Fig. 3.

Phylogenetic relationships and gene structures of RRA genes in Brassicaceae. (A) The unrooted tree is based on the similarity of RRA Rec domains constructed using the Neighbor–Joining method; the bar represents the relative divergence of the examined sequences. The subclades composed of RRAs potentially orthologous to individual A. thaliana RRA genes are presented using the same color; the subclades comprising homologs of the paired A. thaliana RRA genes, the result of an α WGD event (see the main text for details), are distinguished by different shades of a given color. The RRAs from individual species are distinguished by a triangle (BrRRAs), star (BoRRAS), and circle (BnRRAs). (B) A schematic representation of the A. thaliana and Brassica RRA gene structures (exons are depicted as boxes separated by introns as lines); the color code is used as in (A).