Representation of the 8-prenylnaringenin
and isoprenoid biosynthesis
pathways. Six A. thaliana genes were
overexpressed: PAL, phenylalanine ammonia lyase; C4H, cinnamate 4-hydroxylase;
CPR, cytochrome P450 reductase; 4CL, 4-coumarate-CoA ligase; CHS,
chalcone synthase; and CHI, chalcone isomerase; one gene from S. flavescens: FPT, flavonoid prenyltransferase;
one gene from R. capsulatus: TAL, tyrosine
ammonia lyase; and one truncated gene from S. cerevisiae: tHMG1, truncated 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase.
All enzyme names are in green. Dark blue arrows indicate the 8-prenylnaringenin
and isoprenoid biosynthesis pathways. The purple dashed arrow indicates
a route to the side-product phloretic acid, which is produced by the
catalytic activity of endogenous TSC13 (a double-bond reductase).
The green arrow indicates a truncated and deregulated copy of the
rate-limiting enzyme HMG-CoA reductase (tHMG1).