Fig 2.

Presence of Nramp1 in transfected RAW264.7 cells leads to the up-regulation of SPI2 and SPI2-associated virulence genes. Cells were infected with STM14028s carrying the plasmids containing the different transcriptional fusions. Patterns of expression over a 24-h time course are shown for the SPI1 regulatory gene hilA, the pleiotropic virulence regulatory gene phoP, the locus encoding the kinase for the two-component regulatory system that regulates SPI2, ssrA, the SPI2-encoded effector locus sseA, and the SP12 effector locus sseJ in RAW264.7 cell lines transfected with empty pCB6 vector (Nramp1−) or with pCB6 carrying a constitutively expressed wild-type Nramp1 gene (Nramp1+). These data are expressed as the average ratio of expression normalized to the initial observed level of expression at 2 h postinfection in the Nramp1− cell line and represent the mean ± the SEM of five separate experiments performed in duplicate. Statistical significance (P < 0.05) was determined by using the Wilcoxon rank sum test for unpaired samples.