Exploring the History of Chloroplast Capture in Arabis Using Whole Chloroplast Genome Sequencing.

Chloroplast capture occurs when the chloroplast of one plant species is introgressed into another plant species. The phylogenies of nuclear and chloroplast markers from East Asian species are incongruent, which indicates hybrid origin and shows chloroplast capture. In the present study, the complete chloroplast genomes of , and were sequenced in order to analyze their divergence and their relationships. The chloroplast genomes of and were similar, which indicates chloroplast replacement. If hybridization causing chloroplast capture occurred once, divergence between recipient species would be lower than between donor species. However, the chloroplast genomes of species with possible hybrid origins, and differ at similar levels to possible maternal donor species which suggests that multiple hybridization events have occurred in their respective histories. The mitochondrial genomes exhibited similar patterns, while and were more similar to each other than to . This suggests that the two organellar genomes were co-transferred during the hybridization history of the East Asian species.