Specific stabilization of osmo-mRNAs during mild osmotic stress. (A) Global distribution of genes according to their destabilization (<0) or stabilization (>0) indexes (see Materials and Methods). Arrows in the histogram indicate the position of the genes whose mRNA half-lives have been checked by conventional methods. (B) Determination of mRNAs half-lives (t 1/2) before and after mild osmotic stress. Strains PAY500 (rpb1-1ts ), PAY498 (rpb1-1ts tetO2 -RTN2), and PAY495 (rpb1-1ts tetO2 -STL1) were grown in YPD until exponential phase and, before or after treatment for 5 min with NaCl 0.4 M, transcription was stopped by shifting the cells to 37°C and adding doxycycline (10 μg/mL). Aliquots were taken at the indicated times and RA of the indicated genes were determined by Northern analysis (using rRNA18S signal as a loading control). The half-life value of a representative experiment is shown. (C) mRNA half-life change after mild osmotic stress. Mean half-life change (%) for the indicated mRNAs was calculated from at least three independent experiments. Error bars represent the standard deviation.
