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Gaddam SR, Sharma A, Trivedi PK. miR397b-LAC2 module regulates cadmium stress response by coordinating root lignification and copper homeostasis in Arabidopsis thaliana. JOURNAL OF HAZARDOUS MATERIALS 2024; 465:133100. [PMID: 38042003 DOI: 10.1016/j.jhazmat.2023.133100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 11/20/2023] [Accepted: 11/24/2023] [Indexed: 12/04/2023]
Abstract
Non-essential heavy metal cadmium (Cd) is toxic to plants and animals. Cadmium affects plant photosynthesis, respiration, and causes water imbalance and may lead to plant death. Cadmium induces toxicity by interfering with the essential metal copper (Cu) homeostasis, which affects plant nutrition. Though root lignin biosynthesis is positively regulated by Cd stress, the underlying mechanisms promoting lignin accumulation and controlling Cd-induced Cu limitation responses are unclear. Here, we elucidated the role of Cu-responsive microRNA (miR397b) in Arabidopsis thaliana plants for Cd stress by targeting the LACCASE2 (LAC2) gene. This study demonstrated the fundamental mechanism of miR397b-mediated Cd stress response by enhancing the lignin content in root tissues. We developed miR397b over-expressing plants, which showed considerable Cd stress tolerance. Plants with knockdown function of LAC2 also showed significant tolerance to Cd stress. miR397b overexpressing and lac2 mutant plants showed root reduction, higher biomass and chlorophyll content, and significantly lower Reactive Oxygen Species (ROS). This study demonstrated the miR397b-mediated Cd stress response in Arabidopsis by enhancing the lignin content in root tissues. We conclude that modulation in miR397b can be potentially used for improving plants for Cd tolerance and Cu homeostasis.
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Affiliation(s)
- Subhash Reddy Gaddam
- CSIR-National Botanical Research Institute, Council of Scientific and Industrial Research (CSIR-NBRI), Rana Pratap Marg, Lucknow 226001, India; CSIR, Central Institute of Medicinal and Aromatic Plants (CSIR-CIMAP), P.O. CIMAP, Near Kukrail Picnic Spot, Lucknow 226 015, India
| | - Ashish Sharma
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India; CSIR, Central Institute of Medicinal and Aromatic Plants (CSIR-CIMAP), P.O. CIMAP, Near Kukrail Picnic Spot, Lucknow 226 015, India
| | - Prabodh Kumar Trivedi
- CSIR-National Botanical Research Institute, Council of Scientific and Industrial Research (CSIR-NBRI), Rana Pratap Marg, Lucknow 226001, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India; CSIR, Central Institute of Medicinal and Aromatic Plants (CSIR-CIMAP), P.O. CIMAP, Near Kukrail Picnic Spot, Lucknow 226 015, India.
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Abdullah, Wani KI, Naeem M, Jha PK, Jha UC, Aftab T, Prasad PVV. Systems biology of chromium-plant interaction: insights from omics approaches. FRONTIERS IN PLANT SCIENCE 2024; 14:1305179. [PMID: 38259926 PMCID: PMC10800501 DOI: 10.3389/fpls.2023.1305179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Accepted: 12/15/2023] [Indexed: 01/24/2024]
Abstract
Plants are frequently subjected to heavy metal (HM) stress that impedes their growth and productivity. One of the most common harmful trace metals and HM discovered is chromium (Cr). Its contamination continues to increase in the environment due to industrial or anthropogenic activities. Chromium is severely toxic to plant growth and development and acts as a human carcinogen that enters the body by inhaling or taking Cr-contaminated food items. Plants uptake Cr via various transporters, such as sulfate and phosphate transporters. In nature, Cr is found in various valence states, commonly Cr (III) and Cr (VI). Cr (VI) is soil's most hazardous and pervasive form. Cr elevates reactive oxygen species (ROS) activity, impeding various physiological and metabolic pathways. Plants have evolved various complex defense mechanisms to prevent or tolerate the toxic effects of Cr. These defense mechanisms include absorbing and accumulating Cr in cell organelles such as vacuoles, immobilizing them by forming complexes with organic chelates, and extracting them by using a variety of transporters and ion channels regulated by various signaling cascades and transcription factors. Several defense-related proteins including, metallothioneins, phytochelatins, and glutathione-S-transferases aid in the sequestration of Cr. Moreover, several genes and transcriptional factors, such as WRKY and AP2/ERF TF genes, play a crucial role in defense against Cr stress. To counter HM-mediated stress stimuli, OMICS approaches, including genomics, proteomics, transcriptomics, and metallomics, have facilitated our understanding to improve Cr stress tolerance in plants. This review discusses the Cr uptake, translocation, and accumulation in plants. Furthermore, it provides a model to unravel the complexities of the Cr-plant interaction utilizing system biology and integrated OMICS approach.
