SraL RNA
The SraL RNA ('sra' for small RNA), also known as RyjA, is a small non-coding RNA discovered in E. coli,{{Cite journal|last1=Argaman|first1=L.|last2=Hershberg|first2=R.|last3=Vogel|first3=J.|last4=Bejerano|first4=G.|last5=Wagner|first5=E. G.|last6=Margalit|first6=H.|last7=Altuvia|first7=S.|date=2001-06-26|title=Novel small RNA-encoding genes in the intergenic regions of Escherichia coli|journal=Current Biology|volume=11|issue=12|pages=941–950|issn=0960-9822|pmid=11448770|doi=10.1016/s0960-9822(01)00270-6|doi-access=free}}{{Cite journal|last1=Wassarman|first1=K. M.|last2=Repoila|first2=F.|last3=Rosenow|first3=C.|last4=Storz|first4=G.|last5=Gottesman|first5=S.|date=2001-07-01|title=Identification of novel small RNAs using comparative genomics and microarrays|journal=Genes & Development|volume=15|issue=13|pages=1637–1651|doi=10.1101/gad.901001|issn=0890-9369|pmid=11445539|pmc=312727}} and later in Salmonella Tiphimurium.{{Cite journal|last1=Viegas|first1=Sandra C.|last2=Pfeiffer|first2=Verena|last3=Sittka|first3=Alexandra|last4=Silva|first4=Inês J.|last5=Vogel|first5=Jörg|last6=Arraiano|first6=Cecília M.|date=2007|title=Characterization of the role of ribonucleases in Salmonella small RNA decay|journal=Nucleic Acids Research|volume=35|issue=22|pages=7651–7664|doi=10.1093/nar/gkm916|issn=1362-4962|pmc=2190706|pmid=17982174}}{{Cite journal|last1=Ortega|first1=Alvaro D.|last2=Gonzalo-Asensio|first2=Jesús|last3=García-del Portillo|first3=Francisco|date=April 2012|title=Dynamics of Salmonella small RNA expression in non-growing bacteria located inside eukaryotic cells|journal=RNA Biology|volume=9|issue=4|pages=469–488|doi=10.4161/rna.19317|issn=1555-8584|pmid=22336761|doi-access=free}} This ncRNA was found to be expressed only in stationary phase. It may possibly play a role in Salmonella virulence. The major stationary phase regulator RpoS is transcriptionally regulating SraL and directly binds to the sraL gene promoter. SraL down-regulates the expression of the ribosome-associated chaperone Trigger Factor (TF), which is involved in the folding of the newly synthesised cystolic proteins.{{Cite journal|last1=Silva|first1=Inês Jesus|last2=Ortega|first2=Alvaro Darío|last3=Viegas|first3=Sandra Cristina|last4=García-Del Portillo|first4=Francisco|last5=Arraiano|first5=Cecília Maria|date=September 2013|title=An RpoS-dependent sRNA regulates the expression of a chaperone involved in protein folding|journal=RNA|volume=19|issue=9|pages=1253–1265|doi=10.1261/rna.039537.113|issn=1469-9001|pmc=3753932|pmid=23893734}}