A complex interplay of evolutionary forces continues to shape ancient co-occurring symbiont genomes.

ABSTRACT: Many insects depend on ancient associations with intracellular bacteria for essential nutrition. The genomes of these bacteria are often highly reduced. Although drift is a major driver of symbiont evolution, other evolutionary forces continue to influence them. To understand how ongoing molecular evolution and gene loss shape symbiont genomes, we sequenced two of the most ancient symbionts known, Sulcia and Nasuia, from 20 Hawaiian Nesophrosyne leafhoppers. We leveraged the parallel divergence of Nesophrosyne lineages throughout Hawaii as a natural experimental framework. Sulcia and Nasuia experience ongoing-but divergent-gene loss, often in a convergent fashion. Although some genes are under relaxed selection, purifying and positive selection are

SUBMITTER: Vasquez YM 

PROVIDER: S-EPMC9379567 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature