Summary: Serpentine type 7TM GPCR chemoreceptor Sra
This is the Wikipedia entry entitled "Nematode chemoreceptor". More...
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Nematode chemoreceptor Edit Wikipedia article
|Nematode chemoreceptor, Sra|
Animals recognise a wide variety of chemicals using their senses of taste and smell. The nematode Caenorhabditis elegans has only 14 types of chemosensory neuron, yet is able to respond to dozens of chemicals because each neuron detects several stimuli. More than 40 highly divergent transmembrane proteins that could contribute to this functional diversity have been described. Most of the candidate receptor genes are in clusters of similar genes; 11 of these appear to be expressed in small subsets of chemosensory neurons. A single type of neuron can potentially express at least 4 different receptor genes. Some of these might encode receptors for water-soluble attractants, repellents and pheromones, which are divergent members of the G-protein-coupled receptor family. Sequences of the Sra family of C.elegans receptor-like proteins contain 6-7 hydrophobic, putative transmembrane, regions. These can be distinguished from other 7TM proteins (especially those known to couple G-proteins) by their own characteristic TM signatures.
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Serpentine type 7TM GPCR chemoreceptor Sra Provide feedback
Chemoreception is mediated in Caenorhabditis elegans by members of the seven-transmembrane G-protein-coupled receptor class (7TM GPCRs) of proteins which are of the serpentine type . Sra is part of the Sra superfamily of chemoreceptors. Chemoperception is one of the central senses of soil nematodes like C. elegans which are otherwise 'blind' and 'deaf' .
Troemel ER, Chou JH, Dwyer ND, Colbert HA, Bargmann CI; , Cell 1995;83:207-218.: Divergent seven transmembrane receptors are candidate chemosensory receptors in C. elegans. PUBMED:7585938 EPMC:7585938
Chen N, Pai S, Zhao Z, Mah A, Newbury R, Johnsen RC, Altun Z, Moerman DG, Baillie DL, Stein LD; , Proc Natl Acad Sci U S A. 2005;102:146-151.: Identification of a nematode chemosensory gene family. PUBMED:15618405 EPMC:15618405
External database links
This tab holds annotation information from the InterPro database.
InterPro entry IPR000344
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. We use the term clan 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 the rhodopsin-like GPCRs, the secretin-like GPCRs, the cAMP receptors, the fungal mating pheromone receptors, and the metabotropic glutamate receptor family. There is a specialised database for GPCRs (http://www.gpcr.org/7tm/).
The nematode Caenorhabditis elegans has only 14 types of chemosensory neuron, yet is able to sense and respond to several hundred different chemicals because each neuron detects several stimuli [PUBMED:10580986]. Chemoperception is one of the central senses of soil nematodes like C. elegans which are otherwise 'blind' and 'deaf' [PUBMED:18050473]. Chemoreception in C. elegans is mediated by members of the seven-transmembrane G-protein-coupled receptor class (7TM GPCRs). More than 1300 potential chemoreceptor genes have been identified in C. elegans, which are generally prefixed sr for serpentine receptor. The receptor superfamilies include Sra (Sra, Srb, Srab, Sre), Str (Srh, Str, Sri, Srd, Srj, Srm, Srn) and Srg (Srx, Srt, Srg, Sru, Srv, Srxa), as well as the families Srw, Srz, Srbc, Srsx and Srr [PUBMED:7585938, PUBMED:18050473, PUBMED:15618405]. Many of these proteins have homologues in Caenorhabditis briggsae.
This entry represents serpentine receptor class a (Sra) from the Sra superfamily [PUBMED:15618405]. Sra receptors contain 6-7 hydrophobic, putative transmembrane, regions and can be distinguished from other 7TM GPCR receptors by their own characteristic TM signatures.
The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.
|Cellular component||integral to membrane (GO:0016021)|
|Molecular function||transmembrane signaling receptor activity (GO:0004888)|
|Biological process||sensory perception of chemical stimulus (GO:0007606)|
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|Previous IDs:||Sra; 7TM_GCPR_Sra;|
|Author:||Mian N, Bateman A|
|Number in seed:||10|
|Number in full:||141|
|Average length of the domain:||276.40 aa|
|Average identity of full alignment:||20 %|
|Average coverage of the sequence by the domain:||94.23 %|
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build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 23193494 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||11|
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