Figure 6.

Proinflammatory S. typhimurium induce Ca²⁺-dependent degradation of IκB-α. Immunoblots with anti–IκB-α antibodies. (a) Whole cell extracts were prepared at the indicated times from model intestinal epithelia treated with basolateral TNF-α, apical wild-type S. typhimurium (WT), HilΔ and PhoP^c mutants, and wild type with BAPTA-pretreated epithelia. (b) Monolayers were treated with basolateral ionomycin (1 μg/mL), thapsigargin (10 μM), or carbachol (100 μM) for the times indicated. (c) Model epithelia were treated with 20 μg/mL cycloheximide, S. typhimurium, or CHX 1 hour before S. typhimurium infection.