ID OPRM_RAT Reviewed; 398 AA. AC P33535; Q2TV20; Q2TV21; Q4VWM5; Q4VWM7; Q4VWX7; Q4VWX8; Q62846; AC Q64064; Q64120; DT 01-FEB-1994, integrated into UniProtKB/Swiss-Prot. DT 01-FEB-1994, sequence version 1. DT 13-NOV-2019, entry version 164. DE RecName: Full=Mu-type opioid receptor; DE Short=M-OR-1; DE Short=MOR-1; DE AltName: Full=Opioid receptor B; GN Name=Oprm1; Synonyms=Ror-b; OS Rattus norvegicus (Rat). OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; OC Mammalia; Eutheria; Euarchontoglires; Glires; Rodentia; Myomorpha; OC Muroidea; Muridae; Murinae; Rattus. OX NCBI_TaxID=10116; RN [1] RP NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1). RC TISSUE=Brain; RX PubMed=8394245; DOI=10.1016/0014-5793(93)81011-n; RA Fukuda K., Kato S., Mori K., Nishi M., Takeshima H.; RT "Primary structures and expression from cDNAs of rat opioid receptor RT delta- and mu-subtypes."; RL FEBS Lett. 327:311-314(1993). RN [2] RP NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1). RC TISSUE=Brain; RX PubMed=8234282; DOI=10.1073/pnas.90.21.10230; RA Wang J.-B., Imai Y., Epler M.C., Gregor P., Spivak C., Uhl G.R.; RT "Mu opiate receptor: cDNA cloning and expression."; RL Proc. Natl. Acad. Sci. U.S.A. 90:10230-10234(1993). RN [3] RP NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1), FUNCTION, AND SUBCELLULAR RP LOCATION. RC TISSUE=Brain; RX PubMed=8393525; RA Chen Y., Mestek A., Liu J., Hurley J.A., Yu L.; RT "Molecular cloning and functional expression of a mu-opioid receptor RT from rat brain."; RL Mol. Pharmacol. 44:8-12(1993). RN [4] RP NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1). RC STRAIN=Sprague-Dawley; TISSUE=Brain; RA Bunzow J.R., Grandy D.K., Kelly M.; RL Submitted (SEP-1993) to the EMBL/GenBank/DDBJ databases. RN [5] RP NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1), FUNCTION, AND SUBCELLULAR RP LOCATION. RC STRAIN=Sprague-Dawley; TISSUE=Olfactory bulb; RX PubMed=8240812; DOI=10.1016/0896-6273(93)90120-g; RA Thompson R.C., Mansour A., Akil H., Watson S.J.; RT "Cloning and pharmacological characterization of a rat mu opioid RT receptor."; RL Neuron 11:903-913(1993). RN [6] RP NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1). RC TISSUE=Brain; RX PubMed=8189219; DOI=10.1046/j.1471-4159.1994.62062099.x; RA Zastawny R.L., George S.R., Nguyen T., Cheng R., Tsatsos J., RA Briones-Urbina R., O'Dowd B.F.; RT "Cloning, characterization, and distribution of a mu-opioid receptor RT in rat brain."; RL J. Neurochem. 62:2099-2105(1994). RN [7] RP NUCLEOTIDE SEQUENCE [MRNA] (ISOFORMS 3 AND 5). RC STRAIN=Sprague-Dawley; RA Pan Y.-X., Xu J., Pasternak G.W.; RT "Identification and characterization of two new alternatively spliced RT variants from the rat mu opioid receptor gene, Oprm."; RL Submitted (MAY-2003) to the EMBL/GenBank/DDBJ databases. RN [8] RP NUCLEOTIDE SEQUENCE [MRNA] (ISOFORMS 2; 6; 7 AND 8). RC STRAIN=Sprague-Dawley; RX PubMed=15525342; DOI=10.1111/j.1471-4159.2004.02767.x; RA Pasternak D.A., Pan L., Xu J., Yu R., Xu M.M., Pasternak G.W., RA Pan Y.X.; RT "Identification of three new alternatively spliced variants of the rat RT mu opioid receptor gene: dissociation of affinity and efficacy."; RL J. Neurochem. 91:881-890(2004). RN [9] RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. RC STRAIN=Brown Norway; RX PubMed=15057822; DOI=10.1038/nature02426; RA Gibbs R.A., Weinstock G.M., Metzker M.L., Muzny D.M., Sodergren E.J., RA Scherer S., Scott G., Steffen D., Worley K.C., Burch P.E., Okwuonu G., RA Hines S., Lewis L., Deramo C., Delgado O., Dugan-Rocha S., Miner G., RA Morgan M., Hawes A., Gill R., Holt R.A., Adams M.D., Amanatides P.G., RA Baden-Tillson H., Barnstead M., Chin S., Evans C.A., Ferriera S., RA Fosler C., Glodek A., Gu Z., Jennings D., Kraft C.L., Nguyen T., RA Pfannkoch C.M., Sitter C., Sutton G.G., Venter J.C., Woodage T., RA Smith D., Lee H.-M., Gustafson E., Cahill P., Kana A., RA Doucette-Stamm L., Weinstock K., Fechtel K., Weiss R.B., Dunn D.M., RA Green E.D., Blakesley R.W., Bouffard G.G., De Jong P.J., Osoegawa K., RA Zhu B., Marra M., Schein J., Bosdet I., Fjell C., Jones S., RA Krzywinski M., Mathewson C., Siddiqui A., Wye N., McPherson J., RA Zhao S., Fraser C.M., Shetty J., Shatsman S., Geer K., Chen Y., RA Abramzon S., Nierman W.C., Havlak P.H., Chen R., Durbin K.J., Egan A., RA Ren Y., Song X.-Z., Li B., Liu Y., Qin X., Cawley S., Cooney A.J., RA D'Souza L.M., Martin K., Wu J.Q., Gonzalez-Garay M.L., Jackson A.R., RA Kalafus K.J., McLeod M.P., Milosavljevic A., Virk D., Volkov A., RA Wheeler D.A., Zhang Z., Bailey J.A., Eichler E.E., Tuzun E., RA Birney E., Mongin E., Ureta-Vidal A., Woodwark C., Zdobnov E., RA Bork P., Suyama M., Torrents D., Alexandersson M., Trask B.J., RA Young J.M., Huang H., Wang H., Xing H., Daniels S., Gietzen D., RA Schmidt J., Stevens K., Vitt U., Wingrove J., Camara F., Mar Alba M., RA Abril J.F., Guigo R., Smit A., Dubchak I., Rubin E.M., Couronne O., RA Poliakov A., Huebner N., Ganten D., Goesele C., Hummel O., RA Kreitler T., Lee Y.