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Title: The maize PLASTID TERMINAL OXIDASE ( PTOX ) locus controls the carotenoid content of kernels
SUMMARY Carotenoids perform a broad range of important functions in humans; therefore, carotenoid biofortification of maize (Zea maysL.), one of the most highly produced cereal crops worldwide, would have a global impact on human health.PLASTID TERMINAL OXIDASE(PTOX) genes play an important role in carotenoid metabolism; however, the possible function ofPTOXin carotenoid biosynthesis in maize has not yet been explored. In this study, we characterized the maizePTOXlocus by forward‐ and reverse‐genetic analyses. While most higher plant species possess a single copy of thePTOXgene, maize carries two tandemly duplicated copies. Characterization of mutants revealed that disruption of either copy resulted in a carotenoid‐deficient phenotype. We identified mutations in thePTOXgenes as being causal of the classic maize mutant,albescent1. Remarkably, overexpression ofZmPTOX1significantly improved the content of carotenoids, especially β‐carotene (provitamin A), which was increased by ~threefold, in maize kernels. Overall, our study shows that maizePTOXlocus plays an important role in carotenoid biosynthesis in maize kernels and suggests that fine‐tuning the expression of this gene could improve the nutritional value of cereal grains.  more » « less
Award ID(s):
2129189
PAR ID:
10530517
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; ; ; ; ; ; « less
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
The Plant Journal
Volume:
118
Issue:
2
ISSN:
0960-7412
Page Range / eLocation ID:
457 to 468
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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