Work

Expression cloning of a high-affinity melatonin receptor from Xenopus dermal melanophores.

Year: 1994

Type: article

Abstract: Using an expression cloning strategy, a high-affinity melatonin receptor cDNA has been isolated from Xenopus laevis dermal melanophores. Transient expression of the cDNA in COS-7 cells resulted in high-affinity 2-[125I]-iodomelatonin binding (Kd = 6.3 +/- 0.3 x 10(-11) M). In addition, six ligands exhibited a rank order of inhibition of specific 2-[125I]iodomelatonin binding that was identical to that reported for endogenous high-affinity receptors. Functional studies of CHO cells stably expressing the receptor cDNA showed that melatonin acting through the cloned receptor inhibited forskolin-stimulated cAMP accumulation in a dose-dependent manner. Northern blot analysis showed that melatonin receptor transcripts are moderately expressed in Xenopus dermal melanophores. The cDNA encodes a protein of 420 amino acids, which contains seven hydrophobic segments. Structural analysis revealed that the receptor protein is a newly discovered member of the guanine nucleotide binding protein-coupled receptor family.

Source: Proceedings of the National Academy of Sciences

DOI: 10.1073/pnas.91.13.6133

Authors: T Ebisawa, S Karne, M R Lerner, S M Reppert

Institutions: Massachusetts General Hospital, Howard Hughes Medical Institute, Yale University, Harvard University

Language: English

Topic: Circadian rhythm and melatonin

Subfield: Endocrine and Autonomic Systems

Field: Neuroscience

Domain: Life Sciences

Open Access status: green

Funders: Naito Foundation, National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases

Awards: MELATONIN--SITES AND MECHANISMS OF HORMONE ACTION, G3183438807