Summary: 7 transmembrane sweet-taste receptor of 3 GCPR
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Class C GPCR Edit Wikipedia article
- metabotropic glutamate receptors InterPro:Â IPR000162,
- GPCR, family 3, extracellular calcium-sensing receptor-related InterPro:Â IPR000068
- GPCR, family 3, metabotropic glutamate receptor
- GPCR, family 3, gamma-aminobutyric acid receptor, type B InterPro:Â IPR002455
- Bride of sevenless protein InterPro:Â IPR002956
- GPCR, family 3, vomeronasal receptor, type 2 InterPro:Â IPR004073
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7 transmembrane sweet-taste receptor of 3 GCPR Provide feedback
This is a domain of seven transmembrane regions that forms the C-terminus of some subclass 3 G-coupled-protein receptors. It is often associated with a downstream cysteine-rich linker domain, NCD3G PF07562 which is the human sweet-taste receptor, and the N-terminal domain, ANF_receptor PF01094. The seven TM regions assemble in such a way as to produce a docking pocket into which such molecules as cyclamate and lactisole have been found to bind and consequently confer the taste of sweetness .
Jiang P, Cui M, Zhao B, Snyder LA, Benard LM, Osman R, Max M, Margolskee RF; , J Biol Chem. 2005;280:34296-34305.: Identification of the cyclamate interaction site within the transmembrane domain of the human sweet taste receptor subunit T1R3. PUBMED:16076846 EPMC:16076846
Internal database links
|SCOOP:||7tm_2 ANF_receptor NCD3G|
External database links
This tab holds annotation information from the InterPro database.
InterPro entry IPR017978
GPCR family 3 receptors (also known as family C) are structurally similar to other GPCRs, but do not show any significant sequence similarity and thus represent a distinct group. Structurally they are composed of four elements; an N-terminal signal sequence; a large hydrophilic extracellular agonist-binding region containing several conserved cysteine residues which could be involved in disulphide bonds; a shorter region containing seven transmembrane domains; and a C-terminal cytoplasmic domain of variable length [ PUBMED:17266540 ]. Family 3 members include the metabotropic glutamate receptors, the extracellular calcium-sensing receptors, the gamma-amino-butyric acid (GABA) type B receptors, and the vomeronasal type-2 receptors [ PUBMED:1309649 , PUBMED:8255296 , PUBMED:10773016 , PUBMED:9292726 ]. As these receptors regulate many important physiological processes they are potentially promising targets for drug development.
G protein-coupled receptors (GPCRs) constitute a vast protein family that encompasses a wide range of functions, including various autocrine, paracrine and endocrine processes. They show considerable diversity at the sequence level, on the basis of which they can be separated into distinct groups [ PUBMED:12679517 ]. The term clan can be used to describe the GPCRs, as they embrace a group of families for which there are indications of evolutionary relationship, but between which there is no statistically significant similarity in sequence [ PUBMED:8170923 ]. The currently known clan members include rhodopsin-like GPCRs (Class A, GPCRA), secretin-like GPCRs (Class B, GPCRB), metabotropic glutamate receptor family (Class C, GPCRC), fungal mating pheromone receptors (Class D, GPCRD), cAMP receptors (Class E, GPCRE) and frizzled/smoothened (Class F, GPCRF) [ PUBMED:8170923 , PUBMED:8081729 , PUBMED:15914470 , PUBMED:18948278 , PUBMED:16753280 ]. GPCRs are major drug targets, and are consequently the subject of considerable research interest. It has been reported that the repertoire of GPCRs for endogenous ligands consists of approximately 400 receptors in humans and mice [ PUBMED:12679517 ]. Most GPCRs are identified on the basis of their DNA sequences, rather than the ligand they bind, those that are unmatched to known natural ligands are designated by as orphan GPCRs, or unclassified GPCRs [ PUBMED:23020293 ].
This entry represents the C-terminal region of family 3 GPCR receptor proteins, which contains the seven transmembrane region. The seven TM regions assemble in such a way as to produce a docking pocket into which such molecules as cyclamate and lactisole have been found to bind and consequently confer the taste of sweetness [ PUBMED:16076846 ].
The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.
|Cellular component||integral component of membrane (GO:0016021)|
|Molecular function||G protein-coupled receptor activity (GO:0004930)|
|Biological process||G protein-coupled receptor signaling pathway (GO:0007186)|
Below is a listing of the unique domain organisations or architectures in which this domain is found. More...
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This clan contains various seven-transmembrane receptors and related proteins. A major member is Pfam:PF00001, members of which have been considered to be typical members of the rhodopsin superfamily. Many members of this clan are Caenorhabditis proteins, suggesting great expansion of the relevant families in these nematode worms.
The clan contains the following 53 members:7TM-7TMR_HD 7tm_1 7tm_2 7tm_3 7tm_4 7TM_GPCR_Sra 7TM_GPCR_Srab 7TM_GPCR_Srb 7TM_GPCR_Srbc 7TM_GPCR_Srd 7TM_GPCR_Srh 7TM_GPCR_Sri 7TM_GPCR_Srj 7TM_GPCR_Srsx 7TM_GPCR_Srt 7TM_GPCR_Sru 7TM_GPCR_Srv 7TM_GPCR_Srw 7TM_GPCR_Srx 7TM_GPCR_Srz 7TM_GPCR_Str 7TMR-DISM_7TM Bac_rhodopsin Ceramidase Chs7 Dicty_CAR DUF1182 DUF3522 DUF621 Frizzled Git3 GpcrRhopsn4 GPR_Gpa2_C Heliorhodopsin HisKA_7TM HlyIII Lung_7-TM_R MASE3 MASE4 Ocular_alb Per1 Pombe_5TM Serpentine_r_xa SID-1_RNA_chan Solute_trans_a Sre Srg STE3 TAS2R THH1_TOM1-3_dom TMEM187 Tmemb_40 V1R
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1Cannot generate PP/Heatmap alignments for seeds; no PP data available
Key: available, not generated, — not available.
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This page displays the phylogenetic tree for this family's seed alignment. We use FastTree to calculate neighbour join trees with a local bootstrap based on 100 resamples (shown next to the tree nodes). FastTree calculates approximately-maximum-likelihood phylogenetic trees from our seed alignment.
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|Number in seed:||616|
|Number in full:||20570|
|Average length of the domain:||244.1 aa|
|Average identity of full alignment:||26 %|
|Average coverage of the sequence by the domain:||30.61 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 61295632 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||25|
|Download:||download the raw HMM for this family|
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Unmapped species names
The tree is built by looking at each sequence in the full alignment for the family. We take the name of the species given by UniProt and try to map that to the full taxonomic tree from NCBI. In some cases, the name chosen by UniProt does not map to any node in the NCBI tree, perhaps because the chosen name is listed as a synonym or a misspelling in the NCBI taxonomy.
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Since we reduce the species tree to only the eight main taxonomic levels, sequences that are mapped to the sub-species level in the tree would not normally be shown. Rather than leave out these species, we map them instead to their parent species. So, for example, for sequences belonging to one of the Vibrio cholerae sub-species in the NCBI taxonomy, we show them instead as belonging to the species Vibrio cholerae.
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The tree shows the occurrence of this domain across different species. More...
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For all of the domain matches in a full alignment, we count the number that are found on all sequences in the alignment. This total is shown in the purple box.
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For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the 7tm_3 domain has been found. There are 75 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein sequence.
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AlphaFold Structure Predictions
The list of proteins below match this family and have AlphaFold predicted structures. Click on the protein accession to view the predicted structure.