title: A timekeeping enzyme in the pineal gland.
mesh_terms: D000121:Acetylserotonin O-Methyltransferase / Q000378:metabolism; D000123:Acetyltransferases / Q000378:metabolism*; D000818:Animals; D001683:Biological Clocks; D002645:Chickens; D002940:Circadian Rhythm; D008027:Light; D008550:Melatonin / Q000502:physiology; D010870:Pineal Gland / Q000502:physiology*; D012701:Serotonin / Q000502:physiology
chemical_list: D012701:Serotonin; D000121:Acetylserotonin O-Methyltransferase; D000123:Acetyltransferases; D008550:Melatonin