FIG. 2.

Expression profile and TAF9 dependence of MLP and SV-MLP derivatives. Stable transfections of reporter constructs into DT40-TAF9 cells were carried out, and transfectants were analyzed individually after growing in media in the presence or absence of TET for 72 h (see Materials and Methods). (A) Promoter strength and activation potential of MLPs. Median expression levels under normal growing conditions, measured as luciferase units per 50 μg of extracts, were calculated for individual transfections and averaged over several independent experiments for each promoter. Averages are shown, with error bars indicating standard deviations. To the right, levels of induction (ratios of median expression between full and core promoters) are shown. (B) TAF9 dependence of promoter activity. Median reductions of reporter expression were calculated for individual transfections and averaged over independent experiments. C and SV, core and SVE-containing MLPs, respectively. Error bars represent standard deviations.