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Piccinini L, Nirina Ramamonjy F, Ursache R. Imaging plant cell walls using fluorescent stains: The beauty is in the details. J Microsc 2024; 295:102-120. [PMID: 38477035 DOI: 10.1111/jmi.13289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 02/23/2024] [Accepted: 02/29/2024] [Indexed: 03/14/2024]
Abstract
Plants continuously face various environmental stressors throughout their lifetime. To be able to grow and adapt in different environments, they developed specialized tissues that allowed them to maintain a protected yet interconnected body. These tissues undergo specific primary and secondary cell wall modifications that are essential to ensure normal plant growth, adaptation and successful land colonization. The composition of cell walls can vary among different plant species, organs and tissues. The ability to remodel their cell walls is fundamental for plants to be able to cope with multiple biotic and abiotic stressors. A better understanding of the changes taking place in plant cell walls may help identify and develop new strategies as well as tools to enhance plants' survival under environmental stresses or prevent pathogen attack. Since the invention of microscopy, numerous imaging techniques have been developed to determine the composition and dynamics of plant cell walls during normal growth and in response to environmental stimuli. In this review, we discuss the main advances in imaging plant cell walls, with a particular focus on fluorescent stains for different cell wall components and their compatibility with tissue clearing techniques. Lay Description: Plants are continuously subjected to various environmental stresses during their lifespan. They evolved specialized tissues that thrive in different environments, enabling them to maintain a protected yet interconnected body. Such tissues undergo distinct primary and secondary cell wall alterations essential to normal plant growth, their adaptability and successful land colonization. Cell wall composition may differ among various plant species, organs and even tissues. To deal with various biotic and abiotic stresses, plants must have the capacity to remodel their cell walls. Gaining insight into changes that take place in plant cell walls will help identify and create novel tools and strategies to improve plants' ability to withstand environmental challenges. Multiple imaging techniques have been developed since the introduction of microscopy to analyse the composition and dynamics of plant cell walls during growth and in response to environmental changes. Advancements in plant tissue cleaning procedures and their compatibility with cell wall stains have significantly enhanced our ability to perform high-resolution cell wall imaging. At the same time, several factors influence the effectiveness of cleaning and staining plant specimens, as well as the time necessary for the process, including the specimen's size, thickness, tissue complexity and the presence of autofluorescence. In this review, we will discuss the major advances in imaging plant cell walls, with a particular emphasis on fluorescent stains for diverse cell wall components and their compatibility with tissue clearing techniques. We hope that this review will assist readers in selecting the most appropriate stain or combination of stains to highlight specific cell wall components of interest.
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Affiliation(s)
- Luca Piccinini
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Bellaterra, Barcelona, Spain
| | - Fabien Nirina Ramamonjy
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Bellaterra, Barcelona, Spain
| | - Robertas Ursache
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Bellaterra, Barcelona, Spain
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Li G, Wu J, Kronzucker HJ, Li B, Shi W. Physiological and molecular mechanisms of plant-root responses to iron toxicity. JOURNAL OF PLANT PHYSIOLOGY 2024; 297:154257. [PMID: 38688043 DOI: 10.1016/j.jplph.2024.154257] [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: 03/29/2024] [Revised: 04/17/2024] [Accepted: 04/22/2024] [Indexed: 05/02/2024]
Abstract
The chemical form and physiological activity of iron (Fe) in soil are dependent on soil pH and redox potential (Eh), and Fe levels in soils are frequently elevated to the point of causing Fe toxicity in plants, with inhibition of normal physiological activities and of growth and development. In this review, we describe how iron toxicity triggers important physiological changes, including nitric-oxide (NO)-mediated potassium (K+) efflux at the tips of roots and accumulation of reactive oxygen species (ROS) and reactive nitrogen (RNS) in roots, resulting in physiological stress. We focus on the root system, as the first point of contact with Fe in soil, and describe the key processes engaged in Fe transport, distribution, binding, and other mechanisms that are drawn upon to defend against high-Fe stress. We describe the root-system regulation of key physiological processes and of morphological development through signaling substances such as ethylene, auxin, reactive oxygen species, and nitric oxide, and discuss gene-expression responses under high Fe. We especially focus on studies on the physiological and molecular mechanisms in rice and Arabidopsis under high Fe, hoping to provide a valuable theoretical basis for improving the ability of crop roots to adapt to soil Fe toxicity.
