Localization of iron in Arabidopsis seed requires the vacuolar membrane transporter VIT1.
Iron deficiency is a major human nutritional problem wherever plant-based diets are common. Using synchrotron x-ray fluorescence microtomography to directly visualize iron in Arabidopsis seeds, we show that iron is localized primarily to the provascular strands of the embryo. This localization is completely abolished when the vacuolar iron uptake transporter VIT1 is disrupted. Vacuolar iron storage is also critical for seedling development because vit1-1 seedlings grow poorly when iron is limiting. We have uncovered a fundamental aspect of seed biology that will ultimately aid the development of nutrient-rich seed, benefiting both human health and agricultural productivity.
Kim
Sun A
SA
Department of Biological Sciences, Dartmouth College, Hanover, NH 03755, USA.
Punshon
Tracy
T
Lanzirotti
Antonio
A
Li
Liangtao
L
Alonso
José M
JM
Ecker
Joseph R
JR
Kaplan
Jerry
J
Guerinot
Mary Lou
ML
D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D027682:Cation Transport Proteins / Q000235:genetics / Q000378:metabolism*; D018548:Cotyledon / Q000737:chemistry; D006706:Homeostasis; D018546:Hypocotyl / Q000737:chemistry; D007091:Image Processing, Computer-Assisted; D007425:Intracellular Membranes / Q000378:metabolism; D007501:Iron / Q000032:analysis / Q000378:metabolism*; D008345:Manganese / Q000032:analysis; D009154:Mutation; D019441:Plant Epidermis / Q000737:chemistry; D030821:Plants, Genetically Modified; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D036226:Seedlings / Q000254:growth & development; D012639:Seeds / Q000737:chemistry / Q000378:metabolism*; D014057:Tomography, X-Ray Computed; D014617:Vacuoles / Q000737:chemistry / Q000378:metabolism*; D015032:Zinc / Q000032:analysis
D029681:Arabidopsis Proteins; D027682:Cation Transport Proteins; D011993:Recombinant Fusion Proteins; C515257:VIT1 protein, Arabidopsis; D008345:Manganese; D007501:Iron; D015032:Zinc