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(2006). https://pubmed.ncbi.nlm.nih.gov/16778767/ DOI: 10.1038/sj.emboj.7601193","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"GPR50-MT1/MT2 interactions","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null}],"evidence":[{"id":"0249b719-a0e1-5c0d-b4e9-1483c8e13d6a","evidence_kind":"source_excerpt","locator":"Lines 461-472","start_line":461,"end_line":472,"excerpt":"### melatonin-gpr50-mt1-coupling\nGPR50 abolished MT1 G-protein coupling within the heterodimer.\nCondition category: machinery_impairment\nnutrient_topic: Melatonin research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Available hormone and functional receptor machinery are different requirements.\norganism: Human receptors in cultured cells\ntissue_or_cell_type: GPR50-MT1/MT2 interactions\nexperimental_model: Biochemical and biophysical receptor heteromer experiments\nlimitations: Cell-system regulation; does not establish that a person with poor sleep has excess GPR50 or that more melatonin overcomes it.\nexposure: Full-length versus C-terminally truncated GPR50\nevidence_span: {\"source_cache\": \"artifacts/melatonin-research/16778767.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"19c9ae903fb7926bb21cc3bda0a610612b16a899f850b8e787581b72ac434135\", \"start_char\": 0, \"end_char\": 1204, \"text_sha256\": \"19c9ae903fb7926bb21cc3bda0a610612b16a899f850b8e787581b72ac434135\"}\n[melatonin-p16778767] The orphan GPR50 receptor specifically inhibits MT1 melatonin receptor function through heterodimerization. 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