Fig. 2
From: The rationale for treating uveal melanoma with adjuvant melatonin: a review of the literature
Melatonin synthesis pathway. Tryptophan is hydroxylated by tryptophan hydroxylase (TPH) to 5-hydroxytryptophan which is subsequently decarboxylated by aromatic amino acid decarboxylase (AADC) resulting in serotonin. Serotonin is converted to N-acetylserotonin by Arylalkylamine N-acetyltransferase (AA-NAT) which is then catalyzed by N-acetylserotonin O-methyltransferase (ASMT) to produce melatonin