Figure 1.

SipA specifically binds and recruits host Syn8 on SCVs. (A) Immunofluorescence studies examining the recruitment of Syn8, Syn7, Syn13, Syn4, and Vti1a on SCVs using specific antibodies; cells were analyzed by confocal microscopy. Arrows indicate respective proteins on SCVs. Bottom: Relative levels of different Syntaxins on SCVs at indicated time points. Syn (green) and Salmonella (red) are shown. Results are mean ± SEM of three independent preparations. Levels of significance are indicated by P values in comparison with Syn8 (*). (B) To identify Syn8 binding protein from Salmonella, GST-Syn8 was immobilized on beads and incubated with SSPs as described in Materials and methods. (C) Identification of Salmonella-interacting protein by Western blot analysis using anti-SipA antibody. (D) To detect the binding of Syn8 with SipA, GST-Syn8 was immobilized, and beads were incubated with His₆-SipA. Binding of SipA with Syn8 was detected by Western blot analysis using anti-SipA antibody. Free GST immobilized on the beads was used as a control. All results are representative of three independent experiments.