RNase III Controls the Degradation of corA mRNA in Escherichia coli

AbstractRapid modulation of RNA function by endoribonucleases during physiological responses to environmental changes is known to be an effective bacterial biochemical adaptation. We report a molecular mechanism underlying the regulation of enolase (eno) expression by two endoribonucleases, RNase G and RNase III, the expression levels of which are modulated by oxygen availability in Escherichia coli. Analyses of transcriptional eno-cat fusion constructs strongly suggested the existence of cis-acting elements in the eno 5′ untranslated region that respond to RNase III and RNase G cellular concentrations. Primer extension and S1 nuclease mapping analyses of eno mRNA in vivo identified three eno mRNA transcripts that are generated in a manner dependent on RNase III expression, one of which was found to accumulate in rng-deleted cells. Moreover, our data suggested that RNase III-mediated cleavage of primary eno mRNA transcripts enhanced Eno protein production, a process that involved putative cis-antisense RNA. We found that decreased RNase G protein abundance coincided with enhanced RNase III expression in E. coli grown anaerobically, leading to enhanced eno expression. Thereby, this posttranscriptional up-regulation of eno expression helps E. coli cells adjust their physiological reactions to oxygen-deficient metabolic modes. Our results revealed a molecular network of coordinated endoribonuclease activity that post-transcriptionally modulates the expression of Eno, a key enzyme in glycolysis.

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Escherichia coli YmdB regulates biofilm formation independently of its role as an RNase III modulator

BMC Microbiology ◽

10.1186/1471-2180-13-266 ◽

2013 ◽

Vol 13 (1) ◽

pp. 266 ◽

Cited By ~ 9

Author(s):

Taeyeon Kim ◽

Juyeon Lee ◽

Kwang-sun Kim

Keyword(s):

Escherichia Coli ◽

Biofilm Formation ◽

Rnase Iii

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Different Processing of an mRNA Species inBacillus subtilis and Escherichia coli

Journal of Bacteriology ◽

10.1128/jb.182.3.689-695.2000 ◽

2000 ◽

Vol 182 (3) ◽

pp. 689-695 ◽

Cited By ~ 8

Author(s):

Martin Persson ◽

Elisabeth Glatz ◽

Blanka Rutberg

Keyword(s):

Escherichia Coli ◽

Steady State ◽

Inverted Repeat ◽

Fusion Transcript ◽

Temperature Sensitive ◽

Rnase Iii ◽

Transcription Terminator ◽

E Coli ◽

Steady State Levels ◽

The Stability

ABSTRACT Expression of the Bacillus subtilis glpD gene, which encodes glycerol-3-phosphate (G3P) dehydrogenase, is controlled by termination or antitermination of transcription. The untranslated leader sequence of glpD contains an inverted repeat that gives rise to a transcription terminator. In the presence of G3P, the antiterminator protein GlpP binds toglpD leader mRNA and promotes readthrough of the terminator. Certain mutations in the inverted repeat of theglpD leader result in GlpP-independent, temperature-sensitive (TS) expression of glpD. The TS phenotype is due to temperature-dependent degradation of theglpD mRNA. In the presence of GlpP, theglpD mRNA is stabilized. glpDleader-lacZ fusions were integrated into the chromosomes ofB. subtilis and Escherichia coli. Determination of steady-state levels of fusion mRNA in B. subtilis showed that the stability of the fusion mRNA is determined by theglpD leader part. Comparison of steady-state levels and half-lives of glpD leader-lacZ fusion mRNA inB. subtilis and E. coli revealed significant differences. A glpD leader-lacZ fusion transcript that was unstable in B. subtilis was considerably more stable in E. coli. GlpP, which stabilizes the transcript in B. subtilis, did not affect its stability in E. coli. Primer extension analysis showed that theglpD leader-lacZ fusion transcript is processed differently in B. subtilis and in E. coli. The dominating cleavage site in E. coli was barely detectable in B. subtilis. This site was shown to be a target ofE. coli RNase III.

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Regulation of Expression of the adhE Gene, Encoding Ethanol Oxidoreductase in Escherichia coli: Transcription from a Downstream Promoter and Regulation by Fnr and RpoS

Journal of Bacteriology ◽

10.1128/jb.181.24.7571-7579.1999 ◽

1999 ◽

Vol 181 (24) ◽

pp. 7571-7579 ◽

Cited By ~ 28

Author(s):

Jorge Membrillo-Hernández ◽

E. C. C. Lin

Keyword(s):

Escherichia Coli ◽

Transcriptional Start Site ◽

Start Codon ◽

Start Site ◽

Rnase Iii ◽

Regulation Of Expression ◽

Experimental Conditions ◽

Stem Loop ◽

Translational Start ◽

Transcriptional Start Sites

ABSTRACT The adhE gene of Escherichia coli, located at min 27 on the chromosome, encodes the bifunctional NAD-linked oxidoreductase responsible for the conversion of acetyl-coenzyme A to ethanol during fermentative growth. The expression of adhEis dependent on both transcriptional and posttranscriptional controls and is about 10-fold higher during anaerobic than during aerobic growth. Two putative transcriptional start sites have been reported: one at position −292 and the other at −188 from the translational start codon ATG. In this study we show, by using several different transcriptional and translational fusions to the lacZ gene, that both putative transcriptional start sites can be functional and each site can be redox regulated. Although both start sites are NarL repressible in the presence of nitrate, Fnr activates only the −188 start site and Fis is required for the transcription of only the −292 start site. In addition, it was discovered that RpoS activatesadhE transcription at both start sites. Under all experimental conditions tested, however, only the upstream start site is active. Available evidence indicates that under those conditions, the upstream promoter region acts as a silencer of the downstream transcriptional start site. Translation of the mRNA starting at −292, but not the one starting at −188, requires RNase III. The results support the previously postulated ribosomal binding site (RBS) occlusion model, according to which RNase III cleavage is required to release the RBS from a stem-loop structure in the long transcript.

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