PathwayStep2564 PathwayStep2562 PathwayStep2563 PathwayStep2561 Serotonin and melatonin biosynthesis Authored: Jassal, B, 2008-10-01 13:18:42 Edited: Jassal, B, 2008-05-28 09:06:10 GENE ONTOLOGYGO:0046219 Pubmed16942634 Pubmed18155917 Reactome Database ID Release 43209931 Reactome, http://www.reactome.org ReactomeREACT_15439 Reviewed: D'Eustachio, P, 2008-05-28 08:30:54 Serotonin (5-HT) is a hormone and neurotransmitter used for regulatory purposes in animal CNS. In the human brain, serotonin is involved in many physiological functions such as sleep, pain, mood and is the precursor to melatonin, a hormone produced in the pineal gland. Methylation of N-acetyl-5-HT to form melatonin N-acetylation of serotonin Decarboxylation of 5-hydroxytryptophan forms serotonin Tryptophan is hydroxylated