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Updated: Jun 16, 2025
09:40
Phage Phenomics: Physiological Approaches to Characterize Novel Viral Proteins
Published on: June 11, 2015
12.1K
Prevalence of Group II Introns in Phage Genomes
Liana N Merk1,2,3, Thomas A Jones1,2, Sean R Eddy1,2
1Department of Molecular and Cellular Biology, Harvard University, 02138, Cambridge, USA.
Biorxiv : the Preprint Server for Biology
|June 6, 2025
Summary
Group II introns, mobile genetic elements, are now found widely in diverse bacteriophages. This discovery challenges previous assumptions about their absence in phage genomes.
Area of Science:
- Molecular Biology
- Virology
- Genomics
Background:
- Bacteriophage genomes are typically dense with genes due to strong selective pressures.
- Mobile genetic elements (MGEs), such as group II introns, can invade these genomes.
- Group II introns are known in bacteria, archaea, and eukaryotes but were thought to be absent in phages.
Purpose of the Study:
- To investigate the prevalence of group II introns in bacteriophage genomes.
- To overcome challenges in identifying group II introns based on sequence similarity alone.
Main Methods:
- Utilized advances in RNA structure-based homology searches.
- Employed covariance models to identify conserved secondary structures of group II introns.
- Analyzed genome sequences from diverse phage groups.
Main Results:
- Discovered widespread presence of group II introns across various bacteriophage types.
- Identified group II introns in phages from endosymbionts to large jumbophages.
- Demonstrated the effectiveness of structure-based methods for intron identification.
Conclusions:
- Group II introns are a common feature in a wide range of bacteriophages.
- This finding expands our understanding of MGEs in viral genomes.
- Future research should consider the impact and evolution of group II introns in phages.
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