Figure 2.
Multiple and specialized flavone biosynthetic pathways. Purple path: Newly identified biosynthetic pathway for root-specific flavones in Scutellaria baicalensis. PAL: phenylalanine ammonia lyase; C4H: cinnamate-4-hydroxylase; 4CL: p-coumaroyl-CoA ligase; 4CL-like: cinnamic acid specific CoA ligase; CHS: chalcone synthase; CHI: chalcone isomerase; FNS: flavone synthase; F2H: flavanone-2-hydroxylase; F3′H: flavanone-3′-hydroxylase; F6H: flavanone-6-hydroxylase; OGT: O-glycosyltransferase; FOMT: flavonoid O-methyltransferase; CGT: C-glycosyltransferase; RHM: UDP-rhamnose synthase.
