Fig. 3

Schematic illustration of epigenetic activity mediated by vitamin D₃ (VD). VD exerts its activity in association with its receptor (VDR) and other nuclear receptors such as the RXR and HAT, which transfers acetyl groups to histones and consequently loosens DNA structure resulting in activation of gene expression (probably including DNA demethylation). The chromatin of a previously inactive gene becomes relaxed upon binding of transcription factors to DNA recognition sequences. This process may be counteracted by recruitment of CBFA partner proteins such as TLE that interact with factors having HDAC activity