Messenger RNA Turnover Processes in Escherichia coli, Bacillus subtilis, and Emerging Studies in Staphylococcus aureus. Int J Microbiol 2009:525491

Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198-6495, USA.
International Journal of Microbiology 03/2009; 2009:525491. DOI: 10.1155/2009/525491
Source: PubMed


The regulation of mRNA turnover is a recently appreciated phenomenon by which bacteria modulate gene expression. This review outlines the mechanisms by which three major classes of bacterial trans-acting factors, ribonucleases (RNases), RNA binding proteins, and small noncoding RNAs (sRNA), regulate the transcript stability and protein production of target genes. Because the mechanisms of RNA decay and maturation are best characterized in Escherichia coli, the majority of this review will focus on how these factors modulate mRNA stability in this organism. However, we also address the effects of RNases, RNA binding proteins, sRNAs on mRNA turnover, and gene expression in Bacillus subtilis, which has served as a model for studying RNA processing in gram-positive organisms. We conclude by discussing emerging studies on the role modulating mRNA stability has on gene expression in the important human pathogen Staphylococcus aureus.

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    • "The primary regulator of mRNA stability in E. coli in non-stress conditions is the endoribonuclease RNaseE, which sits at the center of a multiprotein mRNA degradasome complex (5). Bacillus subtilis and S. aureus do not have a direct homolog of RNaseE, but they do have RNases with similar function (3). In addition to the degradasome there are at least three other mechanisms by which prokaryotic RNA stability is regulated: accessory endoribonucleases (including toxin-antitoxin modules), exoribonucleases and interactions with RNA structure-modifying molecules (including pyrophosphatase and small non-coding RNAs) (3). "
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    • "Most RNases, including RNase J and RNase Y, which are thought to be the major RNases in B. subtilis, are shared with other Bacilli [15-17]. Indeed, the full complement of key RNases found in B. subtilis (RNase Y, RNase J1, RNase J2, RNase III, PNPase, RNase R, RNase PH, RNAse P, RNase Z, RNase HII, MazF/EndoA, YhaM, KapD, RNase HIII, RNase M5, YhcR) [18,19] are present in Bacillus cereus (GenBank and UniProt databases). RNase Bsn is also present in a range of B. cereus strains, but is, however, absent in the two B. cereus strains subject to study here. "
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    • "A variety of posttranscriptional regulatory strategies involve RNases. The cell can directly control global RNA decay by adjusting the levels of RNases [4] [5]. "
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