Iron biofortification in rice by the introduction of multiple genes involved in iron nutrition
Hiroshi Masuda, Yasuhiro Ishimaru, May Sann Aung, Takanori Kobayashi, Yusuke Kakei, Michiko Takahashi, Kyoko Higuchi, Hiromi Nakanishi & Naoko K. Nishizawa
Scientific Reports 2, Article number: 543 doi:10.1038/srep00543
Received 08 May 2012 Accepted 29 June 2012 Published 30 July 2012
To address the problem of iron-deficiency anemia, one of the most prevalent human micronutrient deficiencies globally, iron-biofortified rice was produced using three transgenic approaches: by enhancing iron storage in grains via expression of the iron storage protein ferritin using endosperm-specific promoters, enhancing iron translocation through overproduction of the natural metal chelator nicotianamine, and enhancing iron flux into the endosperm by means of iron(II)-nicotianamine transporter OsYSL2 expression under the control of an endosperm-specific promoter and sucrose transporter promoter. Our results indicate that the iron concentration in greenhouse-grown T2 polished seeds was sixfold higher and that in paddy field-grown T3 polished seeds was 4.4-fold higher than that in non-transgenic seeds, with no defect in yield. Moreover, the transgenic seeds accumulated zinc up to 1.6-times in the field. Our results demonstrate that introduction of multiple iron homeostasis genes is more effective for iron biofortification than the single introduction of individual genes.
Agricultural geneticsPlant sciencesMolecular engineeringPlant biotechnology