FIG. 4.

Effects of mutations in negative regulators on the expression of GFP reporters after infection of HEp-2 epithelial cells. FACS analysis was performed 2.5, 5, or 24 h after infection of epithelial cells with Salmonella hilE or hilE hha (a) and lon (b) mutant strains containing unstable (tagged) hilA, hilD, hilC, or ssrA-gfp reporters. The data presented are the mean plus the standard deviation of one experiment performed in duplicate that is representative of several independent experiments that had similar results. +, present; −, absent.