Format

Send to

Choose Destination
Plant Physiol. 2016 Feb;170(2):1014-29. doi: 10.1104/pp.15.01163. Epub 2015 Dec 11.

Identification of a Stelar-Localized Transport Protein That Facilitates Root-to-Shoot Transfer of Chloride in Arabidopsis.

Author information

1
Australian Centre for Plant Functional Genomics (B.L., J.Q., U.B., M.H., A.E., D.J., M.T., S.J.R.), School of Agriculture, Food, and Wine (B.L., C.B., J.Q., U.B., M.H., A.E., G.M.M., D.J., S.W.H., M.T., M.G., S.J.R.), and ARC Centre of Excellence in Plant Energy Biology (C.B., J.Q., S.W.H., M.G.), University of Adelaide, SA 5064, Australia;Centre for Desert Agriculture, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia (B.L., M.T.);School of BioSciences, University of Melbourne, Parkville, Vic 3010, Australia (A.A.T.J.); and Centre for Genomics and Systems Biology, New York University, New York 10003 (K.D.B.).
2
Australian Centre for Plant Functional Genomics (B.L., J.Q., U.B., M.H., A.E., D.J., M.T., S.J.R.), School of Agriculture, Food, and Wine (B.L., C.B., J.Q., U.B., M.H., A.E., G.M.M., D.J., S.W.H., M.T., M.G., S.J.R.), and ARC Centre of Excellence in Plant Energy Biology (C.B., J.Q., S.W.H., M.G.), University of Adelaide, SA 5064, Australia;Centre for Desert Agriculture, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia (B.L., M.T.);School of BioSciences, University of Melbourne, Parkville, Vic 3010, Australia (A.A.T.J.); and Centre for Genomics and Systems Biology, New York University, New York 10003 (K.D.B.) mark.tester@kaust.edu.sa matthew.gilliham@adelaide.edu.au.

Abstract

Under saline conditions, higher plants restrict the accumulation of chloride ions (Cl(-)) in the shoot by regulating their transfer from the root symplast into the xylem-associated apoplast. To identify molecular mechanisms underpinning this phenomenon, we undertook a transcriptional screen of salt stressed Arabidopsis (Arabidopsis thaliana) roots. Microarrays, quantitative RT-PCR, and promoter-GUS fusions identified a candidate gene involved in Cl(-) xylem loading from the Nitrate transporter 1/Peptide Transporter family (NPF2.4). This gene was highly expressed in the root stele compared to the cortex, and its expression decreased after exposure to NaCl or abscisic acid. NPF2.4 fused to fluorescent proteins, expressed either transiently or stably, was targeted to the plasma membrane. Electrophysiological analysis of NPF2.4 in Xenopus laevis oocytes suggested that NPF2.4 catalyzed passive Cl(-) efflux out of cells and was much less permeable to NO3(-). Shoot Cl(-) accumulation was decreased following NPF2.4 artificial microRNA knockdown, whereas it was increased by overexpression of NPF2.4. Taken together, these results suggest that NPF2.4 is involved in long-distance transport of Cl(-) in plants, playing a role in the loading and the regulation of Cl(-) loading into the xylem of Arabidopsis roots during salinity stress.

PMID:
26662602
PMCID:
PMC4734554
DOI:
10.1104/pp.15.01163
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center