title: Arabidopsis IRT3 is a zinc-regulated and plasma membrane localized zinc/iron transporter.
abstract: ZIP transporters (ZRT, IRT-like proteins) are involved in the transport of iron (Fe), zinc (Zn) and other divalent metal cations. The expression of IRT3, a ZIP transporter, is higher in the Zn/cadmium (Cd) hyperaccumulator Arabidopsis halleri than is that of its ortholog in Arabidopsis thaliana, which implies a positive association of its expression with Zn accumulation in A. halleri. IRT3 genes from both A. halleri and A. thaliana functionally complemented the Zn uptake mutant Spzrt1 in Schizosaccharomyces pombe; and Zn uptake double mutant zrt1zrt2, Fe-uptake mutant fet3fet4 and conferred Zn and Fe uptake activity in Saccharomyces cerevisiae. By contrast, the manganese (Mn) uptake mutant smf1 phenotypes were not rescued. Insufficient Cd uptake for toxicity was found. Expression of IRT3-green fluorescent protein (GFP) fusion proteins in Arabidopsis root protoplasts indicated localization of both IRT3 proteins in the plasma membrane. Overexpressing AtIRT3 in A. thaliana led to increased accumulation of Zn in the shoot and Fe in the root of transgenic lines. Therefore, IRT3 functions as a Zn and Fe-uptake transporter in Arabidopsis.
authors.affiliation: Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan, Republic of China.
authors.forename: Ya-Fen
authors.initials: YF
authors.lastname: Lin
authors.affiliation: Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan, Republic of China.
authors.forename: Hong-Ming
authors.initials: HM
authors.lastname: Liang
authors.affiliation: Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan, Republic of China.
authors.forename: Shu-Yi
authors.initials: SY
authors.lastname: Yang
authors.affiliation: Leibniz-Institut für Pflanzenbiochemie, Halle, Germany.
authors.forename: Annegret
authors.initials: A
authors.lastname: Boch
authors.affiliation: Leibniz-Institut für Pflanzenbiochemie, Halle, Germany.|Department of Plant Physiology, University of Bayreuth, Bayreuth, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Clemens
authors.affiliation: Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan, Republic of China.
authors.forename: Chyi-Chuann
authors.initials: CC
authors.lastname: Chen
authors.affiliation: Institute of Plant and Microbial Biology, Academia Sinica, Taiwan, Republic of China.
authors.forename: Jing-Fen
authors.initials: JF
authors.lastname: Wu
authors.affiliation: Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan, Republic of China.
authors.forename: Jing-Ling
authors.initials: JL
authors.lastname: Huang
authors.affiliation: Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan, Republic of China.
authors.forename: Kuo-Chen
authors.initials: KC
authors.lastname: Yeh
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D001692:Biological Transport / Q000235:genetics; D002104:Cadmium / Q000378:metabolism; D027682:Cation Transport Proteins / Q000235:genetics* / Q000378:metabolism; D002462:Cell Membrane / Q000235:genetics; D015870:Gene Expression; D017343:Genes, Plant; D007501:Iron / Q000378:metabolism*; D008345:Manganese / Q000378:metabolism; D026901:Membrane Transport Proteins / Q000235:genetics*; D015032:Zinc / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D027682:Cation Transport Proteins; C542090:IRT3 protein, Arabidopsis; D026901:Membrane Transport Proteins; D002104:Cadmium; D008345:Manganese; D007501:Iron; D015032:Zinc