-A., Monti J., Schulz H., Zimdahl H., RA Himmelbauer H., Lehrach H., Jacob H.J., Bromberg S., RA Gullings-Handley J., Jensen-Seaman M.I., Kwitek A.E., Lazar J., RA Pasko D., Tonellato P.J., Twigger S., Ponting C.P., Duarte J.M., RA Rice S., Goodstadt L., Beatson S.A., Emes R.D., Winter E.E., RA Webber C., Brandt P., Nyakatura G., Adetobi M., Chiaromonte F., RA Elnitski L., Eswara P., Hardison R.C., Hou M., Kolbe D., Makova K., RA Miller W., Nekrutenko A., Riemer C., Schwartz S., Taylor J., Yang S., RA Zhang Y., Lindpaintner K., Andrews T.D., Caccamo M., Clamp M., RA Clarke L., Curwen V., Durbin R.M., Eyras E., Searle S.M., Cooper G.M., RA Batzoglou S., Brudno M., Sidow A., Stone E.A., Payseur B.A., RA Bourque G., Lopez-Otin C., Puente X.S., Chakrabarti K., Chatterji S., RA Dewey C., Pachter L., Bray N., Yap V.B., Caspi A., Tesler G., RA Pevzner P.A., Haussler D., Roskin K.M., Baertsch R., Clawson H., RA Furey T.S., Hinrichs A.S., Karolchik D., Kent W.J., Rosenbloom K.R., RA Trumbower H., Weirauch M., Cooper D.N., Stenson P.D., Ma B., Brent M., RA Arumugam M., Shteynberg D., Copley R.R., Taylor M.S., Riethman H., RA Mudunuri U., Peterson J., Guyer M., Felsenfeld A., Old S., Mockrin S., RA Collins F.S.; RT "Genome sequence of the Brown Norway rat yields insights into RT mammalian evolution."; RL Nature 428:493-521(2004). RN [10] RP NUCLEOTIDE SEQUENCE [MRNA] OF 101-340. RC TISSUE=Macrophage; RX PubMed=7733926; DOI=10.1006/bbrc.1995.1538; RA Sedqi M., Roy S., Ramakrishnan S., Elde R., Loh H.H.; RT "Complementary DNA cloning of a mu-opioid receptor from rat peritoneal RT macrophages."; RL Biochem. Biophys. Res. Commun. 209:563-574(1995). RN [11] RP NUCLEOTIDE SEQUENCE [MRNA] OF 356-398 (ISOFORM 4). RX PubMed=7532594; DOI=10.1016/0014-5793(95)00028-8; RA Zimprich A., Simon T., Hoellt V.; RT "Cloning and expression of an isoform of the rat mu opioid receptor RT (rMOR1B) which differs in agonist induced desensitization from RT rMOR1."; RL FEBS Lett. 359:142-146(1995). RN [12] RP FUNCTION. RX PubMed=1846076; DOI=10.1016/0896-6273(91)90117-i; RA Schroeder J.E., Fischbach P.S., Zheng D., McCleskey E.W.; RT "Activation of mu opioid receptors inhibits transient high- and low- RT threshold Ca2+ currents, but spares a sustained current."; RL Neuron 6:13-20(1991). RN [13] RP FUNCTION. RX PubMed=7678862; DOI=10.1523/jneurosci.13-02-00867.1993; RA Schroeder J.E., McCleskey E.W.; RT "Inhibition of Ca2+ currents by a mu-opioid in a defined subset of rat RT sensory neurons."; RL J. Neurosci. 13:867-873(1993). RN [14] RP FUNCTION, AND MUTAGENESIS OF ASP-114; ASP-147 AND HIS-297. RX PubMed=8051154; RA Surratt C.K., Johnson P.S., Moriwaki A., Seidleck B.K., Blaschak C.J., RA Wang J.B., Uhl G.R.; RT "-mu opiate receptor. Charged transmembrane domain amino acids are RT critical for agonist recognition and intrinsic activity."; RL J. Biol. Chem. 269:20548-20553(1994). RN [15] RP FUNCTION, AND COUPLING TO G-PROTEINS. RX PubMed=7595566; DOI=10.1046/j.1471-4159.1995.65062682.x; RA Chan J.S., Chiu T.T., Wong Y.H.; RT "Activation of type II adenylyl cyclase by the cloned mu-opioid RT receptor: coupling to multiple G proteins."; RL J. Neurochem. 65:2682-2689(1995). RN [16] RP FUNCTION, AND MUTAGENESIS OF ASP-114. RX PubMed=9224819; DOI=10.1124/mol.52.1.105; RA Chakrabarti S., Yang W., Law P.Y., Loh H.H.; RT "The mu-opioid receptor down-regulates differently from the delta- RT opioid receptor: requirement of a high affinity receptor/G protein RT complex formation."; RL Mol. Pharmacol. 52:105-113(1997). RN [17] RP PALMITOYLATION, AND MUTAGENESIS OF CYS-346 AND CYS-351. RX PubMed=9877183; DOI=10.1016/s0014-5793(98)01547-6; RA Chen C., Shahabi V., Xu W., Liu-Chen L.Y.; RT "Palmitoylation of the rat mu opioid receptor."; RL FEBS Lett. 441:148-152(1998). RN [18] RP COUPLING TO GNA15, AND FUNCTION. RX PubMed=9572309; RA Lee J.W., Joshi S., Chan J.S., Wong Y.H.; RT "Differential coupling of mu-, delta-, and kappa-opioid receptors to G RT alpha16-mediated stimulation of phospholipase C."; RL J. Neurochem. 70:2203-2211(1998). RN [19] RP PHOSPHORYLATION, AND MUTAGENESIS OF TYR-91; TYR-96; TYR-166; TYR-336 RP AND THR-394. RX PubMed=10488100; DOI=10.1074/jbc.274.39.27610; RA Pak Y., O'Dowd B.F., Wang J.B., George S.R.; RT "Agonist-induced, G protein-dependent and -independent down-regulation RT of the mu opioid receptor. The receptor is a direct substrate for RT protein-tyrosine kinase."; RL J. Biol. Chem. 274:27610-27616(1999). RN [20] RP PHOSPHORYLATION AT THR-394, AND MUTAGENESIS OF THR-394. RX PubMed=10820022; DOI=10.1021/bi991938b; RA Deng H.B., Yu Y., Pak Y., O'Dowd B.F., George S.R., Surratt C.K., RA Uhl G.R., Wang J.B.; RT "Role for the C-terminus in agonist-induced mu opioid receptor RT phosphorylation and desensitization."; RL Biochemistry 39:5492-5499(2000). RN [21] RP RECEPTOR HETEROOLIGOMERIZATION, AND INTERACTION WITH OPRD1. RX PubMed=10842167; DOI=10.1074/jbc.m000345200; RA George S.R., Fan T., Xie Z., Tse R., Tam V., Varghese G., O'Dowd B.F.; RT "Oligomerization of mu- and delta-opioid receptors. Generation