Extensive loss of RNA editing sites in rapidly evolving Silene mitochondrial genomes: selection vs. retroprocessing as the driving force.

ABSTRACT: Theoretical arguments suggest that mutation rates influence the proliferation and maintenance of RNA editing. We identified RNA editing sites in five species within the angiosperm genus Silene that exhibit highly divergent mitochondrial mutation rates. We found that mutational acceleration has been associated with rapid loss of mitochondrial editing sites. In contrast, we did not find a significant difference in the frequency of editing in chloroplast genes, which lack the mutation rate variation observed in the mitochondrial genome. As found in other angiosperms, the rate of substitution at RNA editing sites in Silene greatly exceeds the rate at synonymous sites, a pattern that has previously been interpreted as evidence for selection against RNA editing. Alternatively, we suggest that ed

SUBMITTER: Sloan DB 

PROVIDER: S-EPMC2927763 | biostudies-literature | 2010 Aug

REPOSITORIES: biostudies-literature