The vitamin D receptor (VDR) is a nuclear receptor that is activated by vitamin D and regulates gene expression for a variety of biological processes, including calcium homeostasis, bone metabolism, immune response, cell proliferation, differentiation, and apoptosis. The VDR luciferase reporter vector is designed to study the transcriptional activity of this receptor. The vector contains a VDR DNA consensus binding site and TA minimal promoter upstream of a firefly luciferase reporter gene, which can specifically report VDR activity while maintaining a low basal level of transcription. immune function, and cell differentiation.