Involved in the phloem transport of iron and manganese and their translocation into the grain. Transports iron- and manganese-nicotianamine chelates, but not iron-phytosiderophore. Expressed in phloem cells of vascular bundles in leaves and leaf sheaths. Expressed at low levels in phloem companion cells in the central cylinder of roots, but not in the epidermal or cortical cells. Before anthesis, expressed in the vascular bundles of spikelets and at low levels in the central region of anthers. After fertilization, expression in bundles increases especially in the upper part of the husk. At 5 days after anthesis, highly expressed in the developing ovary and 3 days later in the developing embryo and outer layer of the endosperm. From 20 to 30 days after anthesis, expressed in mature embryo and peripheral layer of the endosperm. In leaves by iron deficiency. Belongs to the YSL (TC 2.A.67.2) family.