Tracing dsDNA Virus-Host Coevolution through Correlation of Their G-Quadruplex-Forming Sequences

Area of Science:

• Genomics
• Virology
• Bioinformatics

Background:

• Gene expression regulation in viruses is crucial for their lifecycle.
• G-quadruplex structures are increasingly recognized for their roles in biological processes.
• Understanding viral genome organization is key to developing antiviral strategies.

Purpose of the Study:

• To analyze the occurrence and distribution of putative G-quadruplex-forming sequences (PQS) in viral dsDNA genomes.
• To investigate the correlation between PQS frequencies in viruses and their host organisms.
• To explore the potential of G-quadruplexes as therapeutic targets in viral infections.

Main Methods:

• Utilized the G4Hunter tool for analyzing PQS occurrence in viral dsDNA genomes.
• Compared PQS frequencies across different viral taxa and their corresponding hosts (archaea, bacteria, eukaryotes).
• Examined PQS localization within specific genomic regions, including introns and repeat regions.

Main Results:

• PQS frequencies varied across host taxa, independent of GC content.
• PQS were found in specific viral genomic regions, with notable differences in intron localization between eukaryotic and bacterial virus hosts.
• A significant positive correlation was observed between PQS frequencies in dsDNA viruses and their hosts, indicating coevolution.

Conclusions:

• Viral PQS occurrence is significantly influenced by host genomes, suggesting reciprocal evolutionary mimicry.
• The identified correlations highlight the potential of targeting G-quadruplexes for antiviral therapeutic development.
• Further research into virus-host coevolutionary dynamics of G-quadruplexes is warranted.