fig2

Figure 2. RIP140 regulates POLK at the transcriptional level in CRC cells. (A) Schematic representation of POLK proximal promoter cloned in a pGL3 promoter and the putative regulatory sites identified as well as the POLK 29 Luc deletion mutant. (B) The POLK Luc construct was transiently co-transfected into HCT116 cells with increasing doses of a pEF-cmyc-RIP140 expression vector and pRL-CMV-renilla as an internal control. The reporter activity is presented as relative luciferase activity (RLU) as mean ± S.D. (n = 3 independent experiments). (C) The same reporter assay as in (B) performed in RKO, SW480, and SW620 cells. (D) Luciferase reporter assay performed with the two reporter vectors described in (A), in HCT116 cells. Values, expressed as a percent of control, are means ± S.D. (n = 3 independent experiments). (E) The effect of RIP140 ectopic expression on POLK mRNA levels after transient transfection in p53WT or p53KO HCT116 cells. (F) Transactivation of the POLK gene promoter by increasing doses of a RIP140 expression vector in p53WT or p53KO HCT116 cells. A Mann-Whitney test was used for statistical analysis (**P < 0.01 and ***P < 0.001).