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class="mw-page-title-main">Orphan receptor</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Go to an article in another language. Available in 11 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-11" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">11 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D9%85%D8%B3%D8%AA%D9%82%D8%A8%D9%84_%D9%8A%D8%AA%D9%8A%D9%85" title="مستقبل يتيم – Arabic" lang="ar" hreflang="ar" data-title="مستقبل يتيم" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Orphan-Rezeptor" title="Orphan-Rezeptor – German" lang="de" hreflang="de" data-title="Orphan-Rezeptor" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Receptor_hu%C3%A9rfano" title="Receptor huérfano – Spanish" lang="es" hreflang="es" data-title="Receptor huérfano" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%DA%AF%DB%8C%D8%B1%D9%86%D8%AF%D9%87_%DB%8C%D8%AA%DB%8C%D9%85" title="گیرنده یتیم – Persian" lang="fa" hreflang="fa" data-title="گیرنده یتیم" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/R%C3%A9cepteur_orphelin" title="Récepteur orphelin – French" lang="fr" hreflang="fr" data-title="Récepteur orphelin" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-gl mw-list-item"><a href="https://gl.wikipedia.org/wiki/Receptor_orfo" title="Receptor orfo – Galician" lang="gl" hreflang="gl" data-title="Receptor orfo" data-language-autonym="Galego" data-language-local-name="Galician" class="interlanguage-link-target"><span>Galego</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E3%82%AA%E3%83%BC%E3%83%95%E3%82%A1%E3%83%B3%E5%8F%97%E5%AE%B9%E4%BD%93" title="オーファン受容体 – Japanese" lang="ja" hreflang="ja" data-title="オーファン受容体" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%9E%D1%80%D1%84%D0%B0%D0%BD%D0%BD%D1%8B%D0%B5_%D1%80%D0%B5%D1%86%D0%B5%D0%BF%D1%82%D0%BE%D1%80%D1%8B" title="Орфанные рецепторы – Russian" lang="ru" hreflang="ru" data-title="Орфанные рецепторы" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/Orfan_receptor" title="Orfan receptor – Serbian" lang="sr" hreflang="sr" data-title="Orfan receptor" data-language-autonym="Српски / srpski" data-language-local-name="Serbian" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-sh mw-list-item"><a href="https://sh.wikipedia.org/wiki/Orfanski_receptor" title="Orfanski receptor – Serbo-Croatian" lang="sh" hreflang="sh" data-title="Orfanski receptor" data-language-autonym="Srpskohrvatski / српскохрватски" data-language-local-name="Serbo-Croatian" class="interlanguage-link-target"><span>Srpskohrvatski / српскохрватски</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%E5%AD%A4%E5%84%BF%E5%8F%97%E4%BD%93" title="孤儿受体 – Chinese" lang="zh" hreflang="zh" data-title="孤儿受体" data-language-autonym="中文" data-language-local-name="Chinese" class="interlanguage-link-target"><span>中文</span></a></li> </ul> <div class="after-portlet after-portlet-lang"><span class="wb-langlinks-edit wb-langlinks-link"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q2496179#sitelinks-wikipedia" title="Edit interlanguage links" class="wbc-editpage">Edit links</a></span></div> </div> </div> </div> </header> <div class="vector-page-toolbar"> <div class="vector-page-toolbar-container"> <div id="left-navigation"> <nav aria-label="Namespaces"> <div 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data-file-width="360" data-file-height="290" /></span></span></div></td><td class="mbox-text"><div class="mbox-text-span">This article needs to be <b>updated</b>. The reason given is: Ligands are now partially identified along with a few other new discoveries.<span class="hide-when-compact"> Please help update this article to reflect recent events or newly available information.</span> <span class="date-container"><i>(<span class="date">March 2024</span>)</i></span></div></td></tr></tbody></table> <p>In <a href="/wiki/Biochemistry" title="Biochemistry">biochemistry</a>, an <b>orphan receptor</b> is a protein that has a similar structure to other identified <a href="/wiki/Receptor_(biochemistry)" title="Receptor (biochemistry)">receptors</a> but whose <a href="/wiki/Endogenous" class="mw-redirect" title="Endogenous">endogenous</a> <a href="/wiki/Ligand_(biochemistry)" title="Ligand (biochemistry)">ligand</a> has not yet been identified. If a ligand for an orphan receptor is later discovered, the receptor is referred to as an "adopted orphan".<sup id="cite_ref-Nanduri2015_1-0" class="reference"><a href="#cite_note-Nanduri2015-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> Conversely, the term <b>orphan ligand</b> refers to a biological ligand whose cognate receptor has not yet been identified. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Examples">Examples</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Orphan_receptor&action=edit&section=1" title="Edit section: Examples"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Examples of orphan receptors are found in the <a href="/wiki/G_protein-coupled_receptor" title="G protein-coupled receptor">G protein-coupled receptor</a> (GPCR)<sup id="cite_ref-Levoye_2006_2-0" class="reference"><a href="#cite_note-Levoye_2006-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Civelli_2006_3-0" class="reference"><a href="#cite_note-Civelli_2006-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Wise_2004_4-0" class="reference"><a href="#cite_note-Wise_2004-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> and <a href="/wiki/Nuclear_receptor" title="Nuclear receptor">nuclear receptor</a><sup id="cite_ref-pmid10529899_5-0" class="reference"><a href="#cite_note-pmid10529899-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Benoit_2006_6-0" class="reference"><a href="#cite_note-Benoit_2006-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-pmid17532527_7-0" class="reference"><a href="#cite_note-pmid17532527-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> families. </p><p>If an endogenous ligand is found, the orphan receptor is "adopted" or "de-orphanized".<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> An example is the nuclear receptor <a href="/wiki/Farnesoid_X_receptor" title="Farnesoid X receptor">farnesoid X receptor</a> (FXR) and the GPCR <a href="/wiki/G_protein-coupled_bile_acid_receptor" title="G protein-coupled bile acid receptor">TGR5/GPCR19/G protein-coupled bile acid receptor</a>, both of which are activated by <a href="/wiki/Bile_acid" title="Bile acid">bile acids</a>.