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Affiliation(s)
- Guangjie Li
- State Key Laboratory of Nutrient Use and Management, Institute of Agricultural Resources and Environment, Shandong Academy of Agricultural Sciences, Jinan, 250100, China.
| | - Jinlin Wu
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China; University of the Chinese Academy of Sciences, No. 19(A) Yuquan Road, Shijingshan District, Beijing, 100049, China
| | - Herbert J Kronzucker
- School of BioSciences, The University of Melbourne, Parkville, VIC, 3010, Australia.
| | - Baohai Li
- MOE Key Laboratory of Environment Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang, China.
| | - Weiming Shi
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China; International Research Centre for Environmental Membrane Biology, Foshan University, Foshan, 528000, China; University of the Chinese Academy of Sciences, No. 19(A) Yuquan Road, Shijingshan District, Beijing, 100049, China.
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Fu S, Iqbal B, Li G, Alabbosh KF, Khan KA, Zhao X, Raheem A, Du D. The role of microbial partners in heavy metal metabolism in plants: a review. PLANT CELL REPORTS 2024; 43:111. [PMID: 38568247 DOI: 10.1007/s00299-024-03194-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Accepted: 03/06/2024] [Indexed: 04/05/2024]
Abstract
Heavy metal pollution threatens plant growth and development as well as ecological stability. Here, we synthesize current research on the interplay between plants and their microbial symbionts under heavy metal stress, highlighting the mechanisms employed by microbes to enhance plant tolerance and resilience. Several key strategies such as bioavailability alteration, chelation, detoxification, induced systemic tolerance, horizontal gene transfer, and methylation and demethylation, are examined, alongside the genetic and molecular basis governing these plant-microbe interactions. However, the complexity of plant-microbe interactions, coupled with our limited understanding of the associated mechanisms, presents challenges in their practical application. Thus, this review underscores the necessity of a more detailed understanding of how plants and microbes interact and the importance of using a combined approach from different scientific fields to maximize the benefits of these microbial processes. By advancing our knowledge of plant-microbe synergies in the metabolism of heavy metals, we can develop more effective bioremediation strategies to combat the contamination of soil by heavy metals.
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Affiliation(s)
- Shilin Fu
- School of Environment and Safety Engineering, School of Emergency Management, Jiangsu Province Engineering Research Centre of Green Technology and Contingency Management for Emerging Pollutants, Jiangsu University, 212013, Zhenjiang, People's Republic of China
| | - Babar Iqbal
- School of Environment and Safety Engineering, School of Emergency Management, Jiangsu Province Engineering Research Centre of Green Technology and Contingency Management for Emerging Pollutants, Jiangsu University, 212013, Zhenjiang, People's Republic of China
| | - Guanlin Li
- School of Environment and Safety Engineering, School of Emergency Management, Jiangsu Province Engineering Research Centre of Green Technology and Contingency Management for Emerging Pollutants, Jiangsu University, 212013, Zhenjiang, People's Republic of China.
- Jiangsu Collaborative Innovation Centre of Technology and Material of Water Treatment, Suzhou University of Science and Technology, 215009, Suzhou, People's Republic of China.
| | | | - Khalid Ali Khan
- Applied College, Center of Bee Research and its Products (CBRP), Unit of Bee Research and Honey Production, and Research Center for Advanced Materials Science (RCAMS), King Khalid University, 61413, Abha, Saudi Arabia
| | - Xin Zhao
- Department of Civil and Environmental Engineering, College of Engineering, Seoul National University, Seoul, 08826, Republic of Korea
| | - Abdulkareem Raheem
- School of Environment and Safety Engineering, School of Emergency Management, Jiangsu Province Engineering Research Centre of Green Technology and Contingency Management for Emerging Pollutants, Jiangsu University, 212013, Zhenjiang, People's Republic of China.
| | - Daolin Du
- Jingjiang College, Institute of Environment and Ecology, School of Emergency Management, School of Environment and Safety Engineering, School of Agricultural Engineering, Jiangsu University, 212013, Zhenjiang, People's Republic of China.
