Figure 8.

WT1 17AA is a UV light responsive transcriptional activation domain in vivo. (A) Plasmids expressing GAL4, GAL4 D−, GAL4 D+, and GAL4 D+ G253A (4 μg each) were transfected into embryonic kidney 293 cells along with the reporter G₅E4CAT (1 μg). Six hours after UV light treatment of the cells, CAT activity was measured and is presented relative to the level of CAT activity with empty pCDNA3 vector alone (0 lane). The results are the mean average of four independent experiments. (B) Immunoblot with anti-par4 antibodies showing that the level of par4 is elevated in 293 cells that have been treated with UV light. (C) Coimmunoprecipitation of par4 with the WT1 17AA motif. 293 cells were transfected with 4μg of each GAL4 derivative and after UV light treatment nuclear extracts were prepared. Immunoprecipitation was performed with either anti-GAL4 or anti-TFIIH antibodies and complexes harvested with protein G Sepharose. Par4 content was assessed by immunoblotting. Input (I) is 1% of the amount of nuclear extract used in each immunoprecipitation.