<sup id="cite_ref-pmid12718893_9-0" class="reference"><a href="#cite_note-pmid12718893-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> Adopted orphan receptors in the <a href="/wiki/Nuclear_receptor" title="Nuclear receptor">nuclear receptor</a> group include FXR, <a href="/wiki/Liver_X_receptor" title="Liver X receptor">liver X receptor</a> (LXR), and <a href="/wiki/Peroxisome_proliferator-activated_receptor" title="Peroxisome proliferator-activated receptor">peroxisome proliferator-activated receptor</a> (PPAR). Another example of an orphan receptor site is the <a href="/wiki/Phencyclidine" title="Phencyclidine">PCP</a> binding site in the <a href="/wiki/NMDA_receptor" title="NMDA receptor">NMDA receptor</a>,<sup id="cite_ref-pmid2438606_10-0" class="reference"><a href="#cite_note-pmid2438606-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> a type of <a href="/wiki/Ligand-gated_ion_channel" title="Ligand-gated ion channel">ligand-gated ion channel</a>. This site is where the recreational drug PCP works, but no endogenous ligand is known to bind to this site. </p><p>GPCR orphan receptors are usually given the name "GPR" followed by a number, for example <a href="/wiki/GPR1" title="GPR1">GPR1</a>. In the GPCR family, nearly 100 receptor-like genes remain orphans.<sup id="cite_ref-pmid29454621_11-0" class="reference"><a href="#cite_note-pmid29454621-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Discovery">Discovery</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Orphan_receptor&action=edit&section=2" title="Edit section: Discovery"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Historically, receptors were discovered by using ligands to "fish" for their receptors. Hence, by definition, these receptors were not orphans. However, with modern molecular biology techniques such as <a href="/wiki/Reverse_pharmacology" title="Reverse pharmacology">reverse pharmacology</a>, screening of <a href="/wiki/CDNA_library" title="CDNA library">cDNA libraries</a>, and <a href="/wiki/Whole_genome_sequencing" title="Whole genome sequencing">whole genome sequencing</a>, receptors have been identified based on sequence similarity to known receptors, without knowing what their ligands are. </p> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Orphan_receptor&action=edit&section=3" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist reflist-columns references-column-width reflist-columns-2"> <ol class="references"> <li id="cite_note-Nanduri2015-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-Nanduri2015_1-0">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFNanduriBhutaniSomavarapuMahajan2015" class="citation journal cs1">Nanduri, Ravikanth; 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"The G protein-coupled receptors deorphanization landscape". <i>Biochemical Pharmacology</i>. <b>153</b>: 62–74. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1016%2Fj.bcp.2018.02.016">10.1016/j.bcp.2018.02.016</a>. <a href="/wiki/PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/29454621">29454621</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:3566341">3566341</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Biochemical+Pharmacology&rft.atitle=The+G+protein-coupled+receptors+deorphanization+landscape&rft.volume=153&rft.pages=62-74&rft.date=2018&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A3566341%23id-name%3DS2CID&rft_id=info%3Apmid%2F29454621&rft_id=info%3Adoi%2F10.1016%2Fj.bcp.2018.02.016&rft.aulast=Laschet&rft.aufirst=C&rft.au=Dupuis%2C+N&rft.au=Hanson%2C+J&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOrphan+receptor" class="Z3988"></span></span> </li> </ol></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Orphan_receptor&action=edit&section=4" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.guidetopharmacology.org/GRAC/FamilyDisplayForward?familyId=16">"Class A Orphans GPCRs"</a>. <i>IUPHAR/BPS Guide to PHARMACOLOGY Database</i>. University of Edinburgh / International Union of Basic and Clinical Pharmacology.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IUPHAR%2FBPS+Guide+to+PHARMACOLOGY+Database&rft.atitle=Class+A+Orphans+GPCRs&rft_id=http%3A%2F%2Fwww.guidetopharmacology.org%2FGRAC%2FFamilyDisplayForward%3FfamilyId%3D16&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOrphan+receptor" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.guidetopharmacology.org/GRAC/FamilyDisplayForward?familyId=17">"Adhesion Class GPCRs"</a>. <i>IUPHAR/BPS Guide to PHARMACOLOGY Database</i>. University of Edinburgh / International Union of Basic and Clinical Pharmacology.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IUPHAR%2FBPS+Guide+to+PHARMACOLOGY+Database&rft.atitle=Adhesion+Class+GPCRs&rft_id=http%3A%2F%2Fwww.guidetopharmacology.org%2FGRAC%2FFamilyDisplayForward%3FfamilyId%3D17&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOrphan+receptor" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.guidetopharmacology.org/GRAC/FamilyDisplayForward?familyId=18">"Class C Orphans GPCRs"</a>. <i>IUPHAR/BPS Guide to PHARMACOLOGY Database</i>. University of Edinburgh / International Union of Basic and Clinical Pharmacology.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=IUPHAR%2FBPS+Guide+to+PHARMACOLOGY+Database&rft.atitle=Class+C+Orphans+GPCRs&rft_id=http%3A%2F%2Fwww.guidetopharmacology.org%2FGRAC%2FFamilyDisplayForward%3FfamilyId%3D18&rfr_id=info%3Asid%2Fen.wikipedia.org%3AOrphan+receptor" class="Z3988"></span></li></ul> <div style="clear:both;" class=""></div> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl 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style="font-size:114%;margin:0 4em"><a href="/wiki/Rhodopsin-like_receptors" title="Rhodopsin-like receptors">Class A</a>: <a href="/wiki/Rhodopsin" title="Rhodopsin">Rhodopsin</a>-like</div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:7em;text-align:left;"><a href="/wiki/Neurotransmitter_receptor" title="Neurotransmitter receptor">Neurotransmitter</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:7em;text-align:left;"><a href="/wiki/Adrenergic_receptor" title="Adrenergic receptor">Adrenergic</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Alpha-1_adrenergic_receptor" title="Alpha-1 adrenergic receptor">α1</a> (<a href="/wiki/Alpha-1A_adrenergic_receptor" title="Alpha-1A adrenergic receptor">A</a></li> <li><a href="/wiki/Alpha-1B_adrenergic_receptor" title="Alpha-1B adrenergic receptor">B</a></li> <li><a href="/wiki/Alpha-1D_adrenergic_receptor" title="Alpha-1D adrenergic receptor">D</a>)</li> <li><a href="/wiki/Alpha-2_adrenergic_receptor" title="Alpha-2 adrenergic receptor">α2</a> (<a href="/wiki/Alpha-2A_adrenergic_receptor" title="Alpha-2A adrenergic receptor">A</a></li> <li><a href="/wiki/Alpha-2B_adrenergic_receptor" title="Alpha-2B