Related Experiment Video
Updated: Jun 26, 2025
11:28
Dissecting Host-virus Interaction in Lytic Replication of a Model Herpesvirus
Published on: October 7, 2011
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Exploiting bacterial effector proteins to uncover evolutionarily conserved antiviral host machinery
Aaron Embry1, Nina S Baggett1, David B Heisler1
1Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas, United State of America.
Plos Pathogens
|May 16, 2024
Summary
Researchers used bacterial proteins to discover host factors that restrict arbovirus replication. They identified SHOC2 and PSMC1 as ancient, conserved proteins that limit virus spread in insects and humans.
Area of Science:
- Virology
- Microbiology
- Host-Pathogen Interactions
Background:
- Arboviruses (arthropod-borne viruses) are significant global health threats.
- Identifying conserved host factors is crucial for understanding arbovirus host range and replication.
- Naturally abortive arbovirus infections in lepidopteran cells offer a unique model system.
Purpose of the Study:
- To uncover evolutionarily conserved host factors that restrict arbovirus replication.
- To utilize bacterial effector proteins as molecular tools to identify these host factors.
- To investigate the mechanisms by which bacterial effectors overcome host restriction.
Main Methods:
- Screening 210 bacterial effector proteins from seven pathogens against four arboviruses in lepidopteran cells.
- Identifying effectors that rescued arbovirus replication.
- Characterizing the E3 ubiquitin ligase activity of Shigella flexneri IpaH4.
- Assessing the impact of SHOC2 and PSMC1 depletion on arbovirus replication in insect and human cells.
Main Results:
- Several bacterial effectors were identified that promote replication of all four tested arboviruses.
- These effectors possess diverse enzymatic activities essential for breaking arbovirus restriction.
- Shigella flexneri IpaH4, an E3 ubiquitin ligase, degrades conserved host proteins SHOC2 and PSMC1.
- Depletion of SHOC2 or PSMC1 enhances arbovirus replication in both insect and human cells.
Conclusions:
- Bacterial effectors can be effectively used to discover conserved host antiviral machinery.
- SHOC2 and PSMC1 are ancient, conserved virus restriction factors important across diverse hosts.
- This study reveals novel effector functions and conserved roles for SHOC2 and PSMC1 in antiviral defense.
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