of RT novel functional properties."; RL J. Biol. Chem. 275:26128-26135(2000). RN [22] RP PHOSPHORYLATION BY GRK2. RX PubMed=10744734; DOI=10.1074/jbc.275.14.10443; RA Carman C.V., Barak L.S., Chen C., Liu-Chen L.Y., Onorato J.J., RA Kennedy S.P., Caron M.G., Benovic J.L.; RT "Mutational analysis of Gbetagamma and phospholipid interaction with G RT protein-coupled receptor kinase 2."; RL J. Biol. Chem. 275:10443-10452(2000). RN [23] RP MUTAGENESIS OF ASP-147 AND ASP-164. RX PubMed=11580279; DOI=10.1021/bi0100945; RA Li J., Huang P., Chen C., de Riel J.K., Weinstein H., Liu-Chen L.Y.; RT "Constitutive activation of the mu opioid receptor by mutation of RT D3.49(164), but not D3.32(147): D3.49(164) is critical for RT stabilization of the inactive form of the receptor and for its RT expression."; RL Biochemistry 40:12039-12050(2001). RN [24] RP MUTAGENESIS OF THR-279. RX PubMed=11695897; DOI=10.1021/bi010917q; RA Huang P., Li J., Chen C., Visiers I., Weinstein H., Liu-Chen L.Y.; RT "Functional role of a conserved motif in TM6 of the rat mu opioid RT receptor: constitutively active and inactive receptors result from RT substitutions of Thr6.34(279) with Lys and Asp."; RL Biochemistry 40:13501-13509(2001). RN [25] RP MUTAGENESIS OF THR-180. RX PubMed=11060299; DOI=10.1074/jbc.m007437200; RA Celver J.P., Lowe J., Kovoor A., Gurevich V.V., Chavkin C.; RT "Threonine 180 is required for G-protein-coupled receptor kinase RT 3- and beta-arrestin 2-mediated desensitization of the mu-opioid RT receptor in Xenopus oocytes."; RL J. Biol. Chem. 276:4894-4900(2001). RN [26] RP PHOSPHORYLATION AT SER-363; THR-370 AND SER-375, AND MUTAGENESIS OF RP SER-363; THR-370 AND SER-375. RX PubMed=11278523; DOI=10.1074/jbc.m009571200; RA El Kouhen R., Burd A.L., Erickson-Herbrandson L.J., Chang C.Y., RA Law P.Y., Loh H.H.; RT "Phosphorylation of Ser363, Thr370, and Ser375 residues within the RT carboxyl tail differentially regulates mu-opioid receptor RT internalization."; RL J. Biol. Chem. 276:12774-12780(2001). RN [27] RP MUTAGENESIS OF LEU-275 AND THR-279. RX PubMed=12356297; DOI=10.1021/bi026067b; RA Huang P., Visiers I., Weinstein H., Liu-Chen L.Y.; RT "The local environment at the cytoplasmic end of TM6 of the mu opioid RT receptor differs from those of rhodopsin and monoamine receptors: RT introduction of an ionic lock between the cytoplasmic ends of helices RT 3 and 6 by a L6.30(275)E mutation inactivates the mu opioid receptor RT and reduces the constitutive activity of its T6.34(279)K mutant."; RL Biochemistry 41:11972-11980(2002). RN [28] RP RECEPTOR HETEROOLIGOMERIZATION, AND INTERACTION WITH SSTR2. RX PubMed=11896051; DOI=10.1074/jbc.m110373200; RA Pfeiffer M., Koch T., Schroder H., Laugsch M., Hollt V., Schulz S.; RT "Heterodimerization of somatostatin and opioid receptors cross- RT modulates phosphorylation, internalization, and desensitization."; RL J. Biol. Chem. 277:19762-19772(2002). RN [29] RP INTERACTION WITH PLD2. RX PubMed=12519790; DOI=10.1074/jbc.m206709200; RA Koch T., Brandenburg L.O., Schulz S., Liang Y., Klein J., Hollt V.; RT "ADP-ribosylation factor-dependent phospholipase D2 activation is RT required for agonist-induced mu-opioid receptor endocytosis."; RL J. Biol. Chem. 278:9979-9985(2003). RN [30] RP RECEPTOR HETEROOLIGOMERIZATION, AND INTERACTION WITH ADRA2A. RX PubMed=14645661; DOI=10.1124/mol.64.6.1317; RA Jordan B.A., Gomes I., Rios C., Filipovska J., Devi L.A.; RT "Functional interactions between mu opioid and alpha 2A-adrenergic RT receptors."; RL Mol. Pharmacol. 64:1317-1324(2003). RN [31] RP RECEPTOR HETEROOLIGOMERIZATION, AND INTERACTION WITH CCR5. RX PubMed=14729105; DOI=10.1016/j.ejphar.2003.10.033; RA Chen C., Li J., Bot G., Szabo I., Rogers T.J., Liu-Chen L.Y.; RT "Heterodimerization and cross-desensitization between the mu-opioid RT receptor and the chemokine CCR5 receptor."; RL Eur. J. Pharmacol. 483:175-186(2004). RN [32] RP INTERACTION WITH GNAS. RX PubMed=15857684; DOI=10.1016/j.molbrainres.2004.12.016; RA Chakrabarti S., Regec A., Gintzler A.R.; RT "Biochemical demonstration of mu-opioid receptor association with RT Gsalpha: enhancement following morphine exposure."; RL Brain Res. Mol. Brain Res. 135:217-224(2005). RN [33] RP FUNCTION. RX PubMed=15944153; DOI=10.1074/jbc.m502593200; RA Belcheva M.M., Clark A.L., Haas P.D., Serna J.S., Hahn J.W., Kiss A., RA Coscia C.J.; RT "Mu and kappa opioid receptors activate ERK/MAPK via different protein RT kinase C isoforms and secondary messengers in astrocytes."; RL J. Biol. Chem. 280:27662-27669(2005). RN [34] RP RECEPTOR HETEROOLIGOMERIZATION, AND INTERACTION WITH OPRD1. RX PubMed=17384143; DOI=10.1096/fj.06-7793com; RA Rozenfeld R., Devi L.A.; RT "Receptor heterodimerization leads to a switch in signaling: beta- RT arrestin2-mediated ERK activation by mu-delta opioid receptor RT heterodimers."; RL FASEB J. 21:2455-2465(2007). RN [35] RP INTERACTION WITH GPM6A. RX PubMed=17548356; DOI=10.1074/jbc.m700941200; RA Wu D.F., Koch T., Liang Y.J., Stumm R., Schulz S., Schroder H., RA Hollt V.; RT "Membrane glycoprotein M6a interacts with the micro-opioid receptor RT and facilitates receptor endocytosis and recycling."; RL J. Biol. Chem. 282:22239-22247(2007). RN [36] RP INTERACTION WITH SYP. RX PubMed=17005904; DOI=10.1124/mol.106.026062; RA Liang Y.J., Wu D.F., Yang L.Q., Hollt V., Koch T.; RT "Interaction of the mu-opioid receptor with synaptophysin influences RT receptor trafficking and signaling."; RL Mol. Pharmacol. 