adrenergic receptor">B</a></li> <li><a href="/wiki/Alpha-2C_adrenergic_receptor" title="Alpha-2C adrenergic receptor">C</a>)</li> <li><a href="/wiki/Beta-1_adrenergic_receptor" title="Beta-1 adrenergic receptor">β1</a></li> <li><a href="/wiki/Beta-2_adrenergic_receptor" title="Beta-2 adrenergic receptor">β2</a></li> <li><a href="/wiki/Beta-3_adrenergic_receptor" title="Beta-3 adrenergic receptor">β3</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:7em;text-align:left;"><a href="/wiki/Purinergic_receptor" title="Purinergic receptor">Purinergic</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Adenosine_receptor" title="Adenosine receptor">Adenosine</a> (<a href="/wiki/Adenosine_A1_receptor" title="Adenosine A1 receptor">A1</a></li> <li><a href="/wiki/Adenosine_A2A_receptor" title="Adenosine A2A receptor">A2A</a></li> <li><a href="/wiki/Adenosine_A2B_receptor" title="Adenosine A2B receptor">A2B</a></li> <li><a href="/wiki/Adenosine_A3_receptor" title="Adenosine A3 receptor">A3</a>)</li> <li><a href="/wiki/P2Y_receptor" title="P2Y receptor">P2Y</a> (<a href="/wiki/P2RY1" title="P2RY1">1</a></li> <li><a href="/wiki/P2RY2" title="P2RY2">2</a></li> <li><a href="/wiki/P2RY4" title="P2RY4">4</a></li> <li><a href="/wiki/LPAR6" title="LPAR6">5</a></li> <li><a href="/wiki/P2RY6" title="P2RY6">6</a></li> <li><a href="/wiki/P2RY8" title="P2RY8">8</a></li> <li><a href="/wiki/GPR23" class="mw-redirect" title="GPR23">9</a></li> <li><a href="/wiki/P2RY10" title="P2RY10">10</a></li> <li><a href="/wiki/P2RY11" title="P2RY11">11</a></li> <li><a href="/wiki/P2Y12" title="P2Y12">12</a></li> <li><a href="/wiki/P2RY13" title="P2RY13">13</a></li> <li><a href="/wiki/P2RY14" title="P2RY14">14</a>)</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:7em;text-align:left;"><a href="/wiki/5-HT_receptor" title="5-HT receptor">Serotonin</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><i>(all but <a href="/wiki/5-HT3_receptor" title="5-HT3 receptor">5-HT3</a>)</i> <a href="/wiki/5-HT1_receptor" title="5-HT1 receptor">5-HT1</a> (<a href="/wiki/5-HT1A_receptor" title="5-HT1A receptor">A</a></li> <li><a href="/wiki/5-HT1B_receptor" title="5-HT1B receptor">B</a></li> <li><a href="/wiki/5-HT1D_receptor" title="5-HT1D receptor">D</a></li> <li><a href="/wiki/5-HT1E_receptor" title="5-HT1E receptor">E</a></li> <li><a href="/wiki/5-HT1F_receptor" title="5-HT1F receptor">F</a>)</li> <li><a href="/wiki/5-HT2_receptor" title="5-HT2 receptor">5-HT2</a> (<a href="/wiki/5-HT2A_receptor" title="5-HT2A receptor">A</a></li> <li><a href="/wiki/5-HT2B_receptor" title="5-HT2B receptor">B</a></li> <li><a href="/wiki/5-HT2C_receptor" title="5-HT2C receptor">C</a>)</li> <li><i>5-HT</i> (<a href="/wiki/5-HT4_receptor" title="5-HT4 receptor">4</a></li> <li><a href="/wiki/5-HT5A_receptor" title="5-HT5A receptor">5A</a></li> <li><a href="/wiki/5-HT6_receptor" title="5-HT6 receptor">6</a></li> <li><a href="/wiki/5-HT7_receptor" title="5-HT7 receptor">7</a>)</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:7em;text-align:left;">Other</th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Muscarinic_acetylcholine_receptor" title="Muscarinic acetylcholine receptor">Acetylcholine</a> (<a href="/wiki/Muscarinic_acetylcholine_receptor_M1" title="Muscarinic acetylcholine receptor M1">M1</a></li> <li><a href="/wiki/Muscarinic_acetylcholine_receptor_M2" title="Muscarinic acetylcholine receptor M2">M2</a></li> <li><a href="/wiki/Muscarinic_acetylcholine_receptor_M3" title="Muscarinic acetylcholine receptor M3">M3</a></li> <li><a href="/wiki/Muscarinic_acetylcholine_receptor_M4" title="Muscarinic acetylcholine receptor M4">M4</a></li> <li><a href="/wiki/Muscarinic_acetylcholine_receptor_M5" title="Muscarinic acetylcholine receptor M5">M5</a>)</li> <li><a href="/wiki/Dopamine_receptor" title="Dopamine receptor">Dopamine</a> <ul><li><a href="/wiki/Dopamine_receptor_D1" title="Dopamine receptor D1">D1</a></li> <li><a href="/wiki/Dopamine_receptor_D2" title="Dopamine receptor D2">D2</a></li> <li><a href="/wiki/Dopamine_receptor_D3" title="Dopamine receptor D3">D3</a></li> <li><a href="/wiki/Dopamine_receptor_D4" title="Dopamine receptor D4">D4</a></li> <li><a href="/wiki/Dopamine_receptor_D5" title="Dopamine receptor D5">D5</a></li></ul></li> <li><a href="/wiki/GHB_receptor" title="GHB receptor">GHB receptor</a></li> <li><a href="/wiki/Histamine_receptor" title="Histamine receptor">Histamine</a> <ul><li><a href="/wiki/Histamine_H1_receptor" title="Histamine H1 receptor">H1</a></li> <li><a href="/wiki/Histamine_H2_receptor" title="Histamine H2 receptor">H2</a></li> <li><a href="/wiki/Histamine_H3_receptor" title="Histamine H3 receptor">H3</a></li> <li><a href="/wiki/Histamine_H4_receptor" title="Histamine H4 receptor">H4</a></li></ul></li> <li><a href="/wiki/Melatonin_receptor" title="Melatonin receptor">Melatonin</a> (<a href="/wiki/Melatonin_receptor_1A" title="Melatonin receptor 1A">1A</a></li> <li><a href="/wiki/Melatonin_receptor_1B" title="Melatonin receptor 1B">1B</a></li> <li><a href="/wiki/Melatonin_receptor_1C" title="Melatonin receptor 1C">1C</a>)</li> <li><a href="/wiki/Trace_amine-associated_receptor" title="Trace amine-associated receptor">TAAR</a> (<a href="/wiki/TAAR1" title="TAAR1">1</a></li> <li><a href="/wiki/TAAR2" title="TAAR2">2</a></li> <li><a href="/wiki/TAAR5" title="TAAR5">5</a></li> <li><a href="/wiki/TAAR6" title="TAAR6">6</a></li> <li><a href="/wiki/TAAR8" title="TAAR8">8</a></li> <li><a href="/wiki/TAAR9" title="TAAR9">9</a>)</li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:7em;text-align:left;">Metabolites and<br />signaling molecules</th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:7em;text-align:left;"><a href="/wiki/Eicosanoid_receptor" title="Eicosanoid receptor">Eicosanoid</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><i>CysLT</i> (<a href="/wiki/Cysteinyl_leukotriene_receptor_1" title="Cysteinyl leukotriene receptor 1">1</a></li> <li><a href="/wiki/Cysteinyl_leukotriene_receptor_2" title="Cysteinyl leukotriene receptor 2">2</a>)</li> <li><a href="/wiki/Leukotriene_B4" title="Leukotriene B4">LTB4</a> <ul><li><a href="/wiki/Leukotriene_B4_receptor" title="Leukotriene B4 receptor">1</a></li> <li><a href="/wiki/Leukotriene_B4_receptor_2" title="Leukotriene B4 receptor 2">2</a></li></ul></li> <li><a href="/wiki/Formyl_peptide_receptor_2" title="Formyl peptide receptor 2"> FPRL1</a></li> <li><a href="/wiki/Oxoeicosanoid_receptor_1" title="Oxoeicosanoid receptor 1">OXE</a></li> <li><a href="/wiki/Prostaglandin_receptor" title="Prostaglandin receptor">Prostaglandin</a> <ul><li><i>DP</i> (<a