B1 — Daucus carota subsp. sativus

Summary

DCAR_020269 (DcB1) on carrot chromosome 6 encodes a beta-carotene 3-hydroxylase (EC 1.14.15.24), a member of the fatty acid hydroxylase family with iron-binding and hydrolase activity. The gene is associated with carotene metabolism, xanthophyll and carotenoid biosynthesis, and localises to the chloroplast membrane. In carrot, DcB1 has been linked to antioxidant capacity and carotenoid purity. It is also associated with root color, carotenoid content, drought tolerance, and with phenotypes including nonphotochemical quenching, tuber flesh color, flower pigmentation, carotenoid accumulation and hydroxylation, seed germination, and altered carotenoid profiles in seeds and leaves. Studies of related genes in other species link the family to xanthophyll and zeaxanthin content, lycopene accumulation, chlorophyll ratios, abscisic acid biosynthesis, antioxidant metabolism, chilling tolerance, and flowering time.