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Murgia I, Morandini P. Plant Iron Research in African Countries: Current "Hot Spots", Approaches, and Potentialities. PLANTS (BASEL, SWITZERLAND) 2023; 13:14. [PMID: 38202322 PMCID: PMC10780554 DOI: 10.3390/plants13010014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 12/14/2023] [Accepted: 12/17/2023] [Indexed: 01/12/2024]
Abstract
Plant iron (Fe) nutrition and metabolism is a fascinating and challenging research topic; understanding the role of Fe in the life cycle of plants requires knowledge of Fe chemistry and biochemistry and their impact during development. Plant Fe nutritional status is dependent on several factors, including the surrounding biotic and abiotic environments, and influences crop yield and the nutritional quality of edible parts. The relevance of plant Fe research will further increase globally, particularly for Africa, which is expected to reach 2.5 billion people by 2050. The aim of this review is to provide an updated picture of plant Fe research conducted in African countries to favor its dissemination within the scientific community. Three main research hotspots have emerged, and all of them are related to the production of plants of superior quality, i.e., development of Fe-dense crops, development of varieties resilient to Fe toxicity, and alleviation of Fe deficiency, by means of Fe nanoparticles for sustainable agriculture. An intensification of research collaborations between the African research groups and plant Fe groups worldwide would be beneficial for the progression of the identified research topics.
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Affiliation(s)
- Irene Murgia
- Department of Environmental Science and Policy, Università degli Studi di Milano, Via Celoria 10, 20133 Milan, Italy;
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Chen Y, Liu Y, Ge J, Li R, Zhang R, Zhang Y, Huo Z, Xu K, Wei H, Dai Q. Improved physiological and morphological traits of root synergistically enhanced salinity tolerance in rice under appropriate nitrogen application rate. FRONTIERS IN PLANT SCIENCE 2022; 13:982637. [PMID: 35968148 PMCID: PMC9372507 DOI: 10.3389/fpls.2022.982637] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 07/15/2022] [Indexed: 06/15/2023]
Abstract
Numerous papers studied the relations between nitrogen rate and rice yield in saline soils, whereas the rice root morphological and physiological characteristics mediating nitrogen rates in yield formation under varied salinity levels remain less concerns. Through a field experiment applied with five nitrogen rates (0, 210, 255, 300, 345, and 390 kg ha-1) in saline land, we found that rice yield peaked at 7.7 t ha-1 under 300 kg ha-1 nitrogen, and excessive N was not conductive for increasing yield. To further elucidate its internal physiological mechanism, a pot experiment was designed with three N rates (210 [N1], 300 [N2], 390 [N3] kg ha-1) and three salt concentrations (0 [S0], 1.5 [S1], 3.0 [S2] g kg-1 NaCl). Results showed that the average grain yield was decreased by 19.1 and 51.1% under S1 and S2, respectively, while notably increased by 18.5 and 14.5% under N2 and N3, respectively. Salinity stress significantly inhibited root biomass, root length and surface area, root oxidation capacity (ROC), K+ and K+/Na+ ratio, and nitrogen metabolism-related enzyme activities, whereas root Na+ and antioxidant enzyme activities were notably increased. The mechanism of how insufficient N supply (N1) affected rice yield formation was consistent at different salinity levels, which displayed adverse impacts on root morphological and physiological traits, thereby significantly inhibiting leaf photosynthesis and grain yield of rice. However, the mechanism thorough which excessive N (N3) affected yield formation was quite different under varied salinity levels. Under lower salinity (S0 and S1), no significant differences on root morphological traits and grain yield were observed except the significantly decline in activities of NR and GS between N3 and N2 treatments. Under higher salinity level (S2), the decreased ROC, K+/Na+ ratio due to increased Na+, antioxidant enzyme activities, and NR and GS activities were the main reason leading to undesirable root morphological traits and leaf photosynthesis, which further triggered decreased grain yield under N3 treatment, compared to that under N2 treatment. Overall, our results suggest that improved physiological and morphological traits of root synergistically enhanced salinity tolerance in rice under appropriate nitrogen application rate.
