The Roles of Mutation, Selection, and Expression in Determining Relative Rates of Evolution in Mitochondrial versus Nuclear Genomes.

ABSTRACT: Eukaryotes rely on proteins encoded by the nuclear and mitochondrial (mt) genomes, which interact within multisubunit complexes such as oxidative-phosphorylation enzymes. Although selection is thought to be less efficient on the asexual mt genome, in bilaterian animals the ratio of nonsynonymous to synonymous substitutions (ω) is lower in mt- compared with nuclear-encoded OXPHOS subunits, suggesting stronger effects of purifying selection in the mt genome. Because high levels of gene expression constrain protein sequence evolution, one proposed resolution to this paradox is that mt genes are expressed more highly than nuclear genes. To test this hypothesis, we investigated expression and sequence evolution of mt and nuclear genes from 84 diverse eukaryotes that vary in mt gene content and

SUBMITTER: Havird JC 

PROVIDER: S-EPMC5100045 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature