N-Acetylserotonin O-methyltransferase (ASMT)

N-Acetylserotonin O-methyltransferase (ASMT) is an enzyme that catalyzes the final step in the biosynthesis of melatonin, converting N-acetylserotonin to melatonin. ASMT is coded by the ASMT gene, which is located in the pseudoautosomal regions of the X and Y chromosomes in humans. The enzyme belongs to the transferase and methyltransferase family, specifically transferring a methyl group from S-adenosyl-L-methionine to N-acetylserotonin. ASMT activity is most prominent in the pineal gland and retina, and it thus plays a central role in regulating circadian rhythms and sleep through melatonin synthesis. Genetic variants affecting ASMT have been associated with neurodevelopmental and neuropsychiatric conditions, including depression and autism spectrum disorder. Modulation of ASMT activity could hold therapeutic potential for circadian and mood disorders, but clinical application is early and no direct ASMT-targeting drugs are currently approved[1][3][4].

Other names

hydroxyindole O-methyltransferaseHIOMTacetylserotonin methyltransferaseASMTYacetylserotonin N-methyltransferaseASMT (Y chromosome)acetylserotonin O-methyltransferase

Inhibition of ASMT would block the methylation of N-acetylserotonin, thereby reducing melatonin synthesis. Modulation of ASMT activity could impact the sleep-wake cycle, circadian rhythm regulation, and possibly mood regulation due to altered melatonin and serotonin levels[1][3][4]