AUTHOR=Walden Nora , Nguyen Thu-Phuong , Mandáková  Terezie , Lysak Martin A. , Schranz Michael Eric 

TITLE=Genomic Blocks in Aethionema arabicum Support Arabideae as Next Diverging Clade in Brassicaceae

JOURNAL=Frontiers in Plant Science

VOLUME=11

YEAR=2020

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2020.00719

DOI=10.3389/fpls.2020.00719

ISSN=1664-462X

ABSTRACT=<p>The tribe Aethionemeae is sister to all other crucifers, making it a crucial group for unraveling genome evolution and phylogenetic relationships within the crown group Brassicaceae. In this study, we extend the analysis of Brassicaceae genomic blocks (GBs) to <italic>Aethionema</italic> whereby we identified unique block boundaries shared only with the tribe Arabideae. This was achieved using bioinformatic methods to analyze synteny between the recently updated genome sequence of <italic>Aethionema arabicum</italic> and other high-quality Brassicaceae genome sequences. We show that compared to the largely conserved genomic structure of most non-polyploid Brassicaceae lineages, GBs are highly rearranged in <italic>Aethionema</italic>. Furthermore, we detected similarities between the genomes of <italic>Aethionema</italic> and <italic>Arabis alpina</italic>, in which also a high number of genomic rearrangements compared to those of other Brassicaceae was found. These similarities suggest that tribe Arabideae, a clade showing conflicting phylogenetic position between studies, may have diverged before diversification of the other major lineages, and highlight the potential of synteny information for phylogenetic inference.</p>