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Affiliation(s)
- Abdullah
- Department of Botany, Aligarh Muslim University, Aligarh, India
| | | | - M. Naeem
- Department of Botany, Aligarh Muslim University, Aligarh, India
| | - Prakash Kumar Jha
- Department of Plant and Soil Sciences, Mississippi State University, Starkville, MS, United States
| | - Uday Chand Jha
- Indian Institute of Pulses Research (IIPR), Indian Council of Agricultural Research (ICAR), Kanpur, India
- Department of Agronomy, Kansas State University, Manhattan, KS, United States
| | - Tariq Aftab
- Department of Botany, Aligarh Muslim University, Aligarh, India
| | - P. V. Vara Prasad
- Department of Agronomy, Kansas State University, Manhattan, KS, United States
- Department of Agronomy; and Feed the Future Innovation Lab for Collaborative Research on Sustainable Intensification, Kansas State University, Manhattan, KS, United States
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Gao Q, Li X, Xiang C, Li R, Xie H, Liu J, Li X, Zhang G, Yang S, Liang Y, Zhai C, Zhao Y. EbbHLH80 Enhances Salt Responses by Up-Regulating Flavonoid Accumulation and Modulating ROS Levels. Int J Mol Sci 2023; 24:11080. [PMID: 37446256 DOI: 10.3390/ijms241311080] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 06/24/2023] [Accepted: 06/27/2023] [Indexed: 07/15/2023] Open
Abstract
bHLH transcription factors are involved in multiple aspects of plant biology, such as the response to abiotic stress. Erigeron breviscapus is a composite plant, and its rich flavonoids have strong preventive and therapeutic effects on cardio cerebral vascular disease. EbbHLH80, a gene from E. breviscapus that positively regulates flavonoid synthesis, was previously characterized. However, it is unclear whether EbbHLH80 increases flavonoid accumulation, which affects salt tolerance. The function of EbbHLH80 in transgenic tobacco seeds was identified by phylogenetic analysis and metabolome-transcriptome analysis. We investigated the role of EbbHLH80 in salt stress response. Our results showed that the expression of EbbHLH80 increased following salt treatment. Integrating the metabolome and transcriptome analysis of EbbHLH80-OE and Yunyan 87 (WT) seeds, we identified several genes and metabolites related to flavonoid biosynthesis and salt stress. Moreover, EbbHLH80-OE plants displayed higher salt tolerance than wild-type plants during seed germination and seedling growth. After salt treatment, transgenic tobacco had significantly lower levels of reactive oxygen species (ROS) than WT, with enhanced levels of antioxidant enzyme expression. Altogether, our results demonstrated that EbbHLH80 might be a positive regulator, promoting salt tolerance by modulating ROS scavenging and increasing stress-responsive genes.
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Affiliation(s)
- Qingqing Gao
- National-Local Joint Engineering Research Center on Gemplasm Innovation & Utilization of Chinese Medicinal Materials in Southwest, The Key Laboratory of Medicinal Plant Biology of Yunnan Province, Yunnan Agricultural University, Kunming 650201, China
- College of Agronomy & Biotechnology, Yunnan Agricultural University, Kunming 650201, China
| | - Xia Li
- National-Local Joint Engineering Research Center on Gemplasm Innovation & Utilization of Chinese Medicinal Materials in Southwest, The Key Laboratory of Medicinal Plant Biology of Yunnan Province, Yunnan Agricultural University, Kunming 650201, China
- College of Agronomy & Biotechnology, Yunnan Agricultural University, Kunming 650201, China
| | - Chunfan Xiang
- National-Local Joint Engineering Research Center on Gemplasm Innovation & Utilization of Chinese Medicinal Materials in Southwest, The Key Laboratory of Medicinal Plant Biology of Yunnan Province, Yunnan Agricultural University, Kunming 650201, China
- College of Agronomy & Biotechnology, Yunnan Agricultural University, Kunming 650201, China
| | - Ruolan Li
- National-Local Joint Engineering Research Center on Gemplasm Innovation & Utilization of Chinese Medicinal Materials in Southwest, The Key Laboratory of Medicinal Plant Biology of Yunnan Province, Yunnan Agricultural University, Kunming 650201, China
| | - Hongchun Xie
- National-Local Joint Engineering Research Center on Gemplasm Innovation & Utilization of Chinese Medicinal Materials in Southwest, The Key Laboratory of Medicinal Plant Biology of Yunnan Province, Yunnan Agricultural University, Kunming 650201, China
| | - Jia Liu
- National-Local Joint Engineering Research Center on Gemplasm Innovation & Utilization of Chinese Medicinal Materials in Southwest, The Key Laboratory of Medicinal Plant Biology of Yunnan Province, Yunnan Agricultural University, Kunming 650201, China
| | - Xiaoning Li
- National-Local Joint Engineering Research Center on Gemplasm Innovation & Utilization of Chinese Medicinal Materials in Southwest, The Key Laboratory of Medicinal Plant Biology of Yunnan Province, Yunnan Agricultural University, Kunming 650201, China
| | - Guanghui Zhang
- National-Local Joint Engineering Research Center on Gemplasm Innovation & Utilization of Chinese Medicinal Materials in Southwest, The Key Laboratory of Medicinal Plant Biology of Yunnan Province, Yunnan Agricultural University, Kunming 650201, China
- College of Agronomy & Biotechnology, Yunnan Agricultural University, Kunming 650201, China
| | - Shengchao Yang
- National-Local Joint Engineering Research Center on Gemplasm Innovation & Utilization of Chinese Medicinal Materials in Southwest, The Key Laboratory of Medicinal Plant Biology of Yunnan Province, Yunnan Agricultural University, Kunming 650201, China
| | - Yanli Liang
- National-Local Joint Engineering Research Center on Gemplasm Innovation & Utilization of Chinese Medicinal Materials in Southwest, The Key Laboratory of Medicinal Plant Biology of Yunnan Province, Yunnan Agricultural University, Kunming 650201, China
- College of Agronomy & Biotechnology, Yunnan Agricultural University, Kunming 650201, China
| | - Chenxi Zhai
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY 14850, USA
| | - Yan Zhao
- National-Local Joint Engineering Research Center on Gemplasm Innovation & Utilization of Chinese Medicinal Materials in Southwest, The Key Laboratory of Medicinal Plant Biology of Yunnan Province, Yunnan Agricultural University, Kunming 650201, China
- College of Agronomy & Biotechnology, Yunnan Agricultural University, Kunming 650201, China
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Liu L, Li S, Guo J, Li N, Jiang M, Li X. Low temperature tolerance is depressed in wild-type and abscisic acid-deficient mutant barley grown in Cd-contaminated soil. JOURNAL OF HAZARDOUS MATERIALS 2022; 430:128489. [PMID: 35739670 DOI: 10.1016/j.jhazmat.2022.128489] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 01/29/2022] [Accepted: 02/12/2022] [Indexed: 06/15/2023]
Abstract
The accumulation of heavy metals in soil, especially cadmium (Cd), may influence the tolerance of crops to other abiotic stress, such as low temperature. In this study, the low temperature tolerance of abscisic acid (ABA)-deficient mutant (Az34) barley and its wild-type (WT) irrigated with Cd solution (1 g L-1) was tested. It was found that Cd aggravated the destruction of chloroplast ultrastructure and disturbed the ion homeostasis under low temperature. The presence of Cd increased the reactive oxygen species (ROS) accumulation, along with the depressed antioxidant enzyme activities, and limited the plant growth. Compared with WT, Az34 plants had lower ROS scavenging ability and decreased maximum quantum efficiency of PS II (Fv/Fm) under Cd and low temperature. In addition, the C-repeat binding factor and cold response (CBF-COR) signaling pathway was negatively affected by Cd treatment under low temperature, which also reduced the low temperature tolerance in barley. Therefore, it was indicated that the Cd reduced the low temperature tolerance in barley, that highlighted the potential risks of depressed low temperature tolerance caused by Cd pollution in barley.
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Affiliation(s)
- Lei Liu
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Science, Changchun 130102, China
| | - Shuxin Li
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Science, Changchun 130102, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Junhong Guo
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Science, Changchun 130102, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Na Li
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Science, Changchun 130102, China
| | - Miao Jiang
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Science, Changchun 130102, China
| | - Xiangnan Li
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Science, Changchun 130102, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing 100049, China; CAS Engineering Laboratory for Eco-agriculture in Water Source of Liaoheyuan, Chinese Academy of Science, Changchun 130102, China.
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5
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Banerjee A, Roychoudhury A. Dissecting the phytohormonal, genomic and proteomic regulation of micronutrient deficiency during abiotic stresses in plants. Biologia (Bratisl) 2022. [DOI: 10.1007/s11756-022-01099-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Amaral Dos Reis R, Hendrix S, Mourato MP, Louro Martins L, Vangronsveld J, Cuypers A. Efficient regulation of copper homeostasis underlies accession-specific sensitivities to excess copper and cadmium in roots of Arabidopsis thaliana. JOURNAL OF PLANT PHYSIOLOGY 2021; 261:153434. [PMID: 34020275 DOI: 10.1016/j.jplph.2021.153434] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 04/13/2021] [Accepted: 04/26/2021] [Indexed: 06/12/2023]
Abstract
The commonly used Arabidopsis thaliana natural accessions Columbia (Col-0) and Wassilewskija (Ws) are known to differ in their metal sensitivity, with Col-0 being more sensitive to copper (Cu) and cadmium (Cd) than Ws. As both Cu and Cd are known to affect Cu homeostasis, it was investigated whether this process is part of an accession-specific mechanism underlying their difference in metal sensitivity. As roots are the first contact point during metal exposure, responses were compared between roots of both accessions of hydroponically grown plants exposed to excess Cu or Cd for 24 and 72 h. Root Cu levels increased in both accessions under Cu and Cd exposure. However, under Cu exposure, the downregulation of Cu transporter (COPT) genes in combination with a more pronounced upregulation of metallothionein gene MT2b indicated that Ws plants coped better with the elevated Cu concentrations. The Cd-induced disturbance in Cu homeostasis was more efficiently counteracted in roots of Ws plants than in Col-0 plants. This was indicated by a higher upregulation of the SPL7-mediated pathway, crucial in the regulation of the Cu homeostasis response. In conclusion, maintaining the Cu homeostasis response in roots is key to accession-specific differences in Cu and Cd sensitivity.
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Affiliation(s)
- Rafaela Amaral Dos Reis
- Environmental Biology, Centre for Environmental Sciences, Hasselt University, Diepenbeek, Belgium
| | - Sophie Hendrix
- Environmental Biology, Centre for Environmental Sciences, Hasselt University, Diepenbeek, Belgium; Institute of Crop Science and Resource Conservation (INRES), University of Bonn, Bonn, Germany
| | | | - Luísa Louro Martins
- LEAF, Instituto Superior de Agronomia, Universidade de Lisboa, Lisbon, Portugal
| | - Jaco Vangronsveld
- Environmental Biology, Centre for Environmental Sciences, Hasselt University, Diepenbeek, Belgium
| | - Ann Cuypers
- Environmental Biology, Centre for Environmental Sciences, Hasselt University, Diepenbeek, Belgium.
