MT3 indirectly regulates Runx2/Osterix/Dlx5 activation during osteoblast differentiation. (A) Luciferase reporter activities of Runx2, Osterix, and Dlx5 in control or MT3-overexpressing 293T cells. (B) Luciferase reporter activities of Runx2, Osterix, and Dlx5 in control or MT3-overexpressing C2C12 cells treated with or without recombinant BMP4 for 72 h. (C) Luciferase reporter activities of Runx2, Osterix, and Dlx5 in control or MT3 knockdown 293T cells. (D) Luciferase reporter activities of Runx2, Osterix, and Dlx5 in control or MT3 knockdown C2C12 cells treated with or without recombinant BMP4 for 72 h. All data are presented as mean ± SEM, # p < 0.05.