Cold shock induction of RNase R and its role in the maturation of the quality control mediator SsrA/tmRNA
Article first published online: 7 NOV 2003
Volume 50, Issue 4, pages 1349–1360, November 2003
How to Cite
Cairrão, F., Cruz, A., Mori, H. and Arraiano, C. M. (2003), Cold shock induction of RNase R and its role in the maturation of the quality control mediator SsrA/tmRNA. Molecular Microbiology, 50: 1349–1360. doi: 10.1046/j.1365-2958.2003.03766.x
- Issue published online: 7 NOV 2003
- Article first published online: 7 NOV 2003
- Accepted 5 August, 2003.
In this paper we show that RNase R is a cold shock protein that is induced seven- to eightfold by cold shock and that its expression is tightly regulated by temperature. Transcriptional studies reveal that the rnr gene is co-transcribed with flanking genes as an operon induced under cold shock. The induction of RNase R levels is mainly a result of the stabilization of the rnr transcripts. The transient stability of the rnr transcripts is shown to be regulated by PNPase at the end of the acclimation phase. Studies with an rnr mutant revealed a cold-shock phenotype showing that RNase R contributes to growth at low temperatures. We have shown that RNase R can be involved in the maturation of SsrA/tmRNA, an important small stable RNA involved in protein tagging and ribosome rescue. The wide biological significance of RNase R regarding adaptation to cold shock and its involvement in RNA surveillance, protein quality control and pathogenesis is discussed.