FIGURE 5.

Effect of 1α,25(OH)₂D₃ on gene transcription in wild-type and Sh-Pdia3 MC3T3-E1 cells. Wild-type and Sh-Pdia3 cells were treated with vehicle (ethanol) or 10⁻⁸ m 1α,25(OH)₂D₃. After 9 min, media were replaced with fresh media for another 8 h before harvest. Real-time PCR was performed against twelve bone-related genes: (a) osteopontin; (b) alkaline phosphatase; (c) matrix metalloproteinase 13; (d) osteoprotegerin; (e) osteocalcin; (f) Smad2; (g); inositol 1,4,5-trisphosphate 3-kinase A; (h) vitamin D receptor; (i) osteonectin; (j) Runx2; (k) Pdia3; and (l) bone sialoprotein. T/C represents the treatment over control ratio. Absolute values of targeting genes were first normalized by GAPDH. Then the normalized values from treatment groups were further divided by the normalized values from vehicle (ethanol) control groups. *, p < 0.05, treatment versus control; #, p < 0.05, Sh-Pdia3 versus WT for the same treatment.