Figure 3. grcA reporters constructed to infer MazF-mediated mRNA processing.

(A) The grcA_wt reporter comprises 278 nt upstream of the start codon of grcA, as well as the first 15 codons fused in frame to EmgfpΔACA, which is a gfp variant devoid of ACA sites in the open reading frame (Sauert, 2015; Oron-Gottesman et al., 2016). The grcA_ATA reporter is a modified grcA_wt reporter harboring two nucleotide substitutions (C to T) at the positions previously determined to be processed by MazF (Vesper et al., 2011). (B) GFP and mCherry signals do not significantly differ between the grcA_wt and the grcA_ATA reporter measured in the exponential phase. Strains NN207 (depicted in blue) and NN214 (depicted in orange) harbor the grcA_wt and the grcA_ATA reporter, respectively, together with the constitutive λP_R-mCherry reporter. (C) The differences are neither significant for the variation in GFP and mCherry fluorescence. Variation is defined as the squared coefficient of variation, SCV. We analyzed N = 5 independent replicates.