Characterization of ZFOR1, a putative delta-opioid receptor from the teleost zebrafish (Danio rerio).
ZFOR1 is a putative opioid receptor from zebrafish brain which has 66% homology with the mammalian delta-opioid receptor. When expressed in HEK293 cells ZFOR1 bound the non-selective opioid antagonist [(3)H]diprenorphine with high affinity. However, the binding of this ligand was not readily displaced by opioids selective for mu, delta or kappa opioid receptors (affinities>1000 nM). Rather non-selective ligands showed good affinity, as did the non-peptide delta-ligand BW373U86 (Ki 69 nM), the delta-antagonist naltrindole (Ki 28 nM) and the peptide beta-endorphin (Ki 37 nM). Agonist binding to the receptor encoded by ZFOR1 receptor stimulated the binding of [(35)S]GTPgammaS confirming coupling to G proteins. Study of the receptor should contribute to understanding of the evolution of the opioid system.
Rodriguez
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RE
Instituto de Neurociencias de Castilla y Leon, University of Salamanca, Avenue Alfonso X EL Sabio, 37007, Salamanca, Spain. requelmi@gugu.usal.es
Barrallo
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A
Garcia-Malvar
F
F
McFadyen
I J
IJ
Gonzalez-Sarmiento
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R
Traynor
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JR
D000818:Animals; D001665:Binding Sites / Q000187:drug effects; D004174:Diprenorphine / Q000494:pharmacology; D006801:Humans; D009292:Narcotic Antagonists / Q000494:pharmacology; D017465:Receptors, Opioid, delta / Q000096:biosynthesis / Q000737:chemistry* / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014316:Tritium; D015027:Zebrafish / Q000378:metabolism* / Q000502:physiology*
D009292:Narcotic Antagonists; D017465:Receptors, Opioid, delta; D014316:Tritium; D004174:Diprenorphine