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El Yamani M, Cordovilla MDP. Tolerance Mechanisms of Olive Tree ( Olea europaea) under Saline Conditions. PLANTS (BASEL, SWITZERLAND) 2024; 13:2094. [PMID: 39124213 PMCID: PMC11314443 DOI: 10.3390/plants13152094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2024] [Revised: 07/19/2024] [Accepted: 07/20/2024] [Indexed: 08/12/2024]
Abstract
The olive tree (Olea europaea L.) is an evergreen tree that occupies 19% of the woody crop area and is cultivated in 67 countries on five continents. The largest olive production region is concentrated in the Mediterranean basin, where the olive tree has had an enormous economic, cultural, and environmental impact since the 7th century BC. In the Mediterranean region, salinity stands out as one of the main abiotic stress factors significantly affecting agricultural production. Moreover, climate change is expected to lead to increased salinization in this region, threatening olive productivity. Salt stress causes combined damage by osmotic stress and ionic toxicity, restricting olive growth and interfering with multiple metabolic processes. A large variability in salinity tolerance among olive cultivars has been described. This paper aims to synthesize information from the published literature on olive adaptations to salt stress and its importance in salinity tolerance. The morphological, physiological, biochemical, and molecular mechanisms of olive tolerance to salt stress are reviewed.
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Affiliation(s)
- Mohamed El Yamani
- Laboratory of Applied Sciences for the Environment and Sustainable Development, Essaouira School of Technology, Cadi Ayyad University, B.P. 383, Essaouira 40000, Morocco
| | - María del Pilar Cordovilla
- Center for Advances Studies in Olive Grove and Olive Oils, Faculty of Experimental Science, University of Jaén, Paraje Las Lagunillas, E-23071 Jaén, Spain
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2
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Sha S, Wang G, Liu J, Wang M, Wang L, Liu Y, Geng G, Liu J, Wang Y. Regulation of photosynthetic function and reactive oxygen species metabolism in sugar beet (Beta vulgaris L.) cultivars under waterlogging stress and associated tolerance mechanisms. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2024; 210:108651. [PMID: 38653098 DOI: 10.1016/j.plaphy.2024.108651] [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: 01/20/2024] [Revised: 03/31/2024] [Accepted: 04/19/2024] [Indexed: 04/25/2024]
Abstract
Sugar beet (Beta vulgaris L.) is an economically important sugar crop worldwide that is susceptible to sudden waterlogging stress during seedling cultivation, which poses a major threat to sugar beet development and production. Our understanding of the physiological basis of waterlogging tolerance in sugar beet is limited. To investigate the photosynthetic adaptation strategies of sugar beet to waterlogging stress conditions, the tolerant cultivar KUHN1260 (KU) and sensitive cultivar SV1433 (SV) were grown under waterlogging stress, and their photosynthetic function and reactive oxygen species (ROS) metabolism were assessed. Our results showed that waterlogging stress significantly reduced the photosynthetic pigment content, rubisco activity, and expression level of the photosynthetic enzyme genes SvRuBP, SvGAPDH, and SvPRK, gas exchange parameters, and chlorophyll fluorescence parameters, induced damage to the ultrastructure of the chloroplast of the two sugar beet cultivars, inhibited the photosynthetic carbon assimilation capacity of sugar beet leaves, damaged the structural stability of photosystem II (PSII), and disturbed the equilibrium between electrons at the acceptor and donor sides of PSII, which was the result of stomatal and non-stomatal limiting factors. Moreover, the level of ROS, H2O2, and O2▪-, antioxidant enzyme activity, and gene expression levels in the leaves of the two sugar beet cultivars increased over time under waterlogging stress; ROS accumulation was lower and antioxidant enzyme activities and gene expression levels were higher in the waterlogging-tolerant cultivar (KU) than the waterlogging-sensitive cultivar (SV). In sum, these responses in the more tolerant cultivars are associated with their resistance to waterlogging stress. Our findings will aid the breeding of waterlogging-tolerant sugar beet cultivars.
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Affiliation(s)
- Shanshan Sha
- Engineering Research Center of Agricultural Microbiology Technology, Ministry of Education & Heilongjiang Provincial Key Laboratory of Ecological Restoration and Resource Utilization for Cold Region & School of Life Sciences, Heilongjiang University, Harbin, 150080, China; School of Food Engineering, Harbin University, Harbin, 150000, China
| | - Gang Wang
- Engineering Research Center of Agricultural Microbiology Technology, Ministry of Education & Heilongjiang Provincial Key Laboratory of Ecological Restoration and Resource Utilization for Cold Region & School of Life Sciences, Heilongjiang University, Harbin, 150080, China
| | - Jinling Liu
- Engineering Research Center of Agricultural Microbiology Technology, Ministry of Education & Heilongjiang Provincial Key Laboratory of Ecological Restoration and Resource Utilization for Cold Region & School of Life Sciences, Heilongjiang University, Harbin, 150080, China; National Sugar Crop Improvement Centre, College of Advanced Agriculture and Ecological Environment, Heilongjiang University, Harbin, 150080, China; Heilongjiang Sugar Beet Engineering Technology Research Center, College of Advanced Agriculture and Ecological Environment, Heilongjiang University, Harbin, 150080, China
| | - Meihui Wang
- Engineering Research Center of Agricultural Microbiology Technology, Ministry of Education & Heilongjiang Provincial Key Laboratory of Ecological Restoration and Resource Utilization for Cold Region & School of Life Sciences, Heilongjiang University, Harbin, 150080, China; National Sugar Crop Improvement Centre, College of Advanced Agriculture and Ecological Environment, Heilongjiang University, Harbin, 150080, China; Heilongjiang Sugar Beet Engineering Technology Research Center, College of Advanced Agriculture and Ecological Environment, Heilongjiang University, Harbin, 150080, China
| | - Lihua Wang
- Engineering Research Center of Agricultural Microbiology Technology, Ministry of Education & Heilongjiang Provincial Key Laboratory of Ecological Restoration and Resource Utilization for Cold Region & School of Life Sciences, Heilongjiang University, Harbin, 150080, China
| | - Yonglong Liu
- Engineering Research Center of Agricultural Microbiology Technology, Ministry of Education & Heilongjiang Provincial Key Laboratory of Ecological Restoration and Resource Utilization for Cold Region & School of Life Sciences, Heilongjiang University, Harbin, 150080, China; National Sugar Crop Improvement Centre, College of Advanced Agriculture and Ecological Environment, Heilongjiang University, Harbin, 150080, China; Heilongjiang Sugar Beet Engineering Technology Research Center, College of Advanced Agriculture and Ecological Environment, Heilongjiang University, Harbin, 150080, China
| | - Gui Geng
- Engineering Research Center of Agricultural Microbiology Technology, Ministry of Education & Heilongjiang Provincial Key Laboratory of Ecological Restoration and Resource Utilization for Cold Region & School of Life Sciences, Heilongjiang University, Harbin, 150080, China; National Sugar Crop Improvement Centre, College of Advanced Agriculture and Ecological Environment, Heilongjiang University, Harbin, 150080, China; Heilongjiang Sugar Beet Engineering Technology Research Center, College of Advanced Agriculture and Ecological Environment, Heilongjiang University, Harbin, 150080, China.
