These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Escherichia coli ribonuclease III activity is downregulated by osmotic stress: consequences for the degradation of bdm mRNA in biofilm formation.
    Author: Sim SH, Yeom JH, Shin C, Song WS, Shin E, Kim HM, Cha CJ, Han SH, Ha NC, Kim SW, Hahn Y, Bae J, Lee K.
    Journal: Mol Microbiol; 2010 Jan; 75(2):413-25. PubMed ID: 19943899.
    Abstract:
    During the course of experiments aimed at identifying genes with ribonuclease III (RNase III)-dependent expression in Escherichia coli, we found that steady state levels of bdm mRNA were dependent on cellular concentrations of RNase III. The half-lives of adventitiously overexpressed bdm mRNA and the activities of a transcriptional bdm'-'cat fusion were observed to be dependent on cellular concentrations of RNase III, indicating the existence of cis-acting elements in bdm mRNA responsive to RNase III. In vitro and in vivo cleavage analyses of bdm mRNA identified two RNase III cleavage motifs, one in the 5'-untranslated region and the other in the coding region of bdm mRNA, and indicated that RNase III cleavages in the coding region constitute a rate-determining step for bdm mRNA degradation. We also discovered that downregulation of the ribonucleolytic activity of RNase III is required for the sustained elevation of RcsB-induced bdm mRNA levels during osmotic stress and that cells overexpressing bdm form biofilms more efficiently. These findings indicate that the Rcs signalling system has an additional regulatory pathway that functions to modulate bdm expression and consequently, adapt E. coli cells to osmotic stress.
    [Abstract] [Full Text] [Related] [New Search]