Cadmium stress induces production of thiol compounds and transcripts for enzymes involved in sulfur assimilation pathways in Arabidopsis

doi:10.1078/0176-1617-00733

Journal of Plant Physiology

Volume 159, Issue 4, 2002, Pages 445-448

https://doi.org/10.1078/0176-1617-00733 Get rights and content

Summary

One of the defense systems against toxic heavy metals in plants is to employ cysteine-rich chelating compounds, phytochelatins, which are polymeric forms of glutathione. In the present study cadmium stressed Arabidopsis was employed in order to investigate the response of genes involved in glutathione biosynthesis via cysteine and production of thiol compounds. The results showed a 13-fold increase in transcripts for ATP sulfurylase, 6 to 10-fold for APS reductase and 2-fold for sulfite reductase, all of which are involved in cysteine synthesis. In addition, a 3-fold increase in total thiols was noted, mainly of glutathione, phytochelatins and cysteine. It is suggested that, to cope with toxic heavy metals, plants activate the sulfur assimilation pathway by increasing transcription of related genes to provide an enhanced supply of glutathione for phytochelatin biosynthesis.

References (21)

C.S. Cobbett
Curr Opin Plant Biol
(2000)
J.R. Domínguez–Solís et al.
J Biol Chem
(2001)
E. Harada et al.
J Plant Physiol
(2000)
E. Harada et al.
J Plant Physiol
(2001)
S. Lee et al.
Plant Sci
(1999)
M. Noji et al.
J Biol Chem
(1998)
L. Sanità di Toppi et al.
Environ Exp Bot
(1999)
C. Barroso et al.
Plant Mol Biol
(1999)
M. Denis et al.
Plant Breeding
(1996)
U. Galli et al.
Planta
(1996)

There are more references available in the full text version of this article.

Cited by (101)

