Figure 4.

Dynamics of mRNA editing in response to environmental stresses. (A) A-to-I editing levels of selected target genes 15 min after dilution in pre-conditioned culture medium at 12°C, 30°C, 37°C and 42°C. Editing levels were normalised to t = 0 min for each replicate and gene. Statistical analysis was performed using replicate-matched one-way ANOVA with Dunnett's post-hoc test. (B) Changes in A-to-I editing levels of target genes in response to functionally related conditions. Left: effect of carbohydrate supplementation (0.5% w/v) on amyA editing after 30 min, statistical analysis using replicate-matched one-way ANOVA and Dunnett's post-hoc test. Middle: time-dependent effect of 0.5 mM ZnSO₄ on adcC editing, statistical analysis using paired t-tests with P-values adjusted for false discovery rate of 5% (procedure of Benjamini, Krieger and Yekutieli; q values shown for each comparison). Right: time-dependent effect of different doses of H₂O₂ (0.5 mM in light grey, 1.0 mM in dark grey) on SPy_1219 editing, statistical analysis using two-way ANOVA with Dunnett's post-hoc test. Editing levels were normalised to the mock-treated control for each replicate. p.i. = post induction. (C) A-to-I editing levels of selected target genes 30 min after exposure to the conditions described in (B) (Glc: 0.5% glucose; zinc: 0.5 mM ZnSO₄; H₂O₂: 1 mM H₂O₂). Editing levels were normalised to the mock-treated control for each replicate and gene. Statistical analysis was performed using paired t-tests, and P-values were adjusted for a false discovery rate of 5% using the procedure of Benjamini, Krieger and Yekutieli. (D)S. pyogenes SF370 was treated with 0.5 mM and 1.0 mM H₂O₂ at mid-logarithmic growth phase for 15 min and 30 min, and A-to-I editing levels were examined by RNA sequencing. The absolute editing levels of each replicate were transformed into editing z scores and are represented as a heatmap. For replicates depicted as grey tiles with a black cross, editing could not be determined due to filtering steps. *** P < 0.001; ** P < 0.01; * P < 0.05; ns, not significant.