href="/wiki/Prostaglandin_D2_receptor" title="Prostaglandin D2 receptor">1</a></li> <li><a href="/wiki/GPR44" class="mw-redirect" title="GPR44">2</a>), <i>EP</i> (<a href="/wiki/EP1_receptor" class="mw-redirect" title="EP1 receptor">1</a></li> <li><a href="/wiki/Prostaglandin_E2_receptor" title="Prostaglandin E2 receptor">2</a></li> <li><a href="/wiki/Prostaglandin_E_receptor_3" class="mw-redirect" title="Prostaglandin E receptor 3">3</a></li> <li><a href="/wiki/EP4_receptor" class="mw-redirect" title="EP4 receptor">4</a>), <a href="/wiki/Prostaglandin_F_receptor" title="Prostaglandin F receptor">FP</a></li></ul></li> <li><a href="/wiki/Prostacyclin_receptor" title="Prostacyclin receptor">Prostacyclin</a></li> <li><a href="/wiki/Thromboxane_receptor" title="Thromboxane receptor">Thromboxane</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:7em;text-align:left;">Other</th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/G_protein-coupled_bile_acid_receptor" title="G protein-coupled bile acid receptor">Bile acid</a></li> <li><a href="/wiki/Cannabinoid_receptor" title="Cannabinoid receptor">Cannabinoid</a> (<a href="/wiki/Cannabinoid_receptor_type_1" class="mw-redirect" title="Cannabinoid receptor type 1">CB1</a></li> <li><a href="/wiki/Cannabinoid_receptor_type_2" class="mw-redirect" title="Cannabinoid receptor type 2">CB2</a>, <i>GPR</i> (<a href="/wiki/GPR18" class="mw-redirect" title="GPR18">18</a></li> <li><a href="/wiki/GPR55" title="GPR55">55</a></li> <li><a href="/wiki/GPR119" title="GPR119">119</a>))</li> <li><a href="/wiki/GPR183" title="GPR183">EBI2</a></li> <li><a href="/wiki/GPER" title="GPER">Estrogen</a></li> <li><a href="/wiki/Free_fatty_acid_receptor" title="Free fatty acid receptor">Free fatty acid</a> (<a href="/wiki/Free_fatty_acid_receptor_1" title="Free fatty acid receptor 1">1</a></li> <li><a href="/wiki/Free_fatty_acid_receptor_2" title="Free fatty acid receptor 2">2</a></li> <li><a href="/wiki/Free_fatty_acid_receptor_3" title="Free fatty acid receptor 3">3</a></li> <li><a href="/wiki/GPR42" title="GPR42">4</a>)</li> <li><a href="/wiki/Hydroxycarboxylic_acid_receptor" title="Hydroxycarboxylic acid receptor">Hydroxycarboxylic acids</a> <ul><li><a href="/wiki/Hydroxycarboxylic_acid_receptor_1" title="Hydroxycarboxylic acid receptor 1">1</a></li> <li><a href="/wiki/Hydroxycarboxylic_acid_receptor_2" title="Hydroxycarboxylic acid receptor 2">2</a></li> <li><a href="/wiki/Hydroxycarboxylic_acid_receptor_3" title="Hydroxycarboxylic acid receptor 3">3</a></li></ul></li> <li><a href="/wiki/Lysophosphatidic_acid" title="Lysophosphatidic acid">Lysophosphatidic acid</a> (<a href="/wiki/LPAR1" title="LPAR1">1</a></li> <li><a href="/wiki/LPAR2" title="LPAR2">2</a></li> <li><a href="/wiki/LPAR3" title="LPAR3">3</a></li> <li><a href="/wiki/LPAR4" title="LPAR4">4</a></li> <li><a href="/wiki/LPAR5" title="LPAR5">5</a></li> <li><a href="/wiki/LPAR6" title="LPAR6">6</a>)</li> <li><a href="/wiki/Lysophospholipid_receptor" title="Lysophospholipid receptor">Lysophospholipid</a> (<a href="/wiki/S1PR1" title="S1PR1">1</a></li> <li><a href="/wiki/LPAR1" title="LPAR1">2</a></li> <li><a href="/wiki/S1PR3" title="S1PR3">3</a></li> <li><a href="/wiki/LPAR2" title="LPAR2">4</a></li> <li><a href="/wiki/S1PR2" title="S1PR2">5</a></li> <li><a href="/wiki/S1PR4" title="S1PR4">6</a></li> <li><a href="/wiki/LPAR3" title="LPAR3">7</a></li> <li><a href="/wiki/S1PR5" title="S1PR5">8</a>)</li> <li><a href="/wiki/OXGR1" title="OXGR1">Oxoglutarate</a></li> <li><a href="/wiki/Platelet-activating_factor_receptor" title="Platelet-activating factor receptor">PAF</a></li> <li><a href="/wiki/Sphingosine-1-phosphate" title="Sphingosine-1-phosphate">Sphingosine-1-phosphate</a> (<a href="/wiki/S1PR1" title="S1PR1">1</a></li> <li><a href="/wiki/S1PR2" title="S1PR2">2</a></li> <li><a href="/wiki/S1PR3" title="S1PR3">3</a></li> <li><a href="/wiki/S1PR4" title="S1PR4">4</a></li> <li><a href="/wiki/S1PR5" title="S1PR5">5</a>)</li> <li><a href="/wiki/SUCNR1" title="SUCNR1">Succinate</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:7em;text-align:left;">Peptide</th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:7em;text-align:left;"><a href="/wiki/GPCR_neuropeptide_receptor" title="GPCR neuropeptide receptor">Neuropeptide</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Neuropeptide_B/W_receptor" title="Neuropeptide B/W receptor">B/W</a> (<a href="/wiki/Neuropeptides_B/W_receptor_1" title="Neuropeptides B/W receptor 1">1</a></li> <li><a href="/wiki/Neuropeptides_B/W_receptor_2" title="Neuropeptides B/W receptor 2">2</a>)</li> <li><a href="/wiki/Neuropeptide_FF_receptor" title="Neuropeptide FF receptor">FF</a> (<a href="/wiki/Neuropeptide_FF_receptor_1" title="Neuropeptide FF receptor 1">1</a></li> <li><a href="/wiki/Neuropeptide_FF_receptor_2" title="Neuropeptide FF receptor 2">2</a>)</li> <li><a href="/wiki/Neuropeptide_S_receptor" title="Neuropeptide S receptor">S</a></li> <li><a href="/wiki/Neuropeptide_Y_receptor" title="Neuropeptide Y receptor">Y</a> (<a href="/wiki/Neuropeptide_Y_receptor_Y1" title="Neuropeptide Y receptor Y1">1</a></li> <li><a href="/wiki/Neuropeptide_Y_receptor_Y2" title="Neuropeptide Y receptor Y2">2</a></li> <li><a href="/wiki/Pancreatic_polypeptide_receptor_1" title="Pancreatic polypeptide receptor 1">4</a></li> <li><a href="/wiki/Neuropeptide_Y_receptor_Y5" title="Neuropeptide Y receptor Y5">5</a>)</li> <li><i>Neuromedin</i> (<a href="/wiki/Neuromedin_B_receptor" title="Neuromedin B receptor">B</a></li> <li><a href="/wiki/Neuromedin_U_receptor" title="Neuromedin U receptor">U</a> (<a href="/wiki/Neuromedin_U_receptor_1" title="Neuromedin U receptor 1">1</a></li> <li><a href="/wiki/Neuromedin_U_receptor_2" title="Neuromedin U receptor 2">2</a>))</li> <li><a href="/wiki/Neurotensin_receptor" title="Neurotensin receptor">Neurotensin</a> (<a href="/wiki/Neurotensin_receptor_1" title="Neurotensin receptor 1">1</a></li> <li><a href="/wiki/Neurotensin_receptor_2" title="Neurotensin receptor 2">2</a>)</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:7em;text-align:left;">Other</th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Anaphylatoxin_receptors" title="Anaphylatoxin receptors">Anaphylatoxin</a> (<a href="/wiki/C3a_receptor" title="C3a receptor">C3a</a></li> <li>C5a (<a href="/wiki/C5a_receptor" title="C5a receptor">1</a></li> <li><a href="/wiki/C5AR2" title="C5AR2">2</a>))</li> <li><a href="/wiki/Angiotensin_receptor" class="mw-redirect" title="Angiotensin receptor">Angiotensin</a> (<a href="/wiki/Angiotensin_II_receptor_type_1" title="Angiotensin II receptor type 1">1</a></li> <li><a href="/wiki/Angiotensin_II_receptor_type_2" title="Angiotensin