 Figure 2: Two examples of network motifs, the coherent and incoherent feedforward loop (cFFL and iFFL). The diagrams represent the regulation of a gene Z, via a direct path between a transcription factor X to Z, and an indirect connection from X via another gene or transcription factor Y to Z. Arrows represent gene activation (+) and a vertical bar inactivation (-). In a coherent feedforward loop (cFFL), all connections are activating. In the incoherent feedforward loop (iFFL), the path from Y to Z inhibites gene expression. (Adapted from Alon 2007: 47).