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7
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Hendrix S, Jozefczak M, Wójcik M, Deckers J, Vangronsveld J, Cuypers A. Glutathione: A key player in metal chelation, nutrient homeostasis, cell cycle regulation and the DNA damage response in cadmium-exposed Arabidopsis thaliana. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2020; 154:498-507. [PMID: 32673998 DOI: 10.1016/j.plaphy.2020.06.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2019] [Revised: 04/09/2020] [Accepted: 06/02/2020] [Indexed: 06/11/2023]
Abstract
Glutathione (GSH) is an important player in plant responses to cadmium (Cd) through its dual function as an antioxidant and precursor for metal-chelating phytochelatins (PCs). In addition, it was shown to be involved in cell cycle regulation in Arabidopsis thaliana roots, but its involvement in this process in leaves is largely unknown and has never been evaluated in Cd-exposed plants. This study aimed to elucidate the role of GSH in leaf growth and development, metal chelation, nutrient homeostasis and cell cycle regulation in A. thaliana plants upon prolonged Cd exposure. Responses were compared between wild-type (WT) plants and three GSH-deficient mutants. Our results indicate that PC production remains important in plants exposed to Cd for an extended duration. Furthermore, an important role for GSH in regulating nutrient homeostasis in Cd-exposed plants was revealed. Cell cycle analysis demonstrated that negative effects of Cd exposure on cell division and endoreplication were more pronounced in leaves of the GSH-deficient cadmium-sensitive 2-1 (cad2-1) mutant in comparison to the WT, indicating the involvement of GSH in cell cycle regulation. Finally, a crucial role for GSH in transcriptional activation of the Cd-induced DNA damage response (DDR) was revealed, as the Cd-induced upregulation of DDR-related genes was either less pronounced or completely abolished in leaves of the GSH-deficient mutants.
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Affiliation(s)
- Sophie Hendrix
- Centre for Environmental Sciences, Hasselt University, Agoralaan Building D, 3590, Diepenbeek, Belgium.
| | - Marijke Jozefczak
- Centre for Environmental Sciences, Hasselt University, Agoralaan Building D, 3590, Diepenbeek, Belgium
| | - Małgorzata Wójcik
- Department of Plant Physiology, Faculty of Biology and Biotechnology, Maria Curie-Skłodowska University, Akademicka 19, 20-033, Lublin, Poland
| | - Jana Deckers
- Centre for Environmental Sciences, Hasselt University, Agoralaan Building D, 3590, Diepenbeek, Belgium
| | - Jaco Vangronsveld
- Centre for Environmental Sciences, Hasselt University, Agoralaan Building D, 3590, Diepenbeek, Belgium
| | - Ann Cuypers
- Centre for Environmental Sciences, Hasselt University, Agoralaan Building D, 3590, Diepenbeek, Belgium
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Decou R, Delmail D, Labrousse P. Myriophyllum alterniflorum biochemical changes during in vitro Cu/Cd metal stress: Focusing on cell detoxifying enzymes. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2020; 219:105361. [PMID: 31862548 DOI: 10.1016/j.aquatox.2019.105361] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 11/14/2019] [Accepted: 11/14/2019] [Indexed: 06/10/2023]
Abstract
Given the toxicity of trace metals, their concentration, speciation and bioavailability serve to induce various plant detoxification processes, which themselves are specific to several parameters like plant species, tissue type and developmental stage. In this study, Myriophyllum alterniflorum (or alternate watermilfoil) enzyme activities (ascorbate peroxidase, catalase, glutathione peroxidase and superoxide dismutase) from in vitro cultures was measured over 27 days in response to copper (Cu) or cadmium (Cd) stress. These enzymes are unique to reactive oxygen species (ROS) scavenging (mainly hydrogen peroxide H2O2 and superoxide anion O2-) and moreover showed specific or unspecific activity profiles, depending on the metal concentrations used. Our results suggest a higher-priority protection of chloroplasts during the initial days of exposure to both metals. At the same time, the increased catalase activity could indicate an H2O2 diffusion in peroxisome in order to protect other organelles from ROS accumulation. However, as opposed to the Cd effects, high Cu concentrations appear to induce a "limited oxidative threshold" for some antioxidant enzymes, which could suggest an ion absorption competition between Cu2+ and Fe2+. In spite of an overall analysis conducted of the scavenging processes occurring in plant cells, biochemical analyses still yielded relevant indications regarding the watermilfoil strategies used for ROS management.
