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Identification of Nucleolar Factors During HIV-1 Replication Through Rev Immunoprecipitation and Mass Spectrometry
Published on: June 26, 2019
Cell-surface nucleolin is sequestered into EPEC microcolonies and may play a role during infection
1Institute for Cell and Molecular Biosciences, Medical School, University of Newcastle, Framlington Place, Newcastle upon Tyne NE2 4HH, UK.
Microbiology (Reading, England)
|March 26, 2011
Summary
Enteropathogenic Escherichia coli (EPEC) hijacks host cell nucleolin, sequestering it into bacterial microcolonies to disrupt the epithelial barrier. Targeting nucleolin impairs EPEC
Area of Science:
- Microbiology
- Cell Biology
- Infectious Diseases
Background:
- Nucleolin is a key nucleolar protein involved in various cellular processes.
- Enteropathogenic Escherichia coli (EPEC) is a significant cause of bacterial diarrhea.
- EPEC infection leads to disruption of the intestinal epithelial barrier.
Purpose of the Study:
- To investigate the role of nucleolin in EPEC infection.
- To determine how EPEC interacts with nucleolin at the host cell surface.
- To assess the impact of nucleolin sequestration on EPEC's pathogenic mechanisms.
Main Methods:
- Utilized an intestinal cell model infected with EPEC.
- Tracked EGFP-tagged nucleolin localization during infection.
- Observed bacterial microcolony formation and nucleolin recruitment.
- Tested the effect of nucleolin-binding ligands on epithelial barrier function.
Main Results:
- EPEC recruits and sequesters cell-surface nucleolin into extracellular bacterial microcolonies.
- Nucleolin recruitment occurred in areas not associated with actin-based pedestals.
- Ligands targeting nucleolin reduced EPEC's disruption of epithelial barrier function.
- Bacterial attachment and pedestal formation remained unaffected by nucleolin targeting.
Conclusions:
- EPEC exploits both cytoplasmic and cell-surface pools of nucleolin during infection.
- Sequestration of cell-surface nucleolin is crucial for EPEC-mediated epithelial barrier disruption.
- Targeting nucleolin represents a potential therapeutic strategy against EPEC infections.
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