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Objective: Peroxisome proliferator-activated receptor γ (PPARγ), considered to be the master regulator, is both necessary and sufficient for adipogenesis. However, there are few reports regarding the effect of PPARγ regulation on osteogenic and adipogenic differentiation in rat bone marrow stromal cells (BMSCs) and no reports about tissue targeting and conditional control of PPARγ gene silencing. The purpose of this study is to investigate the effect of PPARγ gene silencing on osteogenic and adipogenic differentiation in rat BMSCs. Materials and Method: In this study, we construct rats PPARγ gene shRNA Tet-on lentiviral vector, the lentiviral vector facilitated tetracycline (which has the characteristics of bone targeting)-inducible knockdown specific to PPARγ gene, and transfect it into BMSCs. Cultured BMSCs were transfected with the PPARγ-shRNA or a non-target control shRNA (shNTC), cells were cultured in osteogenic or adipogenic medium for 14 days, we determine the osteogenic and adipogenic gene and protein levels by RT-PCR and Western blot assays, the differentiation of BMSCs were analyzed by alkaline phosphatase (ALP), Oil red O staining, Alizarin red S staining, calcium deposition. Results: The silencing effects induced by tetracycline is significant. The expression of the adipogenic factors adipocyte determination and differentiation-dependent factor 1 (ADD1) and recombinant CCAAT/enhancer binding protein alpha (C/EBPα) were decreased as measured by RT-PCR and Western blot assay following PPARγ silencing. In contrast, expression of the osteogenic genes encoding collagen I and Cbfa1/Runx2 were increased. In adipogenic medium, PPARγ-shRNA transfection reduced the lipid droplet count as measured by Oil red O staining when compared to the control groups. In osteogenic medium, PPARγ-shRNA increased the activity of alkaline phosphatase and the amount of calcium deposition as measured by Alizarin red S staining. Conclusion:These results suggest that the rats PPARγ gene shRNA Tet-on lentiviral vector decreases adipogenic differentiation and promotes osteogenic differentiation in BMSCs induced by tetracycline.