TY - JOUR
T1 - Mother-plant-mediated pumping of zinc into the developing seed
AU - Olsen, Lene Irene
AU - Hansen, Thomas Hesselhøj
AU - Laruelle, Camille
AU - Østerberg, Jeppe Thulin
AU - Hoffmann, Robert D
AU - Liesche, Johannes
AU - Krügel, Ute
AU - Surblé, Suzy
AU - Cadarsi, Stéphanie
AU - Samson, Vallerie Ann
AU - Grolimund, Daniel
AU - Husted, Søren
AU - Palmgren, Michael Broberg
PY - 2016/5/4
Y1 - 2016/5/4
N2 - Insufficient intake of zinc and iron from a cereal-based diet is one of the causes of 'hidden hunger' (micronutrient deficiency), which affects some two billion people1,2. Identifying a limiting factor in the molecular mechanism of zinc loading into seeds is an important step towards determining the genetic basis for variation of grain micronutrient content and developing breeding strategies to improve this trait3. Nutrients are translocated to developing seeds at a rate that is regulated by transport processes in source leaves, in the phloem vascular pathway, and at seed sinks. Nutrients are released from a symplasmic maternal seed domain into the seed apoplasm surrounding the endosperm and embryo by poorly understood membrane transport processes4'6. Plants are unique among eukaryotes in having specific P1B-ATPase pumps for the cellular export of zinc7. In Arabidopsis, we show that two zinc transporting P1B-ATPases actively export zinc from the mother plant to the filial tissues. Mutant plants that lack both zinc pumps accumulate zinc in the seed coat and consequently have vastly reduced amounts of zinc inside the seed. Blockage of zinc transport was observed at both high and low external zinc supplies. The phenotype was determined by the mother plant and is thus due to a lack of zinc pump activity in the seed coat and not in the filial tissues. The finding that P1B-ATPases are one of the limiting factors controlling the amount of zinc inside a seed is an important step towards combating nutritional zinc deficiency worldwide.
AB - Insufficient intake of zinc and iron from a cereal-based diet is one of the causes of 'hidden hunger' (micronutrient deficiency), which affects some two billion people1,2. Identifying a limiting factor in the molecular mechanism of zinc loading into seeds is an important step towards determining the genetic basis for variation of grain micronutrient content and developing breeding strategies to improve this trait3. Nutrients are translocated to developing seeds at a rate that is regulated by transport processes in source leaves, in the phloem vascular pathway, and at seed sinks. Nutrients are released from a symplasmic maternal seed domain into the seed apoplasm surrounding the endosperm and embryo by poorly understood membrane transport processes4'6. Plants are unique among eukaryotes in having specific P1B-ATPase pumps for the cellular export of zinc7. In Arabidopsis, we show that two zinc transporting P1B-ATPases actively export zinc from the mother plant to the filial tissues. Mutant plants that lack both zinc pumps accumulate zinc in the seed coat and consequently have vastly reduced amounts of zinc inside the seed. Blockage of zinc transport was observed at both high and low external zinc supplies. The phenotype was determined by the mother plant and is thus due to a lack of zinc pump activity in the seed coat and not in the filial tissues. The finding that P1B-ATPases are one of the limiting factors controlling the amount of zinc inside a seed is an important step towards combating nutritional zinc deficiency worldwide.
U2 - 10.1038/nplants.2016.36
DO - 10.1038/nplants.2016.36
M3 - Journal article
C2 - 27243644
SN - 2055-0278
VL - 2
JO - Nature Plants
JF - Nature Plants
M1 - 16036
ER -