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Affiliation(s)
- Raphaël Decou
- University of Limoges, PEIRENE, EA 7500, F-87000 Limoges, France.
| | - David Delmail
- University of Limoges, PEIRENE, EA 7500, F-87000 Limoges, France; University of Rennes 1, UMR 6118 Géosciences, F-35043 Rennes, France
| | - Pascal Labrousse
- University of Limoges, PEIRENE, EA 7500, F-87000 Limoges, France
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9
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Wakeel A, Xu M, Gan Y. Chromium-Induced Reactive Oxygen Species Accumulation by Altering the Enzymatic Antioxidant System and Associated Cytotoxic, Genotoxic, Ultrastructural, and Photosynthetic Changes in Plants. Int J Mol Sci 2020; 21:ijms21030728. [PMID: 31979101 PMCID: PMC7037945 DOI: 10.3390/ijms21030728] [Citation(s) in RCA: 107] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 01/16/2020] [Accepted: 01/17/2020] [Indexed: 11/24/2022] Open
Abstract
Chromium (Cr) is one of the top seven toxic heavy metals, being ranked 21st among the abundantly found metals in the earth’s crust. A huge amount of Cr releases from various industries and Cr mines, which is accumulating in the agricultural land, is significantly reducing the crop development, growth, and yield. Chromium mediates phytotoxicity either by direct interaction with different plant parts and metabolic pathways or it generates internal stress by inducing the accumulation of reactive oxygen species (ROS). Thus, the role of Cr-induced ROS in the phytotoxicity is very important. In the current study, we reviewed the most recent publications regarding Cr-induced ROS, Cr-induced alteration in the enzymatic antioxidant system, Cr-induced lipid peroxidation and cell membrane damage, Cr-induced DNA damage and genotoxicity, Cr-induced ultrastructural changes in cell and subcellular level, and Cr-induced alterations in photosynthesis and photosynthetic apparatus. Taken together, we conclude that Cr-induced ROS and the suppression of the enzymatic antioxidant system actually mediate Cr-induced cytotoxic, genotoxic, ultrastructural, and photosynthetic changes in plants.
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Affiliation(s)
- Abdul Wakeel
- Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions, College of Environment and Planning, Henan University, Kaifeng 475004, China;
| | - Ming Xu
- Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions, College of Environment and Planning, Henan University, Kaifeng 475004, China;
- Correspondence: (M.X.); (Y.G.)
| | - Yinbo Gan
- Zhejiang Key Lab of Crop Germplasm, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
- Correspondence: (M.X.); (Y.G.)
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Lwalaba JLW, Louis LT, Zvobgo G, Richmond MEA, Fu L, Naz S, Mwamba M, Mundende RPM, Zhang G. Physiological and molecular mechanisms of cobalt and copper interaction in causing phyto-toxicity to two barley genotypes differing in Co tolerance. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 187:109866. [PMID: 31677568 DOI: 10.1016/j.ecoenv.2019.109866] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 10/21/2019] [Accepted: 10/23/2019] [Indexed: 05/03/2023]
Abstract
The combined effects of cobalt (Co) and copper (Cu) in their toxicity to plants is poorly studied although these two metals co-exist commonly in soil. In this study, a hydroponic experiment was carried out to investigate the effect of longer exposure of two barley genotypes differing in Co tolerance to the combined Co and Cu stress. The results confirmed the previous findings that Co accumulation in plant tissues was reduced by Cu presence, while Cu accumulation was stimulated by Co presence. Moreover, both single and combined treatments of Co and Cu reduced the mineral (Mn, Zn and K) uptake. Co and Cu applied alone or in combination at rate of 50 μM resulted in the significant reduction of plant growth and increase of oxidative stress (ROS and MDA), and meanwhile the capacity of scavenging active oxygen species (AOS) was enhanced, reflected by increased phytochelatin (PC) and glutathione (GSH and GSSG) content, as well as expression of the related genes (HvPCS1 and HvGR1). Yan66, a Co tolerant genotype was less affected in oxidative stress, and had higher AOS scavenging capacity in comparison with Ea52, a Co sensitive one. Among three HvSOD isoforms, only HvFeSOD expression was up-regulated in the combined treatment relative to control as well as the treatment of Co or Cu alone, while HvCuZnSOD and HvMnSOD were down-regulated and unaffected, respectively. In addition, the expressions of metal transporter genes (HvHMA2, HvHMA3 and HvHMA5) varied with genotype and metal treatments, with the extent being greater in Yan66 on the whole. The results suggest that upon longer exposure to the combined stress of Co and Cu, the greater phyto-toxicity than each element alone is associated with more Cu accumulation stimulated by Co and that, the higher regulation of transporter genes observed in Yan66 could in part explain for its higher metal tolerance ability.
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Affiliation(s)
- Jonas Lwalaba Wa Lwalaba
- Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, PR China; Department of Crops Sciences, Faculty of Agronomy, Université de Lubumbashi, PO Box 1825, Lubumbashi, DR, Congo
| | - Laurence Tennyson Louis
- Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, PR China
| | - Gerald Zvobgo
- Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, PR China
| | - Marvin Eusi Ambrose Richmond
- Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, PR China
| | - Liangbo Fu
- Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, PR China
| | - Shama Naz
- Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, PR China
| | - Mulembo Mwamba
- Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, PR China; Department of Crops Sciences, Faculty of Agronomy, Université de Lubumbashi, PO Box 1825, Lubumbashi, DR, Congo
| | | | - Guoping Zhang
- Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, PR China.