| | - Jiahui Liu
- Engineering Research Center of Agricultural Microbiology Technology, Ministry of Education & Heilongjiang Provincial Key Laboratory of Ecological Restoration and Resource Utilization for Cold Region & School of Life Sciences, Heilongjiang University, Harbin, 150080, China; National Sugar Crop Improvement Centre, College of Advanced Agriculture and Ecological Environment, Heilongjiang University, Harbin, 150080, China; Heilongjiang Sugar Beet Engineering Technology Research Center, College of Advanced Agriculture and Ecological Environment, Heilongjiang University, Harbin, 150080, China
| | - Yuguang Wang
- Engineering Research Center of Agricultural Microbiology Technology, Ministry of Education & Heilongjiang Provincial Key Laboratory of Ecological Restoration and Resource Utilization for Cold Region & School of Life Sciences, Heilongjiang University, Harbin, 150080, China; National Sugar Crop Improvement Centre, College of Advanced Agriculture and Ecological Environment, Heilongjiang University, Harbin, 150080, China; Heilongjiang Sugar Beet Engineering Technology Research Center, College of Advanced Agriculture and Ecological Environment, Heilongjiang University, Harbin, 150080, China.
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3
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Boussadia O, Zgallai H, Mzid N, Zaabar R, Braham M, Doupis G, Koubouris G. Physiological Responses of Two Olive Cultivars to Salt Stress. PLANTS (BASEL, SWITZERLAND) 2023; 12:1926. [PMID: 37653843 PMCID: PMC10222188 DOI: 10.3390/plants12101926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 04/26/2023] [Accepted: 04/27/2023] [Indexed: 09/02/2023]
Abstract
The olive tree (Olea europaea L.) is the main fruit tree in most of the arid and semi-arid regions of Tunisia, which is where the problem of salinity is more pronounced. Salinity is one of the main factors that affects the productivity of olive trees, so the objective of this experiment was to study the effects of salinity on the photosynthesis, water relations, mineral status, and enzymatic activity of two cultivars of Olea europaea L., 'Chemlali' and 'Koroneiki'. The trial was conducted under controlled conditions in a greenhouse for a period of 49 days and included two treatments: T0 control and T100 (irrigation with 100 mM of NaCl solution). Under salinity stress, the photosynthesis, stomatal conductance, and leaves of both cultivars were negatively affected. 'Chemlali' showed greater tolerance to NaCl salinity, based on a progressive decrease in osmotic potential (Ψπ) followed by a progressive and synchronous decrease in gs, without a comparable decrease in photosynthesis. The water use efficiency (WUE) improved as a result. In addition, the K+/Na+ ratio in 'Chemlali' rose. This appears to be crucial for managing stress. Conversely, enzymatic activity showed an accumulation of glutathione peroxidase (GPX) in stressed plants. The catalase (CAT) and ascorbate peroxidase (APX) content decreased in both stressed varieties. It can be concluded that the cultivar 'Koroneiki' is more susceptible to salt stress than the cultivar 'Chemlali', because the accumulation of GPX and the decreases in CAT and APX were more pronounced in this cultivar.
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Affiliation(s)
- Olfa Boussadia
- Olive Institute, Ibn Khaldoun BP 14, Sousse 4061, Tunisia
| | - Hatem Zgallai
- National Institute of Agronomic Research of Tunisia, Rue Hedi Karray, Tunis 1004, Tunisia
| | - Nada Mzid
- Department of Agriculture Forestry and Nature (DAFNE), University of Tuscia, 01100 Viterbo, Italy
| | - Rihem Zaabar
- Olive Institute, Ibn Khaldoun BP 14, Sousse 4061, Tunisia
| | - Mohamed Braham
- Olive Institute, Ibn Khaldoun BP 14, Sousse 4061, Tunisia
| | - Georgios Doupis
- Laboratory of Olive Cultivation, Institute of Olive Tree, Subtropical Crops and Viticulture, Hellenic Agricultural Organization DIMITRA, Leoforos Karamanli 167, 73134 Chania, Crete, Greece
| | - Georgios Koubouris
- Laboratory of Olive Cultivation, Institute of Olive Tree, Subtropical Crops and Viticulture, Hellenic Agricultural Organization DIMITRA, Leoforos Karamanli 167, 73134 Chania, Crete, Greece
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Ni J, Li Y, Xiang Y, Yang X, Jia L, Yue J, Wang H. Autophagic degradation of the chloroplastic 2-phosphoglycolate phosphatase TaPGLP1 in wheat. PLANT CELL REPORTS 2022; 41:473-487. [PMID: 34981152 DOI: 10.1007/s00299-021-02820-3] [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: 09/21/2021] [Accepted: 11/23/2021] [Indexed: 06/14/2023]
Abstract
KEY MESSAGE TaPGLP1, a chloroplast stromal 2-phosphoglycolate phosphatase of wheat, is an ATG8-interacting protein and undergoes autophagic degradation in starvation-treated wheat mesophyll protoplasts. Selective autophagy in plants has been shown to target diverse cellular cargoes including whole chloroplasts (Chlorophagy) and several chloroplast components (Piecemeal chlorophagy). Most cargoes of selective autophagy are captured by the autophagic machinery through their direct or indirect interactions with the autophagy-essential factor ATG8. Here, we reported a new ATG8-interacting cargo of piecemeal chlorophagy, the wheat photorespiratory 2-phosphoglycolate phosphatase TaPGLP1. The TaPGLP1-mCherry fusions expressed in wheat protoplasts located in the chloroplast stroma. Strikingly, these fusions are translocated into newly formed chloroplast surface protrusions after a long time incubation of protoplasts in a nutrition-free solution. Visualization of co-expressed TaPGLP1-mCherry and the autophagy marker GFP-TaATG8a revealed physical associations of TaPGLP1-mCherry-accumulating chloroplast protrusions with autophagic structures, implying the delivery of TaPGLP1-mCherry fusions from chloroplasts to the autophagic machinery. TaPGLP1-mCherry fusions were also detected in the GFP-TaATG8a-labelled autophagic bodies undergoing degradation in the vacuoles, which suggested the autophagic degradation of TaPGLP1. This autophagic degradation of TaPGLP1 was further demonstrated by the enhanced stability of TaPGLP1-mCherry in protoplasts with impaired autophagy. Expression of TaPGLP1-mCherry in protoplasts stimulated an enhanced autophagy level probably adopted by cells to degrade the over-produced TaPGLP1-mCherry fusions. Results from gene silencing assays showed the requirement of ATG2s and ATG7s in the autophagic degradation of TaPGLP1. Additionally, TaPGLP1 was shown to interact with ATG8 family members. Collectively, our data suggest that autophagy mediates the degradation of the chloroplast stromal protein TaPGLP1 in starvation-treated mesophyll protoplasts.
