Fig. 2.

Regulator coupling property. If the transcription factors j and j ^′ are co-expressed (${\omega }_{j,j^{\prime }}$ is high, represented by a solid edge), and there exists at least one gene k that is not a TF, and is co-regulated by both j and j ^′, then the presence in the inferred graph of edge e _i,j is coupled with the presence of $e_{i,j^{\prime }}$