II receptor type 2">2</a>)</li> <li><a href="/wiki/Apelin_receptor" title="Apelin receptor">Apelin</a></li> <li><a href="/wiki/Bombesin_receptor" title="Bombesin receptor">Bombesin</a> <ul><li><a href="/wiki/Bombesin-like_receptor_3" title="Bombesin-like receptor 3">BRS3</a></li> <li><a href="/wiki/Gastrin-releasing_peptide_receptor" title="Gastrin-releasing peptide receptor">GRPR</a></li> <li><a href="/wiki/Neuromedin_B_receptor" title="Neuromedin B receptor">NMBR</a>)</li> <li><a href="/wiki/Bradykinin_receptor" title="Bradykinin receptor">Bradykinin</a> (<a href="/wiki/Bradykinin_receptor_B1" title="Bradykinin receptor B1">B1</a></li> <li><a href="/wiki/Bradykinin_receptor_B2" title="Bradykinin receptor B2">B2</a>)</li></ul></li> <li><a href="/wiki/Chemokine_receptor" title="Chemokine receptor">Chemokine</a></li> <li><a href="/wiki/Cholecystokinin_receptor" title="Cholecystokinin receptor">Cholecystokinin</a> (<a href="/wiki/Cholecystokinin_A_receptor" title="Cholecystokinin A receptor">A</a></li> <li><a href="/wiki/Cholecystokinin_B_receptor" title="Cholecystokinin B receptor">B</a>)</li> <li><a href="/wiki/Endothelin_receptor" title="Endothelin receptor">Endothelin</a> <ul><li><a href="/wiki/Endothelin_A_receptor" title="Endothelin A receptor">A</a></li> <li><a href="/wiki/Endothelin_B_receptor" class="mw-redirect" title="Endothelin B receptor">B</a></li></ul></li> <li><a href="/wiki/Formyl_peptide_receptor" title="Formyl peptide receptor">Formyl peptide</a> (<a href="/wiki/Formyl_peptide_receptor_1" title="Formyl peptide receptor 1">1</a></li> <li><a href="/wiki/Formyl_peptide_receptor_2" title="Formyl peptide receptor 2">2</a></li> <li><a href="/wiki/Formyl_peptide_receptor_3" title="Formyl peptide receptor 3">3</a>)</li> <li><a href="/wiki/Follicle-stimulating_hormone_receptor" title="Follicle-stimulating hormone receptor">FSH</a></li> <li><a href="/wiki/Galanin_receptor" title="Galanin receptor">Galanin</a> (<a href="/wiki/Galanin_receptor_1" title="Galanin receptor 1">1</a></li> <li><a href="/wiki/Galanin_receptor_2" title="Galanin receptor 2">2</a></li> <li><a href="/wiki/Galanin_receptor_3" title="Galanin receptor 3">3</a>)</li> <li><a href="/wiki/Gonadotropin-releasing_hormone_receptor" title="Gonadotropin-releasing hormone receptor">Gonadotropin-releasing hormone</a> (<a href="/wiki/GNRHR" title="GNRHR">1</a></li> <li><a href="/wiki/GNRHR2" title="GNRHR2">2</a>)</li> <li><a href="/wiki/Growth_hormone_secretagogue_receptor" title="Growth hormone secretagogue receptor">Ghrelin</a></li> <li><a href="/wiki/KiSS1-derived_peptide_receptor" title="KiSS1-derived peptide receptor"> Kisspeptin</a></li> <li><a href="/wiki/Luteinizing_hormone/choriogonadotropin_receptor" title="Luteinizing hormone/choriogonadotropin receptor">Luteinizing hormone/choriogonadotropin</a></li> <li><a href="/wiki/MAS1_oncogene" title="MAS1 oncogene">MAS</a> (<a href="/wiki/MAS1" title="MAS1">1</a></li> <li><a href="/wiki/MAS1L" title="MAS1L">1L</a></li> <li><a href="/wiki/MRGPRD" title="MRGPRD">D</a></li> <li><a href="/wiki/MRGPRE" title="MRGPRE">E</a></li> <li><a href="/wiki/MRGPRF" title="MRGPRF">F</a></li> <li><a href="/wiki/MRGPRG" title="MRGPRG">G</a></li> <li><a href="/wiki/MRGPRX1" title="MRGPRX1">X1</a></li> <li><a href="/wiki/MRGPRX2" title="MRGPRX2">X2</a></li> <li><a href="/wiki/MRGPRX3" title="MRGPRX3">X3</a></li> <li><a href="/wiki/MRGPRX4" title="MRGPRX4">X4</a>)</li> <li><a href="/wiki/Melanocortin_receptor" title="Melanocortin receptor">Melanocortin</a> (<a href="/wiki/Melanocortin_1_receptor" title="Melanocortin 1 receptor">1</a></li> <li><a href="/wiki/ACTH_receptor" title="ACTH receptor">2</a></li> <li><a href="/wiki/Melanocortin_3_receptor" title="Melanocortin 3 receptor">3</a></li> <li><a href="/wiki/Melanocortin_4_receptor" title="Melanocortin 4 receptor">4</a></li> <li><a href="/wiki/Melanocortin_5_receptor" title="Melanocortin 5 receptor">5</a>)</li> <li><a href="/wiki/Melanin-concentrating_hormone_receptor" title="Melanin-concentrating hormone receptor">MCHR</a> (<a href="/wiki/Melanin-concentrating_hormone_receptor_1" title="Melanin-concentrating hormone receptor 1">1</a></li> <li><a href="/wiki/Melanin-concentrating_hormone_receptor_2" title="Melanin-concentrating hormone receptor 2">2</a>)</li> <li><a href="/wiki/Motilin_receptor" title="Motilin receptor">Motilin</a></li> <li><a href="/wiki/Opioid_receptor" title="Opioid receptor">Opioid</a> (<a href="/wiki/%CE%94-opioid_receptor" title="Δ-opioid receptor">Delta</a></li> <li><a href="/wiki/%CE%9A-opioid_receptor" title="Κ-opioid receptor">Kappa</a></li> <li><a href="/wiki/%CE%9C-opioid_receptor" title="Μ-opioid receptor">Mu</a></li> <li><a href="/wiki/Nociceptin_receptor" title="Nociceptin receptor">Nociceptin</a> & <a href="/wiki/OGFr" title="OGFr">Zeta</a>, but not <a href="/wiki/Sigma_receptor" title="Sigma receptor">Sigma</a>)</li> <li><a href="/wiki/Orexin_receptor" title="Orexin receptor">Orexin</a> (<a href="/wiki/Hypocretin_(orexin)_receptor_1" title="Hypocretin (orexin) receptor 1">1</a></li> <li><a href="/wiki/Hypocretin_(orexin)_receptor_2" title="Hypocretin (orexin) receptor 2">2</a>)</li> <li><a href="/wiki/Oxytocin_receptor" title="Oxytocin receptor">Oxytocin</a></li> <li><a href="/wiki/Prokineticin_receptor" title="Prokineticin receptor">Prokineticin</a> (<a href="/wiki/Prokineticin_receptor_1" title="Prokineticin receptor 1">1</a></li> <li><a href="/wiki/Prokineticin_receptor_2" title="Prokineticin receptor 2">2</a>)</li> <li><a href="/wiki/Prolactin-releasing_peptide_receptor" title="Prolactin-releasing peptide receptor">Prolactin-releasing peptide</a></li> <li><a href="/wiki/Relaxin_receptor" title="Relaxin receptor">Relaxin</a> (<a href="/wiki/Relaxin/insulin-like_family_peptide_receptor_1" title="Relaxin/insulin-like family peptide receptor 1">1</a></li> <li><a href="/wiki/Relaxin/insulin-like_family_peptide_receptor_2" title="Relaxin/insulin-like family peptide receptor 2">2</a></li> <li><a href="/wiki/Relaxin/insulin-like_family_peptide_receptor_3" title="Relaxin/insulin-like family peptide receptor 3">3</a></li> <li><a href="/wiki/Relaxin/insulin-like_family_peptide_receptor_4" title="Relaxin/insulin-like family peptide receptor 4">4</a>)</li> <li><a href="/wiki/Somatostatin_receptor" title="Somatostatin receptor">Somatostatin</a> (<a href="/wiki/Somatostatin_receptor_1" title="Somatostatin receptor 1">1</a></li> <li><a href="/wiki/Somatostatin_receptor_2" title="Somatostatin receptor 2">2</a></li> <li><a href="/wiki/Somatostatin_receptor_3" title="Somatostatin receptor 3">3</a></li> <li><a