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Affiliation(s)
- Jiayao Ni
- College of Life Sciences, Tianjin Key Laboratory of Animal and Plant Resistance, Tianjin Normal University, 393#, BinShuiXi Road, Xiqing, Tianjin, 300387, China
| | - Yuru Li
- College of Life Sciences, Tianjin Key Laboratory of Animal and Plant Resistance, Tianjin Normal University, 393#, BinShuiXi Road, Xiqing, Tianjin, 300387, China
| | - Yue Xiang
- College of Life Sciences, Tianjin Key Laboratory of Animal and Plant Resistance, Tianjin Normal University, 393#, BinShuiXi Road, Xiqing, Tianjin, 300387, China
| | - Xiangyun Yang
- College of Life Sciences, Tianjin Key Laboratory of Animal and Plant Resistance, Tianjin Normal University, 393#, BinShuiXi Road, Xiqing, Tianjin, 300387, China
| | - Lei Jia
- College of Life Sciences, Tianjin Key Laboratory of Animal and Plant Resistance, Tianjin Normal University, 393#, BinShuiXi Road, Xiqing, Tianjin, 300387, China
| | - Jieyu Yue
- College of Life Sciences, Tianjin Key Laboratory of Animal and Plant Resistance, Tianjin Normal University, 393#, BinShuiXi Road, Xiqing, Tianjin, 300387, China
| | - Huazhong Wang
- College of Life Sciences, Tianjin Key Laboratory of Animal and Plant Resistance, Tianjin Normal University, 393#, BinShuiXi Road, Xiqing, Tianjin, 300387, China.
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Ding G, Yang Q, Ruan X, Si T, Yuan B, Zheng W, Xie Q, Souleymane OA, Wang X. Proteomics analysis of the effects for different salt ions in leaves of true halophyte Sesuvium portulacastrum. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2022; 170:234-248. [PMID: 34920320 DOI: 10.1016/j.plaphy.2021.12.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Revised: 12/07/2021] [Accepted: 12/09/2021] [Indexed: 05/25/2023]
Abstract
Sesuvium portulacastrum is a true halophyte and shows an optimal development under moderate salinity with large amounts of salt ions in its leaves. However, the specific proteins in response to salt ions are remained unknown. In this study, comparative physiological and proteomic analyses of different leaves subject to NaCl, KCl, NaNO3 and KNO3 were performed. Chlorophyll content was decreased under the above four kinds of salt treatments. Starch and soluble sugar contents changed differently under different salt treatments. A total of 53 differentially accumulated proteins (DAPs) were identified by mass spectrometry. Among them, 13, 25, 26 and 25 DAPs were identified after exposure to KCl, NaCl, KNO3, and NaNO3, respectively. These DAPs belong to 47 unique genes, and 37 of them are involved in protein-protein interactions. These DAPs displayed different expression patterns after treating with different salt ions. Functional annotation revealed they are mainly involved in photosynthesis, carbohydrate and energy metabolism, lipid metabolism, and biosynthesis of secondary metabolites. Genes and proteins showed different expression profiles under different salt treatments. Enzyme activity analysis indicated P-ATPase was induced by KCl, NaCl and NaNO3, V-ATPase was induced by KCl and NaCl, whereas V-PPase activity was significantly increased after application of KNO3, but sharply inhibited by NaCl. These results might deepen our understanding of responsive mechanisms in the leaves of S. portulacastrum upon different salt ions.
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Affiliation(s)
- Guohua Ding
- College of Life Sciences, Ministry of Education Key Laboratory for Ecology of Tropical Islands, Hainan Normal University, Haikou, Hainan, 571158, China
| | - Qian Yang
- South Subtropical Crop Research Institute, China Academy of Tropical Agricultural Sciences, China
| | - Xueyu Ruan
- College of Life Sciences, Ministry of Education Key Laboratory for Ecology of Tropical Islands, Hainan Normal University, Haikou, Hainan, 571158, China
| | - Tingting Si
- College of Life Sciences, Ministry of Education Key Laboratory for Ecology of Tropical Islands, Hainan Normal University, Haikou, Hainan, 571158, China
| | - Boxuan Yuan
- College of Life Sciences, Ministry of Education Key Laboratory for Ecology of Tropical Islands, Hainan Normal University, Haikou, Hainan, 571158, China; Key Laboratory of Xinjiang Phytomedicine Resource and Utilization of Ministry of Education, College of Life Sciences, Shihezi University, Shihezi, 832003, China
| | - Wenwei Zheng
- College of Life Sciences, Ministry of Education Key Laboratory for Ecology of Tropical Islands, Hainan Normal University, Haikou, Hainan, 571158, China
| | - Quanliang Xie
- Key Laboratory of Xinjiang Phytomedicine Resource and Utilization of Ministry of Education, College of Life Sciences, Shihezi University, Shihezi, 832003, China
| | - Ousmane Ahmat Souleymane
- College of Life Sciences, Ministry of Education Key Laboratory for Ecology of Tropical Islands, Hainan Normal University, Haikou, Hainan, 571158, China
| | - Xuchu Wang
- College of Life Sciences, Ministry of Education Key Laboratory for Ecology of Tropical Islands, Hainan Normal University, Haikou, Hainan, 571158, China.
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Hussain S, Hussain S, Ali B, Ren X, Chen X, Li Q, Saqib M, Ahmad N. Recent progress in understanding salinity tolerance in plants: Story of Na +/K + balance and beyond. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2021; 160:239-256. [PMID: 33524921 DOI: 10.1016/j.plaphy.2021.01.029] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 01/18/2021] [Indexed: 05/07/2023]
Abstract
High salt concentrations in the growing medium can severely affect the growth and development of plants. It is imperative to understand the different components of salt-tolerant network in plants in order to produce the salt-tolerant cultivars. High-affinity potassium transporter- and myelocytomatosis proteins have been shown to play a critical role for salinity tolerance through exclusion of sodium (Na+) ions from sensitive shoot tissues in plants. Numerous genes, that limit the uptake of salts from soil and their transport throughout the plant body, adjust the ionic and osmotic balance of cells in roots and shoots. In the present review, we have tried to provide a comprehensive report of major research advances on different mechanisms regulating plant tolerance to salinity stress at proteomics, metabolomics, genomics and transcriptomics levels. Along with the role of ionic homeostasis, a major focus was given on other salinity tolerance mechanisms in plants including osmoregulation and osmo-protection, cell wall remodeling and integrity, and plant antioxidative defense. Major proteins and genes expressed under salt-stressed conditions and their role in enhancing salinity tolerance in plants are discussed as well. Moreover, this manuscript identifies and highlights the key questions on plant salinity tolerance that remain to be discussed in the future.
