1290/1543-706X(2003)039<0080:TRTIAE>2.0.CO;2 }}
*{{cite journal | author=Li X, Staszewski L, Xu H, ''et al.'' |title=Human receptors for sweet and umami taste. |journal=Proc. Natl. Acad. Sci. U.S.A. |volume=99 |issue= 7 |pages= 4692-6 |year= 2002 |pmid= 11917125 |doi= 10.1073/pnas.072090199 }}
*{{cite journal | vauthors = Jiang P, Ji Q, Liu Z, Snyder LA, Benard LM, Margolskee RF, Max M | title = The cysteine-rich region of T1R3 determines responses to intensely sweet proteins. | journal = J. Biol. Chem. | volume = 279 | issue = 43 | pages = 45068–75 | year = 2004 | pmid = 15299024 | doi = 10.1074/jbc.M406779200 }}
*{{cite journal | author=Spadaccini R, Trabucco F, Saviano G, ''et al.'' |title=The mechanism of interaction of sweet proteins with the T1R2-T1R3 receptor: evidence from the solution structure of G16A-MNEI. |journal=J. Mol. Biol. |volume=328 |issue= 3 |pages= 683-92 |year= 2003 |pmid= 12706725 |doi= }}
*{{cite journal | vauthors = Xu H, Staszewski L, Tang H, Adler E, Zoller M, Li X | title = Different functional roles of T1R subunits in the heteromeric taste receptors. | journal = Proc. Natl. Acad. Sci. U.S.A. | volume = 101 | issue = 39 | pages = 14258–63 | year = 2005 | pmid = 15353592 | pmc = 521102 | doi = 10.1073/pnas.0404384101 }}
*{{cite journal | author=Ariyasu T, Matsumoto S, Kyono F, ''et al.'' |title=Taste receptor T1R3 is an essential molecule for the cellular recognition of the disaccharide trehalose. |journal=In Vitro Cell. Dev. Biol. Anim. |volume=39 |issue= 1-2 |pages= 80-8 |year= 2004 |pmid= 12892531 |doi= 10.1290/1543-706X(2003)039<0080:TRTIAE>2.0.CO;2 }}
*{{cite journal | author = Taniguchi K | title = Expression of the sweet receptor protein, T1R3, in the human liver and pancreas. | journal = J. Vet. Med. Sci. | volume = 66 | issue = 11 | pages = 1311–4 | year = 2005 | pmid = 15585941 | doi = 10.1292/jvms.66.1311 }}
*{{cite journal | author=Jiang P, Ji Q, Liu Z, ''et al.'' |title=The cysteine-rich region of T1R3 determines responses to intensely sweet proteins. |journal=J. Biol. Chem. |volume=279 |issue= 43 |pages= 45068-75 |year= 2004 |pmid= 15299024 |doi= 10.1074/jbc.M406779200 }}
*{{cite journal | vauthors = Jiang P, Cui M, Zhao B, Liu Z, Snyder LA, Benard LM, Osman R, Margolskee RF, Max M | title = Lactisole interacts with the transmembrane domains of human T1R3 to inhibit sweet taste. | journal = J. Biol. Chem. | volume = 280 | issue = 15 | pages = 15238–46 | year = 2005 | pmid = 15668251 | doi = 10.1074/jbc.M414287200 }}
*{{cite journal | author=Xu H, Staszewski L, Tang H, ''et al.'' |title=Different functional roles of T1R subunits in the heteromeric taste receptors. |journal=Proc. Natl. Acad. Sci. U.S.A. |volume=101 |issue= 39 |pages= 14258-63 |year= 2005 |pmid= 15353592 |doi= 10.1073/pnas.0404384101 }}
*{{cite journal | vauthors = Galindo-Cuspinera V, Winnig M, Bufe B, Meyerhof W, Breslin PA | title = A TAS1R receptor-based explanation of sweet 'water-taste'. | journal = Nature | volume = 441 | issue = 7091 | pages = 354–7 | year = 2006 | pmid = 16633339 | doi = 10.1038/nature04765 }}
*{{cite journal | author=Taniguchi K |title=Expression of the sweet receptor protein, T1R3, in the human liver and pancreas. |journal=J. Vet. Med. Sci. |volume=66 |issue= 11 |pages= 1311-4 |year= 2005 |pmid= 15585941 |doi= }}
*{{cite journal | vauthors = Behrens M, Bartelt J, Reichling C, Winnig M, Kuhn C, Meyerhof W | title = Members of RTP and REEP gene families influence functional bitter taste receptor expression. | journal = J. Biol. Chem. | volume = 281 | issue = 29 | pages = 20650–9 | year = 2006 | pmid = 16720576 | doi = 10.1074/jbc.M513637200 }}
*{{cite journal | author=Jiang P, Cui M, Zhao B, ''et al.'' |title=Lactisole interacts with the transmembrane domains of human T1R3 to inhibit sweet taste. |journal=J. Biol. Chem. |volume=280 |issue= 15 |pages= 15238-46 |year= 2005 |pmid= 15668251 |doi= 10.1074/jbc.M414287200 }}
*{{cite journal | vauthors = Koizumi A, Nakajima K, Asakura T, Morita Y, Ito K, Shmizu-Ibuka A, Misaka T, Abe K | title = Taste-modifying sweet protein, neoculin, is received at human T1R3 amino terminal domain. | journal = Biochem. Biophys. Res. Commun. | volume = 358 | issue = 2 | pages = 585–9 | year = 2007 | pmid = 17499612 | doi = 10.1016/j.bbrc.2007.04.171 }}
*{{cite journal | author=Galindo-Cuspinera V, Winnig M, Bufe B, ''et al.'' |title=A TAS1R receptor-based explanation of sweet 'water-taste'. |journal=Nature |volume=441 |issue= 7091 |pages= 354-7 |year= 2006 |pmid= 16633339 |doi= 10.1038/nature04765 }}
*{{cite journal |vauthors=Mosinger B, Redding KM, Parker MR, Yevshayeva V, Yee KK, Dyomina K, Li Y, Margolskee RF |title=Genetic loss or pharmacological blockade of testes-expressed taste genes causes male sterility |journal=Proceedings of the National Academy of Sciences of the United States of America |volume=110 |issue=30 |pages=12319–24 |year=2013 |pmid=23818598 |pmc=3725061 |doi=10.1073/pnas.1302827110 |bibcode=2013PNAS..11012319M }}
*{{cite journal | author=Gregory SG, Barlow KF, McLay KE, ''et al.'' |title=The DNA sequence and biological annotation of human chromosome 1. |journal=Nature |volume=441 |issue= 7091 |pages= 315-21 |year= 2006 |pmid= 16710414 |doi= 10.1038/nature04727 }}
*{{cite journal  | author=Behrens M, Bartelt J, Reichling C, ''et al.'' |title=Members of RTP and REEP gene families influence functional bitter taste receptor expression. |journal=J. Biol. Chem. |volume=281 |issue= 29 |pages= 20650-9 |year= 2006 |pmid= 16720576 |doi= 10.1074/jbc.M513637200 }}
*{{cite journal | author=Koizumi A, Nakajima K, Asakura T, ''et al.'' |title=Taste-modifying sweet protein, neoculin, is received at human T1R3 amino terminal domain. |journal=Biochem. Biophys. Res. Commun. |volume=358 |issue= 2 |pages= 585-9 |year= 2007 |pmid= 17499612 |doi= 10.1016/j.bbrc.2007.04.171 }}
}}
{{refend}}
{{refend}}


