Exploration of the role of the non-coding RNA SbrE in L. monocytogenes stress response

Int J Mol Sci. 2012 Dec 24;14(1):378-93. doi: 10.3390/ijms14010378.

Abstract

SbrE is a ncRNA in Listeria monocytogenes, reported to be up-regulated by the alternative sigma factor σB. Initial quantitative RT-PCR (qRT-PCR) experiments on parent strains and isogenic ΔsigB strains demonstrated σB-dependent expression of SbrE across the four L. monocytogenes lineages and in L. innocua. Microarray and proteomics (MDLC/MS/MS with iTRAQ labeling) experiments with the L. monocytogenes parent strain and an isogenic ΔsbrE strain identified a single gene (lmo0636) and two proteins (Lmo0637 and Lmo2094) that showed lower expression levels in the ΔsbrE strain. qRT-PCR demonstrated an increase in SbrE transcript levels in stationary phase L. monocytogenes and in bacteria exposed to oxidative stress (mean log2 transcript levels 7.68 ± 0.57 and 1.70 ± 0.71 greater than in mid-log phase cells, respectively). However, no significant differences in growth or survival between the parent strain and ΔsbrE strain were confirmed under a variety of environmental stress conditions tested. Our data suggest that σB-dependent transcription of SbrE represents a conserved mechanism that contributes, across Listeria species, to fine-tuning of gene expression under specific environmental conditions that remain to be defined.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Gene Expression Regulation, Bacterial
  • Hydrogen-Ion Concentration
  • Listeria monocytogenes / genetics
  • Listeria monocytogenes / growth & development
  • Listeria monocytogenes / physiology*
  • Microbial Viability / genetics
  • Operon / genetics
  • Oxidative Stress / genetics
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • RNA, Untranslated / chemistry
  • RNA, Untranslated / genetics
  • RNA, Untranslated / metabolism*
  • Sigma Factor / metabolism
  • Stress, Physiological*

Substances

  • RNA, Messenger
  • RNA, Untranslated
  • Sigma Factor