Abl and Arg localize in EPEC pedestals. (a–d) Images of 3T3 cells (a–d) exposed to EPEC and stained with DAPI to identify EPEC, FITC-phalloidin to visualize actin, and α-Abl mAb 8E9 (a and b) or α-Arg pAb (c and d). In these merged images and in h and l, EPEC are pseudocolored blue, Abl or Arg red, and actin green. Note that α-Abl mAb and α-Arg pAb recognize proteins beneath EPEC in 3T3 cells. (e–h) Images of 3T3 cells expressing exogenous HA-Abl and exposed to EPEC and stained with DAPI (e), FITC-phalloidin (f), and α-HA (g). (i–l) Images of 3T3 cells expressing exogenous YFP-Arg (k) and exposed to EPEC and stained with DAPI (i) and Alexa 594-phalloidin (j). Together, these results suggest that both exogenous and endogenous Abl and Arg localize in pedestals. Supplementary Figure 1 shows that α-Abl mAb and α-Arg pAb are specific and recognize only Abl or Arg, respectively. Bars, 5 μm.