Overexpression of AtHMA4 enhances root-to-shoot translocation of zinc and cadmium and plant metal tolerance.
AtHMA4 is an Arabidopsis thaliana P1B-ATPase which transports Zn and Cd. Here, we demonstrate that AtHMA4 is localized at the plasma membrane and expressed in tissues surrounding the root vascular vessels. The ectopic overexpression of AtHMA4 improved the root growth in the presence of toxic concentrations of Zn, Cd and Co. A null mutant exhibited a lower translocation of Zn and Cd from the roots to shoot. In contrast, the AtHMA4 overexpressing lines displayed an increase in the zinc and cadmium shoot content. Altogether, these results strongly indicate that AtHMA4 plays a role in metal loading in the xylem.
Verret
Frédéric
F
CEA Cadarache, DSV/DEVM/Laboratoire des Echanges Membranaires et Signalisation, UMR 6191 CNRS-CEA-Aix-Marseille II, F-13108 St Paul les Durance Cedex, France.
Gravot
Antoine
A
Auroy
Pascaline
P
Leonhardt
Nathalie
N
David
Pascale
P
Nussaume
Laurent
L
Vavasseur
Alain
A
Richaud
Pierre
P
D000251:Adenosine Triphosphatases / Q000235:genetics* / Q000378:metabolism*; D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism*; D001483:Base Sequence; D001692:Biological Transport; D003001:Cloning, Molecular; D003300:Copper / Q000378:metabolism*; D017931:DNA Primers; D004361:Drug Tolerance; D005091:Exons / Q000235:genetics; D020869:Gene Expression Profiling; D007438:Introns / Q000235:genetics; D015032:Zinc / Q000378:metabolism*
D029681:Arabidopsis Proteins; D017931:DNA Primers; D003300:Copper; D000251:Adenosine Triphosphatases; C477864:HMA4 protein, Arabidopsis; D015032:Zinc