{{membrane-protein-stub}}
== External links ==
* [http://www.genecards.org/cgi-bin/carddisp.pl?gene=TAS1R3 TAS1R3 Gene]
* [http://omim.org/entry/605865 TASTE RECEPTOR TYPE 1, MEMBER 3; TAS1R3]
 
{{G protein-coupled receptors|g3}}
{{NLM content}}
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Revision as of 00:42, 9 November 2017

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Identifiers
Aliases
External IDsGeneCards: [1]
Orthologs
SpeciesHumanMouse
Entrez

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Ensembl

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UniProt

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RefSeq (mRNA)

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RefSeq (protein)

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Location (UCSC)n/an/a
PubMed searchn/an/a
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View/Edit Human

Taste receptor type 1 member 3 is a protein that in humans is encoded by the TAS1R3 gene.[1][2] The TAS1R3 gene encodes the human homolog of mouse Sac taste receptor, a major determinant of differences between sweet-sensitive and -insensitive mouse strains in their responsiveness to sucrose, saccharin, and other sweeteners.[2][3]

Structure

The protein encoded by the TAS1R3 gene is a G protein-coupled receptor with seven trans-membrane domains and is a component of the heterodimeric amino acid taste receptor TAS1R1+3 and sweet taste receptor TAS1R2+3. This receptor is formed as a protein dimer with either TAS1R1 or TAS1R2.[4] Experiments have also shown that a homo-dimer of TAS1R3 is also sensitive to natural sugar substances. This has been hypothesized as the mechanism by which sugar substitutes do not have the same taste qualities as natural sugars.[5]

Ligands

The G protein-coupled receptors for sweet and umami taste are formed by dimers of the TAS1R proteins. The TAS1R1+3 taste receptor is sensitive to the glutamate in MSG as well as the synergistic taste-enhancer molecules inosine monophosphate (IMP) and guanosine monophosphate (GMP). These taste-enhancer molecules are unable to activate the receptor alone, but are rather used to enhance receptor responses many to L-amino acids.[6] The TAS1R2+3 receptor has been shown to respond to natural sugars sucrose and fructose, and to artificial sweeteners saccharin, acesulfame potassium, dulcin, guanidinoacetic acid.[4]

