Effects of carminic acid on gene expressions under epigenetic regulation

Carminic acid, which is an anthracene derivative, is a dye used as a food additive. Although anthracene is considered not to be epigenetic modifier, some anthracene derivatives affect yeast flocculation that is under the epigenetic regulation. FLO assay can detect the expression of Saccharomyces cerevisiae FLO1 gene that mediates the flocculation phenotype influenced by epigenetic regulation. FLO reporter assays showed that 5-20 μM carminic acid induced the FLO1 promoter in wild type yeast as well as in the yeast transformed with human DNA methyltransferase genes, in the absence of rat liver homogenates. Furthermore, in mouse embryonic stem cell line EB3, carminic acid decreased the expression of Oct3/4, which is also under epigenetic regulation, and induced slight morphological changes. These results suggest that carminic acid, but not its metabolites, has the potential to alter the epigenetic state of the genome.