Fig. 2

Phylogenetic relationships, DNA-binding types, intron insertion patterns, and architecture of conserved protein motifs in 35 bHLH subfamilies. a Phylogenetic relationships of 769 bHLHs from B. napus (602) and Arabidopsis (167). The phylogenetic tree is generated based on the alignment of bHLH domains of the corresponding bHLH proteins with 1000 bootstrap replicates. The subfamilies marked in grey are newly identified in this study as compared to the results in Arabidopsis [7]. b DNA-binding types and intron insertion types of BnabHLHs in each subfamily. The illustration of intron insertion patterns is shown in Fig. 3. c Architecture of conserved protein motifs of BnabHLHs in each subfamily by MEME analysis. Blocks with a black background indicate the bHLH domain. Blocks with a solid line represent the motif distributed in all proteins in a certain subfamily, while those with a dotted line represent the motif distributed in a part of members in a given subfamily