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Immunofluorescence Analysis of Stress Granule Formation After Bacterial Challenge of Mammalian Cells
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Immunofluorescence Analysis of Stress Granule Formation After Bacterial Challenge of Mammalian Cells

Published on: July 3, 2017

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Shigella induces stress granule formation by ADP-riboxanation of the eIF3 complex

Qinxin Zhang1, Wei Xian1, Zilin Li2

  • 1Department of Microbiology and Infectious Disease Center, NHC Key Laboratory of Medical Immunology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China.

Cell Reports
|February 18, 2024
PubMed

Insights

Pathogenic bacteria, Shigella flexneri, exploit host stress granules (SGs) by targeting translation factors. This SG formation aids bacterial replication and virulence, revealing a novel pathogenic mechanism.

Area of Science:

  • Cellular Biology
  • Microbiology
  • Pathogenesis

Background:

  • Stress granules (SGs) are cytoplasmic foci formed from translationally stalled mRNA and proteins under stress.
  • Viruses are known to hijack SGs for pathogenesis.
  • The role of SGs in bacterial pathogenesis was previously unknown.

Purpose of the Study:

  • To investigate whether pathogenic bacteria exploit stress granules for their benefit.
  • To elucidate the mechanism by which bacteria induce SG formation.
  • To determine the role of SG formation in bacterial virulence and replication.

Main Methods:

  • Studying Shigella flexneri infection models.
  • Analyzing the interaction of OspC effectors with host translation initiation factor 3 (eIF3).
  • Utilizing murine models of infection to assess bacterial virulence.

Main Results:

  • Shigella flexneri OspC proteins induce stress granule formation in infected host cells.
  • OspC effectors ADP-riboxylate eIF3 subunits, leading to translational arrest and SG assembly.
  • SG formation is beneficial for S. flexneri replication and bacterial strains lacking this ability are attenuated in virulence.

Conclusions:

  • Bacterial pathogens can induce SG assembly by inactivating host translational machinery.
  • Stress granules serve as a platform that promotes bacterial proliferation within host cells.
  • This study reveals a novel mechanism of bacterial pathogenesis involving host stress granules.
Keywords:
ADP-riboxanationCP: Molecular biologyOspCShigella flexnerieIF3stress granules

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