cDNA Cloning of an orphan opiate receptor gene family member and its splice variant

Abstract

Radioligand binding and cDNA homology studies have suggested the existence of opiate receptors distinct from the recently-cloned p, S and K receptors. XORlS, a rat brain cDNA whose predicted translation product displays 67-72% homology with those encoded by ~1, 61 and ~1 opiate receptor cDNAs, was constructed from two partial cDNAs identified through cDNA homology approaches. A longer XORlL variant of this cDNA was also identified by polymerase chain reaction studies using genomic DNA and cDNA from brain and peripheral tissues. XORl mRNA is most highly expressed in hypothalamus. COS cell expression of both clones confers neither robust binding of opiate hgands nor reproducible opiate inhibition of forskolin-stimulated adenylate cyclase. These studies identify an orphan clone that helps to define features of the opiate receptor gene family, including apparent differential splicing and expression in peripheral tissues.

Comparison of the effects of [Phe1Ψ(CH2‐NH)Gly2]Nociceptin (1–13)NH2 in rat brain, rat vas deferens and CHO cells expressing recombinant human nociceptin receptors

“…The transcript encoding the NC-receptor is found not only in the central nervous system (Darland & Grandy, 1998) but also in peripheral tissues such as rat intestine, skeletal muscle, vas deferens, spleen and lymphocytes (Wang et al, 1994;Peluso et al, 1998;Wick et al, 1995). NC is reported to inhibit electrically induced contractions in several peripheral isolated preparations (see for review).…”

Functional expression, activation and desensitization of opioid receptor‐like receptor ORL1 in neuroblastoma×glioma NG108‐15 hybrid cells

“…These opioid receptors are all coupled to the inhibitory G protein (Gi) and negatively regulate adenylyl cyclase [1]. Recently, another Gi protein coupled receptor, opioid receptor-like receptor (ORLi), has been cloned from brain [2][3][4][5][6][7][8]. Its endogenous specific agonist nociceptin/orphanin FQ (OFQ) has also been identified [9,10].…”

Association of aminopeptidase N and endopeptidase 24.15 inhibitors potentiate behavioral effects mediated by nociceptin/orphanin FQ in mice

“…In addition to the three major types of opioid receptors, μ, δ and κ (review in [1]), a novel receptor (ORLi, opioid receptor-likei) was identified on the basis of its homology with the amino acid sequence of opioid receptors [2][3][4][5][6][7][8]. The ORLi receptor has a very low affinity for traditional opioid peptides (dynorphins, endorphins, and enkephalins).…”