Related Experiment Video
Updated: Aug 1, 2025
08:32
Dissecting Innate Immune Signaling in Viral Evasion of Cytokine Production
Published on: March 2, 2014
10.5K
Viral sponges sequester nucleotide signals to inactivate immunity
Desmond Richmond-Buccola1, Philip J Kranzusch1
1Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA; Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA 02115, USA.
Trends in Microbiology
|April 26, 2023
Summary
Bacteriophages use protein sponges to disable bacterial anti-phage defenses. These sponges bind to cyclic oligonucleotide signals, preventing bacteria from fighting off viral infections.
Area of Science:
- Microbiology
- Molecular Biology
- Immunology
Background:
- Bacteria possess sophisticated anti-phage defense mechanisms.
- These defenses rely on specialized nucleotide signals to identify and neutralize phages.
- Understanding phage countermeasures is crucial for controlling bacterial infections.
Purpose of the Study:
- To elucidate the mechanisms by which bacteriophages overcome bacterial antiviral immunity.
- To identify specific phage-encoded factors involved in evading host defenses.
- To characterize the interaction between phage proteins and bacterial immune signals.
Main Methods:
- Analysis of bacteriophage genomes for novel protein families.
- Biochemical assays to test protein-ligand interactions.
- In vitro and in vivo experiments to assess the impact of phage proteins on bacterial immunity.
Main Results:
- Discovery of bacteriophage-encoded protein 'sponges'.
- Demonstration that these sponges sequester bacterial cyclic oligonucleotide immune signals.
- Confirmation that sequestering these signals inactivates bacterial antiviral immunity.
Conclusions:
- Bacteriophages have evolved specific proteins to counteract bacterial defenses.
- Protein sponges represent a novel class of phage virulence factors.
- This finding sheds light on the co-evolutionary arms race between bacteria and phages.
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