An insight into plant heavy metal/metalloid tolerance and detoxification mechanisms: A critical review
2022, Metals and Metalloids in Soil-Plant-Water Systems: Phytophysiology and Remediation Techniques
In current times, among various environmental pollutions, the toxicity and pollution by heavy metals/metalloids (HMs), which are causing a reduction in crop productivity have gained major public attention. For antagonizing HM toxicity, HMs tolerant/resistant plants tend to employ complex mechanisms at biochemical, physio-morphological, molecular, cellular, tissue to suborganellar and at gross plant levels to adapt adverse conditions. Thus, scientists worldwide need to collect information and current state of art knowledge on the occurrence, toxicity mechanisms and devise suitable remedies and re-strategize various options for management of this problem. This review summarizes the effect of HMs and various useful strategies adopted by plants for their possible detoxification to ameliorate the toxicity/stress generated by HMs, the potential of metal resilient and nonmetal resilient plants can be increased to withstand the environmental extremes in the industrial areas. Based on various reports, this review also lays particular emphasis on some elicitors, highlighting the prospects and insinuation of phyto- and bioremediation that can be engineered in plants for HM/metalloid removal from their habitats besides obtaining transgenics. Therefore, understanding the mechanisms underlying HMs stress tolerance and devising strategies to cope with the HM stress in plants is very important for the development and sustainable approaches of HM-/metalloid-resistant crops.
Differential partitioning of thiols and glucosinolates between shoot and root in Chinese cabbage upon excess zinc exposure
2020, Journal of Plant Physiology
Zinc (Zn) is one of the important elements of plant growth, however, at elevated level it is toxic. Exposure of Chinese cabbage to elevated Zn²⁺ concentrations (5 and 10 μM ZnCl₂) resulted in enhancement of total sulfur and organic sulfur concentration. Transcript level of APS reductase (APR) as a key enzyme in biosynthesis of primary sulfur compounds (cysteine and thiols), was up-regulated in both shoot and root upon exposure to elevated Zn²⁺, which was accompanied by an increase in the concentration of cysteine in both tissues. In contrast, the concentration of thiols increased only in the root by 5.5 and 15-fold at 5 and 10 μM Zn²⁺, respectively, which was in accompanied by an upregulation of ATP sulfurylase, an enzyme responsible for activation of sulfate. An elevated content of glucosinolates, mostly indolic glucosinolates, only in the shoot of plants exposed to excess level of Zn²⁺ coincided with an increase in gene expression of key biosynthetic enzymes and regulators (CYP79B3, CYP83B1, MYB34). Thus distinct acuumulation patterns of sulfur containing compounds in root and shoot of Chinese cabbage may be a strategy for Chinese cabbage to combat with exposure to excess Zn.
Effects of grafting on root-to-shoot cadmium translocation in plants of eggplant (Solanum melongena) and tomato (Solanum lycopersicum)
2019, Science of the Total Environment
Citation Excerpt :
However, emerging studies have also shown that PCs and GSH may be the ‘transporters’ responsible for long-distance Cd translocation from roots to shoots (Chen et al., 2006; Gong et al., 2003; Mendoza-Cózatl et al., 2008), making the role of sulfur more unclear. To date, most studies have focused on the response mechanism of sulfur assimilation in regards to Cd stress (Anjum et al., 2008; Harada et al., 2002; Pereira et al., 2002; Zhou et al., 2014), the current study will add to this growing body of literature by also evaluating how sulfur may be effected by grafting. Eggplant (Solanum melongena) and tomato (Solanum lycopersicum) are different genera within the same family (Solanaceae).
Heavy metal cadmium (Cd) pollution in farmland has become a serious threat to food security globally. In this work, a grafting technique was applied to eggplant (Solanum melongena) and tomato (Solanum lycopersicum) plants using Solanum torvum as rootstock to investigate effects of grafting on Cd accumulation in shoots. The un-grafted, self-grafted, and grafted plants were grown in soils containing 2 mg kg⁻¹ Cd. Results showed that grafting on S. torvum could efficiently reduce Cd accumulation in leaves of eggplant and tomato, and the decrease was 89% and 72%, respectively. With S. torvum as rootstock, Cd concentrations were 1.11 mg kg⁻¹ and 6.58 mg kg⁻¹ in leaves of grafted eggplant and tomato, which were significantly decreased as compared with un-grafted plants (10.12 mg kg⁻¹ and 23.19 mg kg⁻¹, respectively, p < 0.05). In addition, Cd concentrations were 12.11 mg kg⁻¹ and 29.47 mg kg⁻¹ in leaves of self-grafted eggplant and tomato, respectively, which was similar to those in un-grafted eggplant, but more than those in un-grafted tomato (p < 0.05). This suggests that the S. torvum rootstock, and not the grafting operation, was responsible for efficient reduction of Cd accumulation in shoots of eggplant and tomato plants. Furthermore, total sulfur and sulfate (SO₄²⁻) concentrations analysis revealed that there was a similar trend between Cd accumulation and total sulfur or SO₄²⁻ concentrations in leaves of plants tested. Additionally, a strong positive correlation between Cd accumulation and total sulfur or SO₄²⁻ concentrations occurred in leaves of eggplant and tomato plants. Thus, sulfur, mainly SO₄²⁻, in leaves may play an important regulatory role in Cd accumulation of eggplant and tomato plants. This study provides the theoretical and technical support for applying grafting technique for the safe practice of farming in Cd-contaminated agricultural soil.