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Affiliation(s)
- Sadam Hussain
- College of Agronomy, Northwest A&F University, Yangling, Shaanxi, China; Department of Agronomy, University of Agriculture, Faisalabad, Pakistan
| | - Saddam Hussain
- Department of Agronomy, University of Agriculture, Faisalabad, Pakistan; Shanghai Center for Plant Stress Biology, Chinese Academy of Agricultural Sciences, Shanghai, China.
| | - Basharat Ali
- Department of Agronomy, University of Agriculture, Faisalabad, Pakistan
| | - Xiaolong Ren
- College of Agronomy, Northwest A&F University, Yangling, Shaanxi, China
| | - Xiaoli Chen
- College of Agronomy, Northwest A&F University, Yangling, Shaanxi, China
| | - Qianqian Li
- College of Agronomy, Northwest A&F University, Yangling, Shaanxi, China
| | - Muhammad Saqib
- Agronomic Research Institute, Ayub Agricultural Research Institute, Faisalabad, Pakistan
| | - Naeem Ahmad
- College of Agronomy, Northwest A&F University, Yangling, Shaanxi, China
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7
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Dos Santos Araújo G, de Oliveira Paula-Marinho S, de Paiva Pinheiro SK, de Castro Miguel E, de Sousa Lopes L, Camelo Marques E, de Carvalho HH, Gomes-Filho E. H 2O 2 priming promotes salt tolerance in maize by protecting chloroplasts ultrastructure and primary metabolites modulation. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2021; 303:110774. [PMID: 33487358 DOI: 10.1016/j.plantsci.2020.110774] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 10/19/2020] [Accepted: 11/24/2020] [Indexed: 05/21/2023]
Abstract
Hydrogen peroxide priming has emerged as a powerful strategy to trigger multiple responses involved in plant acclimation that reinforce tolerance to abiotic stresses, including salt stress. Thus, this study aimed to investigate the impact of foliar H2O2 priming on the physiological, biochemical, and ultrastructural traits related to photosynthesis of salt-stressed plants. Besides, we provided comparative leaf metabolomic profiles of Zea mays plants under such conditions. For this, H2O or H2O2 pretreated plants were grown under saline conditions for 12-days. Salinity drastically affected photosynthetic parameters and structural chloroplasts integrity, also increased reactive oxygen species contents promoting disturbance in the plant metabolism when compared to non-saline conditions. Our results suggest that H2O2-pretreated plants improved photosynthetic performance avoiding salinity-induced energy excess and ultrastructural damage by preserving stacking thylakoids. It displayed modulation of some metabolites, as arabitol, glucose, asparagine, and tyrosine, which may contribute to the maintenance of osmotic balance and reduced oxidative stress. Hence, our study brings new insights into an understanding of plant acclimation to salinity by H2O2 priming based on photosynthesis maintenance and metabolite modulation.
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Affiliation(s)
| | | | | | - Emílio de Castro Miguel
- Department of Metallurgical and Materials Engineering and Analytical Center, Federal University of Ceará, Fortaleza, Brazil.
| | | | - Elton Camelo Marques
- Department of Biochemistry and Molecular Biology, Federal University of Ceará, Brazil.
| | | | - Enéas Gomes-Filho
- Department of Biochemistry and Molecular Biology and National Institute of Science and Technology in Salinity (INCTSal/CNPq), Federal University of Ceará, Pici Campus St., 60455-760, Fortaleza, CE, Brazil.
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8
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Hertle AP, Haberl B, Bock R. Horizontal genome transfer by cell-to-cell travel of whole organelles. SCIENCE ADVANCES 2021; 7:7/1/eabd8215. [PMID: 33523859 PMCID: PMC7775762 DOI: 10.1126/sciadv.abd8215] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 11/04/2020] [Indexed: 05/10/2023]
Abstract
Recent work has revealed that both plants and animals transfer genomes between cells. In plants, horizontal transfer of entire plastid, mitochondrial, or nuclear genomes between species generates new combinations of nuclear and organellar genomes, or produces novel species that are allopolyploid. The mechanisms of genome transfer between cells are unknown. Here, we used grafting to identify the mechanisms involved in plastid genome transfer from plant to plant. We show that during proliferation of wound-induced callus, plastids dedifferentiate into small, highly motile, amoeboid organelles. Simultaneously, new intercellular connections emerge by localized cell wall disintegration, forming connective pores through which amoeboid plastids move into neighboring cells. Our work uncovers a pathway of organelle movement from cell to cell and provides a mechanistic framework for horizontal genome transfer.
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Affiliation(s)
- Alexander P Hertle
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
| | - Benedikt Haberl
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
| | - Ralph Bock
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany.
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9
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Cekstere G, Osvalde A, Elferts D, Rose C, Lucas F, Vollenweider P. Salt accumulation and effects within foliage of Tilia × vulgaris trees from the street greenery of Riga, Latvia. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 747:140921. [PMID: 32777490 DOI: 10.1016/j.scitotenv.2020.140921] [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: 03/27/2020] [Revised: 06/12/2020] [Accepted: 07/10/2020] [Indexed: 06/11/2023]
Abstract
Green infrastructures within sprawling cities provide essential ecosystem services, increasingly undermined by environmental stress. The main objective in this study was to relate the allocation patterns of NaCl contaminants to injury within foliage of lime trees mechanistically and distinguish between the effects of salt and other environmental stressors. Using field material representative of salt contamination levels in the street greenery of Riga, Latvia, the contribution of salt contaminants to structural and ultrastructural injury was analyzed, combining different microscopy techniques. On severely salt-polluted and dystrophic soils, the foliage of street lime trees showed foliar concentrations of Na/Cl up to 13,600/16,750 mg kg-1 but a still balanced nutrient content. The salt contaminants were allocated to all leaf blade tissues and accumulated in priority within mesophyll vacuoles, changing the vacuolar ionic composition at the expense of especially K and Ca. The size of mesophyll cells and vacuoles was increased as a function of NaCl concentration, suggesting impeded transpiration stream. In parallel, the cytoplasm showed degenerative changes, suggesting indirect stress effects. Hence, the lime trees in Riga showed tolerance to the dystrophic environmental conditions enhanced by salt pollution but their leaf physiology appeared directly impacted by the accumulation of contaminants within foliage.
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Affiliation(s)
- Gunta Cekstere
- Laboratory of Plant Mineral Nutrition, Institute of Biology, University of Latvia, Miera street 3, Salaspils LV-2169, Latvia; Swiss Federal Research Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, CH-8903 Birmensdorf, Switzerland.
| | - Anita Osvalde
- Laboratory of Plant Mineral Nutrition, Institute of Biology, University of Latvia, Miera street 3, Salaspils LV-2169, Latvia.
| | - Didzis Elferts
- Faculty of Biology, University of Latvia, Jelgavas street 1, Riga LV-1004, Latvia.
| | - Christophe Rose
- Centre INRA, Grand Est Nancy, UMR Silva-Silvatech Microscopy, 54280 Champenoux, France.
| | - Falk Lucas
- Scientific Center for Optical and Electron Microscopy (ScopeM) of the ETH Zurich, Otto-Stern-Weg 3, 8093 Zürich, Switzerland.
| | - Pierre Vollenweider
- Swiss Federal Research Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, CH-8903 Birmensdorf, Switzerland.