71:123-131(2007). RN [37] RP FUNCTION, RECEPTOR HETEROOLIGOMERIZATION, AND INTERACTION WITH CNR1. RX PubMed=16682964; DOI=10.1038/sj.bjp.0706757; RA Rios C., Gomes I., Devi L.A.; RT "mu opioid and CB1 cannabinoid receptor interactions: reciprocal RT inhibition of receptor signaling and neuritogenesis."; RL Br. J. Pharmacol. 148:387-395(2006). RN [38] RP MUTAGENESIS OF SER-363; THR-370 AND SER-375. RX PubMed=18558479; DOI=10.1016/j.cellsig.2008.05.004; RA Chu J., Zheng H., Loh H.H., Law P.Y.; RT "Morphine-induced mu-opioid receptor rapid desensitization is RT independent of receptor phosphorylation and beta-arrestins."; RL Cell. Signal. 20:1616-1624(2008). RN [39] RP FUNCTION. RX PubMed=17947509; DOI=10.1124/mol.107.039842; RA Zheng H., Loh H.H., Law P.Y.; RT "Beta-arrestin-dependent mu-opioid receptor-activated extracellular RT signal-regulated kinases (ERKs) Translocate to Nucleus in Contrast to RT G protein-dependent ERK activation."; RL Mol. Pharmacol. 73:178-190(2008). RN [40] RP INTERACTION WITH RGS4. RX PubMed=19324084; DOI=10.1016/j.cellsig.2009.03.013; RA Leontiadis L.J., Papakonstantinou M.P., Georgoussi Z.; RT "Regulator of G protein signaling 4 confers selectivity to specific G RT proteins to modulate mu- and delta-opioid receptor signaling."; RL Cell. Signal. 21:1218-1228(2009). RN [41] RP PHOSPHORYLATION AT TYR-166, AND MUTAGENESIS OF TYR-166. RX PubMed=19959593; DOI=10.1124/mol.109.060558; RA Clayton C.C., Bruchas M.R., Lee M.L., Chavkin C.; RT "Phosphorylation of the mu-opioid receptor at tyrosine 166 (Tyr3.51) RT in the DRY motif reduces agonist efficacy."; RL Mol. Pharmacol. 77:339-347(2010). RN [42] RP FUNCTION, AND MUTAGENESIS OF SER-375. RX PubMed=21292762; DOI=10.1074/jbc.m110.177089; RA Zheng H., Chu J., Zhang Y., Loh H.H., Law P.Y.; RT "Modulating micro-opioid receptor phosphorylation switches agonist- RT dependent signaling as reflected in PKCepsilon activation and RT dendritic spine stability."; RL J. Biol. Chem. 286:12724-12733(2011). CC -!- FUNCTION: Receptor for endogenous opioids such as beta-endorphin CC and endomorphin. Receptor for natural and synthetic opioids CC including morphine, heroin, DAMGO, fentanyl, etorphine, CC buprenorphin and methadone. Agonist binding to the receptor CC induces coupling to an inactive GDP-bound heterotrimeric G-protein CC complex and subsequent exchange of GDP for GTP in the G-protein CC alpha subunit leading to dissociation of the G-protein complex CC with the free GTP-bound G-protein alpha and the G-protein beta- CC gamma dimer activating downstream cellular effectors. The CC agonist- and cell type-specific activity is predominantly coupled CC to pertussis toxin-sensitive G(i) and G(o) G alpha proteins, CC GNAI1, GNAI2, GNAI3 and GNAO1 isoforms Alpha-1 and Alpha-2, and to CC a lesser extent to pertussis toxin-insensitive G alpha proteins CC GNAZ and GNA15. They mediate an array of downstream cellular CC responses, including inhibition of adenylate cyclase activity and CC both N-type and L-type calcium channels, activation of inward CC rectifying potassium channels, mitogen-activated protein kinase CC (MAPK), phospholipase C (PLC), phosphoinositide/protein kinase CC (PKC), phosphoinositide 3-kinase (PI3K) and regulation of NF- CC kappa-B. Also couples to adenylate cyclase stimulatory G alpha CC proteins. The selective temporal coupling to G-proteins and CC subsequent signaling can be regulated by RGSZ proteins, such as CC RGS9, RGS17 and RGS4. Phosphorylation by members of the GPRK CC subfamily of Ser/Thr protein kinases and association with beta- CC arrestins is involved in short-term receptor desensitization. CC Beta-arrestins associate with the GPRK-phosphorylated receptor and CC uncouple it from the G-protein thus terminating signal CC transduction. The phosphorylated receptor is internalized through CC endocytosis via clathrin-coated pits which involves beta- CC arrestins. The activation of the ERK pathway occurs either in a G- CC protein-dependent or a beta-arrestin-dependent manner and is CC regulated by agonist-specific receptor phosphorylation. Acts as a CC class A G-protein coupled receptor (GPCR) which dissociates from CC beta-arrestin at or near the plasma membrane and undergoes rapid CC recycling. Receptor down-regulation pathways are varying with the CC agonist and occur dependent or independent of G-protein coupling. CC Endogenous ligands induce rapid desensitization, endocytosis and CC recycling. Heterooligomerization with other GPCRs can modulate CC agonist binding, signaling and trafficking properties. Involved in CC neurogenesis. {ECO:0000269|PubMed:15944153, CC ECO:0000269|PubMed:16682964, ECO:0000269|PubMed:17947509, CC ECO:0000269|PubMed:1846076, ECO:0000269|PubMed:21292762, CC ECO:0000269|PubMed:7595566, ECO:0000269|PubMed:7678862, CC ECO:0000269|PubMed:8051154, ECO:0000269|PubMed:8240812, CC ECO:0000269|PubMed:8393525, ECO:0000269|PubMed:9224819, CC ECO:0000269|PubMed:9572309}. CC -!