The high-affinity metal Transporters NRAMP1 and IRT1 Team up to Take up Iron under Sufficient Metal Provision

被引：121

作者：

Castaings, Loren ^{[1
]}

Caquot, Antoine ^{[1
]}

Loubet, Stephanie ^{[1
]}

Curie, Catherine ^{[1
]}

机构：

[1] CNRS, Unite Mixte Rech 5004, Inst Biol Integrat Plantes, Lab Biochim & Physiol Mol Plantes, Montpellier, France

来源：

SCIENTIFIC REPORTS | 2016年 / 6卷

关键词：

ARABIDOPSIS-THALIANA; MANGANESE; ACQUISITION; HOMEOSTASIS; PROTEIN; PLANTS; ROOTS; PHOTOSYNTHESIS; INVOLVEMENT; STRATEGIES;

D O I：

10.1038/srep37222

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

Iron (Fe) and manganese (Mn) are essential metals which, when scarce in the growth medium, are respectively taken up by the root high affinity transporters IRT1 and NRAMP1 in Arabidopsis thaliana. The molecular bases for low affinity transport however remained unknown. Since IRT1 and NRAMP1 have a broad range of substrates among metals, we tested the hypothesis that they might be functionally redundant by generating nramp1 irt1 double mutants. These plants showed extreme Fe-deficiency symptoms despite optimal provision of the metal. Their phenotype, which includes low Fe and Mn contents and a defect of Fe entry into root cells as revealed by Fe staining, is rescued by high Fe supply. Using a promoter swap-based strategy, we showed that root endodermis retains the ability to carry out high affinity Fe transport and furthermore might be important to high-affinity Mn uptake. We concluded that NRAMP1 plays a pivotal role in Fe transport by cooperating with IRT1 to take up Fe in roots under replete conditions, thus providing the first evidence for a low affinity Fe uptake system in plants.

引用

页数：11