FIG 3 .

Colistin acts as a general immune activator that elicits an expression profile similar to that elicited by Y. pestis infection. (A) Microarray results shows 2,538 up- and 1,864 downregulated genes in response to colistin treatment (2-fold; P < 0.05). F35E12.5 showed a >5-fold increase in the colistin-treated group compared to expression in the untreated group (P < 0.001). (B) Venn diagrams of genes that are upregulated by colistin and positively induced by Y. pestis and PMK-1. (C) Representation factors (RFs) of gene sets linked to immune or stress responses. RF is the number of overlapping genes divided by the expected number of overlapping genes drawn from the corresponding gene sets. A representation factor below 1.0 indicates underrepresentation, whereas a value above 1.0 indicates overrepresentation.