Disease relevance of ssrA

• Dual regulation by phospho-OmpR of ssrA/B gene expression in Salmonella pathogenicity island 2 [1].
• The SopEPhi phage integrates into the ssrA gene of Salmonella enterica serovar Typhimurium A36 and is closely related to the Fels-2 prophage [2].
• Escherichia coli ssrA encodes a small stable RNA molecule, tmRNA, that has many diverse functions, including tagging abnormal proteins for degradation, supporting phage growth, and modulating the activity of DNA binding proteins [3].

High impact information on ssrA

• The isolated C-terminus of SsrB binds to DNA and protects regions upstream of ssrA, ssrB and srfH from DNase I digestion [4].
• Additional regulators clearly affect gene expression at this important locus, and here we provide evidence that SlyA, a transcription factor that contributes to Salmonella virulence, also affects ssrA/B gene expression [4].
• Results from DNase I protection assays provide direct evidence that SsrB binds at ssrA and ssrB, although the binding sites lie within the transcribed regions [4].
• The transcriptional activity of an sseA::luc fusion gene was shown to be dependent on ssrA, which is required for the expression of genes encoding components of the secretion system apparatus [5].
• Three wild-type strains of S. typhimurium, TML, HWSH, and SL1344, and two mutant strains, S. typhimurium SL1344 ssrA and S. typhimurium SL1344 msbB, consistently induced fluid accumulation in the lumen of loops and inflammation of loop-associated tissues [6].

Biological context of ssrA

• We have cloned and characterized the attachment site (att) of SopEPhi and found that its 47-bp core sequence overlaps the 3' terminus of the ssrA gene of serovar Typhimurium [2].

Anatomical context of ssrA

• Typhimurium strain and its hilA and ssrA mutants with porcine peripheral blood monocytes (PBM) [7].

Other interactions of ssrA

• Expression of sopD2 was induced inside host cells and was dependent on functional ssrA/B and phoP/Q, two component regulatory systems [8].

References