Carotenoid biosynthetic pathway in plants and gene copy number in carrot.

<p>IPP: isopentenyl diphosphate, DMAP: Dimethylallyl-diphosphate, IPI: Isopentenyl pyrophosphate isomerase, GGPS: Geranylgeranyl pyrophosphate synthase, PSY: Phytoene synthase, PDS: Phytoene desaturase, PTOX: Plastid terminal oxidase, CRTISO: Carotene isomerase, ZDS: ζ-carotene isomerase, LCYE: ε-lycopene cyclase, LCYB: β-lycopene cyclase, CHXB: β-carotene hydroxylase, CHXE: ε-carotene hydroxylase, ZEP: zeaxanthin epoxydase, VDE: violaxanthin de-epoxydase, NXS: Neoxanthin synthase, NCED: nine-<i>cis</i>-epoxycarotenoid dioxygenase, ABA: abscisic acid. Adapted from [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0116674#pone.0116674.ref025" target="_blank">25</a>] and [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0116674#pone.0116674.ref058" target="_blank">58</a>].