Evolutionary Stasis in Cycad Plastomes and the First Case of Plastome GC-Biased Gene Conversion.
Bottom Line: However, little has been known about the effect of gene conversion in the evolution of gymnosperm plastomes.In the IRs of cycad plastomes, the reduced substitution rates and GC-biased mutations are associated with a GC-biased gene conversion (gBGC) mechanism.We also propose a gBGC model to interpret the dissimilar evolutionary patterns as well as the compositionally biased mutations in the SC and IR regions of cycad plastomes.
Affiliation: Biodiversity Research Center, Academia Sinica, Taipei, Taiwan.Show MeSH
Related in: MedlinePlus
Mentions: Figure 3 illustrates the substitution rates estimated from all syntenic noncoding loci in the SC and IR regions, respectively. For each of the eight cycad genera, the substitution rates are significantly slower in the IR than in the SC regions (Mann–Whitney two-sided, all P < 0.01). Overall, the rates of SC regions are 2.11- to 2.39- folds higher than those of the IR regions across all cycad genera.Fig. 3.—
Affiliation: Biodiversity Research Center, Academia Sinica, Taipei, Taiwan.