Knocking Out ACR2 Does Not Affect Arsenic Redox Status in Arabidopsis thaliana: Implications for As Detoxification and Accumulation in Plants
- Rothamsted Research (United Kingdom); Hebei Agricultural University (China)
- Vrije Univ., Amsterdam (Netherlands)
- Rothamsted Research (United Kingdom)
- Univ. of Saskatchewan, Saskatoon, SK (Canada)
- Univ. of Aberdeen (United Kingdom)
- Nanjing Agricultural University (China)
Many plant species are able to reduce arsenate to arsenite efficiently, which is an important step allowing detoxification of As through either efflux of arsenite or complexation with thiol compounds. It has been suggested that this reduction is catalyzed by ACR2, a plant homologue of the yeast arsenate reductase ScACR2. Silencing of AtACR2 was reported to result in As hyperaccumulation in the shoots of Arabidopsis thaliana. However, no information of the in vivo As speciation has been reported. Here, we investigated the effect of AtACR2 knockout or overexpression on As speciation, arsenite efflux from roots and As accumulation in shoots. T-DNA insertion lines, overexpression lines and wild-type (WT) plants were exposed to different concentrations of arsenate for different periods, and As speciation in plants and arsenite efflux were determined using HPLC-ICP-MS. There were no significant differences in As speciation between different lines, with arsenite accounting for >90% of the total extractable As in both roots and shoots. Arsenite efflux to the external medium represented on average 77% of the arsenate taken up during 6 h exposure, but there were no significant differences between WT and mutants or overexpression lines. Accumulation of As in the shoots was also unaffected by AtACR2 knockout or overexpression. Additionally, after exposure to arsenate, the yeast (Saccharomyces cerevisiae) strain with ScACR2 deleted showed similar As speciation as the WT with arsenite-thiol complexes being the predominant species. Our results suggest the existence of multiple pathways of arsenate reduction in plants and yeast.
- Research Organization:
- SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States). Stanford Synchrotron Radiation Lightsource (SSRL)
- Sponsoring Organization:
- USDOE Office of Science (SC), Biological and Environmental Research (BER); National Science Foundation (NSF); National Institutes of Health (NIH)
- Grant/Contract Number:
- AC02-76SF00515; IOS 0844413; P41RR001209
- OSTI ID:
- 1903994
- Journal Information:
- PLoS ONE, Vol. 7, Issue 8; ISSN 1932-6203
- Publisher:
- Public Library of ScienceCopyright Statement
- Country of Publication:
- United States
- Language:
- English
The role of nodes in arsenic storage and distribution in rice
|
journal | April 2015 |
Genome-wide Association Mapping Identifies a New Arsenate Reductase Enzyme Critical for Limiting Arsenic Accumulation in Plants
|
journal | December 2014 |
Arsenic Hyperaccumulation Strategies: An Overview
|
journal | July 2017 |
Arsenic Transport in Rice and Biological Solutions to Reduce Arsenic Risk from Rice
|
journal | March 2017 |
Similar Records
Arsenic speciation in tissues of the hyperacumulator P. calomelanos var. austroamericana using x-ray absorption spectroscopy.
Arsenic Detoxification by Geobacter Species