RAC1 and Salmonella Infections: ELMO1 binds and stabilizes Dock180, which in turn activates Rac1.24 Interestingly, we found that ELMO1 activates Rac1 during Salmonella infection.9 To assess the impact of ELMO1–SifA interaction on Rac1 activation, control and ELMO1 shRNA J774 cells were infected with WT SL or the sifA mutant strain for 1 h (Figure 4(a)).