Fig. 6.

Selection impacts within the glycoalkaloid biosynthetic pathway. Plant mevalonate pathway [modified from figure 1 in Ginzberg et al. (69) with permission from Springer] with branches into terpenoid, lanosterol, steroidal glycoalkaloid (SGA-specific pathway shaded in red), brassinosteroid, and phytosterol biosynthesis. Red arrows show pathways directly regulated by SQS and GAME9. Blue arrows show pathways controlled indirectly via GAME9 regulation of enzymes guiding substrates into the SGA-specific pathway.