FIGURE 4.

Essential factors promoting AN biosynthesis. Endogenous and exogenous factors that positively affect AN biosynthesis. Different abiotic factors inducing plant defense, trichome proliferation and, consequently, AN production. Seven transcription factors have been identified so far in the positive regulation of any of the AN pathway enzymes. Plant hormones ABA, GA, JA, and SA also positively affect both trichome proliferation and artemisinin biosynthesis. Dashed, colored arrows indicate TFs that directly regulate hormone biosynthetic pathways.