FIG. 4.

Trans activation phenotypes of Tax and Tax mutants. (A and B) HeLa cells were transiently transfected with RCV control (4 μg) (RCV), Tax (4 μg) (wild type [WT]), and Tax mutants (4 μg) (ΔN81, ΔN109, NLSΔN81, and NLSΔN109) and either the HTLV-1 LTR-CAT (2 μg) (A) or c-fos-CAT (4 μg) (B) reporter construct by the calcium phosphate method. (C, D, and E) An NF-κB reporter construct, 204K17 (0.25 μg), together with 0.25 (C), 0.5 (D), or 1 (E) μg of each Tax construct was transfected into CV1 cells by using Lipofectamine. Protein concentrations of the cell extracts were determined by Bradford assay. CAT assays were performed on extracts containing 100 μg of protein. The results shown are representative of three independent transfections.