Fig. 5.

The recruitment of Cdk9 to the chromatin and Ser2 phosphorylation of RNAP II CTD responsible for IL-1β- or TNF-α-induced transcription. a–d Human chondrocytes were pretreated with or without I-BET151 (1 μM), followed by addition of vehicle, IL-1β (10 ng/ml) or TNF-α (10 ng/ml) for 6 h, and ChIP assays were performed for Cdk9. e–h Human chondrocytes were pretreated with or without I-BET151 (1 μM), followed by addition of vehicle, IL-1β (10 ng/ml) or TNF-α (10 ng/ml) for 6 h, and ChIP assays were performed for S2P Pol II. The quantitative analysis of targeted promoter regions was determined by real-time PCR using specific primers for MMP1, MMP3, MMP13, and ADAMTS4. Relative fold-change values were calculated in comparison with the vehicle control that was set to 1 (n = 2)