Fig. 2: LPR2 is a cell wall ferroxidase and is irreplaceable by LPR1.
From: Phloem iron remodels root development in response to ammonium as the major nitrogen source
a Fluorescence co-localization of LPR2-GFP and propidium iodide in cells of p35S::LPR2-GFP roots. b Fluorescence of LPR2-GFP and FM4-64 in cells of p35S::LPR2-GFP roots after plasmolysis with 0.8 M sorbitol. Four-day-old seedlings were transferred to NH4+ medium with 100 µM Fe, and confocal analyses were performed 4 days after seedling transfer. c Ferroxidase activities of recombinant GST-LPR2. Ferroxidase assay using 1 μg purified GST-LPR2 protein. Pink indicates the Fe2+-ferrozine complex. The substrate Fe2+ was added in the form of Fe(NH4)2(SO4)2·6H2O at an initial concentration of 50 μM. d Fe2+ concentration-dependent (0–300 μM) ferroxidase activity of GST-LPR2 protein. Data shown are mean ± SD of three biological replicates. e, f Phenotype of lpr2-1 mutant lines with LPR2 promoter-confined tissue-specific expression of LPR1CDS and LPR1genomic. Four-day-old seedlings of the indicated genotypes were transferred to NO3− or NH4+ medium with 100 µM Fe and analyzed 4 days after seedling transfer. Two (c, d) or three (a, b, e, f) independent experiments were performed with similar results, and one representative experiment is shown.
