Figure 2.

Simplified model of the MeJA-mediated signaling cascade in Arabidopsis thaliana (A), nicotine biosynthesis in Nicotiana plants (B), terpenoid indole alkaloid biosynthesis in C. roseus (C) and isoquinoline alkaloid biosynthesis in C. japonica (D). Solid (blue) lines show transcriptional regulation and dotted (red) lines show post-translational regulation via protein-protein interaction. Arrows indicate activation and T-shaped lines indicate inhibition. The detailed regulation of gene expression is discussed in the text.