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Oi T, Enomoto S, Nakao T, Arai S, Yamane K, Taniguchi M. Three-dimensional ultrastructural change of chloroplasts in rice mesophyll cells responding to salt stress. ANNALS OF BOTANY 2020; 125:833-840. [PMID: 31773147 PMCID: PMC7182591 DOI: 10.1093/aob/mcz192] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 11/26/2019] [Indexed: 05/02/2023]
Abstract
BACKGROUND AND AIMS Excess salinity inhibits the metabolism of various systems and induces structural changes, especially in chloroplasts. Although the chloroplast body seems to swell under salinity stress as observed by conventional transmission electron microscopy, previous studies are limited to 2-D data and lack quantitative comparisons because specimens need to be sliced into ultrathin sections. This study shows three-dimensionally the structural changes in a whole mesophyll cell responding to salinity stress by serial sectioning with a focused ion beam scanning electron microscope (FIB-SEM) and compares the differences in chloroplast structures based on reconstructed models possessing accurate numerical voxel values. METHODS Leaf blades of rice plants treated with 100 mm NaCl or without (control) for 4 d were fixed chemically and embedded in resin. The specimen blocks were sectioned and observed using the FIB-SEM, and then the sliced image stacks were reconstructed into 3-D models by image processing software. KEY RESULTS On the transverse sections of rice mesophyll cells, the chloroplasts in the control leaves appeared to be elongated meniscus lens shaped, while those in the salt-treated leaves appear to be expanded oval shaped. The 3-D models based on serial sectioning images showed that the chloroplasts in the control cells spread like sheets fitted to the shape of the cell wall and in close contact with the adjacent chloroplasts. In contrast, those in the salt-stressed cells curled up into a ball and fitted to cell protuberances without being in close contact with adjacent chloroplasts. Although the shapes of chloroplasts were clearly different between the two treatments, their volumes did not differ. CONCLUSIONS The 3-D reconstructed models of whole rice mesophyll cells indicated that chloroplasts under salt stress conditions were not swollen but became spherical without increasing their volume. This is in contrast to findings of previous studies based on 2-D images.
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Affiliation(s)
- Takao Oi
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
| | - Sakiko Enomoto
- High Voltage Electron Microscope Laboratory, Institute of Materials and Systems for Sustainability, Nagoya University, Nagoya, Japan
| | - Tomoyo Nakao
- High Voltage Electron Microscope Laboratory, Institute of Materials and Systems for Sustainability, Nagoya University, Nagoya, Japan
| | - Shigeo Arai
- High Voltage Electron Microscope Laboratory, Institute of Materials and Systems for Sustainability, Nagoya University, Nagoya, Japan
| | - Koji Yamane
- Graduate School of Agriculture, Kindai University, Nara, Japan
| | - Mitsutaka Taniguchi
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
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11
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Shull TE, Kurepa J, Smalle JA. Anatase TiO 2 Nanoparticles Induce Autophagy and Chloroplast Degradation in Thale Cress ( Arabidopsis thaliana). ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:9522-9532. [PMID: 31356742 DOI: 10.1021/acs.est.9b01648] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The extensive use of TiO2 nanoparticles and their subsequent release into the environment have posed an important question about the effects of this nanomaterial on ecosystems. Here, we analyzed the link between the damaging effects of reactive oxygen species generated by TiO2 nanoparticles and autophagy, a housekeeping mechanism that removes damaged cellular constituents. We show that TiO2 nanoparticles induce autophagy in the plant model system Arabidopsis thaliana and that autophagy is an important mechanism for managing TiO2 nanoparticle-induced oxidative stress. Additionally, we find that TiO2 nanoparticles induce oxidative stress predominantly in chloroplasts and that this chloroplastic stress is mitigated by autophagy. Collectively, our results suggest that photosynthetic organisms are particularly susceptible to TiO2 nanoparticle toxicity.
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Affiliation(s)
- Timothy E Shull
- Department of Plant and Soil Sciences , University of Kentucky , Lexington , Kentucky 40546 United States
| | - Jasmina Kurepa
- Department of Plant and Soil Sciences , University of Kentucky , Lexington , Kentucky 40546 United States
| | - Jan A Smalle
- Department of Plant and Soil Sciences , University of Kentucky , Lexington , Kentucky 40546 United States
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12
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Shrestha A, Song X, Barbour MM. The temperature response of mesophyll conductance, and its component conductances, varies between species and genotypes. PHOTOSYNTHESIS RESEARCH 2019; 141:65-82. [PMID: 30771063 DOI: 10.1007/s11120-019-00622-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Accepted: 01/25/2019] [Indexed: 05/08/2023]
Abstract
The temperature response of mesophyll conductance to CO2 diffusion (gm) has been shown to vary considerably between species but remains poorly understood. Here, we tested the hypothesis that increases in chloroplast surface area with increasing temperature, due to the formation of chloroplast protrusions, caused observed positive responses of gm to temperature. We found no evidence of chloroplast protrusions. Using simultaneous measurements of carbon and oxygen isotope discrimination during photosynthesis to separate total gm (gm13) into cell wall and plasma membrane conductance (gm18) and chloroplast membrane conductance (gcm) components, we explored the temperature response in genotypes of soybean and barley, and sunflower plants grown at differing CO2 concentrations. Differences in the temperature sensitivity of gm18 were found between genotypes and between plants grown at differing CO2 concentration but did not relate to measured anatomical features such as chloroplast surface area or cell wall thickness. The closest fit of modelled gm13 to estimated values was found when cell wall thickness was allowed to decline at higher temperatures and transpiration rates, but it remains to be tested if this decline is realistic. The temperature response of gcm (calculated from the difference between 1/gm13 and 1/gm18) varied between barley genotypes, and was best fitted by an optimal response in sunflower. Taken together, these results indicate that gm is a highly complex trait with unpredictable sensitivity to temperature that varies between species, between genotypes within a single species, with growth environment, between replicate leaves, and even with age for an individual leaf.
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Affiliation(s)
- Arjina Shrestha
- School of Life and Environmental Sciences, The University of Sydney, 380 Werombi Road, Brownlow Hill, NSW, 2570, Australia
| | - Xin Song
- School of Life and Environmental Sciences, The University of Sydney, 380 Werombi Road, Brownlow Hill, NSW, 2570, Australia
- School of Life Sciences and Oceanography, Shenzhen University, 3688 Nanhai Ave, Shenzhen, Guangdong, 518060, China
| | - Margaret M Barbour
- School of Life and Environmental Sciences, The University of Sydney, 380 Werombi Road, Brownlow Hill, NSW, 2570, Australia.
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13
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Machado SR, Gregório EA, Rodrigues TM. Structural associations between organelle membranes in nectary parenchyma cells. PLANTA 2018; 247:1067-1076. [PMID: 29344723 DOI: 10.1007/s00425-018-2844-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 01/07/2018] [Indexed: 06/07/2023]
Abstract
The close association between membranes and organelles, and the intense chloroplast remodeling in parenchyma cells of extrafloral nectaries occurred only at the secretion time and suggest a relationship with the nectar secretion. Associations between membranes and organelles have been well documented in different tissues and cells of plants, but poorly explored in secretory cells. Here, we described the close physical juxtaposition between membranes and organelles, mainly with chloroplasts, in parenchyma cells of Citharexylum myrianthum (Verbenaeceae) extrafloral nectaries under transmission electron microscopy, using conventional and microwave fixation. At the time of nectar secretion, nectary parenchyma cells exhibit a multitude of different organelle and membrane associations as mitochondria-mitochondria, mitochondria-endoplasmic reticulum, mitochondria-chloroplast, chloroplast-nuclear envelope, mitochondria-nuclear envelope, chloroplast-plasmalemma, chloroplast-chloroplast, chloroplast-tonoplast, chloroplast-peroxisome, and mitochondria-peroxisome. These associations were visualized as amorphous electron-dense material, a network of dense fibrillar material and/or dense bridges. Chloroplasts exhibited protrusions variable in shape and extension, which bring them closer to each other and to plasmalemma, tonoplast, and nuclear envelope. Parenchyma cells in the pre- and post-secretory stages did not exhibit any association or juxtaposition of membranes and organelles, and chloroplast protrusions were absent. Chloroplasts had peripheral reticulum that was more developed in the secretory stage. We propose that such subcellular phenomena during the time of nectar secretion optimize the movement of signaling molecules and the exchange of metabolites. Our results open new avenues on the potential mechanisms of organelle contact in parenchyma nectary cells, and reveal new attributes of the secretory cells on the subcellular level.
