Title: Uranium accumulation in Brassica juncea plant facilitated by calcium in carbonate water

Accession Number: doi:10.6073/pasta/de126e8a81a2158c25cb169ac4afb87c

Link to Dataset: https://doi.org/10.6073/pasta/de126e8a81a2158c25cb169ac4afb87c

Repository: EDI Data Portal (Environmental Data Initiative)

Data Type(s): Chemical & Chemical Biology, Imaging Data

Organism(s): Brassica juncea

Summary: he role of calcium (Ca) on the cellular distribution of U(VI) in Brassica juncea roots and root-to-shoot translocation was investigated using hydroponic experiments, microscopy, and spectroscopy. Uranium accumulated mainly in the roots (727 9376 mg kg 1) after 30 days of exposure to 80 M dissolved U in water containing 1 mM HCO3 at different Ca concentrations (0 6 mM) at pH 7.5. However, the concentration of U in the shoots increased 22 times in experiments with 6 mM Ca compared to 0 mM Ca. In the Ca control experiment, transmission electron microscopy energy-dispersive spectroscopy analyses detected U P-bearing precipitates in the cortical apoplast of parenchyma cells. In experiments with 0.3 mM Ca, U P-bearing precipitates were detected in the cortical apoplast and the bordered pits of xylem cells. In experiments with 6 mM Ca, U P-bearing precipitates aggregated in the xylem with no apoplastic precipitation. These results indicate that Ca in carbonate water inhibits the transport and precipitation of U in the root cortical apoplast and facilitates the symplastic transport and translocation toward shoots. These findings reveal the considerable role of Ca in the presence of carbonate in facilitating the transport of U in plants and present new insights for future assessment and phytoremediation strategies.