Fig. 5. Trp53 regulates the stability and activity of TAZ in chondrocytes.
A The luciferase activity was measured by Promega® Luciferase Assays kit in primary chondrocytes as indicated. B Luciferase activity was measured in the primary chondrocytes the following co-transfection with pEGFP (control), pEGFP-Trp53, respectively. C Whole protein lysates of primary chondrocytes as indicated were detected by western blot. D TAZ expression in cytoplasm and nucleus as indicated. E Representative fluorescence images of TAZ in primary chondrocytes as indicated. Scale bars, 25 μm. F, G mRNA level of CYR61 and CTGF in primary chondrocytes as indicated. H Primary chondrocytes from Trp53f/f mice were transfected with Ad-Cre or Ad-GFP, after 24 h, the cells were treated for different time as indicated with 50 μg/mL cycloheximide (CHX). The TAZ expression was identified by western blot. I Co-IP experiments were performed after transfection of plasmid GFP-Trp53 or/and flag-TAZ in HEK293T cells as indicated. J Co-IP experiments in primary chondrocytes as indicated. K Western blot analysis of TAZ ubiquitination demonstrating that Trp53 is necessary for TAZ ubiquitination. **P < 0.01.