- SUBUNIT: Forms homooligomers and heterooligomers with other GPCRs, CC such as OPRD1, OPRK1, OPRL1, NPFFR2, ADRA2A, SSTR2, CNR1 and CCR5 CC (probably in dimeric forms) (PubMed:10842167, PubMed:11896051, CC PubMed:14645661, PubMed:14729105, PubMed:17384143, CC PubMed:16682964). Interacts with heterotrimeric G proteins; CC interaction with a heterotrimeric complex containing GNAI1, GNB1 CC and GNG2 stabilizes the active conformation of the receptor and CC increases its affinity for endomorphin-2, the synthetic opioid CC peptide DAMGO and for morphinan agonists (By similarity). CC Interacts with PPL; the interaction disrupts agonist-mediated G- CC protein activation. Interacts (via C-terminus) with DNAJB4 (via C- CC terminus). Interacts with calmodulin; the interaction inhibits the CC constitutive activity of OPRM1; it abolishes basal and attenuates CC agonist-stimulated G-protein coupling (By similarity). Interacts CC with FLNA, PLD2, RANBP9 and WLS and GPM6A (PubMed:12519790, CC PubMed:17548356). Interacts with RTP4 (By similarity). Interacts CC with SYP and GNAS (PubMed:15857684, PubMed:17005904). Interacts CC with RGS9, RGS17, RGS20, RGS4, PPP1R9B and HINT1 (By similarity). CC {ECO:0000250|UniProtKB:P35372, ECO:0000250|UniProtKB:P42866, CC ECO:0000269|PubMed:10842167, ECO:0000269|PubMed:11896051, CC ECO:0000269|PubMed:12519790, ECO:0000269|PubMed:14645661, CC ECO:0000269|PubMed:14729105, ECO:0000269|PubMed:15857684, CC ECO:0000269|PubMed:16682964, ECO:0000269|PubMed:17005904, CC ECO:0000269|PubMed:17384143, ECO:0000269|PubMed:17548356, CC ECO:0000269|PubMed:19324084}. CC -!- INTERACTION: CC Q812E9:Gpm6a; NbExp=7; IntAct=EBI-4392569, EBI-6113756; CC P70498:Pld2; NbExp=3; IntAct=EBI-4392569, EBI-6140589; CC P07825:Syp; NbExp=8; IntAct=EBI-4392569, EBI-976085; CC Q6P689:Wls; NbExp=2; IntAct=EBI-4392569, EBI-6113235; CC -!- SUBCELLULAR LOCATION: Cell membrane {ECO:0000269|PubMed:8240812, CC ECO:0000269|PubMed:8393525}; Multi-pass membrane protein CC {ECO:0000250|UniProtKB:P42866}. Cell projection, axon CC {ECO:0000250|UniProtKB:P97266}. Perikaryon CC {ECO:0000250|UniProtKB:P97266}. Cell projection, dendrite CC {ECO:0000250|UniProtKB:P97266}. Endosome CC {ECO:0000250|UniProtKB:P97266}. Note=Is rapidly internalized after CC agonist binding. {ECO:0000250|UniProtKB:P97266}. CC -!- ALTERNATIVE PRODUCTS: CC Event=Alternative splicing; Named isoforms=8; CC Name=1; CC IsoId=P33535-1; Sequence=Displayed; CC Name=2; Synonyms=MOR1A; CC IsoId=P33535-2; Sequence=VSP_041828; CC Name=3; Synonyms=MOR1R; CC IsoId=P33535-3; Sequence=VSP_041829; CC Name=4; Synonyms=MOR1B; CC IsoId=P33535-4; Sequence=VSP_041830; CC Name=5; Synonyms=MOR1B2; CC IsoId=P33535-5; Sequence=VSP_041831; CC Name=6; Synonyms=MOR1C1; CC IsoId=P33535-6; Sequence=VSP_041832; CC Name=7; Synonyms=MOR-1C2; CC IsoId=P33535-7; Sequence=VSP_041833; CC Name=8; Synonyms=rMOR-1D; CC IsoId=P33535-8; Sequence=VSP_041834; CC -!- TISSUE SPECIFICITY: Brain. Is expressed in the cerebral cortex, CC caudate putamen, nucleus accumbens, septal nuclei, thalamus, CC hippocampus, and habenula. Not detected in cerebellum. CC -!- PTM: Phosphorylated. Differentially phosphorylated in basal and CC agonist-induced conditions. Agonist-mediated phosphorylation CC modulates receptor internalization. Phosphorylated by GRK2 in a CC agonist-dependent manner. Phosphorylation at Tyr-166 requires CC receptor activation, is dependent on non-receptor protein tyrosine CC kinase Src and results in a decrease in agonist efficacy by CC reducing G-protein coupling efficiency. Phosphorylated on tyrosine CC residues; the phosphorylation is involved in agonist-induced G- CC protein-independent receptor down-regulation. Phosphorylation at CC Ser-375 is involved in G-protein-dependent but not beta-arrestin- CC dependent activation of the ERK pathway. CC {ECO:0000269|PubMed:10488100, ECO:0000269|PubMed:10744734, CC ECO:0000269|PubMed:10820022, ECO:0000269|PubMed:11278523, CC ECO:0000269|PubMed:19959593}. CC -!- PTM: Ubiquitinated. A basal ubiquitination seems not to be related CC to degradation. Ubiquitination is increased upon formation of CC OPRM1:OPRD1 oligomers leading to proteasomal degradation; the CC ubiquitination is diminished by RTP4. CC {ECO:0000250|UniProtKB:P42866}. CC -!- SIMILARITY: Belongs to the G-protein coupled receptor 1 family. CC {ECO:0000255|PROSITE-ProRule:PRU00521}. CC -!