The Molecular Biology of the Vitamin D Receptor

The document discussed the molecular biology of the vitamin D receptor (VDR), which mediated the biological effects of 1,25-dihydroxyvitamin D3 by binding with high affinity and selectivity. The interaction of this hormone with VDR in target cells initiated a cascade of molecular events that altered gene transcription rates. Key aspects included VDR's macromolecular interactions, such as its binding with the 1,25(OH)2D ligand, DNA interaction mechanisms, heterodimeric interaction with retinoid X receptor (RXR), and protein-protein contacts with transcriptional machinery. Notably, recent data suggested that VDR had transcriptional activity independent of the 1,25(OH)2D ligand in hair follicles and skin, indicating a novel role for VDR with significant implications for its transcriptional mechanism.