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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
Summary
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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