- SEQUENCE CAUTION: CC Sequence=AAQ77387.1; Type=Frameshift; Evidence={ECO:0000305}; CC --------------------------------------------------------------------------- CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms CC Distributed under the Creative Commons Attribution (CC BY 4.0) License CC --------------------------------------------------------------------------- DR EMBL; D16349; BAA03852.1; -; mRNA. DR EMBL; L20684; AAA41643.1; -; mRNA. DR EMBL; L13069; AAA41630.1; -; mRNA. DR EMBL; U02083; AAA70049.1; -; mRNA. DR EMBL; L22455; AAA16075.1; -; mRNA. DR EMBL; U35424; AAA79180.1; -; mRNA. DR EMBL; AY309003; AAQ77387.1; ALT_FRAME; mRNA. DR EMBL; AY309004; AAQ77388.1; -; mRNA. DR EMBL; AY225402; AAP44725.1; -; mRNA. DR EMBL; AY225403; AAP44726.1; -; mRNA. DR EMBL; AY309000; AAQ77384.1; -; mRNA. DR EMBL; AY309002; AAQ77386.1; -; mRNA. DR EMBL; S77863; -; NOT_ANNOTATED_CDS; mRNA. DR EMBL; S75669; AAB33530.2; -; mRNA. DR PIR; I56504; I56504. DR PIR; I56517; I56517. DR PIR; S69010; S69010. DR RefSeq; NP_001033686.1; NM_001038597.2. [P33535-2] DR RefSeq; NP_001033688.2; NM_001038599.2. [P33535-5] DR RefSeq; NP_001033689.1; NM_001038600.2. [P33535-6] DR RefSeq; NP_001033690.1; NM_001038601.2. [P33535-7] DR RefSeq; NP_001291664.1; NM_001304735.1. [P33535-1] DR RefSeq; NP_001291666.1; NM_001304737.1. [P33535-1] DR RefSeq; NP_001291667.1; NM_001304738.1. [P33535-1] DR RefSeq; NP_001291669.1; NM_001304740.1. [P33535-1] DR RefSeq; NP_037203.1; NM_013071.2. [P33535-1] DR SMR; P33535; -. DR BioGrid; 247631; 1. DR CORUM; P33535; -. DR IntAct; P33535; 6. DR STRING; 10116.ENSRNOP00000051290; -. DR BindingDB; P33535; -. DR ChEMBL; CHEMBL270; -. DR DrugCentral; P33535; -. DR GuidetoPHARMACOLOGY; 319; -. DR iPTMnet; P33535; -. DR PhosphoSitePlus; P33535; -. DR SwissPalm; P33535; -. DR PaxDb; P33535; -. DR PRIDE; P33535; -. DR Ensembl; ENSRNOT00000024682; ENSRNOP00000024682; ENSRNOG00000018191. [P33535-6] DR Ensembl; ENSRNOT00000079628; ENSRNOP00000072626; ENSRNOG00000018191. [P33535-8] DR Ensembl; ENSRNOT00000083308; ENSRNOP00000074079; ENSRNOG00000018191. [P33535-1] DR Ensembl; ENSRNOT00000092034; ENSRNOP00000068988; ENSRNOG00000018191. [P33535-7] DR GeneID; 25601; -. DR KEGG; rno:25601; -. DR CTD; 4988; -. DR RGD; 3234; Oprm1. DR eggNOG; KOG3656; Eukaryota. DR eggNOG; ENOG410XRW9; LUCA. DR GeneTree; ENSGT00940000158236; -. DR HOGENOM; HOG000230486; -. DR InParanoid; P33535; -. DR KO; K04215; -. DR OMA; PAWYWEN; -. DR OrthoDB; 1011272at2759; -. DR TreeFam; TF315737; -. DR Reactome; R-RNO-111885; Opioid Signalling. DR Reactome; R-RNO-202040; G-protein activation. DR Reactome; R-RNO-375276; Peptide ligand-binding receptors. DR Reactome; R-RNO-418594; G alpha (i) signalling events. DR PRO; PR:P33535; -. DR Proteomes; UP000002494; Chromosome 1. DR Bgee; ENSRNOG00000018191; Expressed in 1 organ(s), highest expression level in brain. DR ExpressionAtlas; P33535; baseline and differential. DR Genevisible; P33535; RN. DR GO; GO:0030424; C:axon; ISS:UniProtKB. DR GO; GO:0005623; C:cell; IEA:GOC. DR GO; GO:0005737; C:cytoplasm; IDA:RGD. DR GO; GO:0030425; C:dendrite; IDA:RGD. DR GO; GO:0032839; C:dendrite cytoplasm; IDA:RGD. DR GO; GO:0032590; C:dendrite membrane; IDA:RGD. DR GO; GO:0005768; C:endosome; ISS:UniProtKB. DR GO; GO:0005925; C:focal adhesion; IDA:RGD. DR GO; GO:0005887; C:integral component of plasma membrane; IBA:GO_Central. DR GO; GO:0099055; C:integral component of postsynaptic membrane; IDA:SynGO. DR GO; GO:0099056; C:integral component of presynaptic membrane; IDA:SynGO. DR GO; GO:0016020; C:membrane; IDA:RGD. DR GO; GO:0045121; C:membrane raft; IDA:RGD. DR GO; GO:0043204; C:perikaryon; IDA:RGD. DR GO; GO:0097444; C:spine apparatus; IDA:SynGO. DR GO; GO:0004979; F:beta-endorphin receptor activity; IBA:GO_Central. DR GO; GO:0031005; F:filamin binding; IMP:RGD. DR GO; GO:0004930; F:G protein-coupled receptor activity; IDA:RGD. DR GO; GO:0001965; F:G-protein alpha-subunit binding; ISS:UniProtKB. DR GO; GO:0031681; F:G-protein beta-subunit binding; IPI:RGD. DR GO; GO:0038047; F:morphine receptor activity; IDA:RGD. DR GO; GO:0042923; F:neuropeptide binding; IBA:GO_Central. DR GO; GO:0042277; F:peptide binding; IBA:GO_Central. DR GO; GO:0008022; F:protein C-terminus binding; IPI:RGD. DR GO; GO:0019904; F:protein domain specific binding; IPI:RGD. DR GO; GO:0005245; F:voltage-gated calcium channel activity; IMP:UniProtKB. DR GO; GO:0002438; P:acute inflammatory response to antigenic stimulus; IEP:RGD. DR GO; GO:0007191; P:adenylate cyclase-activating dopamine receptor signaling pathway; IEA:Ensembl. DR GO; GO:0007197; P:adenylate cyclase-inhibiting G protein-coupled acetylcholine receptor signaling pathway; IDA:GO_Central. DR GO; GO:0007193; P:adenylate cyclase-inhibiting G protein-coupled receptor signaling pathway; IDA:RGD. DR GO; GO:0031635; P:adenylate cyclase-inhibiting opioid receptor signaling pathway; IDA:RGD. DR GO; GO:0048149; P:behavioral response to ethanol; IEA:Ensembl. DR GO; GO:0042755; P:eating behavior; IMP:RGD. DR GO; GO:0044849; P:estrous cycle; IEP:RGD. DR GO; GO:0060079; P:excitatory postsynaptic potential; IDA:RGD. DR GO; GO:0007186; P:G protein-coupled receptor signaling pathway; IDA:RGD. DR GO; GO:0006955; P:immune response; TAS:RGD. DR GO; GO:0007626; P:locomotory behavior; IEA:Ensembl. DR GO; GO:0106072; P:negative regulation of adenylate cyclase-activating G