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Selective translation during stress in Escherichia coli
Isabella Moll1, Hanna Engelberg-Kulka
1Department of Microbiology, Immunobiology and Genetics, Max F. Perutz Laboratories, University of Vienna, Dr. Bohrgasse 9, 1030 Vienna, Austria. Isabella.Moll@univie.ac.at
Trends in Biochemical Sciences
|September 4, 2012
Summary
Bacteria adapt to stress via a novel post-transcriptional mechanism. The MazF enzyme modifies ribosomes and messenger RNAs, enabling selective translation and demonstrating functional ribosome heterogeneity.
Area of Science:
- Microbiology
- Molecular Biology
- Bacterial Physiology
Background:
- Bacterial stress response traditionally viewed as transcriptional.
- Toxin-antitoxin (TA) modules play roles in bacterial survival.
- MazEF TA module involves MazF toxin and MazR antitoxin.
Purpose of the Study:
- Investigate novel post-transcriptional stress adaptation mechanisms.
- Elucidate the role of MazF in bacterial stress response.
- Characterize the functional impact of MazF-induced ribosome modification.
Main Methods:
- Analysis of Escherichia coli stress response.
- Identification and characterization of MazF activity.
- Ribosome and mRNA profiling under stress conditions.
Main Results:
- Discovery of a stress-induced modified ribosome in Escherichia coli.
- MazF endoribonuclease cleaves 16S rRNA and 5'-UTRs of specific mRNAs.
- Demonstration of selective translation mediated by MazF.
- Evidence for functional ribosome heterogeneity due to rRNA alteration.
Conclusions:
- MazF mediates a novel post-transcriptional stress adaptation strategy.
- This mechanism allows selective translation under stress.
- Represents the first instance of functional ribosome heterogeneity via rRNA modification.
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