Class
Article
College
College of Science
Department
Biology Department
Faculty Mentor
Carol von Dohlen
Presentation Type
Poster Presentation
Abstract
Obligate symbionts play a crucial role in both the survival and evolution of their host. However, symbiont genomes degrade substantially over evolutionary time, sometimes losing genes presumed essential to the partnership. Buchnera aphidicola (Buchnera), the obligate nutritional symbiont of aphids, serves as a model for studying genomic degradation in obligate symbiotic systems. Previous literature has theorized that the patterns of Buchnera genome degradation may result partly from aphid gall formation, as galls generally have elevated levels of nutrients. However, the association of aphid life cycle type with patterns of Buchnera genome degradation has not been tested. To test this, I used genomic data from over 70 aphid species to investigate how different aphid life cycles are correlated with divergent patterns of Buchnera genome degradation. Contradicting previous theories regarding patterns of Buchnera genome degradation, I found that Buchnera of free-living, tree-feeding aphids have the most degraded genomes, not galling aphids. Buchnera of tree-feeding aphids were missing an average of 43% more genes than aphids of other life cycles and exhibit the most losses in specific functional categories.
Location
Logan, UT
Start Date
4-14-2021 12:00 AM
Included in
Consequences of Host Life Cycles for Symbiont Genome Evolution
Logan, UT
Obligate symbionts play a crucial role in both the survival and evolution of their host. However, symbiont genomes degrade substantially over evolutionary time, sometimes losing genes presumed essential to the partnership. Buchnera aphidicola (Buchnera), the obligate nutritional symbiont of aphids, serves as a model for studying genomic degradation in obligate symbiotic systems. Previous literature has theorized that the patterns of Buchnera genome degradation may result partly from aphid gall formation, as galls generally have elevated levels of nutrients. However, the association of aphid life cycle type with patterns of Buchnera genome degradation has not been tested. To test this, I used genomic data from over 70 aphid species to investigate how different aphid life cycles are correlated with divergent patterns of Buchnera genome degradation. Contradicting previous theories regarding patterns of Buchnera genome degradation, I found that Buchnera of free-living, tree-feeding aphids have the most degraded genomes, not galling aphids. Buchnera of tree-feeding aphids were missing an average of 43% more genes than aphids of other life cycles and exhibit the most losses in specific functional categories.