Vitamin D receptors (VDRs) are proteins found in the majority of cells in the human body that are responsible for mediating the biological effects of vitamin D. These receptors are specifically designed to allow the binding and activation of vitamin D, a fat-soluble nutrient that is crucial for various physiological functions.
VDRs belong to a family of nuclear receptors, which means they are located within the cell nucleus and can directly influence gene expression. When vitamin D binds to the VDR, it undergoes a conformational change that enables it to interact with specific regions of DNA known as vitamin D response elements (VDREs). This interaction triggers a series of molecular events that ultimately lead to the regulation of target genes involved in processes such as calcium homeostasis, bone health, immune system modulation, and cell growth.
The presence of VDRs in different tissues and organs of the body highlights the widespread impact of vitamin D on overall health. These receptors have been identified in the intestines, kidneys, bone cells, immune cells, and many other cell types. By activating VDRs, vitamin D plays a crucial role in maintaining optimal bone density, facilitating the absorption of dietary calcium and phosphorus, modulating immune responses, reducing inflammation, and regulating cell differentiation.
In summary, vitamin D receptors are proteins present in various cells throughout the body that enable the biological effects of vitamin D. Their activation by vitamin D plays a critical role in regulating gene expression and carrying out essential functions related to bone health, immune system function, and overall cellular activities.
