Figure 5: Myc differentially regulates the transcription of GFAP and Nestin genes in GBM cells.

U251 (A, B & D) and U87 (C, E & F) cells (1×10⁶) were transfected with 2 µg GFAP-Luc (A, D & E) or 2 µg Nestin-Luc (B, C, & F) reporter construct along with indicated amounts of Myc expression plasmid (or empty vector) (A, B & C) or two different Myc-specific shRNAs (Sh #2 and #3) (D, E, & F). GFAP promoter (A, D & E) and Nestin enhancer (B, C & F) activities were determined at 72 h post transfection by luciferase assay and normalized percent luciferase activities are plotted as mean ± SE (n=3). * and ** indicate p < 0.05 and p < 0.01 respectively. 2×10⁶ parental U251 or p300-shRNA-expressing stable clone (Sh#1-clone 10) were treated with 20% FBS for 4 h and subjected to ChIP using anti-Myc or matched IgG antibodies (G & H). Myc recruitment to the GFAP promoter (G) or the Nestin enhancer (H) was determined by PCR using radio-labeled primers and product densities plotted as ‘percent of input’.