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NameMu-type opioid receptor
Synonyms
  • hMOP
  • M-OR-1
  • MOP
  • MOR1
  • Mu opiate receptor
  • Mu opioid receptor
Gene NameOPRM1
OrganismHuman
Amino acid sequence
>lcl|BSEQ0001536|Mu-type opioid receptor
MDSSAAPTNASNCTDALAYSSCSPAPSPGSWVNLSHLDGNLSDPCGPNRTDLGGRDSLCP
PTGSPSMITAITIMALYSIVCVVGLFGNFLVMYVIVRYTKMKTATNIYIFNLALADALAT
STLPFQSVNYLMGTWPFGTILCKIVISIDYYNMFTSIFTLCTMSVDRYIAVCHPVKALDF
RTPRNAKIINVCNWILSSAIGLPVMFMATTKYRQGSIDCTLTFSHPTWYWENLLKICVFI
FAFIMPVLIITVCYGLMILRLKSVRMLSGSKEKDRNLRRITRMVLVVVAVFIVCWTPIHI
YVIIKALVTIPETTFQTVSWHFCIALGYTNSCLNPVLYAFLDENFKRCFREFCIPTSSNI
EQQNSTRIRQNTRDHPSTANTVDRTNHQLENLEAETAPLP
Number of residues400
Molecular Weight44778.855
Theoretical pI8.29
GO Classification
Functions
  • neuropeptide binding
  • G-protein alpha-subunit binding
  • G-protein beta-subunit binding
  • voltage-gated calcium channel activity
  • G-protein coupled receptor activity
  • beta-endorphin receptor activity
  • morphine receptor activity
Processes
  • behavioral response to ethanol
  • positive regulation of cytosolic calcium ion concentration
  • opioid receptor signaling pathway
  • negative regulation of cell proliferation
  • positive regulation of nitric oxide biosynthetic process
  • phospholipase C-activating G-protein coupled receptor signaling pathway
  • regulation of N-methyl-D-aspartate selective glutamate receptor activity
  • locomotory behavior
  • G-protein coupled receptor signaling pathway, coupled to cyclic nucleotide second messenger
  • negative regulation of nitric oxide biosynthetic process
  • sensory perception of pain
  • positive regulation of neurogenesis
  • adenylate cyclase-inhibiting G-protein coupled receptor signaling pathway
  • negative regulation of cAMP-mediated signaling
  • calcium ion transmembrane transport
  • cellular response to stress
  • adenylate cyclase-activating dopamine receptor signaling pathway
  • negative regulation of adenylate cyclase activity
  • neuropeptide signaling pathway
  • positive regulation of ERK1 and ERK2 cascade
  • synaptic transmission
  • cellular response to morphine
  • negative regulation of Wnt protein secretion
  • positive regulation of cAMP-mediated signaling
  • sensory perception
  • negative regulation of cytosolic calcium ion concentration
Components
  • cytosol
  • integral component of plasma membrane
  • neuron projection
  • endoplasmic reticulum
  • plasma membrane
  • Golgi apparatus
General FunctionVoltage-gated calcium channel activity
Specific FunctionReceptor for endogenous opioids such as beta-endorphin and endomorphin. Receptor for natural and synthetic opioids including morphine, heroin, DAMGO, fentanyl, etorphine, buprenorphin and methadone. Agonist binding to the receptor induces coupling to an inactive GDP-bound heterotrimeric G-protein complex and subsequent exchange of GDP for GTP in the G-protein alpha subunit leading to dissociation of the G-protein complex with the free GTP-bound G-protein alpha and the G-protein beta-gamma dimer activating downstream cellular effectors. The agonist- and cell type-specific activity is predominantly coupled to pertussis toxin-sensitive G(i) and G(o) G alpha proteins, GNAI1, GNAI2, GNAI3 and GNAO1 isoforms Alpha-1 and Alpha-2, and to a lesser extend to pertussis toxin-insensitive G alpha proteins GNAZ and GNA15. They mediate an array of downstream cellular responses, including inhibition of adenylate cyclase activity and both N-type and L-type calcium channels, activation of inward rectifying potassium channels, mitogen-activated protein kinase (MAPK), phospholipase C (PLC), phosphoinositide/protein kinase (PKC), phosphoinositide 3-kinase (PI3K) and regulation of NF-kappa-B. Also couples to adenylate cyclase stimulatory G alpha proteins. The selective temporal coupling to G-proteins and subsequent signaling can be regulated by RGSZ proteins, such as RGS9, RGS17 and RGS4. Phosphorylation by members of the GPRK subfamily of Ser/Thr protein kinases and association with beta-arrestins is involved in short-term receptor desensitization. Beta-arrestins associate with the GPRK-phosphorylated receptor and uncouple it from the G-protein thus terminating signal transduction. The phosphorylated receptor is internalized through endocytosis via clathrin-coated pits which involves beta-arrestins. The activation of the ERK pathway occurs either in a G-protein-dependent or a beta-arrestin-dependent manner and is regulated by agonist-specific receptor phosphorylation. Acts as a class A G-protein coupled receptor (GPCR) which dissociates from beta-arrestin at or near the plasma membrane and undergoes rapid recycling. Receptor down-regulation pathways are varying with the agonist and occur dependent or independent of G-protein coupling. Endogenous ligands induce rapid desensitization, endocytosis and recycling whereas morphine induces only low desensitization and endocytosis. Heterooligomerization with other GPCRs can modulate agonist binding, signaling and trafficking properties. Involved in neurogenesis. Isoform 12 couples to GNAS and is proposed to be involved in excitatory effects. Isoform 16 and isoform 17 do not bind agonists but may act through oligomerization with binding-competent OPRM1 isoforms and reduce their ligand binding activity.
