Figure 2From: Lessons from the modular organization of the transcriptional regulatory network of Bacillus subtilisCross-talk between modules. Master regulators (hubs) interconnect functional modules. At the higher levels, each master regulator is indicated. The color of each TF relates it to the module to which it belongs. We also show (top left) four disconnected groups that represent modules that are not interconnected by master regulators.Back to article page