Identification and characterization of two new human mu opioid receptor splice variants, hMOR-1O and hMOR-1X.
The mouse gene encoding the mu opioid receptor, Oprm, undergoes extensive alternatively splicing, with 14 variants having been identified. However, only one variant of human mu opioid receptor gene (Oprm), MOR-1A, has been described. We now report two novel splice variants of the human Oprm gene, hMOR-1O and hMOR-1X. The full-length cDNAs of hMOR-1O and hMO-1X contained the same exons 1, 2, and 3 as the original hMOR-1, but with exon O or exon X as the alternative fourth exon, respectively. Northern blots revealed several bands with the exon O probe in both human neuroblastoma BE(2)C cells and human brain and a single band (5.5kb) with the exon X probe in selected human brain regions. When transfected into CHO cells, both variants showed high selectivity for mu opioids in binding assays. These two new human mu opioid receptors are the first human MOR-1 variants containing new exons and suggest that the complex splicing present in mice may extend to humans.
Pan
Ying-Xian
YX
Department of Neurology, Laboratory of Molecular Neuropharmacology, Memorial Sloan-Kettering Cancer Center, 1275 York Ave, New York, NY 10021, USA. pany@mskcc.org
Xu
Jin
J
Mahurter
Loriann
L
Xu
Mingming
M
Gilbert
Annie-Kim
AK
Pasternak
Gavril W
GW
D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001921:Brain / Q000378:metabolism; D016466:CHO Cells; D006224:Cricetinae; D018076:DNA, Complementary / Q000235:genetics; D005091:Exons; D014644:Genetic Variation; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D017450:Receptors, Opioid, mu / Q000235:genetics* / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014162:Transfection; D014407:Tumor Cells, Cultured
D018076:DNA, Complementary; D017450:Receptors, Opioid, mu; D011994:Recombinant Proteins