Pfam Domain Function
Transmembrane Regions69-93 107-131 143-165 186-207 231-255 284-307 315-338
GenBank Protein ID452073
UniProtKB IDP35372
UniProtKB Entry NameOPRM_HUMAN
Cellular LocationCell membrane
Gene sequence
>lcl|BSEQ0021649|Mu-type opioid receptor (OPRM1)
ATGGACAGCAGCGCTGCCCCCACGAACGCCAGCAATTGCACTGATGCCTTGGCGTACTCA
AGTTGCTCCCCAGCACCCAGCCCCGGTTCCTGGGTCAACTTGTCCCACTTAGATGGCAAC
CTGTCCGACCCATGCGGTCCGAACCGCACCGACCTGGGCGGGAGAGACAGCCTGTGCCCT
CCGACCGGCAGTCCCTCCATGATCACGGCCATCACGATCATGGCCCTCTACTCCATCGTG
TGCGTGGTGGGGCTCTTCGGAAACTTCCTGGTCATGTATGTGATTGTCAGATACACCAAG
ATGAAGACTGCCACCAACATCTACATTTTCAACCTTGCTCTGGCAGATGCCTTAGCCACC
AGTACCCTGCCCTTCCAGAGTGTGAATTACCTAATGGGAACATGGCCATTTGGAACCATC
CTTTGCAAGATAGTGATCTCCATAGATTACTATAACATGTTCACCAGCATATTCACCCTC
TGCACCATGAGTGTTGATCGATACATTGCAGTCTGCCACCCTGTCAAGGCCTTAGATTTC
CGTACTCCCCGAAATGCCAAAATTATCAATGTCTGCAACTGGATCCTCTCTTCAGCCATT
GGTCTTCCTGTAATGTTCATGGCTACAACAAAATACAGGCAAGGTTCCATAGATTGTACA
CTAACATTCTCTCATCCAACCTGGTACTGGGAAAACCTGCTGAAGATCTGTGTTTTCATC
TTCGCCTTCATTATGCCAGTGCTCATCATTACCGTGTGCTATGGACTGATGATCTTGCGC
CTCAAGAGTGTCCGCATGCTCTCTGGCTCCAAAGAAAAGGACAGGAATCTTCGAAGGATC
ACCAGGATGGTGCTGGTGGTGGTGGCTGTGTTCATCGTCTGCTGGACTCCCATTCACATT
TACGTCATCATTAAAGCCTTGGTTACAATCCCAGAAACTACGTTCCAGACTGTTTCTTGG
CACTTCTGCATTGCTCTAGGTTACACAAACAGCTGCCTCAACCCAGTCCTTTATGCATTT
CTGGATGAAAACTTCAAACGATGCTTCAGAGAGTTCTGTATCCCAACCTCTTCCAACATT
GAGCAACAAAACTCCACTCGAATTCGTCAGAACACTAGAGACCACCCCTCCACGGCCAAT
ACAGTGGATAGAACTAATCATCAGCTAGAAAATCTGGAAGCAGAAACTGCTCCGTTGCCC
TAA
GenBank Gene IDL25119
GeneCard IDNot Available
GenAtlas IDOPRM1
HGNC IDHGNC:8156
Chromosome Location6
Locus6q24-q25
References
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