Regulation of arsenic methylation: identification of the transcriptional region of the human AS3MT gene

The human enzyme As(III) S-adenosylmethionine methyltransferase (AS3MT) catalyzes arsenic biotransformations and is considered to contribute to arsenic-related diseases. AS3MT is expressed in various tissues and cell types including liver, brain, adrenal gland, and peripheral blood mononuclear cells but not in human keratinocytes, urothelial, or brain microvascular endothelial cells. This indicates that AS3MT expression is regulated in a tissue/cell type-specific manner, but the mechanism of transcriptional regulation of expression of the AS3MT gene is not known. In this study, we define the DNA sequence of the core promoter region of the human AS3MT gene. We identify a GC box in the promoter to which the stress-related transcription factor Sp1 binds, indicating involvement of regulatory elements in AS3MT gene expression.

Automated summary

AS3MT is a human enzyme that catalyzes arsenic biotransformations and is considered to contribute to arsenic-related diseases. The expression of AS3MT is tissue/cell type-specific, and the transcriptional regulation mechanism of the gene is still unknown. In this study, the core promoter region of the human AS3MT gene is defined, and a GC box in the promoter is identified as a site where the transcription factor Sp1 binds, indicating the involvement of regulatory elements in AS3MT gene expression.