Figure 4

The WRKY gene family of cowpea transcription factors. GSRs encoding the conserved WRKY domains were identified, the 79 WRKY genes were arbitrarily assigned names, and the conserved domains were aligned using ClustalW. An unrooted phylogenetic tree was produced using the PHYLIP program based on the neighbor-joining method and presented using PhyloDraw. The comparison includes a small number of Arabidopsis WRKY TF genes representative of each group. Cowpea WRKY genes are indicated by the prefix Vu, and Arabidopsis genes by the prefix At followed by their number and group. Groups are indicated by roman numerals. Group I sequences include both the N- and C-terminal domains (I NTF and I CTD, respectively); subgroup IIb* is an artifact in the ClustalW sequence alignment caused by the truncated nature of some of the domains. For additional information see Additional file 7 and Additional file 8.