A) Effect of treatment with 1,25D (10 nM, 6 hrs) on mRNA for the host genes (DAPK3 and LRP1) and target genes (COL4A1 and BMP2K) for miR-637 and miR-1228 respectively in passage 8 (P8) HOBS. B) Effect of treatment with 1,25D (10 nM, 6 hrs) on mRNA for vitamin D metabolism (CYP24A1) and osteoblast (osteocalcin, osteopontin) markers in passage 8 (P8) HOBS. Data and error bars represent mean ± SEM (n=3; * = p≤ 0.05; Student t test) of comparable arbitrary expression units. C) ChIP analysis of the miR-637 promoter after 1,25D treatment (15min, 10nM) showing VDR enrichment. CYP24A1 VDRE positive control and non-specific controls (calponin, TRPV6) lacking VDREs in specific regions are included. Data are mean ± SEM (n=3 HOB cultures; * = p≤ 0.05; Student t test) of comparable arbitrary enrichment units.