1. Natural genetic variation in lycopene epsilon cyclase tapped for maize biofortification.
- Author
-
Harjes CE, Rocheford TR, Bai L, Brutnell TP, Kandianis CB, Sowinski SG, Stapleton AE, Vallabhaneni R, Williams M, Wurtzel ET, Yan J, and Buckler ES
- Subjects
- Base Sequence, Breeding, Carotenoids metabolism, Crosses, Genetic, Cryptoxanthins, Gene Expression Regulation, Plant, Haplotypes, Intramolecular Lyases metabolism, Molecular Sequence Data, Mutagenesis, Nutritive Value, Polymorphism, Genetic, Quantitative Trait Loci, Xanthophylls analysis, Xanthophylls metabolism, Zea mays chemistry, Zea mays enzymology, beta Carotene analysis, beta Carotene metabolism, Carotenoids analysis, Genetic Variation, Intramolecular Lyases genetics, Zea mays genetics
- Abstract
Dietary vitamin A deficiency causes eye disease in 40 million children each year and places 140 to 250 million at risk for health disorders. Many children in sub-Saharan Africa subsist on maize-based diets. Maize displays considerable natural variation for carotenoid composition, including vitamin A precursors alpha-carotene, beta-carotene, and beta-cryptoxanthin. Through association analysis, linkage mapping, expression analysis, and mutagenesis, we show that variation at the lycopene epsilon cyclase (lcyE) locus alters flux down alpha-carotene versus beta-carotene branches of the carotenoid pathway. Four natural lcyE polymorphisms explained 58% of the variation in these two branches and a threefold difference in provitamin A compounds. Selection of favorable lcyE alleles with inexpensive molecular markers will now enable developing-country breeders to more effectively produce maize grain with higher provitamin A levels.
- Published
- 2008
- Full Text
- View/download PDF