Temporal expression patterns of osteoblastic and osteocytic markers in the long-cultured osteoblastic MC3T3-E1 cells, and the effects of DMP1 treatment on these markers. (a) After 1, 2 and 3 weeks of culture of MC3T3-E1 cells in osteogenic medium, expression levels of Fgf23, Runx2, Osterix, Col1a1, bone-type alkaline phosphatases (Alp), Osteocalcin (Osc), Dmp1 and SOST s were analyzed by quantitative real-time PCR. (b) After 4 weeks of culture with or without DMP1, the gene expression levels were compared. GAPDH, glyceraldehyde 3-phosphate dehydrogenase.