Activation of rice Yellow Stripe1-Like 16 (OsYSL16) enhances iron efficiency.
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.
Department of Biological Sciences, Dartmouth College, Hanover, NH, USA.
Sichul
S
Lee
Nayeon
N
Ryoo
Jong-Seong
JS
Jeon
Mary Lou
ML
Guerinot
Gynheung
G
An
D018506:Gene Expression Regulation, Plant; D017930:Genes, Reporter / Q000235:genetics; D005966:Glucuronidase / Q000235:genetics; D049452:Green Fluorescent Proteins / Q000235:genetics; D006706:Homeostasis / Q000235:genetics; D007501:Iron / Q000378:metabolism*; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*; D009928:Organ Specificity; D012275:Oryza / Q000235:genetics / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D018517:Plant Roots / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified; D021381:Protein Transport
D026901:Membrane Transport Proteins; D010940:Plant Proteins; D049452:Green Fluorescent Proteins; D007501:Iron; D005966:Glucuronidase