Figure 3.
Ser-32 and Ser-36 are required for IκBα degradation in response to IR, but not by UV-C. Pools of stably transfected HeLa cells expressing HA-tagged wild-type IκBα or the IκBα AA mutant were either untreated or exposed to UV-C (40 J/m2) (A), IR (20 Gy) (B), and TNF (10 ng/ml). At the indicated times, lysates were prepared, separated by SDS/PAGE, and immunoblotted with anti-IκBα. Lanes Un and C, untransfected and untreated transfected cells, respectively. The migration positions of endogenous IκBα and the transfected HA-IκBα are indicated. To visualize HA-tagged IκBα the film was overexposed.