Figure 1.

TSA, an inhibitor of histone deacetylation, stimulates rDNA transcription in transient transfection assays. NIH 3T3 cells were transfected with 1 µg rDNA reporter (pSMECAT) for 5 h and then treated with the indicated concentrations of TSA. After 19 h, cell lysates were prepared and assayed for CAT activity as described in Materials and Methods. Results were visualized and quantified using a Molecular Dynamics PhosphorImager. (A) Image of a CAT assay from a typical experiment. (B) Graph depicting the effect of TSA on the expression of pSMECAT (means ± SD, n = 12).