A high-quality carrot genome assembly reveals new insights into carotenoid accumulation and Asterid genome evolution

IORIZZO, M.; ELLISON, S.; SENALIK, D.; ZENG, P.; PIMCHANOK, S.; BOWMAN, M.; IOVENE, M.; SANSEVERINO, W. ; CAVAGNARO, P. F.; YILDIZ, M.; MACKO-PODGORNI, A.; MORANSKA, E.; GRZEBELUS, E.; GRZEBELUS, D.; ASHRAFI, H.; ZHENG, Z.; CHENG, S.; SPOONER, D.M.; VAN DEYNZE, A.; SIMON, P. W.

NATURE GENETICS

NATURE PUBLISHING GROUP

Lugar: Londres; Año: 2016 vol. 40 p. 657 - 666

1061-4036

We report a high quality chromosome-scale assembly andanalysis of the carrot (Daucus carota)genome, the first sequenced genome to include a comparative evolutionaryanalysis among members of the Euasterid II clade. We characterized two newpolyploidization events, both occurring after the divergence of carrot frommembers of the Asterales order, clarifying the evolutionary scenario before andafter the radiation of the two main Asterid clades. Large- and small-scalelineage-specific duplications contributed to the expansion of gene familiesincluding those with roles in flowering time, defense response, flavor, andpigment accumulation. We identified a candidate gene, DCAR_032551, thatconditions carotenoid accumulation (Y)in carrot taproot, and is co-expressed with several isoprenoid biosyntheticgenes. The primary mechanism for carotenoid accumulation in carrot taproot isnot directly occurring at the biosynthetic level. We hypothesize thatDCAR_032551 regulates upstream photosystem development and functional processesincluding photomorphogenesis and root de-etiolation.