Related Experiment Video
Updated: May 31, 2026
04:52
Following the Dynamics of Structural Variants in Experimentally Evolved Populations
Published on: February 3, 2023
Intrahost mutational dynamics parallel long-term genome evolution in endosymbionts
Younghwan Kwak1, Gordon Bennett1
1Department of Life and Environmental Sciences, University of California, Merced, CA, USA.
Molecular Biology and Evolution
|May 29, 2026
Summary
Insect endosymbionts show genetic variation within hosts, revealing distinct mutation patterns that drive genome evolution. These findings illuminate microevolutionary processes shaping obligate bacterial genomes.
Area of Science:
- Microbiology
- Evolutionary Biology
- Genomics
Background:
- Obligate insect endosymbionts exhibit rapid genome evolution, including accelerated molecular evolution and gene loss.
- The microevolutionary forces driving these genomic changes at the intrahost population level are poorly understood.
Purpose of the Study:
- To investigate intrahost genetic diversity and mutational dynamics of Karelsulcia and Nasuia endosymbionts in the aster leafhopper.
- To link intrahost evolutionary processes to long-term genome-wide evolutionary trends in insect endosymbionts.
Main Methods:
- Sequencing and analysis of intrahost genetic variation in Karelsulcia and Nasuia.
- Comparison of intrahost mutation patterns with long-term evolutionary changes.
Main Results:
- Both endosymbionts displayed measurable intrahost genetic variation, challenging the assumption of strict clonality.
- Karelsulcia variation was dominated by repeat-associated indels, while Nasuia showed single-nucleotide mutations influencing AT bias.
- Observed intrahost mutational patterns mirrored long-term sequence changes in endosymbiont genomes.
Conclusions:
- Distinct intrahost mutational processes significantly drive macroevolutionary patterns in endosymbiont genomes.
- Laboratory systems with insect endosymbionts offer a valuable model for studying fundamental evolutionary mechanisms.
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