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Affiliation(s)
- Yinglong Chen
- Key Laboratory of Saline-Alkali Soil Improvement and Utilization (Coastal Saline-Alkali Lands), Jiangsu Key Laboratory of Crop Genetics and Physiology, Jiangsu Key Laboratory of Crop Cultivation and Physiology, Ministry of Agriculture and Rural Affairs, Jiangsu Co-innovation Center for Modern Production Technology of Grain Crops, Research Institute of Rice Industrial Engineering Technology, Yangzhou University, Yangzhou, China
| | - Yang Liu
- Key Laboratory of Saline-Alkali Soil Improvement and Utilization (Coastal Saline-Alkali Lands), Jiangsu Key Laboratory of Crop Genetics and Physiology, Jiangsu Key Laboratory of Crop Cultivation and Physiology, Ministry of Agriculture and Rural Affairs, Jiangsu Co-innovation Center for Modern Production Technology of Grain Crops, Research Institute of Rice Industrial Engineering Technology, Yangzhou University, Yangzhou, China
| | - Jianfei Ge
- Key Laboratory of Saline-Alkali Soil Improvement and Utilization (Coastal Saline-Alkali Lands), Jiangsu Key Laboratory of Crop Genetics and Physiology, Jiangsu Key Laboratory of Crop Cultivation and Physiology, Ministry of Agriculture and Rural Affairs, Jiangsu Co-innovation Center for Modern Production Technology of Grain Crops, Research Institute of Rice Industrial Engineering Technology, Yangzhou University, Yangzhou, China
| | - Rongkai Li
- Key Laboratory of Saline-Alkali Soil Improvement and Utilization (Coastal Saline-Alkali Lands), Jiangsu Key Laboratory of Crop Genetics and Physiology, Jiangsu Key Laboratory of Crop Cultivation and Physiology, Ministry of Agriculture and Rural Affairs, Jiangsu Co-innovation Center for Modern Production Technology of Grain Crops, Research Institute of Rice Industrial Engineering Technology, Yangzhou University, Yangzhou, China
| | - Rui Zhang
- Key Laboratory of Saline-Alkali Soil Improvement and Utilization (Coastal Saline-Alkali Lands), Jiangsu Key Laboratory of Crop Genetics and Physiology, Jiangsu Key Laboratory of Crop Cultivation and Physiology, Ministry of Agriculture and Rural Affairs, Jiangsu Co-innovation Center for Modern Production Technology of Grain Crops, Research Institute of Rice Industrial Engineering Technology, Yangzhou University, Yangzhou, China
| | - Yang Zhang
- College of Environmental Science and Engineering, Yangzhou University, Yangzhou, China
| | - Zhongyang Huo
- Key Laboratory of Saline-Alkali Soil Improvement and Utilization (Coastal Saline-Alkali Lands), Jiangsu Key Laboratory of Crop Genetics and Physiology, Jiangsu Key Laboratory of Crop Cultivation and Physiology, Ministry of Agriculture and Rural Affairs, Jiangsu Co-innovation Center for Modern Production Technology of Grain Crops, Research Institute of Rice Industrial Engineering Technology, Yangzhou University, Yangzhou, China
| | - Ke Xu
- Key Laboratory of Saline-Alkali Soil Improvement and Utilization (Coastal Saline-Alkali Lands), Jiangsu Key Laboratory of Crop Genetics and Physiology, Jiangsu Key Laboratory of Crop Cultivation and Physiology, Ministry of Agriculture and Rural Affairs, Jiangsu Co-innovation Center for Modern Production Technology of Grain Crops, Research Institute of Rice Industrial Engineering Technology, Yangzhou University, Yangzhou, China
| | - Huanhe Wei
- Key Laboratory of Saline-Alkali Soil Improvement and Utilization (Coastal Saline-Alkali Lands), Jiangsu Key Laboratory of Crop Genetics and Physiology, Jiangsu Key Laboratory of Crop Cultivation and Physiology, Ministry of Agriculture and Rural Affairs, Jiangsu Co-innovation Center for Modern Production Technology of Grain Crops, Research Institute of Rice Industrial Engineering Technology, Yangzhou University, Yangzhou, China
| | - Qigen Dai
