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Phage Phenomics: Physiological Approaches to Characterize Novel Viral Proteins
Published on: June 11, 2015
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Phage-encoded small RNA hijacks host replication machinery to support the phage lytic cycle
Aviezer Silverman1, Raneem Nashef1, Reut Wasserman1
1Department of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel.
Molecular Cell
|December 19, 2025
Summary
Bacteriophages (phages) utilize small RNAs (sRNAs) to regulate host bacteria during infection. A newly discovered phage sRNA, PreS, enhances DNA replication by targeting host genes, optimizing the phage lytic cycle.
Area of Science:
- Microbiology
- Molecular Biology
- Genetics
Background:
- Bacteriophages (phages) are crucial in regulating bacterial populations.
- Post-transcriptional regulation, particularly by small RNAs (sRNAs), is vital during phage infection but remains understudied.
- RNA chaperones like Hfq facilitate sRNA-mRNA interactions.
Purpose of the Study:
- To comprehensively map the in vivo RNA-RNA interaction network during phage lambda infection of Escherichia coli.
- To identify novel regulatory roles of sRNAs in phage-host interactions.
- To understand how phages modulate host machinery for replication.
Main Methods:
- Application of RNA interaction by ligation and sequencing (RIL-seq) to map RNA-RNA interactions.
- Analysis of the RNA interactome in E. coli during phage lambda infection.
- Identification and characterization of phage-encoded sRNAs.
Main Results:
- Extensive reprogramming of host-host, phage-phage, and interkingdom RNA-RNA interactions was observed.
- A phage-encoded sRNA, phage replication enhancer sRNA (PreS), was identified.
- PreS was shown to regulate essential host genes, including dnaN (DNA polymerase beta sliding clamp), enhancing DNA replication.
Conclusions:
- Phage infection involves a significant RNA-level regulatory layer impacting host-phage dynamics.
- Phage-encoded sRNAs can hijack host replication machinery to optimize the phage lytic cycle.
- The study reveals a novel mechanism of phage-host interaction mediated by sRNA regulation.
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