Signal transduction

TAS1R2 and TAS1R1 receptors have been shown to bind to G proteins, most often the gustducin Gα subunit, although a gusducin knock-out has shown small residual activity. TAS1R2 and TAS1R1 have also been shown to activate Gαo and Gαi protein subunits.[7] This suggests that TAS1R1 and TAS1R2 are G protein-coupled receptors that inhibit adenylyl cyclases to decrease cyclic guanosine monophosphate (cGMP) levels in taste receptors.[8] The TAS1R3 protein, however, has been shown in vitro to couple with Gα subunits at a much lower rate than the other TAS1R proteins. While the protein structures of the TAS1R proteins are similar, this experiment shows that the G protein-coupling properties of TAS1R3 may be less important in the transduction of taste signals than the TAS1R1 and TAS1R2 proteins.[7]

Location and innervation

TAS1R1+3 expressing cells are found in fungiform papillae at the tip and edges of the tongue and palate taste receptor cells in the roof of the mouth.[4] These cells are shown to synapse upon the chorda tympani nerves to send their signals to the brain.[6] TAS1R2+3 expressing cells are found in circumvallate papillae and foliate papillae near the back of the tongue and palate taste receptor cells in the roof of the mouth.[4] These cells are shown to synapse upon the glossopharyngeal nerves to send their signals to the brain.[9][10] TAS1R and TAS2R (bitter) channels are not expressed together in any taste buds.[4]

See also

References

  1. ↑ Montmayeur JP, Liberles SD, Matsunami H, Buck LB (Apr 2001). "A candidate taste receptor gene near a sweet taste locus". Nat Neurosci. 4 (5): 492–8. doi:10.1038/87440. PMID 11319557.
  2. ↑ 2.0 2.1 "Entrez Gene: TAS1R3 taste receptor, type 1, member 3".
  3. ↑ Bachmanov, Alexander A.; Li, Xia; Reed, Danielle R.; Ohmen, Jeffery D.; Li, Shanru; Chen, Zhenyu; Tordoff, Michael G.; de Jong, Pieter J.; Wu, Chenyan (2001). "Positional cloning of the mouse saccharin preference (Sac) locus". Chemical senses. 26 (7): 925–933. ISSN 0379-864X. PMC 3644801. PMID 11555487.
  4. ↑ 4.0 4.1 4.2 4.3 4.4 Nelson G, Hoon MA, Chandrashekar J, Zhang Y, Ryba NJ, Zuker CS (2001). "Mammalian sweet taste receptors". Cell. 106 (3): 381–390. doi:10.1016/S0092-8674(01)00451-2. PMID 11509186.
  5. ↑ Zhao GQ, Zhang Y, Hoon MA, Chandrashekar J, Erlenbach I, Ryba NJ, Zuker CS (2003). "The receptors for mammalian sweet and umami taste". Cell. 115 (3): 255–266. doi:10.1016/S0092-8674(03)00844-4. PMID 14636554.
  6. ↑ 6.0 6.1 Nelson G, Chandrashekar J, Hoon MA, Feng L, Zhao G, Ryba NJ, Zuker CS (2002). "An amino-acid taste receptor". Nature. 416 (6877): 199–202. doi:10.1038/nature726. PMID 11894099.
  7. ↑ 7.0 7.1 Sainz E, Cavenagh MM, LopezJimenez ND, Gutierrez JC, Battey JF, Northup JK, Sullivan SL (2007). "The G-protein coupling properties of the human sweet and amino acid taste receptors". Developmental Neurobiology. 67 (7): 948–959. doi:10.1002/dneu.20403. PMID 17506496.
  8. ↑ Abaffy T, Trubey KR, Chaudhari N (2003). "Adenylyl cyclase expression and modulation of cAMP in rat taste cells". American Journal of Physiology. Cell Physiology. 284 (6): C1420–C1428. doi:10.1152/ajpcell.00556.2002. PMID 12606315.
  9. ↑ Beamis JF, Shapshay SM, Setzer S, Dumon JF (1989). "Teaching models for Nd:YAG laser bronchoscopy". Chest. 95 (6): 1316–1318. doi:10.1378/chest.95.6.1316. PMID 2721271.
  10. ↑ Danilova V, Hellekant G (2003). "Comparison of the responses of the chorda tympani and glossopharyngeal nerves to taste stimuli in C57BL/6J mice". BMC Neuroscience. 4: 5–6. doi:10.1186/1471-2202-4-5. PMC 153500. PMID 12617752.

Further reading

External links

This article incorporates text from the United States National Library of Medicine, which is in the public domain.

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