OxyS RNA is a small

non-coding RNA A non-coding RNA (ncRNA) is a functional RNA molecule that is not Translation (genetics), translated into a protein. The DNA sequence from which a functional non-coding RNA is transcribed is often called an RNA gene. Abundant and functionally im ...

which is induced in response to oxidative stress in ''

Escherichia coli ''Escherichia coli'' (),Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. also known as ''E. coli'' (), is a Gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus '' Esc ...

''. This RNA acts as a global regulator to activate or repress the expression of as many as 40 genes, by an

antisense In molecular biology and genetics, the sense of a nucleic acid molecule, particularly of a strand of DNA or RNA, refers to the nature of the roles of the strand and its complement in specifying a sequence of amino acids. Depending on the context ...

mechanism, including the fhlA-encoded transcriptional activator and the

rpoS The gene ''rpoS'' (RNA polymerase, sigma S, also called katF) encodes the sigma factor ''sigma-38'' (σ38, or RpoS), a 37.8 kD protein in ''Escherichia coli''. Sigma factors are proteins that regulate transcription in bacteria. Sigma factors ca ...

-encoded sigma(s) subunit of RNA polymerase. OxyS is bound by the

Hfq protein The Hfq protein (also known as HF-I protein) encoded by the ''hfq'' gene was discovered in 1968 as an ''Escherichia coli'' host factor that was essential for replication of the bacteriophage Qβ. It is now clear that Hfq is an abundant bacterial R ...

, that increases the OxyS RNA interaction with its target messages. Binding to Hfq alters the conformation of OxyS. The 109

nucleotide Nucleotides are organic molecules consisting of a nucleoside and a phosphate. They serve as monomeric units of the nucleic acid polymers – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of which are essential biomolecule ...

RNA is thought to be composed of three stem-loops.

Target genes

A number of additional targets were predicted and verified using microarray analysis. These are listed below: * yobF – confirmed by Northern analysis * yaiZ * rumA * wrbA – confirmed by Northern analysis * ybaY – confirmed by Northern analysis Furthermore, the mRNA encoded by the ''nusG'' gene is a direct target of OxyS.

References

External links

*
OxyS entry in the ncRNA database
Non-coding RNA {{molecular-cell-biology-stub