Fig. 3: GrpP/GrpQ TCS promotes UPEC invasion by activating type 1 fimbria genes.
A qRT-PCR analyses of the mRNA levels of fimH in CFT073 cultured in mouse urine compared to that in CFT073 cultured in M9 medium for 2 h (n = 5 mice). B Volcano plot showing differentially expressed genes in the ΔgrpP/grpQ transcriptome versus WT cultured in LB medium. Data are expressed as a log2-fold change in gene expression levels (X-axis) plotted against the −log10 p-value (Y-axis). The red color indicates upregulated genes. The green color indicates downregulated genes. fim genes are marked by a black circle. Differentially expressed genes were tested by a two-part hurdle model; P-values were adjusted for multiple comparisons by the Bonferroni’s method. C qRT-PCR analyses of the mRNA levels of fim genes in ΔgrpP/grpQ and WT strains cultured in LB medium. D Western blot analysis of FimH protein levels in WT, ΔgrpP/grpQ, or ΔgrpP/grpQ+ statically grown in LB medium at 37 °C overnight. DnaK was used as the loading control. Representative image from three independent experiments. E HA assays of the production of type 1 fimbria in WT, ΔgrpP/grpQ, ΔgrpP/grpQ+, ΔfimA-H, ΔfimA-HΔgrpP/grpQ, WT-LIR, or ΔgrpP/grpQ-LIR in the presence or absence of 3% mannose. F, G Competitive index of ΔfimA-H versus ΔfimA-HΔgrpP/grpQ (F) or ΔgrpP/grpQ-LIR versus WT-LIR (G) in BALB/c mouse bladders at 2 h p.i. (n = 10 mice). Data were obtained from three independent experiments and presented as mean ± SD. P values were determined using two-tailed Student’s t-test (A, C and D) or two-way analysis of variance (E) or two-tailed Wilcoxon signal-rank test (F, G). Significance was indicated by a P value. n.s., No significant difference. C P = 0.0000000061 (fimH), P = 0.0000000083 (fimA), P = 0.0000000034 (fimC), P = 0.0000000015 (fimI), P = 0.0000000036 (fimD), P = 0.0000000173 (fimF), P = 0.0000000078 (fimG); D P = 0.000015; E P = 0.000052 (WT vs ΔfimA-H), P = 0.000052 (WT vs ΔfimA-HΔgrpP/grpQ). Source data are provided as a Source data file.