- Key Laboratory of Saline-Alkali Soil Improvement and Utilization (Coastal Saline-Alkali Lands), Jiangsu Key Laboratory of Crop Genetics and Physiology, Jiangsu Key Laboratory of Crop Cultivation and Physiology, Ministry of Agriculture and Rural Affairs, Jiangsu Co-innovation Center for Modern Production Technology of Grain Crops, Research Institute of Rice Industrial Engineering Technology, Yangzhou University, Yangzhou, China
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Genome-Wide Identification of Cassava Glyoxalase I Genes and the Potential Function of MeGLYⅠ-13 in Iron Toxicity Tolerance. Int J Mol Sci 2022; 23:ijms23095212. [PMID: 35563603 PMCID: PMC9104206 DOI: 10.3390/ijms23095212] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 05/03/2022] [Accepted: 05/04/2022] [Indexed: 02/01/2023] Open
Abstract
Glyoxalase I (GLYI) is a key enzyme in the pathway of the glyoxalase system that degrades the toxic substance methylglyoxal, which plays a crucial part in plant growth, development, and stress response. A total of 19 GLYI genes were identified from the cassava genome, which distributed randomly on 11 chromosomes. These genes were named MeGLYI-1–19 and were systematically characterized. Transcriptome data analysis showed that MeGLYIs gene expression is tissue-specific, and MeGLYI-13 is the dominant gene expressed in young tissues, while MeGLYI-19 is the dominant gene expressed in mature tissues and organs. qRT-PCR analysis showed that MeGLYI-13 is upregulated under 2 h excess iron stress, but downregulated under 6, 12, and 20 h iron stress. Overexpression of MeGLYI-13 enhanced the growth ability of transgenic yeast under iron stress. The root growth of transgenic Arabidopsis seedlings was less inhibited by iron toxicity than that of the wild type (WT). Potted transgenic Arabidopsis blossomed and podded under iron stress, but flowering of the WT was significantly delayed. The GLYI activity in transgenic Arabidopsis was improved under both non-iron stress and iron stress conditions compared to the WT. The SOD activity in transgenic plants was increased under iron stress, while the POD and CAT activity and MDA content were decreased compared to that in the WT. These results provide a basis for the selection of candidate genes for iron toxicity tolerance in cassava, and lay a theoretical foundation for further studies on the functions of these MeGLYI genes.
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Yan L, Wang X, Ji X, Peng B. Depletion of bioavailable As/Cd with rice plant from paddy soils of high contamination risk. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 289:117951. [PMID: 34426184 DOI: 10.1016/j.envpol.2021.117951] [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: 05/24/2021] [Revised: 08/02/2021] [Accepted: 08/10/2021] [Indexed: 06/13/2023]
Abstract
Co-uptake and high accumulation of As and Cd by rice is an outstanding issue threatening public health. From the viewpoint of soil cleanup, however, efficient As/Cd extraction by this paddy-adapted plant, followed by biomass removal, could provide a major pathway depleting As/Cd accumulation in paddy soils and thus inhibiting their transfer in food chain. Here a field trial was performed to identify the significance of As/Cd cleanup from paddy soil by rice. 88 % and 51 % of total extracted As and Cd were retained in root. To eliminate specifically rice-available As/Cd pool and obstruct their cycling back to soil, one crop of rice root was removed, leading to the depletion of 46 % and 69 % of plant available As (soluble & exchangeable) and Cd (exchangeable & carbonate-bound), respectively. In the following cultivation on the post-cleanup field, polished rice As fell from 0.23 mg kg-1 to 0.12 mg kg-1, markedly lower than the Chinese (WHO) limit (0.2 mg kg-1). Meanwhile, white rice Cd decreased by 24 %. This field work identified that As/Cd co-extraction by paddy-adapted rice plant, followed by root removal, as a primary step toward rice safety in areas with high contamination risk but little reserved paddy resources.
