Gene Overlapping as a Modulator of Begomovirus Evolution
Iván Martín-Hernández1, Israel Pagán1,2
1Centro de Biotecnología y Genómica de Plantas UPM-INIA, 28223 Madrid, Spain.
Microorganisms
|February 25, 2022
Summary
Gene overlapping in begomoviruses, a type of plant virus, reduces mutation rates and slows evolution. This finding suggests gene overlapping influences virus evolution beyond RNA viruses, impacting genetic diversity.
Area of Science:
- Virology
- Genomics
- Evolutionary Biology
Background:
- RNA viruses exhibit high mutation rates and rapid evolution, with gene overlapping controlling mutational load.
- Some DNA viruses show evolutionary rates comparable to RNA viruses, often featuring extensive gene overlapping.
- Gene overlapping's role in modulating virus evolution beyond RNA viruses requires further investigation.
Purpose of the Study:
- To investigate the impact of gene overlapping on the evolutionary rates of DNA viruses.
- To test the hypothesis that gene overlapping influences virus evolution in the genus *Begomovirus*.
- To determine if gene overlapping affects mutation frequencies in begomoviruses.
Main Methods:
- Comparative genomic analysis of *Begomovirus* species.
- Assessment of gene overlapping patterns within the begomovirus genome.
- Quantification of synonymous and nonsynonymous mutation frequencies in relation to gene overlapping.
Main Results:
- Terminal gene overlapping was found to decrease the rate of begomovirus evolution.
- This decrease in evolutionary rate is associated with lower frequencies of both synonymous and nonsynonymous mutations.
- Non-terminal gene overlapping showed little effect on the pace of virus evolution.
Conclusions:
- Gene overlapping plays a significant role in shaping the evolution of begomoviruses.
- Terminal gene overlapping acts as a modulator of evolutionary rate and genetic diversity in these plant viruses.
- Findings provide novel insights into the factors governing virus evolution beyond the RNA world.
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