The SdsR/RyeB RNA is a non-coding RNA that was identified in a large scale screen of E. coli. The exact 5â² and 3â² ends of this RNA are uncertain. This RNA overlaps the SraC/RyeA RNA on the opposite strand suggesting that the two may act in a concerted manner. It is transcribed by general stress factor ÃÂ<sup>s</sup> and is most highly expressed in stationary phase. SdsR/RyeB RNA interacts with Hfq.
The homologous sRNA in S. enterica was shown to regulate synthesis of major porin OmpD. A study using Salmonella identified 20 targets of this sRNA including transcriptional regulator, CRP, global DNA-binding factors, StpA and HupB, the antibiotic transporter protein, TolC, and the RtsA/B two-component system (TCS), and validated their post-transcriptional control by SdsR/RyeB RNA.