Fig. 2

Phylogenetic relationships and domain structures of the BBX genes. a. Phylogenetic analysis of BBX genes in Populus trichocarpa, A. thaliana, O. sativa, D. officinale and P. equestris, (b). Domain structures of the BBX proteins in D. officinale and P. equestris. CCT and BBX indicated CCT and B-BOX domains, respectively. c. A hypothetic model for the BBX evolutionary trajectory in D. officinale and P. equestris. B1, B2, CCT indicated B-Box 1, B-Box 2, and CCT domains, respectively