A specific transporter for iron(III)-phytosiderophore in barley roots

Yoshiko Murata, Jian Feng Ma, Naoki Yamaji, Daisei Ueno, Kyosuke Nomoto, Takashi Iwashita

    Research output: Contribution to journalArticlepeer-review

    191 Citations (Scopus)

    Abstract

    Iron acquisition of graminaceous plants is characterized by the synthesis and secretion of the iron-chelating phytosiderophore, mugineic acid (MA), and by a specific uptake system for iron(III)-phytosiderophore complexes. We identified a gene specifically encoding an iron-phytosiderophore transporter (HvYS1) in barley, which is the most tolerant species to iron deficiency among graminaceous plants. HvYS1 was predicted to encode a polypeptide of 678 amino acids and to have 72.7% identity with ZmYS1, a first protein identified as an iron(III)-phytosiderophore transporter in maize. Real-time RT-PCR analysis showed that the HvYS1 gene was mainly expressed in the roots, and its expression was enhanced under iron deficiency. In situ hybridization analysis of iron-deficient barley roots revealed that the mRNA of HvYS1 was localized in epidermal root cells. Furthermore, immunohistological staining with anti-HvYS1 polyclonal antibody showed the same localization as the mRNA. HvYS1 functionally complemented yeast strains defective in iron uptake on media containing iron(III)-MA, but not iron-nicotianamine (NA). Expression of HvYS1 in Xenopus oocytes showed strict specificity for both metals and ligands: HvYS1 transports only iron(III) chelated with phytosiderophore. The localization and substrate specificity of HvYS1 is different from those of ZmYS1, indicating that HvYS1 is a specific transporter for iron(III)-phytosiderophore involved in primary iron acquisition from soil in barley roots.

    Original languageEnglish
    Pages (from-to)563-572
    Number of pages10
    JournalPlant Journal
    Volume46
    Issue number4
    DOIs
    Publication statusPublished - May 2006

    Keywords

    • Epidermal cells of barley roots
    • Iron(III)-phytosiderophore transporter
    • Mugineic acid
    • Nicotianamine
    • Tolerance of iron deficiency
    • YS1 gene

    ASJC Scopus subject areas

    • Genetics
    • Plant Science
    • Cell Biology

    Fingerprint

    Dive into the research topics of 'A specific transporter for iron(III)-phytosiderophore in barley roots'. Together they form a unique fingerprint.

    Cite this