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Affiliation(s)
- Silvia Rodrigues Machado
- Department of Botany, Institute of Biosciences of Botucatu (IBB), São Paulo State University (UNESP), Botucatu, SP, Brazil.
| | - Elisa A Gregório
- Center of Electron Microscopy (CME), Institute of Biosciences of Botucatu (IBB), São Paulo State University (UNESP), Botucatu, SP, Brazil
| | - Tatiane M Rodrigues
- Department of Botany, Institute of Biosciences of Botucatu (IBB), São Paulo State University (UNESP), Botucatu, SP, Brazil
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14
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Wang X, Wang W, Huang J, Peng S, Xiong D. Diffusional conductance to CO 2 is the key limitation to photosynthesis in salt-stressed leaves of rice (Oryza sativa). PHYSIOLOGIA PLANTARUM 2018; 163:45-58. [PMID: 29055043 DOI: 10.1111/ppl.12653] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 10/02/2017] [Accepted: 10/17/2017] [Indexed: 05/06/2023]
Abstract
Salinity significantly limits leaf photosynthesis but the factors causing the limitation in salt-stressed leaves remain unclear. In the present work, photosynthetic and biochemical traits were investigated in four rice genotypes under two NaCl concentration (0 and 150 mM) to assess the stomatal, mesophyll and biochemical contributions to reduced photosynthetic rate (A) in salt-stressed leaves. Our results indicated that salinity led to a decrease in A, leaf osmotic potential, electron transport rate and CO2 concentrations in the chloroplasts (Cc ) of rice leaves. Decreased A in salt-stressed leaves was mainly attributable to low Cc , which was determined by stomatal and mesophyll conductance. The increased stomatal limitation was mainly related to the low leaf osmotic potential caused by soil salinity. However, the increased mesophyll limitation in salt-stressed leaves was related to both osmotic stress and ion stress. These findings highlight the importance of considering mesophyll conductance when developing salinity-tolerant rice cultivars.
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Affiliation(s)
- Xiaoxiao Wang
- National Key Laboratory of Crop Genetic Improvement, MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Wencheng Wang
- National Key Laboratory of Crop Genetic Improvement, MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Jianliang Huang
- National Key Laboratory of Crop Genetic Improvement, MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Shaobing Peng
- National Key Laboratory of Crop Genetic Improvement, MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Dongliang Xiong
- National Key Laboratory of Crop Genetic Improvement, MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
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15
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Avin-Wittenberg T, Baluška F, Bozhkov PV, Elander PH, Fernie AR, Galili G, Hassan A, Hofius D, Isono E, Le Bars R, Masclaux-Daubresse C, Minina EA, Peled-Zehavi H, Coll NS, Sandalio LM, Satiat-Jeunemaitre B, Sirko A, Testillano PS, Batoko H. Autophagy-related approaches for improving nutrient use efficiency and crop yield protection. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:1335-1353. [PMID: 29474677 DOI: 10.1093/jxb/ery069] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 02/16/2018] [Indexed: 05/18/2023]
Abstract
Autophagy is a eukaryotic catabolic pathway essential for growth and development. In plants, it is activated in response to environmental cues or developmental stimuli. However, in contrast to other eukaryotic systems, we know relatively little regarding the molecular players involved in autophagy and the regulation of this complex pathway. In the framework of the COST (European Cooperation in Science and Technology) action TRANSAUTOPHAGY (2016-2020), we decided to review our current knowledge of autophagy responses in higher plants, with emphasis on knowledge gaps. We also assess here the potential of translating the acquired knowledge to improve crop plant growth and development in a context of growing social and environmental challenges for agriculture in the near future.
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Affiliation(s)
- Tamar Avin-Wittenberg
- Department of Plant and Environmental Sciences, Alexander Silberman Institute of Life Sciences, Hebrew University of Jerusalem, Givat Ram, Jerusalem, Israel
| | - Frantisek Baluška
- Institute of Cellular and Molecular Botany, University of Bonn, Kirschallee, Bonn, Germany
| | - Peter V Bozhkov
- Department of Molecular Sciences, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
| | - Pernilla H Elander
- Department of Molecular Sciences, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
| | - Alisdair R Fernie
- Max-Planck-Institute of Molecular Plant Physiology, Am Mühlenberg, Potsdam-Golm, Germany
| | - Gad Galili
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot Israel
| | - Ammar Hassan
- Institute of Cellular and Molecular Botany, University of Bonn, Kirschallee, Bonn, Germany
| | - Daniel Hofius
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center of Plant Biology, Uppsala, Sweden
| | - Erika Isono
- Department of Biology, University of Konstanz, Universitätsstrasse, Konstanz, Germany
| | - Romain Le Bars
- Cell Biology Pôle Imagerie-Gif, Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Céline Masclaux-Daubresse
- INRA-AgroParisTech, Institut Jean-Pierre Bourgin, UMR1318, ERL CNRS 3559, Saclay Plant Sciences, Versailles, France
| | - Elena A Minina
- Department of Molecular Sciences, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
| | - Hadas Peled-Zehavi
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot Israel
| | - Núria S Coll
- Centre for Research in Agricultural Genomics (CSIC-IRTA-UAB-UB), Bellaterra-Cerdanyola del Valles, Catalonia, Spain
| | - Luisa M Sandalio
- Departmento de Bioquímica, Biología Celular y Molecular de Plantas Experimental del Zaidín, CSIC, Granada, Spain
| | - Béatrice Satiat-Jeunemaitre
- Cell Biology Pôle Imagerie-Gif, Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Agnieszka Sirko
- Institute of Biochemistry and Biophysics Polish Academy of Sciences, ul. Pawinskiego, Warsaw, Poland
| | - Pilar S Testillano
- Pollen Biotechnology of Crop Plants group, Centro de Investigaciones Biológicas, Biological Research Centre (CIB), CSIC, Ramiro de Maeztu, Madrid, Spain
| | - Henri Batoko
- Université Catholique de Louvain, Institute of Life Sciences, Croix du Sud, Louvain-la-Neuve, Belgium
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16
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Yamane K, Oi T, Enomoto S, Nakao T, Arai S, Miyake H, Taniguchi M. Three-dimensional ultrastructure of chloroplast pockets formed under salinity stress. PLANT, CELL & ENVIRONMENT 2018; 41:563-575. [PMID: 29216410 DOI: 10.1111/pce.13115] [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: 06/28/2014] [Revised: 11/21/2017] [Accepted: 11/22/2017] [Indexed: 06/07/2023]
Abstract
We investigated the invagination structure of a chloroplast that surrounds organelles such as mitochondria and peroxisomes within a thin layer of chloroplast stroma, which is called a chloroplast pocket. In this study, chloroplast pockets were observed in rice plants subjected to salinity stress but not under moderate growth condition. They included cytosol, transparent structure, lipid bodies, mitochondria, and peroxisomes. We constructed the three-dimensional architecture of chloroplast pockets by using serial images obtained by transmission electron microscopy and focused ion beam-scanning electron microscopy. Three types of chloroplast pockets were observed by transmission electron microscopy: Organelles were completely enclosed in a chloroplast pocket (enclosed type), a chloroplast pocket with a small gap in the middle part (gap type), and a chloroplast pocket with one side open (open type). Of the 70 pockets observed by serial imaging, 35 were enclosed type, and 21 and 14 were gap and open types, respectively. Mitochondria and peroxisomes were often in contact with the chloroplast pockets. Focused ion beam-scanning electron microscopy revealed chloroplasts with a sheet structure partially surrounding peroxisomes. This fact suggests that chloroplasts might construct large sheet structures that would be related to the formation of chloroplast pockets.
