Fig. 3.

Effect of rstA on EHEC O157 adherence and LEE genes expression. a A heat map representing differential regulation of virulence genes in the EHEC O157 WT and mutant strains. The z-score indicates whether the genes were upregulated (red) or downregulated (green). b qRT-PCR analysis of changes in LEE genes expression in EHEC O157 WT, ΔrstA mutant, and rstA complementary strain. c Adherence of EHEC O157 WT, the ΔrstA mutant, rstA complementary strain to HeLa cells. d Growth of EHEC O157 WT, the ΔrstA mutant, rstA complementary strain in LB medium. e Adherence capacity of EHEC O157 WT, ΔrstA mutant and rstA complementary strain in the distal colon of mice at 6 h. Statistical significance was assessed using the Mann–Whitney rank-sum test. f Detection of AE lesion formation by EHEC O157 WT, ΔrstA mutant, and rstA complementary strain by FAS in HeLa cells at 3 h. The HeLa cell actin cytoskeleton (green) and nuclei of bacterial and HeLa cells (red) are shown. AE lesions are indicated by arrowheads. g The number of pedestals/infected HeLa cell of EHEC O157 WT, ΔrstA mutant, and rstA complementary strain (n = 50 cells). In b–d, data represent mean ± SD (n = 3). *P ≤ 0.05, **P ≤ 0.01, ***P ≤ 0.001 (Student’s t-test)