Evolutionary relationships of R2R3-MYBs and validation of CmMYBs. A, Evolutionary relationships of 125 AtMYBs and 34 CmMYBs. Full-length amino acid sequences of R2R3-MYBs from the chrysanthemum transcriptome dataset and arabidopsis genome were first aligned using ClustalW in MEGA5. The phylogenetic tree was constructed according to the neighbour-joining method. Branches corresponding to partitions reproduced in less than 50% of the bootstrap replicates were collapsed. The evolutionary distances were computed using the p-distance method. All ambiguous positions were removed for each sequence pair. Evolutionary analyses were conducted in MEGA5. The black circle represents 34 CmMYBs. B, Phylogenetic tree of R2R3-MYBs and conserved motifs of chrysanthemum and other plants in subgroups 4, 5, 6 and 7. The black circle represents CmMYBs. Conserved motifs detected by MEME are listed behind each subgroup. C, Validation of CmMYBs in subgroups 4, 5, 6 and 7. The x-axis and y-axis represent the three developmental stages of the capitulum and the FPKM values, respectively. Red and black lines indicate the light and shading treatments, respectively.