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11
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Yang L, Yao J, Sun J, Shi L, Chen Y, Sun J. The Ca 2+ signaling, Glu, and GABA responds to Cd stress in duckweed. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2020; 218:105352. [PMID: 31790938 DOI: 10.1016/j.aquatox.2019.105352] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 10/30/2019] [Accepted: 10/30/2019] [Indexed: 05/15/2023]
Abstract
Cadmium (Cd) affects plants and animal health seriously. Ca2+ signals in plant cells are important for adaptive responses to environmental stresses. Here we showed that 50 μM Cd shock stimulated the Ca2+ signal via modifying the instantaneous Ca2+ flux from influx of 17 pmol·cm-2·s-1 to the efflux of 240 pmol·cm-2·s-1 at 100 μm from rhizoid tip. And the Ca2+ signal transferred to the vein and mesophyll cell. The Ca addition decreased the accumulation of Cd. The gene expression of glutamate receptor-like (GLR) proteins, which is activated by Glu and triggers Ca2+ flux, was increased significantly by 24 h Cd stress. Glu content was increased under Cd stress and exogenous Glu triggered the Ca2+ signal in duckweed, while Ca2+ addition caused no influence to Glu content. GABA, which is synthesized from Glu and acts as an inhibitory neurotransmitter, has been decreased with 24 h Cd treatment. GABA addition increased the abscission rate and Glu addition decreased the abscission rate during Cd stress, suggesting that the Glu/GABA ratio is important for responding to Cd. This research shows the sight of the Glu, Ca2+, GABA signaling networks during Cd stress.
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Affiliation(s)
- Lin Yang
- Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, 300387, Tianjin, China
| | - Jie Yao
- Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, 300387, Tianjin, China
| | - Jinge Sun
- Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, 300387, Tianjin, China
| | - Leqian Shi
- Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, 300387, Tianjin, China
| | - Yikai Chen
- Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, 300387, Tianjin, China
| | - Jinsheng Sun
- Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, 300387, Tianjin, China.
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Lwalaba JLW, Louis LT, Zvobgo G, Fu L, Mwamba TM, Mukobo Mundende RP, Zhang G. Copper alleviates cobalt toxicity in barley by antagonistic interaction of the two metals. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2019; 180:234-241. [PMID: 31096127 DOI: 10.1016/j.ecoenv.2019.04.077] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 04/24/2019] [Accepted: 04/26/2019] [Indexed: 06/09/2023]
Abstract
Cobalt (Co) commonly co-exists with copper (Cu) in natural soils, but the information about their combined effects on plants is poorly available. In this study, we hydroponically investigated the combined effects of Co and Cu on two barley genotypes differing in Co toxicity tolerance to reveal the interaction pattern of these two metals. The results showed that single treatment of Co or Cu at the dose of 100 μM led to a significant decrease of growth and photosynthetic rate, and a significant increase of lipid peroxidation, ROS radicals as well as anti-oxidative enzyme (SOD, CAT and GR) activities and glutathione content, with the extent of effect being less in Yan66 than Ea52. The combined treatment of Co and Cu alleviated the toxicity of both metals in comparison with each metal treatment alone, as reflected by improved growth and photosynthesis, and much slight oxidative stress. The alleviation of metal toxicity upon combined treatment is mainly attributed to a drastic reduction of Co uptake and its translocation from roots to shoots. It may be suggested that interaction of Co and Cu on their uptake and movement in plants is antagonistic.
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Affiliation(s)
- Jonas Lwalaba Wa Lwalaba
- Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, PR China; Department of Crops Sciences, Faculty of Agronomy, Université de Lubumbashi, PO Box 1825, Lubumbashi, DR, Congo
| | - Laurence Tennyson Louis
- Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, PR China
| | - Gerald Zvobgo
- Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, PR China
| | - Liangbo Fu
- Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, PR China
| | - Theodore Mulembo Mwamba
- Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, PR China; Department of Crops Sciences, Faculty of Agronomy, Université de Lubumbashi, PO Box 1825, Lubumbashi, DR, Congo
| | | | - Guoping Zhang
- Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, PR China.
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Carvalho MEA, Piotto FA, Franco MR, Rossi ML, Martinelli AP, Cuypers A, Azevedo RA. Relationship between Mg, B and Mn status and tomato tolerance against Cd toxicity. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 240:84-92. [PMID: 30928798 DOI: 10.1016/j.jenvman.2019.03.026] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 02/25/2019] [Accepted: 03/06/2019] [Indexed: 06/09/2023]
Abstract
Distinct tomato genotypes possess different tolerance degree to cadmium (Cd), but the mechanisms behind this phenomenon are scarcely understood. To this end, the physiological, biochemical, anatomical, nutritional and molecular mechanisms associated to the plant tolerance against Cd toxicity were investigated in five tomato accessions with contrasting sensitivity to Cd exposure. Firstly, the data revealed that larger biomass loss was not always coupled to higher Cd concentration, indicating that other events, in addition to the internal Cd accumulation, impact tomato performance at early stages of Cd exposure. Secondly, the results indicated that the fine regulation of nutrient status, particularly magnesium (Mg), boron (B) and manganese (Mn), is associated to the mitigation of Cd toxicity. Magnesium status was coupled to the modulation of root development, resulting in changes in root hair formation and biomass allocation. Boron accumulation in leaves was linked to Cd toxicity, suggesting that tolerance mechanisms involved strategies to decrease or even avoid B excess in photosynthetic tissues. Disturbances in Mn status, i.e. Mn excess in leaves and Mn deficiency in roots, were also related to tomato sensitivity to Cd exposure. Thirdly, plant capacity to maintain leaf blade expansion is a relevant strategy for a better tomato development after short-term Cd exposure. Fourthly, tomato tolerance to Cd-induced stress does not depend on CAT activity enhancements in such conditions. In conclusion, tomato ability to quickly manage its nutritional status is necessary for alleviation of the Cd effects at early stages of exposure to this metal. The better understanding about tolerance mechanisms and mode of action of Cd toxicity in plants can help in the establishment of strategies to mitigate its impacts on crops.