protein-coupled receptor signaling pathway; IDA:RGD. DR GO; GO:0043951; P:negative regulation of cAMP-mediated signaling; ISS:UniProtKB. DR GO; GO:0051481; P:negative regulation of cytosolic calcium ion concentration; ISS:UniProtKB. DR GO; GO:0045019; P:negative regulation of nitric oxide biosynthetic process; ISS:UniProtKB. DR GO; GO:0061358; P:negative regulation of Wnt protein secretion; ISS:UniProtKB. DR GO; GO:0007218; P:neuropeptide signaling pathway; IBA:GO_Central. DR GO; GO:0038003; P:opioid receptor signaling pathway; IDA:RGD. DR GO; GO:0007200; P:phospholipase C-activating G protein-coupled receptor signaling pathway; IDA:UniProtKB. DR GO; GO:0032100; P:positive regulation of appetite; IMP:RGD. DR GO; GO:0070374; P:positive regulation of ERK1 and ERK2 cascade; IDA:UniProtKB. DR GO; GO:0050769; P:positive regulation of neurogenesis; ISS:UniProtKB. DR GO; GO:0080135; P:regulation of cellular response to stress; IEA:Ensembl. DR GO; GO:2000310; P:regulation of NMDA receptor activity; IMP:UniProtKB. DR GO; GO:0051930; P:regulation of sensory perception of pain; IDA:RGD. DR GO; GO:0042220; P:response to cocaine; IEP:RGD. DR GO; GO:0045471; P:response to ethanol; IDA:RGD. DR GO; GO:0032094; P:response to food; IEP:RGD. DR GO; GO:0070848; P:response to growth factor; IEP:RGD. DR GO; GO:0032496; P:response to lipopolysaccharide; IEP:RGD. DR GO; GO:0043278; P:response to morphine; IEP:RGD. DR GO; GO:0009314; P:response to radiation; IEP:RGD. DR GO; GO:0019233; P:sensory perception of pain; ISS:UniProtKB. DR GO; GO:0042060; P:wound healing; IEP:RGD. DR InterPro; IPR000276; GPCR_Rhodpsn. DR InterPro; IPR017452; GPCR_Rhodpsn_7TM. DR InterPro; IPR000105; Mu_opioid_rcpt. DR InterPro; IPR001418; Opioid_rcpt. DR Pfam; PF00001; 7tm_1; 1. DR PRINTS; PR00237; GPCRRHODOPSN. DR PRINTS; PR00537; MUOPIOIDR. DR PRINTS; PR00384; OPIOIDR. DR PROSITE; PS00237; G_PROTEIN_RECEP_F1_1; 1. DR PROSITE; PS50262; G_PROTEIN_RECEP_F1_2; 1. PE 1: Evidence at protein level; KW Alternative splicing; Cell membrane; Cell projection; KW Complete proteome; Disulfide bond; Endosome; KW G-protein coupled receptor; Glycoprotein; Lipoprotein; Membrane; KW Palmitate; Phosphoprotein; Receptor; Reference proteome; Transducer; KW Transmembrane; Transmembrane helix; Ubl conjugation. FT CHAIN 1 398 Mu-type opioid receptor. FT /FTId=PRO_0000069978. FT TOPO_DOM 1 66 Extracellular. FT {ECO:0000250|UniProtKB:P42866}. FT TRANSMEM 67 91 Helical; Name=1. FT {ECO:0000250|UniProtKB:P42866}. FT TOPO_DOM 92 104 Cytoplasmic. FT {ECO:0000250|UniProtKB:P42866}. FT TRANSMEM 105 129 Helical; Name=2. FT {ECO:0000250|UniProtKB:P42866}. FT TOPO_DOM 130 140 Extracellular. FT {ECO:0000250|UniProtKB:P42866}. FT TRANSMEM 141 163 Helical; Name=3. FT {ECO:0000250|UniProtKB:P42866}. FT TOPO_DOM 164 183 Cytoplasmic. FT {ECO:0000250|UniProtKB:P42866}. FT TRANSMEM 184 205 Helical; Name=4. FT {ECO:0000250|UniProtKB:P42866}. FT TOPO_DOM 206 228 Extracellular. FT {ECO:0000250|UniProtKB:P42866}. FT TRANSMEM 229 253 Helical; Name=5. FT {ECO:0000250|UniProtKB:P42866}. FT TOPO_DOM 254 277 Cytoplasmic. FT {ECO:0000250|UniProtKB:P42866}. FT TRANSMEM 278 304 Helical; Name=6. FT {ECO:0000250|UniProtKB:P42866}. FT TOPO_DOM 305 312 Extracellular. FT {ECO:0000250|UniProtKB:P42866}. FT TRANSMEM 313 336 Helical; Name=7. FT {ECO:0000250|UniProtKB:P42866}. FT TOPO_DOM 337 398 Cytoplasmic. FT {ECO:0000250|UniProtKB:P42866}. FT MOTIF 332 336 NPxxY; plays a role in stabilizing the FT activated conformation of the receptor. FT {ECO:0000250|UniProtKB:P42866}. FT MOD_RES 166 166 Phosphotyrosine. FT {ECO:0000269|PubMed:19959593}. FT MOD_RES 363 363 Phosphoserine. FT {ECO:0000269|PubMed:11278523}. FT MOD_RES 370 370 Phosphothreonine. FT {ECO:0000269|PubMed:11278523}. FT MOD_RES 375 375 Phosphoserine. FT {ECO:0000269|PubMed:11278523}. FT MOD_RES 394 394 Phosphothreonine. FT {ECO:0000305|PubMed:10820022}. FT LIPID 351 351 S-palmitoyl cysteine. {ECO:0000255}. FT CARBOHYD 9 9 N-linked (GlcNAc...) asparagine. FT {ECO:0000255}. FT CARBOHYD 31 31 N-linked (GlcNAc...) asparagine. FT {ECO:0000255}. FT CARBOHYD 38 38 N-linked (GlcNAc...) asparagine. FT {ECO:0000255}. FT CARBOHYD 46 46 N-linked (GlcNAc...) asparagine. FT {ECO:0000255}. FT CARBOHYD 53 53 N-linked (GlcNAc...) asparagine. FT {ECO:0000255}. FT DISULFID 140 217 {ECO:0000255|PROSITE-ProRule:PRU00521}. FT VAR_SEQ 387 398 LENLEAETAPLP -> VCAF (in isoform 2). FT {ECO:0000303|PubMed:15525342}. FT /FTId=VSP_041828. FT VAR_SEQ 387 398 LENLEAETAPLP -> GAEL (in isoform 3). FT {ECO:0000303|Ref.7}. FT /FTId=VSP_041829. FT VAR_SEQ 387 398 LENLEAETAPLP -> KIVLF (in isoform 4). FT {ECO:0000303|PubMed:7532594}. FT /FTId=VSP_041830. FT VAR_SEQ 387 398 LENLEAETAPLP -> EPQSVET (in isoform 5). FT {ECO:0000303|Ref.7}. FT /FTId=VSP_041831. FT VAR_SEQ 387 398 LENLEAETAPLP -> PALAVSVAQIFTGYPSPTHGEKPCK FT SYRDRPRPCGRTWSLKSRAESNVEHFHCGAALIYNNVNFI FT (in isoform 6). FT {ECO:0000303|PubMed:15525342}. FT /FTId=VSP_041832. FT VAR_SEQ 387 398 LENLEAETAPLP -> PALAVSVAQIFTGYPSPTHGEKPCK FT SYRDRPRPCGRTWSLKSRAESNVEHFHCGAALIYNNELKIG FT