Advanced

Effects of Ca addition on the uptake, translocation, and distribution of Cd in Arabidopsis thaliana

Zeng, Lihua; Zhu, Ting; Gao, Ya; Wang, Yutao; Ning, Chanjuan; Björn, Lars Olof LU ; Chen, Da and Li, Shaoshan (2017) In Ecotoxicology and Environmental Safety 139. p.228-237
Abstract

Cadmium (Cd) pollution poses a risk to human health for its accumulation in soil and crops, but this can be alleviated by calcium (Ca) addition. However, its mechanism remains unclear yet. In this study, Arabidopsis thaliana was used to explore the alleviating effects of Ca on Cd toxicity and its specific function during uptake, upward-translocation, and distribution of Cd. Supplementing plants with 5 mM CaCl2 alleviated the intoxication symptoms caused by 50 μM CdCl2, such as smaller leaves, early bolting and root browning. Ca addition decreased uptake of Cd, possibly by reducing the physical adsorption of Cd since the root cell membrane was well maintained and lignin deposition was decreased as well, and by... (More)

Cadmium (Cd) pollution poses a risk to human health for its accumulation in soil and crops, but this can be alleviated by calcium (Ca) addition. However, its mechanism remains unclear yet. In this study, Arabidopsis thaliana was used to explore the alleviating effects of Ca on Cd toxicity and its specific function during uptake, upward-translocation, and distribution of Cd. Supplementing plants with 5 mM CaCl2 alleviated the intoxication symptoms caused by 50 μM CdCl2, such as smaller leaves, early bolting and root browning. Ca addition decreased uptake of Cd, possibly by reducing the physical adsorption of Cd since the root cell membrane was well maintained and lignin deposition was decreased as well, and by decreasing symplastic Cd transport. Expression of the genes involved (AtZIP2 and AtZIP4) was also decreased. In addition, Ca accumulated in the plant shoot to help facilitating the upward-translocation of Cd, with evidence of higher translocation factor and expression of genes that were involved in Ca transport (AtPCR1) and Cd xylem loading (AtHMA2 and AtHMA4). Dithizone-staining of Cd in leaves showed that in Cd+Ca-treated plants, Ca addition initially protected the leaf stomata by preventing Cd from entering guard cells, but with prolonged Cd treatment facilitated the Cd accumulation around trichomes and maybe its excretion. We conclude that Ca promotes the upward-translocation of Cd and changes its distribution in leaves. The results may have relevance for bioremediation.

(Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Alleviating effect, Cd distribution, Cd toxicity, Cd uptake and translocation, Exogenous Ca
in
Ecotoxicology and Environmental Safety
volume
139
pages
10 pages
publisher
Elsevier
external identifiers
  • scopus:85010876647
  • wos:000396640600030
ISSN
0147-6513
DOI
10.1016/j.ecoenv.2017.01.023
language
English
LU publication?
yes
id
becf30a2-fe78-460d-bbb1-697483044028
date added to LUP
2017-02-14 08:35:49
date last changed
2018-01-07 11:49:30
@article{becf30a2-fe78-460d-bbb1-697483044028,
  abstract     = {<p>Cadmium (Cd) pollution poses a risk to human health for its accumulation in soil and crops, but this can be alleviated by calcium (Ca) addition. However, its mechanism remains unclear yet. In this study, Arabidopsis thaliana was used to explore the alleviating effects of Ca on Cd toxicity and its specific function during uptake, upward-translocation, and distribution of Cd. Supplementing plants with 5 mM CaCl<sub>2</sub> alleviated the intoxication symptoms caused by 50 μM CdCl<sub>2</sub>, such as smaller leaves, early bolting and root browning. Ca addition decreased uptake of Cd, possibly by reducing the physical adsorption of Cd since the root cell membrane was well maintained and lignin deposition was decreased as well, and by decreasing symplastic Cd transport. Expression of the genes involved (AtZIP2 and AtZIP4) was also decreased. In addition, Ca accumulated in the plant shoot to help facilitating the upward-translocation of Cd, with evidence of higher translocation factor and expression of genes that were involved in Ca transport (AtPCR1) and Cd xylem loading (AtHMA2 and AtHMA4). Dithizone-staining of Cd in leaves showed that in Cd+Ca-treated plants, Ca addition initially protected the leaf stomata by preventing Cd from entering guard cells, but with prolonged Cd treatment facilitated the Cd accumulation around trichomes and maybe its excretion. We conclude that Ca promotes the upward-translocation of Cd and changes its distribution in leaves. The results may have relevance for bioremediation.</p>},
  author       = {Zeng, Lihua and Zhu, Ting and Gao, Ya and Wang, Yutao and Ning, Chanjuan and Björn, Lars Olof and Chen, Da and Li, Shaoshan},
  issn         = {0147-6513},
  keyword      = {Alleviating effect,Cd distribution,Cd toxicity,Cd uptake and translocation,Exogenous Ca},
  language     = {eng},
  month        = {05},
  pages        = {228--237},
  publisher    = {Elsevier},
  series       = {Ecotoxicology and Environmental Safety},
  title        = {Effects of Ca addition on the uptake, translocation, and distribution of Cd in Arabidopsis thaliana},
  url          = {http://dx.doi.org/10.1016/j.ecoenv.2017.01.023},
  volume       = {139},
  year         = {2017},
}