Molecules and Cells

, Volume 33, Issue 3, pp 269–275 | Cite as

Activation of Rice nicotianamine synthase 2 (OsNAS2) enhances iron availability for biofortification

  • Sichul Lee
  • You-Sun Kim
  • Un Sil Jeon
  • Yoon-Keun Kim
  • Jan K. Schjoerring
  • Gynheung An


Because micronutrients in human diets ultimately come from plant sources, malnutrition of essential minerals is a significant public health concern. By increasing the expression of nicotianamine synthase (NAS), we fortified the level of bioavailable iron in rice seeds. Activation of iron deficiency-inducible OsNAS2 resulted in a rise in Fe content (3.0-fold) in mature seeds. Its ectopic expression also increased that content. Enhanced expression led to higher tolerance of Fe deficiency and better growth under elevated pH. Mice fed with OsNAS2-D1 seeds recovered more rapidly from anemia, indicating that bioavailable Fe contents were improved by this increase in OsNAS2 expression.


anemia bioavailability mouse rice 


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Copyright information

© The Korean Society for Molecular and Cellular Biology and Springer Netherlands 2012

Authors and Affiliations

  • Sichul Lee
    • 1
  • You-Sun Kim
    • 2
  • Un Sil Jeon
    • 3
  • Yoon-Keun Kim
    • 2
  • Jan K. Schjoerring
    • 4
  • Gynheung An
    • 5
  1. 1.Department of Biological SciencesDartmouth CollegeHanoverUSA
  2. 2.Department of Life SciencePohang University of Science and TechnologyPohangKorea
  3. 3.Department of Internal MedicineKorea University Guro HospitalSeoulKorea
  4. 4.Plant and Soil Science Laboratory, Department of Agriculture and Ecology, Faculty of Life SciencesUniversity of CopenhagenFrederiksberg CDenmark
  5. 5.Department of Plant Molecular Systems Biotechnology and Crop Biotech CenterKyung Hee UniversityYonginKorea

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