uu.seUppsala University Publications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Turnover of mRNAs is an essential function of RNase E
Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology. Karolinska Institutet, Solna, Sweden. (Diarmaid Hughes)
Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology. (Diarmaid Hughes)
Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology. (Diarmaid Hughes)
Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology. (Diarmaid Hughes)
(English)Manuscript (preprint) (Other academic)
Keyword [en]
rpsA, vacB, RNaseR, RelBE, RNA turnover
National Category
Microbiology in the medical area
Research subject
Biology with specialization in Microbiology; Microbiology; Molecular Genetics
Identifiers
URN: urn:nbn:se:uu:diva-235199OAI: oai:DiVA.org:uu-235199DiVA: diva2:759331
Available from: 2014-10-29 Created: 2014-10-29 Last updated: 2015-02-03
In thesis
1. Genetics and Growth Regulation in Salmonella enterica
Open this publication in new window or tab >>Genetics and Growth Regulation in Salmonella enterica
2014 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Most free-living bacteria will encounter different environments and it is therefore critical to be able to rapidly adjust to new growth conditions in order to be competitively successful. Responding to changes requires efficient gene regulation in terms of transcription, RNA stability, translation and post-translational modifications.

Studies of an extremely slow-growing mutant of Salmonella enterica, with a Glu125Arg mutant version of EF-Tu, revealed it to be trapped in a stringent response. The perceived starvation was demonstrated to be the result of increased mRNA cleavage of aminoacyl-tRNA synthetase genes leading to lower prolyl-tRNA levels. The mutant EF-Tu caused an uncoupling of transcription and translation, leading to increased turnover of mRNA, which trapped the mutant in a futile stringent response.

To examine the essentiality of RNase E, we selected and mapped three classes of extragenic suppressors of a ts RNase E phenotype. The ts RNase E mutants were defective in the degradation of mRNA and in the processing of tRNA and rRNA. Only the degradation of mRNA was suppressed by the compensatory mutations. We therefore suggest that degradation of at least a subset of cellular mRNAs is an essential function of RNase E.

Bioinformatically, we discovered that the mRNA of tufB, one of the two genes encoding EF-Tu, could form a stable structure masking the ribosomal binding site. This, together with previous studies that suggested that the level of EF-Tu protein could affect the expression of tufB, led us to propose three models for how this could occur. The stability of the tufB RNA structure could be affected by the elongation rate of tufB-translating ribosomes, possibly influenced by the presence of rare codons early in the in tufB mRNA.

Using proteomic and genetic assays we concluded that two previously isolated RNAP mutants, each with a growth advantage when present as subpopulations on aging wild-type colonies, were dependent on the utilization of acetate for this phenotype. Increased growth of a subpopulation of wild-type cells on a colony unable to re-assimilate acetate demonstrated that in aging colonies, acetate is available in levels sufficient to sustain the growth of at least a small subpopulation of bacteria. 

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2014. 59 p.
Series
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Medicine, ISSN 1651-6206 ; 1052
Keyword
tufA, tufB, EF-Tu, ppGpp, Stringent response, RNase E, RNA turnover, Post-transcriptional regulation, rpoB, rpoS, Growth in stationary phase
National Category
Microbiology in the medical area
Research subject
Biology with specialization in Microbiology; Microbiology; Molecular Genetics; Biology with specialization in Molecular Evolution
Identifiers
urn:nbn:se:uu:diva-235224 (URN)978-91-554-9100-0 (ISBN)
Public defence
2014-12-16, B21, BMC, Husargatan 3, Uppsala, 09:00 (English)
Opponent
Supervisors
Available from: 2014-11-24 Created: 2014-10-29 Last updated: 2015-02-03

Open Access in DiVA

No full text

Authority records BETA

Bergman, Jessica M

Search in DiVA

By author/editor
Bergman, Jessica M
By organisation
Department of Medical Biochemistry and Microbiology
Microbiology in the medical area

Search outside of DiVA

GoogleGoogle Scholar

urn-nbn

Altmetric score

urn-nbn
Total: 450 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf