Figure 4.

Over-expression of FimR and SQ18 antisense sRNAs regulates the fimD and gbs0031 target genes, respectively. (A) Analysis by Western blot and quantitative RT–PCR of gfp and FimR gene expression in E. coli strain TOP10 harboring pZE2R-fimR or pZE2R-null plasmids combined with pXG-0 (no gfp target control) or pXGfimD::gfp target expression plasmids. The four isolates were cultured in LB medium at 37°C until they reached an OD₆₀₀ of 0.9. Quantitative expression of the gfp fusion gene was normalized to 1.0 for the TOP10 + pZE2R-null + pXGfimD::gfp strain. FimR expression was normalized to 1.0 for the TOP10 + pZE2R-fimR + pXG-0 strain. (B) Western blot and quantitative RT–PCR analysis were performed as described in (A) but in a Δhfq context. Asterisks indicate a significant difference between mean values in unpaired t-tests (P < 0.01).