Fig. 7

Overall impact of ozone on terpenoid biosynthesis in northern red oak leaves. Leaves from seedlings exposed to ozone (mean FDR-adjusted p-values values of all ozone concentrations and exposure times); 3-Hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase is an ATP-dependent enzyme, necessary for biosynthesis of mevalonic acid, a key compound in isopentenyl diphosphate (IPP) formation. β-amyrin 11 oxidase, an essential cytochrome P450 enzyme, forms different terpenoid compounds through oxidation and glycosylation of β-amyrin. Geranylgeranyl pyrophosphate (GGDP) synthase adds IPP units to terpenoid skeleton to biosynthesize diverse types of terpenoids including mono-, di-, tri- and tetraterpenoids. Significance of expression patterns (FDR-adjusted p-value) are represented by color gradient, with upregulation and downregulation in red and blue colors, respectively. Bold and italic processes occur in plastids; underlined processes occur in cytosol; bold, italic, and underlined processes occur in either plastid or cytosol. MVA: mevalonic acid; MEP: methylerythritol phosphate