Role of sulfur metabolism in cadmium tolerance
2019, Cadmium Tolerance in Plants: Agronomic, Molecular, Signaling, and Omic Approaches
Heavy metal–contaminated soils pose a major environmental challenge. Plants uptake various nutrients and solutes from soil for their proper growth and development. The inadvertent uptake of toxic metals can affect plant metabolism, cell structure, transport, and membranes. Cadmium (Cd) is one of the most deleterious soil pollutants and is widely spread in the environment. Cd is phytotoxic, causing plant growth inhibition, stunting, and chlorosis due to altered plant metabolism. Sulfur (S) is an indispensable nutrient for plant growth and physiological functioning. S has a significant role in resistance against various biotic and abiotic stresses. Cd induces oxidative stress that affects the regulation of the S uptake and assimilation process at biochemical and genetic levels. S is incorporated in bioorganic compounds as reduced S in the form of organic sulfide or thiol, which provides protection against heavy metal stress through the synthesis of glucosinolates, allyl sulfur compounds, specialized peptides such as glutathione and phytochelatins, etc. This chapter provides information on the regulation of S metabolism and resistance mechanisms during Cd phytotoxicity.
Sulfate improves cadmium tolerance by limiting cadmium accumulation, modulation of sulfur metabolism and antioxidant defense system in maize
2018, Environmental and Experimental Botany
Citation Excerpt :
Extensive reports are available on Cd induced up-regulation of enzymes involved in sulfur assimilation pathway (Schäfer et al., 1998; Lee and Leustek, 1999; Herbette et al., 2006). Nutritional studies and reverse genetics approaches have also shown the importance of sulfur assimilation pathway in Cd stress alleviation in Arabidopsis thaliana (Dominguez-Solís et al., 2001; Harada et al., 2002), Brassica juncea (Zhu et al., 1999a,b; Bashir et al., 2015), Brassica campestris (Anjum et al., 2008), Nicotiana tabacum (Harada et al., 2001) and Triticum aestivum (Khan et al., 2007; Gaafar et al., 2012). Over the past decade, much emphasis has been given to the possibility of using soil amendments to alleviate Cd toxicity and limits its phytoavailability.
Cadmium (Cd) contamination of agricultural soil has become a serious threat to global food security. The present study highlights the role of added sulfate (SO₄²⁻) in modulating sulfur metabolism and antioxidant defense system conferring tolerance against Cd stress in maize. Expression patterns of antioxidant genes, transporters involved in SO₄²⁻ and Cd accumulation, antioxidant enzyme activity, membrane damage, in vivo reactive oxygen species (ROS) detection and hydrogen peroxide (H₂O₂) accumulation under Cd stress in presence (T₂) or absence (T₁) of excess SO₄²⁻ were studied to get an overview of cellular manoeuvering in conquering Cd induced oxidative stress damages. Moreover, dynamic correlations between miR398a, miR395d, miR408a and their target genes under Cd exposure were validated through qRT-PCR. Supplementation of the ¼ Murashige and Skoog (MS) media with excess sulfate [600 μM (NH₄)₂SO₄] markedly restored the shoot biomass under Cd stress (100 μM CdCl₂). Presence of excess SO₄²⁻ in the nutrient media significantly reduced Cd uptake as well as tissue Cd accumulation in T₂ plants. Foliar dark blue and deep brown spots revealed after histochemical staining with nitroblue tetrazolium (NBT) and 3′3′-diaminobenzidine (DAB) respectively indicated severe oxidative burst in T₁ plants under Cd treatment. The chloromethyl derivative of 2′, 7′-Dichlorofluorescin diacetate (CM-H2DCFDA) and dihydroethidium (DHE) staining further supported enhanced ROS formation in roots of Cd challenged T₁ plants. Enhanced reduced glutathione (GSH) level both in root and above ground part of T₂ plants might be responsible for their better performance under Cd stressed condition as evident from non-significant increase in superoxide anion (O₂⁻), low H₂O₂ and thiobarbituric acid reactive substances (TBARS) levels as compared to T₁ plants. Taken together, our findings indicate that fine adaptation of sulfate uptake and assimilation in sulfate supplemented maize plants (T₂) might satisfy two contrasting needs: (a) maintaining high GSH pool essential for sustaining balanced redox status under stress condition; (b) alleviating Cd stress effects by means of GSH mediated detoxification pathways.
A Comparative Study of Growth Performance, Blood Biochemistry, Rumen Fermentation, and Ruminal and Fecal Bacterial Structure between Yaks and Cattle Raised under High Concentrate Feeding Conditions
2023, Microorganisms

View all citing articles on Scopus

View full text

Cadmium stress induces production of thiol compounds and transcripts for enzymes involved in sulfur assimilation pathways in Arabidopsis

Summary

Curr Opin Plant Biol

J Biol Chem

J Plant Physiol

J Plant Physiol

Plant Sci

J Biol Chem

Environ Exp Bot

Plant Mol Biol

Plant Breeding

Planta