Figure 2: Characterization of cell-based LDR assay. (a) Visualization of GFP expression in cells treated with various known epigenetic modulators. TSA, butyrate, apicidin, and depsipeptide are HDAC inhibitors and 5-aza-deoxycytidine is a DNA methyltransferase inhibitor. (b) Cells exhibit dose-dependent GFP expression in response to HDAC inhibitors. (c) FACS analysis reveals an increase in number of cells expressing GFP when treated with butyrate or apicidin, compared to untreated cells.