PVSWLQMPAHVLVRPW (in isoform 7). FT {ECO:0000303|PubMed:15525342}. FT /FTId=VSP_041833. FT VAR_SEQ 387 398 LENLEAETAPLP -> T (in isoform 8). FT {ECO:0000303|PubMed:15525342}. FT /FTId=VSP_041834. FT MUTAGEN 91 91 Y->A: Abolishes agonist-induced G- FT protein-independent receptor FT internalization; when associated with A- FT 96, A-166 and A-336. FT {ECO:0000269|PubMed:10488100}. FT MUTAGEN 96 96 Y->A: Abolishes agonist-induced G- FT protein-independent receptor FT internalization; when associated with A- FT 91, A-166 and A-336. FT {ECO:0000269|PubMed:10488100}. FT MUTAGEN 114 114 D->A,N: Impairs agonist affinity, FT agonist-induced inhibition of adenylate FT cyclase and coupling to G-proteins. FT {ECO:0000269|PubMed:8051154, FT ECO:0000269|PubMed:9224819}. FT MUTAGEN 114 114 D->E: No effect on inhibition of FT adenylate cyclase. FT {ECO:0000269|PubMed:8051154, FT ECO:0000269|PubMed:9224819}. FT MUTAGEN 147 147 D->A: No effect on constitutive FT activation. Impairs agonist affinity and FT agonist-induced inhibition of adenylate FT cyclase. {ECO:0000269|PubMed:11580279, FT ECO:0000269|PubMed:8051154}. FT MUTAGEN 147 147 D->E: Impairs agonist affinity and FT increases agonist-induced inhibition of FT adenylate cyclase. FT {ECO:0000269|PubMed:11580279, FT ECO:0000269|PubMed:8051154}. FT MUTAGEN 147 147 D->N: No effect on constitutive FT activation. {ECO:0000269|PubMed:11580279, FT ECO:0000269|PubMed:8051154}. FT MUTAGEN 164 164 D->E: Reduces basal activity. FT {ECO:0000269|PubMed:11580279}. FT MUTAGEN 164 164 D->H,M,Q,Y: Constitutive active. FT {ECO:0000269|PubMed:11580279}. FT MUTAGEN 166 166 Y->A: Abolishes agonist-induced G- FT protein-independent receptor FT internalization; when associated with A- FT 91, A-96 and A-336. FT {ECO:0000269|PubMed:10488100, FT ECO:0000269|PubMed:19959593}. FT MUTAGEN 166 166 Y->F: Decrease in phosphorylation, no FT decrease in G-protein binding. FT {ECO:0000269|PubMed:10488100, FT ECO:0000269|PubMed:19959593}. FT MUTAGEN 180 180 T->A: Impairs ARRB2- and GRK3-mediated FT receptor desensitization. FT {ECO:0000269|PubMed:11060299}. FT MUTAGEN 275 275 L->E: No effect on constitutive FT activation. Some constitutive activity; FT when associated with K-279. FT {ECO:0000269|PubMed:12356297}. FT MUTAGEN 279 279 T->D: Receptor inactivation. FT {ECO:0000269|PubMed:11695897, FT ECO:0000269|PubMed:12356297}. FT MUTAGEN 279 279 T->K: Constitutive active. Some FT constitutive activity; when associated FT with E-275. {ECO:0000269|PubMed:11695897, FT ECO:0000269|PubMed:12356297}. FT MUTAGEN 297 297 H->A: Impairs agonist affinity and FT increases agonist-induced inhibition of FT adenylate cyclase. FT {ECO:0000269|PubMed:8051154}. FT MUTAGEN 336 336 Y->A: Abolishes agonist-induced G- FT protein-independent receptor FT internalization; when associated with A- FT 91, A-96 and A-166. FT {ECO:0000269|PubMed:10488100}. FT MUTAGEN 346 346 C->A: No change in palmitoylation. No FT change in palmitoylation; when associated FT with A-351. {ECO:0000269|PubMed:9877183}. FT MUTAGEN 351 351 C->A: No change in palmitoylation; when FT associated with A-346. FT {ECO:0000269|PubMed:9877183}. FT MUTAGEN 363 363 S->A: Abolishes basal phosphorylation; FT when associated with A-370. Abolishes FT basal and agonist-induced FT phosphorylation; when associated with A- FT 370 and A-375. Accelerates agonist- FT induced receptor internalization. FT {ECO:0000269|PubMed:11278523, FT ECO:0000269|PubMed:18558479}. FT MUTAGEN 370 370 T->A: Abolishes basal phosphorylation; FT when associated with A-363. Abolishes FT basal and agonist-induced FT phosphorylation; when associated with A- FT 363 and A-375. Accelerates agonist- FT induced receptor internalization. FT {ECO:0000269|PubMed:11278523, FT ECO:0000269|PubMed:18558479}. FT MUTAGEN 375 375 S->A: Reduces agonist-induced receptor FT internalization. Abolishes morphine- FT induced phosphorylation. Restores FT agonist-specific PRKCE activity. FT Abolishes basal and agonist-induced FT phosphorylation; when associated with A- FT 363 and A-370. FT {ECO:0000269|PubMed:11278523, FT ECO:0000269|PubMed:18558479, FT ECO:0000269|PubMed:21292762}. FT MUTAGEN 394 394 T->A: Impairs phosphorylation and FT abolishes agonist-mediated acute receptor FT desensitization. FT {ECO:0000269|PubMed:10488100, FT ECO:0000269|PubMed:10820022}. FT CONFLICT 237 237 F -> G (in Ref. 6; AAA79180). FT {ECO:0000305}. FT CONFLICT 238 238 I -> V (in Ref. 7; AAQ77386). FT {ECO:0000305}. FT CONFLICT 245 245 V -> I (in Ref. 3; AAA41630, 4; AAA70049 FT and 10; S77863). {ECO:0000305}. SQ SEQUENCE 398 AA; 44494 MW; 9C916DE7C1C33743 CRC64; MDSSTGPGNT SDCSDPLAQA SCSPAPGSWL NLSHVDGNQS DPCGLNRTGL GGNDSLCPQT GSPSMVTAIT IMALYSIVCV VGLFGNFLVM YVIVRYTKMK TATNIYIFNL ALADALATST LPFQSVNYLM GTWPFGTILC KIVISIDYYN MFTSIFTLCT MSVDRYIAVC HPVKALDFRT PRNAKIVNVC NWILSSAIGL PVMFMATTKY RQGSIDCTLT FSHPTWYWEN LLKICVFIFA FIMPVLIITV CYGLMILRLK SVRMLSGSKE KDRNLRRITR MVLVVVAVFI VCWTPIHIYV IIKALITIPE TTFQTVSWHF CIALGYTNSC LNPVLYAFLD ENFKRCFREF CIPTSSTIEQ QNSTRVRQNT REHPSTANTV DRTNHQLENL EAETAPLP //