href="/wiki/Somatostatin_receptor_4" title="Somatostatin receptor 4">4</a></li> <li><a href="/wiki/Somatostatin_receptor_5" title="Somatostatin receptor 5">5</a>)</li> <li><a href="/wiki/Tachykinin_receptor" title="Tachykinin receptor">Tachykinin</a> (<a href="/wiki/Tachykinin_receptor_1" title="Tachykinin receptor 1">1</a></li> <li><a href="/wiki/Tachykinin_receptor_2" title="Tachykinin receptor 2">2</a></li> <li><a href="/wiki/Tachykinin_receptor_3" title="Tachykinin receptor 3">3</a>)</li> <li><a href="/wiki/Thyrotropin_receptor" title="Thyrotropin receptor">Thyrotropin</a></li> <li><a href="/wiki/Thyrotropin-releasing_hormone_receptor" title="Thyrotropin-releasing hormone receptor">Thyrotropin-releasing hormone</a></li> <li><a href="/wiki/Urotensin-II_receptor" title="Urotensin-II receptor">Urotensin-II</a></li> <li><a href="/wiki/Vasopressin_receptor" title="Vasopressin receptor">Vasopressin</a> (<a href="/wiki/Arginine_vasopressin_receptor_1A" class="mw-redirect" title="Arginine vasopressin receptor 1A">1A</a></li> <li><a href="/wiki/Arginine_vasopressin_receptor_1B" class="mw-redirect" title="Arginine vasopressin receptor 1B">1B</a></li> <li><a href="/wiki/Arginine_vasopressin_receptor_2" class="mw-redirect" title="Arginine vasopressin receptor 2">2</a>)</li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:7em;text-align:left;">Miscellaneous</th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:7em;text-align:left;"><a href="/wiki/Taste_receptor" title="Taste receptor">Taste</a>, bitter</th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><i>TAS2R</i> <ul><li><a href="/wiki/TAS2R1" title="TAS2R1">1</a></li> <li><a href="/wiki/TAS2R3" title="TAS2R3">3</a></li> <li><a href="/wiki/TAS2R4" title="TAS2R4">4</a></li> <li><a href="/wiki/TAS2R5" title="TAS2R5">5</a></li> <li><a href="/wiki/TAS2R7" title="TAS2R7">7</a></li> <li><a href="/wiki/TAS2R8" title="TAS2R8">8</a></li> <li><a href="/wiki/TAS2R9" title="TAS2R9">9</a></li> <li><a href="/wiki/TAS2R10" title="TAS2R10">10</a></li> <li><a href="/wiki/TAS2R13" title="TAS2R13">13</a></li> <li><a href="/wiki/TAS2R14" title="TAS2R14">14</a></li> <li><a href="/wiki/TAS2R16" title="TAS2R16">16</a></li> <li><a href="/wiki/TAS2R19" title="TAS2R19">19</a></li> <li><a href="/wiki/TAS2R20" title="TAS2R20">20</a></li> <li><a href="/wiki/TAS2R30" title="TAS2R30">30</a></li> <li><a href="/wiki/TAS2R31" title="TAS2R31">31</a></li> <li><a href="/wiki/TAS2R38" title="TAS2R38">38</a></li> <li><a href="/wiki/TAS2R39" title="TAS2R39">39</a></li> <li><a href="/wiki/TAS2R40" title="TAS2R40">40</a></li> <li><a href="/wiki/TAS2R41" title="TAS2R41">41</a></li> <li><a href="/wiki/TAS2R42" title="TAS2R42">42</a></li> <li><a href="/wiki/TAS2R43" title="TAS2R43">43</a></li> <li><a href="/wiki/TAS2R45" title="TAS2R45">45</a></li> <li><a href="/wiki/TAS2R46" title="TAS2R46">46</a></li> <li><a href="/wiki/TAS2R50" title="TAS2R50">50</a></li> <li><a href="/wiki/TAS2R60" title="TAS2R60">60</a></li></ul></li> <li><a href="/wiki/Vomeronasal_receptor" title="Vomeronasal receptor">Vomeronasal receptor</a> type 1</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:7em;text-align:left;"><a class="mw-selflink selflink">Orphan</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><i>GPR</i> (<a href="/wiki/GPR1" title="GPR1">1</a></li> <li><a href="/wiki/GPR3" title="GPR3">3</a></li> <li><a href="/wiki/GPR4" title="GPR4">4</a></li> <li><a href="/wiki/GPR6" title="GPR6">6</a></li> <li><a href="/wiki/GPR12" title="GPR12">12</a></li> <li><a href="/wiki/GPR15" title="GPR15">15</a></li> <li><a href="/wiki/GPR17" title="GPR17">17</a></li> <li><a href="/wiki/GPR18" class="mw-redirect" title="GPR18">18</a></li> <li><a href="/wiki/GPR19" title="GPR19">19</a></li> <li><a href="/wiki/GPR20" title="GPR20">20</a></li> <li><a href="/wiki/GPR21" title="GPR21">21</a></li> <li><a href="/wiki/GPR22" title="GPR22">22</a></li> <li><a href="/wiki/LPAR4" title="LPAR4">23</a></li> <li><a href="/wiki/GPR25" title="GPR25">25</a></li> <li><a href="/wiki/GPR26" title="GPR26">26</a></li> <li><a href="/wiki/GPR27" title="GPR27">27</a></li> <li><a href="/wiki/GPR31" title="GPR31">31</a></li> <li><a href="/wiki/GPR32" title="GPR32">32</a></li> <li><a href="/wiki/GPR33" title="GPR33">33</a></li> <li><a href="/wiki/GPR34" title="GPR34">34</a></li> <li><a href="/wiki/GPR35" title="GPR35">35</a></li> <li><a href="/wiki/GPR37" title="GPR37">37</a></li> <li><a href="/wiki/GPR39" title="GPR39">39</a></li> <li><a href="/wiki/GPR42" title="GPR42">42</a></li> <li><a href="/wiki/GPR44" class="mw-redirect" title="GPR44">44</a></li> <li><a href="/wiki/GPR45" title="GPR45">45</a></li> <li><a href="/wiki/GPR50" title="GPR50">50</a></li> <li><a href="/wiki/GPR52" title="GPR52">52</a></li> <li><a href="/wiki/GPR55" title="GPR55">55</a></li> <li><a href="/wiki/GPR61" title="GPR61">61</a></li> <li><a href="/wiki/GPR62" title="GPR62">62</a></li> <li><a href="/wiki/GPR63" title="GPR63">63</a></li> <li><a href="/wiki/GPR65" title="GPR65">65</a></li> <li><a href="/wiki/GPR68" title="GPR68">68</a></li> <li><a href="/wiki/GPR75" title="GPR75">75</a></li> <li><a href="/wiki/GPR78" title="GPR78">78</a></li> <li><a href="/wiki/GPR81" class="mw-redirect" title="GPR81">81</a></li> <li><a href="/wiki/GPR82" title="GPR82">82</a></li> <li><a href="/wiki/GPR83" title="GPR83">83</a></li> <li><a href="/wiki/GPR84" title="GPR84">84</a></li> <li><a href="/wiki/GPR85" title="GPR85">85</a></li> <li><a href="/wiki/GPR87" title="GPR87">87</a></li> <li><a href="/wiki/GPR88" title="GPR88">88</a></li> <li><a href="/wiki/LPAR5" title="LPAR5">92</a></li> <li><a href="/wiki/GPR101" title="GPR101">101</a></li> <li><a href="/wiki/Pyroglutamylated_RFamide_peptide_receptor" title="Pyroglutamylated RFamide peptide receptor">103</a></li> <li><a href="/wiki/Niacin_receptor_1" class="mw-redirect" title="Niacin receptor 1">109A</a></li> <li><a href="/wiki/Niacin_receptor_2" class="mw-redirect" title="Niacin receptor 2">109B</a></li> <li><a href="/wiki/GPR119" title="GPR119">119</a></li> <li><a href="/wiki/GPR120" class="mw-redirect" title="GPR120">120</a></li> <li><a href="/wiki/GPR132" title="GPR132">132</a></li> <li><a href="/wiki/GPR135" title="GPR135">135</a></li> <li><a href="/wiki/GPR137B" title="GPR137B">137B</a></li> <li><a href="/wiki/GPR139" title="GPR139">139</a></li> <li><a href="/wiki/GPR141" title="GPR141">141</a></li> <li><a href="/wiki/GPR142" title="GPR142">142</a></li> <li><a href="/wiki/GPR146" title="GPR146">146</a></li> <li><a href="/wiki/GPR148" title="GPR148">148</a></li> <li><a href="/wiki/GPR149" title="GPR149">149</a></li> <li><a href="/wiki/GPR150" title="GPR150">150</a></li> <li><a