Fig. 2.
Oligomeric CtBP increases transcription. (A) Expression of shRNA resistant Flag-CtBP mutants. HuTu 80 cells depleted of endogenous CtBP by an shRNA were examined for Flag protein expression by immunoblotting. (B) Effect of Fl-CtBP1-DMR on SCT-Luciferase reporter gene expression (column 4), in CtBP depleted HuTu 80 cells in the same experiment previously describing the effect of wild type Flag-CtBP1 (columns 1-3) [15]. The shRNA resistant mutants used in the reporter assays were expressed at comparable levels in the transfection experiments (right panel). Results are shown as the mean ± SEM (n>5). (C) Effect of CtBP on expression of endogenous SCT transcripts determined by real time PCR using RNA extracted under the indicated conditions. Relative mRNA expression was normalized to the housekeeping gene, ß-actin. Results expressed as the mean ± SEM (n=7). *P < 0.05, **P < 0.02, ***P < 0.0001. NS, not significantly different from CtBP KD cells.