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Affiliation(s)
- Marcia Eugenia Amaral Carvalho
- Departamento de Genética, Escola Superior de Agricultura "Luiz de Queiroz"/Universidade de São Paulo (Esalq/USP), 13418-900, Piracicaba, SP, Brazil
| | - Fernando Angelo Piotto
- Departamento de Produção Vegetal, Escola Superior de Agricultura "Luiz de Queiroz"/Universidade de São Paulo (Esalq/USP), 13418-900, Piracicaba, SP, Brazil
| | - Mônica Regina Franco
- Departamento de Genética, Escola Superior de Agricultura "Luiz de Queiroz"/Universidade de São Paulo (Esalq/USP), 13418-900, Piracicaba, SP, Brazil
| | - Mônica Lanzoni Rossi
- Divisão Produtividade Agroindustrial e Alimentos, Centro de Energia Nuclear na Agricultura/Universidade de São Paulo (Cena/USP), Av. Centenário, 303, São Dimas, 13416-000, Piracicaba, SP, Brazil
| | - Adriana Pinheiro Martinelli
- Divisão Produtividade Agroindustrial e Alimentos, Centro de Energia Nuclear na Agricultura/Universidade de São Paulo (Cena/USP), Av. Centenário, 303, São Dimas, 13416-000, Piracicaba, SP, Brazil
| | - Ann Cuypers
- Centre for Environmental Sciences, Hasselt University, Agoralaan Building D, 3590, Diepenbeek, Belgium
| | - Ricardo Antunes Azevedo
- Departamento de Genética, Escola Superior de Agricultura "Luiz de Queiroz"/Universidade de São Paulo (Esalq/USP), 13418-900, Piracicaba, SP, Brazil.
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Saad RB, Hsouna AB, Saibi W, Hamed KB, Brini F, Ghneim-Herrera T. A stress-associated protein, LmSAP, from the halophyte Lobularia maritima provides tolerance to heavy metals in tobacco through increased ROS scavenging and metal detoxification processes. JOURNAL OF PLANT PHYSIOLOGY 2018; 231:234-243. [PMID: 30312968 DOI: 10.1016/j.jplph.2018.09.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Revised: 09/25/2018] [Accepted: 09/26/2018] [Indexed: 06/08/2023]
Abstract
Agricultural soil pollution by heavy metals is a severe global ecological problem. We recently showed that overexpression of LmSAP, a member of the stress-associated protein (SAP) gene family isolated from Lobularia maritima, in transgenic tobacco led to enhanced tolerance to abiotic stress. In this study, we characterised the response of LmSAP transgenic tobacco plants to metal stresses (cadmium (Cd), copper (Cu), manganese (Mn), and zinc (Zn)). In L. maritima, LmSAP expression increased after 12 h of treatment with these metals, suggesting its involvement in the plant response to heavy metal stress. LmSAP transgenic tobacco plants subjected to these stress conditions were healthy, experienced higher seedling survival rates, and had longer roots than non-transgenic plants (NT). However, they exhibited higher tolerance towards cadmium and manganese than towards copper and zinc. LmSAP-overexpressing tobacco seedlings accumulated more cadmium, copper, and manganese compared with NT plants, but displayed markedly decreased hydrogen peroxide (H2O2) and lipid peroxidation levels after metal treatment. Activities of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) were significantly higher in transgenic plants than in NT plants after exposure to metal stress. LmSAP overexpression also enhanced the transcription of several genes encoding metallothioneins (Met1, Met2, Met3, Met4, and Met5), a copper transport protein CCH, a Cys and His-rich domain-containing protein RAR1 (Rar1), and a ubiquitin-like protein 5 (PUB1), which are involved in metal tolerance in tobacco. Our findings indicate that LmSAP overexpression in tobacco enhanced tolerance to heavy metal stress by protecting the plant cells against oxidative stress, scavenging reactive oxygen species (ROS), and decreasing the intracellular concentration of free heavy metals through its effect on metal-binding proteins in the cytosol.
