Fig. 2

Phylogenetic relationships, gene structure analysis, and motif distributions of Nicotiana tabacum L. bZIPs. bZIP: basic leucine zipper. a Phylogenetic tree constructed by the neighbour-joining method, with 1000 replicates on each node. b Amino acid motifs in the bZIP proteins (1–10) are represented by coloured boxes. Black lines indicate relative protein lengths. c Exons and introns are indicated by green rectangles, and grey lines, respectively