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Affiliation(s)
- Koji Yamane
- Graduate School of Agricultural Sciences, Kindai University, Nara, 631-8505, Japan
| | - Takao Oi
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601, Japan
| | - Sakiko Enomoto
- High Voltage Electron Microscope Laboratory, Institute of Materials and Systems for Sustainability, Nagoya University, Nagoya, 464-8601, Japan
| | - Tomoyo Nakao
- High Voltage Electron Microscope Laboratory, Institute of Materials and Systems for Sustainability, Nagoya University, Nagoya, 464-8601, Japan
| | - Shigeo Arai
- High Voltage Electron Microscope Laboratory, Institute of Materials and Systems for Sustainability, Nagoya University, Nagoya, 464-8601, Japan
| | - Hiroshi Miyake
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601, Japan
| | - Mitsutaka Taniguchi
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601, Japan
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17
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Otegui MS. Vacuolar degradation of chloroplast components: autophagy and beyond. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:741-750. [PMID: 28992297 DOI: 10.1093/jxb/erx234] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 07/10/2017] [Indexed: 05/21/2023]
Abstract
Chloroplast degradation during natural or stress-induced senescence requires the participation of both plastidic and extraplastidic degradative pathways. As part of the extraplastidic pathways, chloroplasts export stroma, envelope, and thylakoid proteins in membrane-bound organelles that are ultimately degraded in vacuoles. Some of these pathways, such as the formation of senescence-associated vacuoles (SAVs) and CV-containing vesicles (CCVs), do not depend on autophagy, whereas delivery of Rubisco-containing bodies (RCBs), ATI1-PS (ATG8-interacting Protein 1) bodies, and small starch-like granule (SSLG) bodies is autophagy dependent. In addition, autophagy of entire chloroplasts delivers damaged chloroplasts into the vacuolar lumen for degradation. This review summarizes the autophagy-dependent and independent trafficking mechanisms by which plant cells degrade chloroplast components in vacuoles.
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Affiliation(s)
- Marisa S Otegui
- Laboratory of Cell and Molecular Biology and Departments of Botany and Genetics, University of Wisconsin-Madison, WI, USA
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18
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Bejaoui F, Salas JJ, Nouairi I, Smaoui A, Abdelly C, Martínez-Force E, Youssef NB. Changes in chloroplast lipid contents and chloroplast ultrastructure in Sulla carnosa and Sulla coronaria leaves under salt stress. JOURNAL OF PLANT PHYSIOLOGY 2016; 198:32-8. [PMID: 27131842 DOI: 10.1016/j.jplph.2016.03.018] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 03/22/2016] [Accepted: 03/23/2016] [Indexed: 05/25/2023]
Abstract
The possible involvement of chloroplast lipids in the mechanisms of NaCl tolerance was studied in leaves of two varieties of Fabaceae: Sulla carnosa and Sulla coronaria, which were subjected to 200mM NaCl over 20days. Changes in membrane lipid peroxidation, chloroplast lipids content, fatty acids (FA) composition and the ultrastructure of chloroplasts under salt stress were investigated. Chloroplast lipids were separated and quantified by high performance liquid chromatography coupled to evaporative light scattering detection (HPLC/ELSD). The results showed that salinity induced a significant decrease in digalactosyldiacylglycerol (DGDG), phosphatidylglycerol (PG) and sulfoquinovosylglycerol (SQDG) content in both S. carnosa and S. coronaria leaves, whereas monogalactosyldiacylglycerol (MGDG) content did not change significantly in S. carnosa leaves. The MGDG/DGDG ratio remained stable in S. coronaria leaves but increased in those of S. carnosa. In addition, the unsaturated-to-saturated fatty acids ratio (UFAs:SFAs) did not change under salt stress in S. coronaria leaves, while it decreased significantly in S. carnosa leaves. Moreover, salinity did not induce significant changes in MGDG and DGDG unsaturation level in S. carnosa leaves, in contrast to S. coronaria, in which salinity seems to enhance the unsaturation level in MGDG, DGDG and PG. Furthermore, the level of membrane lipid peroxidation, as expressed by malondialdehyde (MDA) levels, increased at 200mM in S. carnosa leaves, while it did not change significantly in those of S. coronaria. With respect to the ultrastructure of chloroplasts at 200mM NaCl, investigated by transmission electron microscopy (TEM), salt-stress caused the swelling of thylakoids in S. carnosa mesophyll. These ultrastructural changes were observed especially in the spongy tissue in S. coronaria. Taken together, these findings suggest that the stability of MGDG/DGDG ratio, the unchanged unsaturation level, and increasing unsaturation level in MGDG, DGDG and PG may be effective to some degree in suppressing the ultrastructural damage caused by salinity effects and may contribute to protect the chloroplast membrane integrity against salt stress.
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Affiliation(s)
- Fatma Bejaoui
- Laboratory of Extremophile Plants, Center of Biotechnology of Borj-Cedria (LEP-CBBC), P.O. Box 901, 2050 Hammam-Lif, Tunisia.
