Targeting of csgD by the small regulatory RNA RprA links stationary phase, biofilm formation and cell envelope stress in Escherichia coli
| Autor: | Janine Berkholz, Nicole Sommerfeldt, Natalia Tschowri, Regine Hengge, Franziska Mika, Alexandra Possling, Susan Busse, Mihaela Pruteanu |
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| Rok vydání: | 2012 |
| Předmět: |
Sigma Factor
Biology Regulon Microbiology 03 medical and health sciences Bacterial Proteins Cell Wall Sigma factor Transcription (biology) Gene expression Escherichia coli Protein biosynthesis RNA Messenger Molecular Biology Research Articles 030304 developmental biology Regulation of gene expression 0303 health sciences Binding Sites 030306 microbiology Escherichia coli Proteins Gene Expression Regulation Bacterial Cell biology RNA Bacterial Biochemistry Biofilms Protein Biosynthesis Trans-Activators biology.protein Diguanylate cyclase Phosphorus-Oxygen Lyases rpoS |
| Zdroj: | Molecular Microbiology |
| ISSN: | 1365-2958 0950-382X |
| DOI: | 10.1111/j.1365-2958.2012.08002.x |
| Popis: | RprA is a small regulatory RNA known to weakly affect the translation of σ(S) (RpoS) in Escherichia coli. Here we demonstrate that csgD, which encodes a stationary phase-induced biofilm regulator, as well as ydaM, which encodes a diguanylate cyclase involved in activating csgD transcription, are novel negatively controlled RprA targets. As shown by extensive mutational analysis, direct binding of RprA to the 5'-untranslated and translational initiation regions of csgD mRNA inhibits translation and reduces csgD mRNA levels. In the case of ydaM mRNA, RprA base-pairs directly downstream of the translational start codon. In a feedforward loop, RprA can thus downregulate 30 YdaM/CsgD-activated genes including those for adhesive curli fimbriae. However, during early stationary phase, when csgD transcription is strongly activated, the synthesis of csgD mRNA exceeds that of RprA, which allows the accumulation of CsgD protein. This situation is reversed when csgD transcription is shut off - for instance, later in stationary phase or during biofilm formation - or by conditions that further activate RprA expression via the Rcs two-component system. Thus, antagonistic regulation of csgD and RprA at the mRNA level integrates cell envelope stress signals with global gene expression during stationary phase and biofilm formation. |
| Databáze: | OpenAIRE |
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