The nociceptin opioid peptide receptor (NOP), also known as the nociceptin/orphanin FQ (N/OFQ) receptor or kappa-type 3 opioid receptor, is a protein that in humans is encoded by the OPRL1 (opioid receptor-like 1) gene.[5] The nociceptin receptor is a member of the opioid subfamily of G protein-coupled receptors whose natural ligand is the 17 amino acid neuropeptide known as nociceptin (N/OFQ).[6] This receptor is involved in the regulation of numerous brain activities, particularly instinctive and emotional behaviors.[7] Antagonists targeting NOP are under investigation for their role as treatments for depression and Parkinson's disease, whereas NOP agonists have been shown to act as powerful, non-addictive painkillers in non-human primates.
Although NOP shares high sequence identity (~60%) with the ‘classical’ opioid receptors μ-OP (MOP), κ-OP (KOP), and δ-OP (DOP), it possesses little or no affinity for opioid peptides or morphine-like compounds.[8] Likewise, classical opioid receptors possess little affinity towards NOP's endogenous ligand nociceptin, which is structurally related to dynorphin A.[8]
- ^ a b c ENSG00000125510 GRCh38: Ensembl release 89: ENSG00000277044, ENSG00000125510 – Ensembl, May 2017
- ^ a b c GRCm38: Ensembl release 89: ENSMUSG00000027584 – Ensembl, May 2017
- ^ "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
- ^ "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
- ^ Mollereau C, Parmentier M, Mailleux P, Butour JL, Moisand C, Chalon P, et al. (March 1994). "ORL1, a novel member of the opioid receptor family. Cloning, functional expression and localization". FEBS Letters. 341 (1): 33–8. Bibcode:1994FEBSL.341...33M. doi:10.1016/0014-5793(94)80235-1. PMID 8137918. S2CID 25491521.
- ^ Henderson G, McKnight AT (August 1997). "The orphan opioid receptor and its endogenous ligand--nociceptin/orphanin FQ". Trends in Pharmacological Sciences. 18 (8): 293–300. doi:10.1016/S0165-6147(97)90645-3. PMID 9277133.
- ^ "Entrez Gene: OPRL1 opiate receptor-like 1".
- ^ a b Butour JL, Moisand C, Mazarguil H, Mollereau C, Meunier JC (February 1997). "Recognition and activation of the opioid receptor-like ORL 1 receptor by nociceptin, nociceptin analogs and opioids". European Journal of Pharmacology. 321 (1): 97–103. doi:10.1016/S0014-2999(96)00919-3. PMID 9083791.