Figure 2

A combined set of links with the highest change in functional activity between patients with AML versus patients with ALL. To identify differential transcriptional activities between networks obtained from two sample populations, we analyzed the data matrix whose columns represent the individual adjacency networks and whose rows represent TF-gene link activities across the samples. Entries of this matrix can take one of three values; activation (1), inhibition (-1), no effect or undetermined relationship (0). The graph shown summarizes the output from a feature selection procedure (see methods section) for identifying the TF-gene regulatory links that have the most prominent differential transcriptional activities between AML and ALL patients. Target genes are denoted by yellow circles and TFs by red squares. Stimulatory and inhibitory regulatory links, are indicated by red and blue arrows respectively.