Disruption of OsSULTR3;3 Reduces Phytate and Phosphorus Concentrations and Alters the Metabolite Profile in Rice Grains

New Phytol. 2016 Aug;211(3):926-39. doi: 10.1111/nph.13969. Epub 2016 Apr 25.


Two low phytic acid (lpa) mutants have been developed previously with the aim to improve the nutritional value of rice (Oryza sativa) grains. In the present study, the impacts of lpa mutations on grain composition and underlying molecular mechanisms were investigated. Comparative compositional analyses and metabolite profiling demonstrated that concentrations of both phytic acid (PA) and total phosphorus (P) were significantly reduced in lpa brown rice, accompanied by changes in other metabolites and increased concentrations of nutritionally relevant compounds. The lpa mutations modified the expression of a number of genes involved in PA metabolism, as well as in sulfate and phosphate homeostasis and metabolism. Map-based cloning and complementation identified the underlying lpa gene to be OsSULTR3;3. The promoter of OsSULTR3;3 is highly active in the vascular bundles of leaves, stems and seeds, and its protein is localized in the endoplasmic reticulum. No activity of OsSULTR3;3 was revealed for the transport of phosphate, sulfate, inositol or inositol 1,4,5 triphosphate by heterologous expression in either yeast or Xenopus oocytes. The findings reveal that OsSULTR3;3 plays an important role in grain metabolism, pointing to a new route to generate value-added grains in rice and other cereal crops.

Keywords: anti-nutrient; metabolite profiling; phosphate transporter; phosphorus; phytic acid; rice (Oryza sativa); sulfate transporter; γ-aminobutyric acid.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anion Transport Proteins / metabolism*
  • Biological Transport
  • Chromosome Mapping
  • Cloning, Molecular
  • Endoplasmic Reticulum / metabolism
  • Gene Expression Regulation, Plant
  • Genes, Plant
  • Glucuronidase / metabolism
  • Metabolic Networks and Pathways
  • Metabolome
  • Metabolomics*
  • Mutation / genetics
  • Oryza / genetics
  • Oryza / metabolism*
  • Phosphorus / metabolism*
  • Phytic Acid / biosynthesis
  • Phytic Acid / metabolism*
  • Plant Proteins / metabolism*
  • Plant Vascular Bundle / metabolism
  • Seeds / metabolism*
  • Subcellular Fractions / metabolism
  • Sulfates / metabolism
  • Sulfur / metabolism


  • Anion Transport Proteins
  • Plant Proteins
  • Sulfates
  • Phosphorus
  • Sulfur
  • Phytic Acid
  • Glucuronidase

Associated data

  • GENBANK/KT188441
  • GENBANK/KT188442
  • GENBANK/KT188443
  • GENBANK/KT188444
  • GENBANK/KT188446
  • GENBANK/KT188447
  • GENBANK/U12639.1