Ebola virus VP35 blocks stress granule assembly
Valerie Le Sage1, Alessandro Cinti2, Stephen McCarthy3
1HIV-1 RNA Trafficking Laboratory, Lady Davis Institute at the Jewish General Hospital, Montréal, Québec, Canada H3T 1E2.
Virology
|December 26, 2016
Summary
Ebola virus (EBOV) protein VP35 blocks stress granule (SG) assembly, a key part of antiviral immunity. This repression involves VP35
Area of Science:
- Cell biology
- Virology
- Immunology
Background:
- Stress granules (SGs) are cytoplasmic aggregates of silenced mRNAs, crucial for cellular stress responses and antiviral immunity.
- Viruses often manipulate SGs to evade host defenses.
Purpose of the Study:
- To investigate the role of Ebola virus (EBOV) infection and its proteins in SG assembly.
- To determine if EBOV interferes with cellular stress responses mediated by SGs.
Main Methods:
- Infection of cells with EBOV and transcription-competent virus-like particles (trVLPs).
- Induction of SGs using pharmacological stressors like arsenite.
- Co-immunoprecipitation assays to study protein interactions.
Main Results:
- EBOV infection and trVLPs blocked arsenite-induced SG assembly.
- EBOV protein VP35 repressed both canonical and non-canonical SG formation.
- The C-terminal domain of VP35 was partly responsible for SG repression.
- VP35 interacted with SG components (G3BP1, eIF3, eEF2) independently of stress and RNA.
Conclusions:
- EBOV VP35 actively represses cellular stress granule assembly.
- This represents a novel mechanism for EBOV to counteract innate antiviral immunity.
