Phylogenetic analysis and gene structure of TcBBM. A. Phylogenetic analysis of AP2 gene family. The neighbor-joining consensus tree was constructed based on the full-length amino acid sequences of AP2 gene family [13,33]. The scale bar represents 0.1 substitutions per site and the values next to the nodes are the bootstrap values from 2000 replicates. B. Gene models of BBM genes of Theobroma cacao (Tc), Arabidopsis thaliana (At) and Brassica napus (Bn) are depicted by their exons (blocks) and introns (lines). The exons highlighted by the dotted lines represent the two AP2 domains, connected by the linker highlighted by the dashed lines. C. Alignment of the two AP2 domain repeats connected by a linker characteristic of AP2-ERF BBM genes from Theobroma cacao (Tc), Arabidopsis thaliana (At) and Brassica napus (Bn). At = Arabidopsis thaliana, Bn = Brassica napus, Gm = Glycine max, Mt = Medicago truncatula, Os = Oryza sativa, Vv = Vitis vinifera, Zm = Zea mays. BBM = BABY BOOM, AIL = AINTEGUMENTA-LIKE, ANT = AINTEGUMENTA, PLT2 = PLETHORA.