In Vivo Function of VDR in Gene Expression: VDR Knock-Out Mice
TLDR Vitamin D receptor is crucial for bone health and mineral metabolism.
The study investigated the role of the vitamin D receptor (VDR) in gene expression by creating VDR knock-out (KO) mice. These VDR KO mice appeared normal until weaning but subsequently exhibited significant growth retardation and developed rickets, characterized by impaired bone formation and reduced bone density. The research demonstrated that VDR is crucial for the negative regulation of the 25(OH)D 1α-hydroxylase gene by vitamin D, which is essential for calcium homeostasis. The findings suggested that the 1α,25(OH)2D3–VDR system is vital for growth, bone formation, and hair development post-weaning, and the VDR KO mice phenotype resembled human vitamin D dependent rickets type II.