Cyclic di-GMP activation of polynucleotide phosphorylase signal-dependent RNA processing

J Mol Biol. 2011 Apr 15;407(5):633-9. doi: 10.1016/j.jmb.2011.02.019. Epub 2011 Feb 12.

Abstract

The second messenger cyclic diguanylic acid (c-di-GMP) is implicated in key lifestyle decisions of bacteria, including biofilm formation and changes in motility and virulence. Some challenges in deciphering the physiological roles of c-di-GMP are the limited knowledge about the cellular targets of c-di-GMP, the signals that control its levels, and the proportion of free cellular c-di-GMP, if any. Here, we identify the target and the regulatory signal for a c-di-GMP-responsive Escherichia coli ribonucleoprotein complex. We show that a direct c-di-GMP target in E. coli is polynucleotide phosphorylase (PNPase), an important enzyme in RNA metabolism that serves as a 3' polyribonucleotide polymerase or a 3'-to-5' exoribonuclease. We further show that a complex of polynucleotide phosphorylase with the direct oxygen sensors DosC and DosP can perform oxygen-dependent RNA processing. We conclude that c-di-GMP can mediate signal-dependent RNA processing and that macromolecular complexes can compartmentalize c-di-GMP signaling.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Cyclic GMP / analogs & derivatives*
  • Cyclic GMP / metabolism
  • Endoribonucleases / metabolism
  • Enzyme Activation
  • Escherichia coli / genetics
  • Escherichia coli / metabolism
  • Escherichia coli Proteins / genetics
  • Escherichia coli Proteins / metabolism
  • Heme / metabolism
  • Macromolecular Substances
  • Oxygen / metabolism
  • Phosphopyruvate Hydratase / metabolism
  • Polyribonucleotide Nucleotidyltransferase / metabolism*
  • RNA / genetics
  • RNA / metabolism*
  • Second Messenger Systems / physiology*

Substances

  • Escherichia coli Proteins
  • Macromolecular Substances
  • Heme
  • bis(3',5')-cyclic diguanylic acid
  • RNA
  • Polyribonucleotide Nucleotidyltransferase
  • Endoribonucleases
  • ribonuclease E
  • Phosphopyruvate Hydratase
  • Cyclic GMP
  • Oxygen