Fig. 3. RelA K221R, K310R and RelA-KR display impaired transcriptional activation properties. (A) 293T cells were transfected with E-selectin–luciferase reporter plasmid DNA (0.1 µg) and the various lysine-to-arginine substitution mutants of RelA (1 ng). Luciferase activity was measured as described previously (Chen,L. et al., 2001). Results represent the average of three independent experiments ± SD. (B) The HAT-deficient mutant of p300 inhibits RelA-mediated transactivation of RelA. 293T cells were transfected with E-selectin–luciferase reporter plasmid DNA (0.1 µg) and expression plasmid DNA encoding RelA (5 ng) alone or with graded amounts of p300 (HAT-) expression plasmid DNA (100 ng, 200 ng and 400 ng). Luciferase activity was measured as in (A). (C) Lack of cooperative transactivation of RelA-KR and p300/CBP. 293T cells were co-transfected with E-selectin–luciferase reporter plasmid DNA (0.1 µg) and either wild-type RelA or RelA-KR expression plasmid DNA (1 ng), alone or in combination with increasing amounts of p300 expression vector DNA (100 ng and 200 ng). Luciferase activity was measured as in (A).