High-throughput screening assay for new ligands at human melatonin receptors.
OBJECTIVE
Melatonin (MT) is a neurohormone produced and secreted primarily by the pineal gland in a circadian manner, and mainly acts through 2 receptor subtypes: MT1 and MT2 in humans. The diversity in their tissue distribution is in favor of different functions for each receptor subtype. Selective modulators are therefore required to determine the physiological roles of these melatonin receptor subtypes and their implications in pathological processes.


METHODS
A homogenous MT1/MT2 receptor binding assay was established for high-throughput screening of new ligands at the hMT1 and/or hMT2 receptors. The functional properties (agonists or antagonists) were assessed by a conventional guanosine-5'[gamma-(35)S] triphosphate (GTP-gammaS) assay.


RESULTS
Three hMT1 receptor-selective small molecule antagonists and 1 hMT2 receptor-selective small molecule antagonist with novel structural features were identified following a high-throughput screening campaign of 48,240 synthetic and natural compounds.


CONCLUSIONS
The findings may assist in the expansion of chemical probes to these 2 receptor subtypes.
Yan
Jian-hua
JH
The National Center for Drug Screening and State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China.
Su
Hao-ran
HR
Boutin
Jean A
JA
Renard
M Pierre
MP
Wang
Ming-wei
MW
D000818:Animals; D006801:Humans; D008024:Ligands; D008550:Melatonin / Q000737:chemistry / Q000378:metabolism; D015394:Molecular Structure; D011869:Radioligand Assay / Q000379:methods*; D044122:Receptor, Melatonin, MT1 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D044123:Receptor, Melatonin, MT2 / Q000037:antagonists & inhibitors / Q000378:metabolism*
D008024:Ligands; D044122:Receptor, Melatonin, MT1; D044123:Receptor, Melatonin, MT2; D008550:Melatonin