href="/wiki/GPR151" title="GPR151">151</a></li> <li><a href="/wiki/GPR152" title="GPR152">152</a></li> <li><a href="/wiki/GPR153" title="GPR153">153</a></li> <li><a href="/wiki/GPR160" title="GPR160">160</a></li> <li><a href="/wiki/GPR161" title="GPR161">161</a></li> <li><a href="/wiki/GPR162" title="GPR162">162</a></li> <li><a href="/wiki/GPR171" title="GPR171">171</a></li> <li><a href="/wiki/GPR173" title="GPR173">173</a></li> <li><a href="/wiki/GPR174" title="GPR174">174</a></li> <li><a href="/wiki/GPR176" title="GPR176">176</a></li> <li><a href="/wiki/GPR177" class="mw-redirect" title="GPR177">177</a></li> <li><a href="/wiki/GPR182" title="GPR182">182</a></li> <li><a href="/wiki/GPR183" title="GPR183">183</a>)</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:7em;text-align:left;"><i>Other</i></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/GPR182" title="GPR182">Adrenomedullin</a></li> <li><a href="/wiki/Olfactory_receptor" title="Olfactory receptor">Olfactory</a></li> <li><a href="/wiki/Opsin" title="Opsin">Opsin</a> (<a href="/wiki/OPN3" title="OPN3">3</a></li> <li><a href="/wiki/Melanopsin" title="Melanopsin">4</a></li> <li><a href="/wiki/OPN5" title="OPN5">5</a></li> <li><a href="/wiki/OPN1LW" title="OPN1LW">1LW</a></li> <li><a href="/wiki/OPN1MW" title="OPN1MW">1MW</a></li> <li><a href="/wiki/OPN1SW" title="OPN1SW">1SW</a></li> <li><a href="/wiki/Retinal_G_protein_coupled_receptor" title="Retinal G protein coupled receptor">RGR</a></li> <li><a href="/wiki/RRH" title="RRH">RRH</a>)</li> <li><a href="/wiki/Protease-activated_receptor" title="Protease-activated receptor">Protease-activated</a> (<a href="/wiki/Coagulation_factor_II_receptor" class="mw-redirect" title="Coagulation factor II receptor">1</a></li> <li><a href="/wiki/Protease_activated_receptor_2" class="mw-redirect" title="Protease activated receptor 2">2</a></li> <li><a href="/wiki/F2RL2" title="F2RL2">3</a></li> <li><a href="/wiki/F2RL3" title="F2RL3">4</a>)</li> <li><a href="/wiki/Super_Conserved_Receptor_Expressed_in_Brain" title="Super Conserved Receptor Expressed in Brain">SREB</a> (<a href="/wiki/GPR27" title="GPR27">1</a></li> <li><a href="/wiki/GPR85" title="GPR85">2</a></li> <li><a href="/wiki/GPR173" title="GPR173">3</a>)</li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks mw-collapsible mw-collapsed navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Class_B:_Secretin-like" style="font-size:114%;margin:0 4em"><a href="/wiki/Secretin_receptor_family" title="Secretin receptor family">Class B</a>: <a href="/wiki/Secretin_receptor" title="Secretin receptor">Secretin</a>-like</div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:10em;text-align:left;"><a href="/wiki/Adhesion_G_protein-coupled_receptor" title="Adhesion G protein-coupled receptor">Adhesion</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><i>ADGRB</i> <ul><li><a href="/wiki/Brain-specific_angiogenesis_inhibitor" title="Brain-specific angiogenesis inhibitor">Brain-specific angiogenesis inhibitor</a> <ul><li><a href="/wiki/Brain-specific_angiogenesis_inhibitor_1" title="Brain-specific angiogenesis inhibitor 1">1</a></li> <li><a href="/wiki/Brain-specific_angiogenesis_inhibitor_2" title="Brain-specific angiogenesis inhibitor 2">2</a></li> <li><a href="/wiki/Brain-specific_angiogenesis_inhibitor_3" title="Brain-specific angiogenesis inhibitor 3">3</a></li></ul></li></ul></li> <li><i>ADGRC</i> <ul><li><a href="/wiki/Flamingo_(protein)" title="Flamingo (protein)">Cadherin</a> <ul><li><a href="/wiki/CELSR1" title="CELSR1">1</a></li> <li><a href="/wiki/CELSR2" title="CELSR2">2</a></li> <li><a href="/wiki/CELSR3" title="CELSR3">3</a></li></ul></li></ul></li> <li><i>ADGRE</i> <ul><li><a href="/wiki/EGF_module-containing_mucin-like_hormone_receptor" title="EGF module-containing mucin-like hormone receptor">EMR</a> <ul><li><a href="/wiki/EMR1" title="EMR1">1</a></li> <li><a href="/wiki/EMR2" title="EMR2">2</a></li> <li><a href="/wiki/EMR3" title="EMR3">3</a></li></ul></li> <li><a href="/wiki/CD97" title="CD97">CD97</a></li></ul></li> <li><i>ADGRG</i> <ul><li><a href="/wiki/GPR56" title="GPR56">1</a></li> <li><a href="/wiki/GPR64" title="GPR64">2</a></li> <li><a href="/wiki/GPR97" title="GPR97">3</a></li> <li><a href="/wiki/GPR112" title="GPR112">4</a></li> <li><a href="/wiki/GPR114" title="GPR114">5</a></li> <li><a href="/wiki/GPR126" title="GPR126">6</a></li> <li><a href="/wiki/GPR128" title="GPR128">7</a></li></ul></li> <li><i>ADGRL</i> <ul><li><a href="/wiki/Latrophilin_receptor" class="mw-redirect" title="Latrophilin receptor">Latrophilin</a> <ul><li><a href="/wiki/Latrophilin_1" title="Latrophilin 1">1</a></li> <li><a href="/wiki/Latrophilin_2" title="Latrophilin 2">2</a></li> <li><a href="/wiki/Latrophilin_3" title="Latrophilin 3">3</a></li></ul></li> <li><a href="/wiki/ELTD1" class="mw-redirect" title="ELTD1">ELTD1</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:10em;text-align:left;"><a class="mw-selflink selflink">Orphan</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><i>GPR</i> (<a href="/wiki/GPR56" title="GPR56">56</a></li> <li><a href="/wiki/GPR64" title="GPR64">64</a></li> <li><a href="/wiki/GPR97" title="GPR97">97</a></li> <li><a href="/wiki/GPR98" title="GPR98">98</a></li> <li><a href="/wiki/GPR110" title="GPR110">110</a></li> <li><a href="/wiki/GPR111" title="GPR111">111</a></li> <li><a href="/wiki/GPR112" title="GPR112">112</a></li> <li><a href="/wiki/GPR113" title="GPR113">113</a></li> <li><a href="/wiki/GPR114" title="GPR114">114</a></li> <li><a href="/wiki/GPR115" title="GPR115">115</a></li> <li><a href="/wiki/GPR116" title="GPR116">116</a></li> <li><a href="/wiki/GPR123" title="GPR123">123</a></li> <li><a href="/wiki/GPR124" title="GPR124">124</a></li> <li><a href="/wiki/GPR125" title="GPR125">125</a></li> <li><a href="/wiki/GPR126" title="GPR126">126</a></li> <li><a href="/wiki/GPR128" title="GPR128">128</a></li> <li><a href="/wiki/GPR133" title="GPR133">133</a></li> <li><a href="/wiki/GPR143" title="GPR143">143</a></li> <li><a href="/wiki/GPR144" title="GPR144">144</a></li> <li><a href="/wiki/GPR155" title="GPR155">155</a></li> <li><a href="/wiki/GPR157" title="GPR157">157</a>)</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:10em;text-align:left;"><i>Other</i></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Calcitonin_receptor" title="Calcitonin receptor">Calcitonin</a></li> <li><a href="/wiki/CALCRL" title="CALCRL">CALCRL</a></li> <li><a href="/wiki/Corticotropin-releasing_hormone_receptor" title="Corticotropin-releasing hormone receptor">Corticotropin-releasing hormone</a> (<a