Fig. 2. Infection with T. gondii induces IKK-dependent degradation of IB. (A,B) Whole cell extracts from HFF cells (A) or IKK/ß dKO 3T3 cells (B) treated with TNF- (left panels), or infected with T. gondii (right panels) were prepared at the times indicated. To assess IKK activity, in vitro kinase assays were performed as previously described (Zhong et al., 1997) (A, top panels) and gels were Coomassie Blue stained to confirm equal loading (A, middle panels). Immunoblots with anti-IB antibody (A, bottom panels) were performed to assess total levels in treated cells.