The high-affinity metal Transporters NRAMP1 and IRT1 Team up to Take up Iron under Sufficient Metal Provision.
Sci Rep
; 6: 37222, 2016 11 16.
Article
in En
| MEDLINE
| ID: mdl-27849020
ABSTRACT
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.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Cation Transport Proteins
/
Arabidopsis Proteins
/
Metals
Language:
En
Journal:
Sci Rep
Year:
2016
Document type:
Article
Affiliation country:
France