Dual-Function RNAs

Microbiol Spectr. 2018 Sep;6(5):10.1128/microbiolspec.RWR-0032-2018. doi: 10.1128/microbiolspec.RWR-0032-2018.


Bacteria are known to use RNA, either as mRNAs encoding proteins or as noncoding small RNAs (sRNAs), to regulate numerous biological processes. However, a few sRNAs have two functions: they act as base-pairing RNAs and encode a small protein with additional regulatory functions. Thus, these so called "dual-function" sRNAs can serve as both a riboregulator and an mRNA. In some cases, these two functions can act independently within the same pathway, while in other cases, the base-pairing function and protein function act in different pathways. Here, we discuss the five known dual-function sRNAs-SgrS from enteric species, RNAIII and Psm-mec from Staphylococcus aureus, Pel RNA from Streptococcus pyogenes, and SR1 from Bacillus subtilis-and review their mechanisms of action and roles in regulating diverse biological processes. We also discuss the prospect of finding additional dual-function sRNAs and future challenges in studying the overlap and competition between the functions.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, N.I.H., Intramural
  • Review

MeSH terms

  • Bacillus subtilis / genetics
  • Bacteria / genetics
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Base Pairing / genetics
  • Escherichia coli Proteins / genetics
  • Escherichia coli Proteins / metabolism
  • Gene Expression Regulation, Bacterial*
  • RNA, Bacterial / genetics*
  • RNA, Bacterial / metabolism*
  • RNA, Messenger / genetics*
  • RNA, Messenger / metabolism*
  • RNA, Small Untranslated / genetics*
  • RNA, Small Untranslated / metabolism*
  • Staphylococcus aureus / genetics
  • Streptococcus pyogenes / genetics


  • Bacterial Proteins
  • Escherichia coli Proteins
  • RNA, Bacterial
  • RNA, Messenger
  • RNA, Small Untranslated
  • RNAIII, Staphylococcus aureus
  • SgrT protein, E coli