Fig. 6.

Two RTA-responsive elements and the RBP-Jκ-binding site are required for RTA-mediated transactivation. (a) Schematic representation of the ORF57 promoter reporter constructs and various deletion and site-directed mutagenesis clones used in the transient transfection analysis. Solid lines indicate different regions of the ORF57 promoter segment with various deletions (thin lines) or mutated regions (hatched boxes). The responsiveness of each reporter to RTA transactivation is indicated. (b, c) BJAB cells were used to analyse the promoter activity of different ORF57 reporter constructs. The total DNA amount used in each transfection was normalized by adding pCMVTag2A vector. Transfection of BJAB cells was carried out with 0.8 μg promoter reporter and 1 μg RTA expression plasmid. Luciferase activity was measured at 48 h post-transfection.