Document Server@UHasselt >
Research >
Research publications >

Please use this identifier to cite or link to this item: http://hdl.handle.net/1942/18493

Title: MiRNA398b and miRNA398c are involved in the regulation of the SOD response in uranium-exposed Arabidopsis thaliana roots
Authors: SAENEN, Eline
VANHOUDT, Nathalie
Vandenhove, H.
Van Hees, M.
Wannijn, J.
Issue Date: 2015
Abstract: The chemical speciation of uranium (U), and hence its toxicity, is strongly dependent on pH. However, oxidative stress responses after U exposure have mainly been investigated in Arabidopsis thaliana plants at pH 5.5, the ideal pH for growing plants in a hydroponic setup. As the pH of pore water can vary strongly, the aim of this study is to investigate oxidative stress responses induced in roots of A. thaliana plants exposed to different U concentrations at pH 4.5 and hence at a high free uraynl (UO2 2+) concentration. In addition to analyzing growth reduction, effects were analysed at enzyme, metabolite and genetic level. Results indicate that U is highly toxic at low pH resulting in a significant decrease in fresh weight (EC50 value for root growth reduction: 28.14 1.59mM U). In addition, no intact RNA could be extracted from the roots exposed to 75 and 100mM U and the ascorbate concentrations could not be determined in roots exposed to 50, 75 or 100mM U indicating that the roots are seriously damaged. Concerning the antioxidative defence system, the involvement of miRNA398b/c in the regulation of the superoxide dismutase (SOD) response was observed after U exposure. As such, a significant increase in MIR398b/c expression was observed, accompanied by a decreased copper/zinc SOD (CSD1/2) expression. The latter was compensated by an increased expression of iron SOD (FSD1) to maintain the SOD capacity in the plastids. While the involvement of miRNA398b/c was already reported before under copper or cadmium stress, this is the first time that it is reported for U.
Notes: Corresponding author at: Belgian Nuclear Research Centre (SCK CEN), Biosphere Impact Studies, Boeretang 200, 2400 Mol, Belgium. Tel.: +32 14 33 88 11. eline.saenen@sckcen.be (E. Saenen).
URI: http://hdl.handle.net/1942/18493
DOI: 10.1016/j.envexpbot.2015.03.003
ISI #: 000354584800002
ISSN: 0098-8472
Category: A1
Type: Journal Contribution
Validation: ecoom, 2016
Appears in Collections: Research publications

Files in This Item:

Description SizeFormat
published version1.15 MBAdobe PDF

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.