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Affiliation(s)
- Rania Ben Saad
- Biotechnology and Plant Improvement Laboratory, Centre of Biotechnology of Sfax, University of Sfax, B.P "1177", 3018, Sfax, Tunisia
| | - Anis Ben Hsouna
- Biotechnology and Plant Improvement Laboratory, Centre of Biotechnology of Sfax, University of Sfax, B.P "1177", 3018, Sfax, Tunisia; Departments of Life Sciences, Faculty of Sciences of Gafsa, Zarroug, 2112, Gafsa, Tunisia
| | - Walid Saibi
- Biotechnology and Plant Improvement Laboratory, Centre of Biotechnology of Sfax, University of Sfax, B.P "1177", 3018, Sfax, Tunisia
| | - Karim Ben Hamed
- Laboratoire des Plantes Extrêmophiles, Centre de Biotechnologie de Borj Cedria, BP 901, Hammam Lif, 2050, Tunisia
| | - Faical Brini
- Biotechnology and Plant Improvement Laboratory, Centre of Biotechnology of Sfax, University of Sfax, B.P "1177", 3018, Sfax, Tunisia
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Wani W, Masoodi KZ, Zaid A, Wani SH, Shah F, Meena VS, Wani SA, Mosa KA. Engineering plants for heavy metal stress tolerance. RENDICONTI LINCEI-SCIENZE FISICHE E NATURALI 2018. [DOI: 10.1007/s12210-018-0702-y] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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16
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Amaral Dos Reis R, Keunen E, Mourato MP, Martins LL, Vangronsveld J, Cuypers A. Accession-specific life strategies affect responses in leaves of Arabidopsis thaliana plants exposed to excess Cu and Cd. JOURNAL OF PLANT PHYSIOLOGY 2018; 223:37-46. [PMID: 29471274 DOI: 10.1016/j.jplph.2018.01.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 01/20/2018] [Accepted: 01/25/2018] [Indexed: 06/08/2023]
Abstract
The natural accession Columbia (Col-0) is considered as the reference genome of the model plant Arabidopsis thaliana. Nonetheless, Col-0 plants are more sensitive to excess copper (Cu) and cadmium (Cd) than other widely used accessions such as Wassilewskija (Ws) plants. In the current study, this accession-specific metal sensitivity is further explored by comparing the responses in leaves of Col-0 and Ws plants exposed to excess Cu and Cd. Our results suggest that different life strategies favored by both accessions under physiological conditions affect their response to metal exposure. While Col-0 plants mainly invest in metal detoxification, Ws plants center on nutrient homeostasis. In particular, the higher expression of genes related to Cu homeostasis genes in non-exposed conditions indicates that Ws plants possess a constitutively efficient metal homeostasis. On the other hand, oxidative stress-related MAPK signaling appears to be boosted in leaves of Col-0 plants exposed to excess Cu. Furthermore, the upregulation of the glutathione (GSH) biosynthesis GSH2 gene and the increased GSH concentration after Cd exposure suggest the activation of detoxification mechanisms, such as phytochelatin production, to counteract the more severe Cd-induced oxidative stress in leaves of Col-0 plants. Exposure to Cd also led to a more pronounced ethylene signaling response in leaves of Col-0 as compared to Ws plants, which could be related to Cd-induced GSH metabolism. In conclusion, accession-specific life strategies clearly affect the way in which leaves of A. thaliana plants cope with excess Cu and Cd.
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Affiliation(s)
- Rafaela Amaral Dos Reis
- Environmental Biology, Centre for Environmental Sciences, Hasselt University, Diepenbeek, Belgium.
| | - Els Keunen
- Environmental Biology, Centre for Environmental Sciences, Hasselt University, Diepenbeek, Belgium.
| | - Miguel Pedro Mourato
- LEAF, Instituto Superior de Agronomia, Universidade de Lisboa, Lisbon, Portugal.
| | - Luísa Louro Martins
- LEAF, Instituto Superior de Agronomia, Universidade de Lisboa, Lisbon, Portugal.
| | - Jaco Vangronsveld
- Environmental Biology, Centre for Environmental Sciences, Hasselt University, Diepenbeek, Belgium.
| | - Ann Cuypers
- Environmental Biology, Centre for Environmental Sciences, Hasselt University, Diepenbeek, Belgium.
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Loix C, Huybrechts M, Vangronsveld J, Gielen M, Keunen E, Cuypers A. Reciprocal Interactions between Cadmium-Induced Cell Wall Responses and Oxidative Stress in Plants. FRONTIERS IN PLANT SCIENCE 2017; 8:1867. [PMID: 29163592 PMCID: PMC5671638 DOI: 10.3389/fpls.2017.01867] [Citation(s) in RCA: 148] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 10/12/2017] [Indexed: 05/18/2023]
Abstract
Cadmium (Cd) pollution renders many soils across the world unsuited or unsafe for food- or feed-orientated agriculture. The main mechanism of Cd phytotoxicity is the induction of oxidative stress, amongst others through the depletion of glutathione. Oxidative stress can damage lipids, proteins, and nucleic acids, leading to growth inhibition or even cell death. The plant cell has a variety of tools to defend itself against Cd stress. First and foremost, cell walls might prevent Cd from entering and damaging the protoplast. Both the primary and secondary cell wall have an array of defensive mechanisms that can be adapted to cope with Cd. Pectin, which contains most of the negative charges within the primary cell wall, can sequester Cd very effectively. In the secondary cell wall, lignification can serve to immobilize Cd and create a tougher barrier for entry. Changes in cell wall composition are, however, dependent on nutrients and conversely might affect their uptake. Additionally, the role of ascorbate (AsA) as most important apoplastic antioxidant is of considerable interest, due to the fact that oxidative stress is a major mechanism underlying Cd toxicity, and that AsA biosynthesis shares several links with cell wall construction. In this review, modifications of the plant cell wall in response to Cd exposure are discussed. Focus lies on pectin in the primary cell wall, lignification in the secondary cell wall and the importance of AsA in the apoplast. Regarding lignification, we attempt to answer the question whether increased lignification is merely a consequence of Cd toxicity, or rather an elicited defense response. We propose a model for lignification as defense response, with a central role for hydrogen peroxide as substrate and signaling molecule.
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Affiliation(s)
| | | | | | | | | | - Ann Cuypers
- Environmental Biology, Centre for Environmental Sciences, Hasselt University, Diepenbeek, Belgium
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