Vitamin D Receptor

The vitamin D receptor (VDR) is a ligand-dependent transcription regulator molecule belonging to the superfamily of nuclear receptors. VDR plays a central role in the biological actions of vitamin D involved in calcium/phosphate homeostasis, cellular proliferation and differentiation, and immune response. Activation of the VDR through direct interaction with 1,25(OH)2D3 induces heterodimerization with the retinoid X receptor (RXR) and translocation of 1,25(OH)2D3-VDR/RXR complexes into the nucleus. The complexes bind to specific DNA sequences called vitamin D response elements (VDRE) in target genes, and dependent on the recruited co-regulators either augment or inhibit transcription of the target gene.