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The enteropathogenic E. coli effector EspF targets and disrupts the nucleolus by a process regulated by mitochondrial

Paul Dean1, Jon A Scott, Andrew A Knox

  • 1Institute for Cell and Molecular Biosciences, Medical School, University of Newcastle, Newcastle upon Tyne, United Kingdom. p.dean@ncl.ac.uk

Plos Pathogens
|June 30, 2010
PubMed

Insights

Enteropathogenic E. coli (EPEC) uses the effector protein EspF to target the nucleolus, disrupting key factors like nucleolin. This reveals a sophisticated bacterial strategy for controlling virulence during infection.

Area of Science:

  • Cell Biology
  • Microbiology
  • Virology

Background:

  • The nucleolus is a vital nuclear structure responsible for ribosome biogenesis in eukaryotic cells.
  • Nucleolar disruption is a characteristic feature observed in infections by most viruses.
  • The role of nucleolar disruption in bacterial pathogenesis is less understood.

Purpose of the Study:

  • To investigate the specific mechanisms by which the enteropathogenic E. coli (EPEC) effector protein EspF targets and disrupts the nucleolus.
  • To elucidate the role of nucleolar disruption in bacterial pathogenesis.
  • To uncover novel regulatory mechanisms controlling bacterial effector protein targeting.

Main Methods:

  • Bio-imaging techniques to visualize protein localization and cellular structures.
  • Genetic analyses to study the function of specific bacterial proteins and pathways.
  • Biochemical assays to analyze protein interactions and cellular processes.

Main Results:

  • The EPEC effector protein EspF specifically targets the nucleolus, driven by its N-terminal domain.
  • EspF causes the loss of nucleolin, the most abundant nucleolar protein, from the nucleolus.
  • Bacterial species can disrupt the nucleolus, contingent on their ability to deliver effector proteins.
  • EspF's nucleolar targeting is regulated by EPEC's manipulation of host mitochondria.

Conclusions:

  • The nucleolus is a potential common target in bacterial pathogenesis.
  • Bacterial pathogens have evolved sophisticated mechanisms for spatio-temporal control of virulence proteins.
  • EspF-mediated nucleolar disruption represents a novel virulence strategy for EPEC.

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