RncO

Last updated
rncO
RF00552.jpg
Identifiers
SymbolrncO
Rfam RF00552
Other data
RNA type Cis-reg
Domain(s) Bacteria
SO SO:0000233
PDB structures PDBe

RncO is a bacterial non-coding RNA regulatory element found in the rnc leader sequence. The rnc operon is negatively auto-regulated by transcript stability. rnc, the first gene in the operon codes for RNase III which cleaves the long rncO stem II leading to transcript degradation and a reduction in translation. [1] Matsunaga et al. showed that RNase III cleavage can initiate rnc transcript decay independently of rnc gene translation. [2] Further work has established that rncO structure and function is conserved in Salmonella typhimurium . [3]

Contents

Structure

Functionally the first 215 nucleotides of the rnc leader have been shown to be sufficient. Within this region three stem-loops were identified. Stem-loop II is cleaved by RNase III, whereas stem-loops I and III are important for stability. [1]

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References

  1. 1 2 Matsunaga J, Simons EL, Simons RW (1996). "RNase III autoregulation: structure and function of rncO, the posttranscriptional "operator"". RNA. 2 (12): 1228–1240. PMC   1369450 . PMID   8972772.
  2. Matsunaga J, Simons EL, Simons RW (1997). "Escherichia coli RNase III (rnc) autoregulation occurs independently of rnc gene translation". Mol. Microbiol. 26 (5): 1125–1135. doi: 10.1046/j.1365-2958.1997.6652007.x . PMID   9426147. S2CID   25991176.
  3. Anderson PE, Matsunaga J, Simons EL, Simons RW (1996). "Structure and regulation of the Salmonella typhimurium rnc-era-recO operon". Biochimie. 78 (11–12): 1025–1034. doi:10.1016/S0300-9084(97)86726-0. PMID   9150881.