Activation of rice Yellow Stripe1-Like 16 (OsYSL16) enhances iron efficiency

Mol Cells. 2012 Feb;33(2):117-26. doi: 10.1007/s10059-012-2165-9. Epub 2012 Jan 3.

Abstract

Graminaceous plants release ferric-chelating phytosiderophores that bind to iron. These ferric-phytosiderophore complexes are transported across the plasma membrane by a protein produced from Yellow Stripe 1 (YS1). Here, we report the characterization of OsYSL16, one of the YS1-like genes in rice. Real-time analysis revealed that this gene was constitutively expressed irrespective of metal status. Promoter fusions of OsYSL16 to β-glucuronidase (GUS) showed that OsYSL16 was highly expressed in the vascular tissues of the root, leaf, and spikelet, and in leaf mesophyll cells. The OsYSL16-green fluorescence protein (GFP) fusion protein was localized to the plasma membrane. From a pool of rice T-DNA insertional lines, we identified two independent activation-tagging mutants in OsYSL16. On an Fe-deficient medium, those mutants retained relatively high chlorophyll concentrations compared with the wild-type (WT) controls, indicating that they are more tolerant to a lack of iron. The Fe concentration in shoots was also higher in the OsYSL16 activation lines than in the WT. During germination, the rate of Fe-utilization from the seeds was higher in the OsYSL16 activation lines than in the WT seeds. Our results suggest that the function of OsYSL16 in Fe-homeostasis is to enable distribution of iron within a plant.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Gene Expression Regulation, Plant
  • Genes, Reporter / genetics
  • Glucuronidase / genetics
  • Green Fluorescent Proteins / genetics
  • Homeostasis / genetics
  • Iron / metabolism*
  • Membrane Transport Proteins / genetics
  • Membrane Transport Proteins / metabolism*
  • Organ Specificity
  • Oryza / genetics
  • Oryza / metabolism*
  • Plant Proteins / genetics
  • Plant Proteins / metabolism*
  • Plant Roots / genetics
  • Plant Roots / metabolism*
  • Plants, Genetically Modified
  • Protein Transport

Substances

  • Membrane Transport Proteins
  • Plant Proteins
  • Green Fluorescent Proteins
  • Iron
  • Glucuronidase