Fig. 4.
CtBP is required for the transcriptional regulation of SIRT1 by 2-DG. (A) Increased levels of SIRT1 transcript in CtBP-null MEFs. SIRT1 transcription in CtBP-null and heterozygous MEFs was measured by RT-PCR. Data were normalized to 18S RNA and are represented as mean ± SEM from three independent experiments. (B) CtBP knockdown in primary human fibroblasts up-regulates SIRT1 transcription. (Left) CtBP1 and -2 in human fibroblasts were knocked down by siRNA. (Right) Cells treated with siRNA (or control) were exposed to 2-DG before measurement of SIRT1 transcript levels. Data were normalized to 18S RNA and are represented as mean ± SEM from three independent experiments. con, control.