Origins and Evolution of WUSCHEL-Related Homeobox Protein Family in Plant Kingdom

Figure 4

Phylogenetic analysis of WOX family. A simplified version of the neighbor joining (NJ) tree, with 350 sequences of proteins from 50 species from green algae to angiosperms. The tree was divided into three clades. The three clades were the WUS clade, containing 166 sequences, 30 species; the intermediate clade, containing 86 sequences, 28 species; the ancient clade, containing 98 sequences, 47 species. The full phylogeny is shown in Supplementary Figure 3. In the inset, (A), (I), and (W) refer to the ancient clade, the intermediate clade, and the WUS clade. Two species (P. staeda and S. moellendorffii) have members in both ancient clade and intermediate clade; one species (P. hybieda) has members in both intermediate clade and WUS clade; six species (B. rapa, Gossypium hirsutum, P. sitchensis, R. sativus, Solanum tuberosum, and Vigna unguiculata) have members in both ancient clade and WUS clade; twenty-three species have members belonging to three clades. The species names are shown in Supplementary Table 2.