Natural genetic variation in lycopene epsilon cyclase tapped for maize biofortification.
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.
Harjes
Carlos E
CE
Institute for Genomic Diversity, Cornell University, Ithaca, NY 14853, USA.
Rocheford
Torbert R
TR
Bai
Ling
L
Brutnell
Thomas P
TP
Kandianis
Catherine Bermudez
CB
Sowinski
Stephen G
SG
Stapleton
Ann E
AE
Vallabhaneni
Ratnakar
R
Williams
Mark
M
Wurtzel
Eleanore T
ET
Yan
Jianbing
J
Buckler
Edward S
ES
D001483:Base Sequence; D001947:Breeding; D002338:Carotenoids / Q000032:analysis* / Q000378:metabolism; D003433:Crosses, Genetic; D065366:Cryptoxanthins; D018506:Gene Expression Regulation, Plant; D014644:Genetic Variation; D006239:Haplotypes; D019753:Intramolecular Lyases / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D016296:Mutagenesis; D009753:Nutritive Value; D011110:Polymorphism, Genetic; D040641:Quantitative Trait Loci; D024341:Xanthophylls / Q000032:analysis / Q000378:metabolism; D003313:Zea mays / Q000737:chemistry / Q000201:enzymology / Q000235:genetics*; D019207:beta Carotene / Q000032:analysis / Q000378:metabolism
D065366:Cryptoxanthins; D024341:Xanthophylls; D019207:beta Carotene; D002338:Carotenoids; C041635:alpha-carotene; D019753:Intramolecular Lyases; C070925:lycopene cyclase-isomerase