Figure 2

Impact of Hfq on rpsO mRNA degradation pathways. Comparison of the rpsO mRNA abundance and stability in pcnB (A) and rne 3071 (B) mutants bearing hfq⁺ or hfq 1 alleles. (A) Cells were grown at 37°C. (B) Cells were grown at 30°C and shifted to 44°C to inactivate thermosensitive RNase E just before the addition of rifampicin. Northern-blot analysis was performed as described in the legend to Fig.1. Time intervals (min) after treating the cultures with rifampicin are indicated above the lanes. Below each Northern blots, relative amounts of the rpsO mRNA (normalized to 5S RNA) for 0 time (before treating with rifampicin) are indicated. Time points 0 to 4 min and 0 to 16 min. were used to calculate the half-lives in the pcnB mutants (Fig. 2A) and rne strains (Fig. 2B) respectively.