Fig. 3
Plot of the degradation rate constant as a function of the mRNA concentration for the rph-1 control strain, the rph-1 Δrnr and rph-1 Δpnp double mutants. For the 2856 genes with available half-lives in the three strains, the degradation rate constant k was plotted against the average mRNA concentration (normalized value) at T0 (before rifampicin addition). The rph-1 control is represented in black, the rph-1 Δrnr double mutant in red and the rph-1 Δpnp double mutant in green. Appling a K-means clustering algorithm, three correlation phases were distinguished: phase I, zone of highly significant (p-value < 10− 100) and very strong negative correlation (correlation coefficient ~ − 0.8) associated with low mRNA concentrations; phase II at intermediary mRNA concentrations with strong and significant negative correlation (correlation coefficient ~ − 0.65 and p-value < 10− 15); phase III, lack of correlation at high mRNA concentrations (correlation coefficient ~ 0)