The small RNA RssR regulates myo-inositol degradation by Salmonella enterica.
Carsten KrögerJohannes E RothhardtDominik BrokatzkyAngela FelslStefani C KaryRalf HeermannThilo M FuchsPublished in: Scientific reports (2018)
Small noncoding RNAs (sRNAs) with putative regulatory functions in gene expression have been identified in the enteropathogen Salmonella enterica serovar Typhimurium (S. Typhimurium). Two sRNAs are encoded by the genomic island GEI4417/4436 responsible for myo-inositol (MI) degradation, suggesting a role in the regulation of this metabolic pathway. We show that a lack of the sRNA STnc2160, termed RssR, results in a severe growth defect in minimal medium (MM) with MI. In contrast, the second sRNA STnc1740 was induced in the presence of glucose, and its overexpression slightly attenuated growth in the presence of MI. Constitutive expression of RssR led to an increased stability of the reiD mRNA, which encodes an activator of iol genes involved in MI utilization, via interaction with its 5'-UTR. SsrB, a response regulator contributing to the virulence properties of salmonellae, activated rssR transcription by binding the sRNA promoter. In addition, the absence of the RNA chaperone Hfq resulted in strongly decreased levels of RssR, attenuated S. Typhimurium growth with MI, and reduced expression of several iol genes required for MI degradation. Considered together, the extrinsic RssR allows fine regulation of cellular ReiD levels and thus of MI degradation by acting on the reiD mRNA stability.
Keyphrases
- gene expression
- transcription factor
- binding protein
- poor prognosis
- dna methylation
- listeria monocytogenes
- staphylococcus aureus
- air pollution
- type diabetes
- magnetic resonance imaging
- computed tomography
- cell proliferation
- genome wide
- pseudomonas aeruginosa
- diabetic rats
- blood pressure
- long non coding rna
- insulin resistance
- high glucose
- heat shock protein
- endothelial cells
- cystic fibrosis
- adipose tissue
- stress induced
- heat shock