Figure 4.

Co-regulatory networks of Arabidopsis WRKY genes. For each pair of WRKY genes, the Pearson Coefficient was calculated on untransformed values P-lin (see Panel A) and on log-transformed values P-log (see Panel B) to measure the correlation of expression levels, based on 2,000 Arabidopsis microarray experiments. Each pair of correlated WRKY genes (Pearson Correlation Coefficient value higher than 0.6) are shown in the figure with an edge connecting them. The thickness of the edges is proportional to the value of the Pearson Correlation Coefficient. Thick black line: Pearson Correlation Coefficient 0.96; Thin black line: Pearson Correlation Coefficient 0.6. Proximity of two genes on the graph is not indicative of their relatedness. The colours indicate different phylogenetic groups. See Additional files 5 and 6 for the specific numeric values of the P-lin and P-log correlation coefficient, respectively. The four identified co-regulatory neworks were indicated as: COR-A, COR-B, COR-C and COR-D.