Determine in vivo the contribution of distal intestinal segments to calcium homeostasis and bone mineralization. Determine in vivo the contribution of distal intestinal segments to calcium homeostasis and bone mineralization

To explore this question, we will use three different male mouse models including VDR KO mice and transgenic mice with hVDR only expressed in the distal intestine (KO/VDR-Tg). All the mice which are C57BL6J background will be raised until 2-3 months old with standard chow diet (n=3 mice per genotype group). Compared to the KO/VDR-Tg mice without any injection, the same type of mice will be administered 1 ng/g bw 1,25(OH)2D3 at 48, 24 and 6 hours prior to termination to determine both early and late effects of 1,25(OH)2D3. Overall design: Mouse data comprising RNA-Seq from 21 samples was obtained: 11 from the colon (4 VDR knockout replicates, 3 VDR uninjected replicates, 4 VDR vitamin D treated replicates) and 10 from the ileum (4 VDR knockout replicates, 3 VDR uninjected replicates, 3 VDR vitamin D treated replicates).