NFKB1 and infection: To determine the type of NF-κB pathway activated by Yersinia, we used RNA interference to deplete cellular levels of the non-canonical NF-κB kinase NIK prior to transfection with NF-κB luciferase reporter and infection with Yersinia. A representative NIK immunoblot shows a two-fold depletion of NIK levels upon RNA interference (S1 Fig), as typically seen in other studies [20–22].