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Affiliation(s)
- Lu Yan
- School of Geographic Sciences, Hunan Normal University, Changsha, Hunan, 410081, China; Key Laboratory of Environmental Heavy-Metal Contamination and Ecological Remediation, Hunan Normal University, Changsha, Hunan, 410081, China
| | - Xin Wang
- School of Geographic Sciences, Hunan Normal University, Changsha, Hunan, 410081, China; Key Laboratory of Environmental Heavy-Metal Contamination and Ecological Remediation, Hunan Normal University, Changsha, Hunan, 410081, China.
| | - Xionghui Ji
- Longping Branch of Graduate School of Hunan University, Changsha, 410125, China; Key Lab of Prevention, Control and Remediation of Soil Heavy Metal Pollution, Hunan Institute of Agro-Environment and Ecology, Hunan Academy of Agricultural Sciences, Changsha, 410125, China; Ministry of Agriculture Key Lab of Agri-Environment in the Midstream of Yangtze River Plain, Changsha, 410125, China
| | - Bo Peng
- School of Geographic Sciences, Hunan Normal University, Changsha, Hunan, 410081, China; Key Laboratory of Environmental Heavy-Metal Contamination and Ecological Remediation, Hunan Normal University, Changsha, Hunan, 410081, China
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Kaur R, Das S, Bansal S, Singh G, Sardar S, Dhar H, Ram H. Heavy metal stress in rice: Uptake, transport, signaling, and tolerance mechanisms. PHYSIOLOGIA PLANTARUM 2021; 173:430-448. [PMID: 34227684 DOI: 10.1111/ppl.13491] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 05/06/2021] [Accepted: 06/30/2021] [Indexed: 06/13/2023]
Abstract
Heavy metal contamination of agricultural fields has become a global concern as it causes a direct impact on human health. Rice is the major food crop for almost half of the world population and is grown under diverse environmental conditions, including heavy metal-contaminated soil. In recent years, the impact of heavy metal contamination on rice yield and grain quality has been shown through multiple approaches. In this review article, different aspects of heavy metal stress, that is uptake, transport, signaling and tolerance mechanisms, are comprehensively discussed with special emphasis on rice. For uptake, some of the transporters have specificity to one or two metal ions, whereas many other transporters are able to transport many different ions. After uptake, the intercellular signaling is mediated through different signaling pathways involving the regulation of various hormones, alteration of calcium levels, and the activation of mitogen-activated protein kinases. Heavy metal stress signals from various intermediate molecules activate various transcription factors, which triggers the expression of various antioxidant enzymes. Activated antioxidant enzymes then scavenge various reactive oxygen species, which eventually leads to stress tolerance in plants. Non-enzymatic antioxidants, such as ascorbate, metalloids, and even metal-binding peptides (metallothionein and phytochelatin) can also help to reduce metal toxicity in plants. Genetic engineering has been successfully used in rice and many other crops to increase metal tolerance and reduce heavy metals accumulation. A comprehensive understanding of uptake, transport, signaling, and tolerance mechanisms will help to grow rice plants in agricultural fields with less heavy metal accumulation in grains.
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Affiliation(s)
- Ravneet Kaur
- Agricultural Biotechnology division, National Agri-Food Biotechnology Institute (NABI), Mohali, India
| | - Susmita Das
- Plant Physiology and Biochemistry Laboratory, Department of Botany, University of Calcutta, Kolkata, India
| | - Sakshi Bansal
- Agricultural Biotechnology division, National Agri-Food Biotechnology Institute (NABI), Mohali, India
| | - Gurbir Singh
- Agricultural Biotechnology division, National Agri-Food Biotechnology Institute (NABI), Mohali, India
| | - Shaswati Sardar
- Lab 202, National Institute of Plant Genome Research (NIPGR), New Delhi, India
| | - Hena Dhar
- Agricultural Biotechnology division, National Agri-Food Biotechnology Institute (NABI), Mohali, India
| | - Hasthi Ram
- Lab 202, National Institute of Plant Genome Research (NIPGR), New Delhi, India
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