href="/wiki/Corticotropin-releasing_hormone_receptor_1" title="Corticotropin-releasing hormone receptor 1">1</a></li> <li><a href="/wiki/Corticotropin-releasing_hormone_receptor_2" title="Corticotropin-releasing hormone receptor 2">2</a>)</li> <li><a href="/wiki/Glucagon_receptor_family" title="Glucagon receptor family">Glucagon</a> (<a href="/wiki/Glucagon_receptor" title="Glucagon receptor">GR</a></li> <li><a href="/wiki/Gastric_inhibitory_polypeptide_receptor" title="Gastric inhibitory polypeptide receptor">GIPR</a></li> <li><a href="/wiki/Glucagon-like_peptide-1_receptor" title="Glucagon-like peptide-1 receptor">GLP1R</a></li> <li><a href="/wiki/Glucagon-like_peptide-2_receptor" title="Glucagon-like peptide-2 receptor">GLP2R</a>)</li> <li><a href="/wiki/Growth-hormone-releasing_hormone_receptor" title="Growth-hormone-releasing hormone receptor">Growth-hormone-releasing hormone</a></li> <li><a href="/wiki/ADCYAP1R1" title="ADCYAP1R1">PACAPR1</a></li> <li><a class="mw-selflink selflink">GPR</a></li> <li><a href="/wiki/Methuselah-like_proteins" title="Methuselah-like proteins">Methuselah-like proteins</a></li> <li><a href="/wiki/Parathyroid_hormone_receptor" title="Parathyroid hormone receptor">Parathyroid hormone</a> (<a href="/wiki/Parathyroid_hormone_1_receptor" title="Parathyroid hormone 1 receptor">1</a></li> <li><a href="/wiki/Parathyroid_hormone_2_receptor" title="Parathyroid hormone 2 receptor">2</a>)</li> <li><a href="/wiki/Secretin_receptor" title="Secretin receptor">Secretin</a></li> <li><a href="/wiki/Vasoactive_intestinal_peptide_receptor" title="Vasoactive intestinal peptide receptor">Vasoactive intestinal peptide</a> (<a href="/wiki/VIPR1" title="VIPR1">1</a></li> <li><a href="/wiki/VIPR2" title="VIPR2">2</a>)</li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks mw-collapsible mw-collapsed navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Class_C:_Metabotropic_glutamate_/_pheromone" style="font-size:114%;margin:0 4em"><a href="/wiki/Class_C_GPCR" title="Class C GPCR">Class C</a>: <a href="/wiki/Metabotropic_receptor" title="Metabotropic receptor">Metabotropic</a> <a href="/wiki/Metabotropic_glutamate_receptor" title="Metabotropic glutamate receptor">glutamate</a> / <a href="/wiki/Pheromone" title="Pheromone">pheromone</a></div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:10em;text-align:left;"><a href="/wiki/Taste_receptor" title="Taste receptor">Taste</a>, sweet</th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><i>TAS1R</i> <ul><li><a href="/wiki/TAS1R1" title="TAS1R1">1</a></li> <li><a href="/wiki/TAS1R2" title="TAS1R2">2</a></li> <li><a href="/wiki/TAS1R3" title="TAS1R3">3</a></li></ul></li> <li><a href="/wiki/Vomeronasal_receptor" title="Vomeronasal receptor">Vomeronasal receptor</a>, type 2</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:10em;text-align:left;"><i>Other</i></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Calcium-sensing_receptor" title="Calcium-sensing receptor">Calcium-sensing receptor</a></li> <li><a href="/wiki/GABA_receptor" title="GABA receptor">GABA<sub>B</sub></a> (<a href="/wiki/GABBR1" title="GABBR1">1</a></li> <li><a href="/wiki/GABBR2" title="GABBR2">2</a>)</li> <li><a href="/wiki/Glutamate_receptor" title="Glutamate receptor">Glutamate receptor</a> (<a href="/wiki/Metabotropic_glutamate_receptor" title="Metabotropic glutamate receptor">Metabotropic glutamate</a> (<a href="/wiki/Metabotropic_glutamate_receptor_1" title="Metabotropic glutamate receptor 1">1</a></li> <li><a href="/wiki/Metabotropic_glutamate_receptor_2" title="Metabotropic glutamate receptor 2">2</a></li> <li><a href="/wiki/Metabotropic_glutamate_receptor_3" title="Metabotropic glutamate receptor 3">3</a></li> <li><a href="/wiki/Metabotropic_glutamate_receptor_4" title="Metabotropic glutamate receptor 4">4</a></li> <li><a href="/wiki/Metabotropic_glutamate_receptor_5" title="Metabotropic glutamate receptor 5">5</a></li> <li><a href="/wiki/Metabotropic_glutamate_receptor_6" title="Metabotropic glutamate receptor 6">6</a></li> <li><a href="/wiki/Metabotropic_glutamate_receptor_7" title="Metabotropic glutamate receptor 7">7</a></li> <li><a href="/wiki/Metabotropic_glutamate_receptor_8" title="Metabotropic glutamate receptor 8">8</a>))</li> <li><a href="/wiki/GPRC6A" title="GPRC6A">GPRC6A</a></li> <li><a class="mw-selflink selflink">GPR</a> (<a href="/wiki/GPR156" title="GPR156">156</a></li> <li><a href="/wiki/GPR158" title="GPR158">158</a></li> <li><a href="/wiki/GPR179" title="GPR179">179</a>)</li> <li><a href="/wiki/Retinoic_acid-inducible_orphan_G_protein-coupled_receptor" title="Retinoic acid-inducible orphan G protein-coupled receptor">RAIG</a> (<a href="/wiki/GPRC5A" title="GPRC5A">1</a></li> <li><a href="/wiki/GPRC5B" title="GPRC5B">2</a></li> <li><a href="/wiki/GPRC5C" title="GPRC5C">3</a></li> <li><a href="/wiki/GPRC5D" title="GPRC5D">4</a>)</li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks mw-collapsible mw-collapsed navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Class_F:_Frizzled_&amp;_Smoothened" style="font-size:114%;margin:0 4em">Class F: <a href="/wiki/Frizzled" title="Frizzled">Frizzled</a> & <a href="/wiki/Smoothened" title="Smoothened">Smoothened</a></div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:10em;text-align:left;">Frizzled</th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Frizzled" title="Frizzled">Frizzled</a> (<a href="/wiki/FZD1" class="mw-redirect" title="FZD1">1</a></li> <li><a href="/wiki/FZD2" class="mw-redirect" title="FZD2">2</a></li> <li><a href="/wiki/FZD3" class="mw-redirect" title="FZD3">3</a></li> <li><a href="/wiki/FZD4" class="mw-redirect" title="FZD4">4</a></li> <li><a href="/wiki/FZD5" class="mw-redirect" title="FZD5">5</a></li> <li><a href="/wiki/FZD6" class="mw-redirect" title="FZD6">6</a></li> <li><a href="/wiki/FZD7" class="mw-redirect" title="FZD7">7</a></li> <li><a href="/wiki/FZD8" class="mw-redirect" title="FZD8">8</a></li> <li><a href="/wiki/FZD9" class="mw-redirect" title="FZD9">9</a></li> <li><a href="/wiki/FZD10" class="mw-redirect" title="FZD10">10</a>)</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:10em;text-align:left;">Smoothened</th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Smoothened" title="Smoothened">Smoothened</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table></div>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" href="https://en.wikipedia.org/w/index.php?title=Orphan_receptor&oldid=1214805830">https://en.wikipedia.org/w/index.php?title=Orphan_receptor&oldid=1214805830</a>"</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a 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