Fig. 5.

PTAF regulates the expression and activity of miR-25. a PTAF contains a sequence domain complementary to the seed motif of miR-25. b Up-regulation of PTAF in OvCa cells treated with 10 ng/ml TGF-β1 for 48 h. n = 6 independent experiments. **P < 0.01 vs. Control. c-d Overexpression of PTAF inhibited the expression of miR-25 in SKOV3 cells. n = 6 independent experiments. **P < 0.01 vs. pcDNA3.1. e-f Silencing of PTAF using a specific shRNA up-regulated miR-25 in SKOV3 cells. n = 6 independent experiments. *P < 0.05, **P < 0.01 vs. sh-Scramble. g-h PTAF binds to miR-25 and regulates its activity. *P < 0.05, **P < 0.01. i PTAF directly binding to miR-25. SKOV3 cells were transfected with biotin-tagged miR-Ctrl (Bio-miR-Ctrl) or biotin-tagged miR-25 (Bio-miR-25). Forty-eight hours after transfection, the cells were harvested for a biotin-based pull-down assay. PTAF expression levels were analyzed by qRT-PCR. **P < 0.01. j Luciferase reporter activities of chimeric vectors carrying the luciferase gene and a fragment of PTAF containing the wild-type (WT) binding site or a mutated binding site for miR-25. **P < 0.01. k-l qRT-PCR were used to examine the expression of PTAF in SKOV3 cells after overexpression or knockdown of miR-25. *P < 0.05, **P < 0.01. n = 6 independent experiments