Bypassing Iron Storage in Endodermal Vacuoles Rescues the Iron Mobilization Defect in the <i>natural resistance associated-macrophage protein3natural resistance associated-macrophage protein4</i> Double Mutant

Mary, Viviane; Ramos, Magali Schnell; Gillet, Cynthia; Socha, Amanda; Giraudat, Jérôme; Agorio, Astrid; Merlot, Sylvain; Clairet, Colin; Kim, Sun A.; Punshon, Tracy; Guerinot, Mary Lou; Thomine, Sébastien

doi:10.1104/pp.15.00380

Cited by 56 publications

(70 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In agreement with published data, nramp3‐1 nramp4‐1 plants developed severe chlorosis under iron limitation (Figure H, −Fe; ABIS medium with 50 μM ferrozine), but greened normally when grown on medium supplemented with iron (Figure H, +Fe; ABIS medium supplemented with 50 μM FeHBED). Accordingly, chlorophyll concentrations of nramp3‐1 nramp4‐1 were significantly lower than those of WT, when seedlings were grown without external iron‐supply (Figure S1 and Table S1 in Appendix S1, Supporting Information).…”

Section: Resultssupporting

confidence: 91%

“…As a control, we included nramp4‐1 single k.o., and nramp3‐1 nramp4‐1 double k.o. plants, for which characteristic iron‐dependent phenotypes have been described earlier . In WT plants, NRAMP3 and NRAMP4 localize to the TP, releasing divalent cations (including iron) to the cytosol .…”

Section: Resultsmentioning

confidence: 77%

“…Because early seedling development requires remobilization of iron from the vacuole, a k.o. of both transporters results in chlorosis in young plants if iron is limited, and cannot be taken up from the growth medium …”

Section: Resultsmentioning

confidence: 99%

“…For the measurement of primary root lengths and analysis of etiolated seedlings, plants were cultivated on vertically placed 1/2 strength MS plates with 2% sucrose. Growth on Fe‐sufficient and Fe‐deficient medium and measurement of chlorophyll content was performed with seedlings grown on horizontally placed plates on ABIS medium with 50 μM FeHBED (+Fe), or without Fe and an additional 50 μM ferrozine [3‐(2‐pyridyl)‐5,6‐bis(4‐phenyl‐sulfonic acid)‐1,2,4‐triazine] (‐Fe) as described previously …”

Section: Methodsmentioning

confidence: 99%

See 3 more Smart Citations

Sorting of Arabidopsis NRAMP3 and NRAMP4 depends on adaptor protein complex AP4 and a dileucine‐based motif

Müdsam

Wollschläger

Sauer

et al. 2018

Traffic

View full text Add to dashboard Cite

Adaptor protein complexes mediate cargo selection and vesicle trafficking to different cellular membranes in all eukaryotic cells. Information on the role of AP4 in plants is still limited. Here, we present the analyses of Arabidopsis thaliana mutants lacking different subunits of AP4. These mutants show abnormalities in their development and in protein sorting. We found that growth of roots and etiolated hypocotyls, as well as male fertility and trichome morphology are disturbed in ap4. Analyses of GFP-fusions transiently expressed in mesophyll protoplasts demonstrated that the tonoplast (TP) proteins MOT2, NRAMP3 and NRAMP4, but not INT1, are partially sorted to the plasma membrane (PM) in the absence of a functional AP4 complex. Moreover, alanine mutagenesis revealed that in wild-type plants, sorting of NRAMP3 and NRAMP4 to the TP requires an N-terminal dileucine-based motif. The NRAMP3 or NRAMP4 N-terminal domain containing the dileucine motif was sufficient to redirect the PM localized INT4 protein to the TP and to confer AP4-dependency on sorting of INT1. Our data show that correct sorting of NRAMP3 and NRAMP4 depends on both, an N-terminal dileucine-based motif as well as AP4.

show abstract

Section: Resultssupporting

confidence: 91%

Section: Resultsmentioning

confidence: 77%

Section: Resultsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

See 2 more Smart Citations

Sorting of Arabidopsis NRAMP3 and NRAMP4 depends on adaptor protein complex AP4 and a dileucine‐based motif

Müdsam

Wollschläger

Sauer

et al. 2018

Traffic

View full text Add to dashboard Cite

show abstract

“…One of the suppressors was mutated in the vacuolar influx transporter VACUOLAR IRON TRANSPORTER 1 (VIT1), resulting in the reallocation of Fe in cells of the cortex that do not depend on NRAMP3 and NRAMP4 for Fe remobilization. Although not strictly bypassing the vacuolar storage, this candidate mutation demonstrated the plasticity of seeds to store Fe in different cell types and compartments (Mary et al ., ).…”

Section: Fe In the Seed: Acquisition And Distribution Strategiesmentioning

confidence: 97%

New routes for plant iron mining

Curie

Mari

2016

New Phytologist

View full text Add to dashboard Cite

Contents 521I.521II.522III.523IV.524525References525 Summary Plant iron (Fe) uptake relies to a large extent on the capacity of cells to control and extract Fe pools safely conserved in extracytoplasmic environments such as the apoplast and vacuoles, at least as much as on the transport machinery nested in plasma membranes. Recent studies on root and embryo Fe nutrition support this assertion and show that the root Fe‐deficiency response also includes the dynamic use of a large Fe reservoir bound to cell wall components in the root apoplast, secretion in the apoplast of phenolic compounds of the coumarin family, which solubilize Fe in calcareous soils, and inhibition of suberization of endodermal cells in order to allow apoplastic and transcellular radial transport of Fe. All of these responses are regulated by the stress hormones ethylene and abscisic acid (ABA), suggesting an integrated strategy within the root to adapt to Fe shortage. For its nutrition, the embryo has developed both an original uptake mechanism, in which ascorbate is effluxed to chemically reduce Fe3+ to the transport‐competent Fe2+ form, and an efficient strategy to control utilization of a large Fe pool in vacuoles. This review will attempt to summarize exciting new insights into the diverse routes that Fe takes to feed plant tissues.

show abstract