| | - Joaquín J Salas
- Instituto de la Grasa (CSIC), Edificio 46, Campus Universitario Pablo de Olavide, Carretera de Utrera, Km. 1, 41013 Sevilla, Spain
| | - Issam Nouairi
- laboratory of legumes, Center of Biotechnology of Borj-Cedria (CBBC), P.O. Box 901, 2050 Hammam-Lif, Tunisia
| | - Abderrazak Smaoui
- Laboratory of Extremophile Plants, Center of Biotechnology of Borj-Cedria (LEP-CBBC), P.O. Box 901, 2050 Hammam-Lif, Tunisia
| | - Chedly Abdelly
- Laboratory of Extremophile Plants, Center of Biotechnology of Borj-Cedria (LEP-CBBC), P.O. Box 901, 2050 Hammam-Lif, Tunisia
| | - Enrique Martínez-Force
- Instituto de la Grasa (CSIC), Edificio 46, Campus Universitario Pablo de Olavide, Carretera de Utrera, Km. 1, 41013 Sevilla, Spain
| | - Nabil Ben Youssef
- Laboratory of olive biotechnology, Center of Biotechnology of Borj-Cedria (CBBC), P.O. Box 901, 2050 Hammam-Lif, Tunisia
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Miyake H. Starch Accumulation in the Bundle Sheaths of C3 Plants: A Possible Pre-Condition for C4 Photosynthesis. PLANT & CELL PHYSIOLOGY 2016; 57:890-6. [PMID: 26936788 DOI: 10.1093/pcp/pcw046] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 02/20/2016] [Indexed: 05/09/2023]
Abstract
C4 plants have evolved >60 times from their C3 ancestors. C4 photosynthesis requires a set of closely co-ordinated anatomical and biochemical characteristics. However, it is now recognized that the evolution of C4 plants requires fewer changes than had ever been considered, because of the genetic, biochemical and anatomical pre-conditions of C3 ancestors that were recruited into C4 photosynthesis. Therefore, the pre-conditions in C3 plants are now being actively investigated to clarify the evolutionary trajectory from C3 to C4 plants and to engineer C4 traits efficiently into C3 crops. In the present mini review, the anatomical characteristics of C3 and C4 plants are briefly reviewed and the importance of the bundle sheath for the evolution of C4 photosynthesis is described. For example, while the bundle sheath of C3 rice plants accumulates large amounts of starch in the developing leaf blade and at the lamina joint of the mature leaf, the starch sheath function is also observed during leaf development in starch accumulator grasses regardless of photosynthetic type. The starch sheath function of C3 plants is therefore also implicated as a possible pre-condition for the evolution of C4 photosynthesis. The phylogenetic relationships between the types of storage carbohydrates and of photosynthesis need to be clarified in the future.
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Affiliation(s)
- Hiroshi Miyake
- Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya, 464-8601 Japan
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20
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Baulina O, Gorelova O, Solovchenko A, Chivkunova O, Semenova L, Selyakh I, Scherbakov P, Burakova O, Lobakova E. Diversity of the nitrogen starvation responses in subarcticDesmodesmussp. (Chlorophyceae) strains isolated from symbioses with invertebrates. FEMS Microbiol Ecol 2016; 92:fiw031. [DOI: 10.1093/femsec/fiw031] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/12/2016] [Indexed: 12/28/2022] Open
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21
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Buchner O, Moser T, Karadar M, Roach T, Kranner I, Holzinger A. Formation of chloroplast protrusions and catalase activity in alpine Ranunculus glacialis under elevated temperature and different CO2/O2 ratios. PROTOPLASMA 2015; 252:1613-9. [PMID: 25701381 PMCID: PMC4628086 DOI: 10.1007/s00709-015-0778-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 02/09/2015] [Indexed: 05/23/2023]
Abstract
Chloroplast protrusions (CPs) have frequently been observed in plants, but their significance to plant metabolism remains largely unknown. We investigated in the alpine plant Ranunculus glacialis L. treated under various CO2 concentrations if CP formation is related to photorespiration, specifically focusing on hydrogen peroxide (H2O2) metabolism. Immediately after exposure to different CO2 concentrations, the formation of CPs in leaf mesophyll cells was assessed and correlated to catalase (CAT) and ascorbate peroxidase (APX) activities. Under natural irradiation, the relative proportion of chloroplasts with protrusions (rCP) was highest (58.7 %) after exposure to low CO2 (38 ppm) and was lowest (3.0 %) at high CO2 (10,000 ppm). The same relationship was found for CAT activity, which decreased from 34.7 nkat mg(-1) DW under low CO2 to 18.4 nkat mg(-1) DW under high CO2, while APX activity did not change significantly. When exposed to natural CO2 concentration (380 ppm) in darkness, CP formation was significantly lower (18.2 %) compared to natural solar irradiation (41.3 %). In summary, CP formation and CAT activity are significantly increased under conditions that favour photorespiration, while in darkness or at high CO2 concentration under light, CP formation is significantly lower, providing evidence for an association between CPs and photorespiration.
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Affiliation(s)
- Othmar Buchner
- Institute of Botany, Functional Plant Biology, University of Innsbruck, Sternwartestrasse 15, 6020, Innsbruck, Austria.
| | - Tim Moser
- Institute of Botany, Functional Plant Biology, University of Innsbruck, Sternwartestrasse 15, 6020, Innsbruck, Austria
| | - Matthias Karadar
- Institute of Botany, Functional Plant Biology, University of Innsbruck, Sternwartestrasse 15, 6020, Innsbruck, Austria
| | - Thomas Roach
- Institute of Botany, Functional Plant Biology, University of Innsbruck, Sternwartestrasse 15, 6020, Innsbruck, Austria
| | - Ilse Kranner
- Institute of Botany, Functional Plant Biology, University of Innsbruck, Sternwartestrasse 15, 6020, Innsbruck, Austria
| | - Andreas Holzinger
- Institute of Botany, Functional Plant Biology, University of Innsbruck, Sternwartestrasse 15, 6020, Innsbruck, Austria
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Fang Y, Lu H, Chen S, Zhu K, Song H, Qian H. Leaf proteome analysis provides insights into the molecular mechanisms of bentazon detoxification in rice. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2015; 125:45-52. [PMID: 26615150 DOI: 10.1016/j.pestbp.2015.06.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 05/18/2015] [Accepted: 06/05/2015] [Indexed: 06/05/2023]
Abstract
Bentazon is a widely used herbicide that selectively removes broad-leaf weeds by competing with plastoquinone for the binding site in the D1 protein and interrupting the PET (photosynthetic electron transfer) chain. However, monocotyledonous plants, such as rice, show strong resistance to bentazon due to CYP81A6 induction, which results in herbicide detoxification. Here, we confirmed that rice was sensitive to bentazon treatment during the initial exposure period, in which bentazon rapidly inhibited photosynthesis efficiency and electron transfer, based on results of chlorophyll fluorescence analysis. In order to gain a comprehensive, pathway-oriented, mechanistic understanding of the effects directly induced by bentazon, we employed 2D-DIGE (two-dimensional difference gel electrophoresis) to analyze the leaf proteome after 8h of bentazon treatment coupled with individual protein identification by MALDI-TOF (Matrix assisted laser desorption/ionization-time of flight) MS/MS. Proteomic analyses revealed that bentazon induced the relative upregulation or downregulation of 30 and 71 proteins (by 1.5-fold or more, p<0.05), respectively. The pathways involved include photosynthesis processes, carbohydrate metabolism, antioxidant systems, and DNA stabilization and protein folding. Protein analysis data revealed that bentazon primarily suppressed photosynthesis processes, and showed inhibitory effects on carbohydrate metabolism and ATP synthesis, whereas several stress response proteins were induced in response to bentazon. Importantly, we identified a 519kD protein containing two histidine kinase-like ATPase domains and a C3HC4 RING type zinc finger domain which may function as a transcript factor to drive expression of detoxification genes such as CYP81A6, leading to bentazon tolerance. This study identifies, for the first time, a candidate transcription factor that could up-regulate CYP81A6 expression, and provides a foundation for further research to advance our knowledge of mechanisms of bentazon resistance in rice.
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Affiliation(s)
- Yingzhi Fang
- Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou 310058, PR China
| | - Haiping Lu
- College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, PR China
| | - Si Chen
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, PR China
| | - Kun Zhu
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, PR China
| | - Hao Song
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, PR China
| | - Haifeng Qian
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, PR China; Xinjiang Key Laboratory of Environmental Pollution and Bioremediation, Chinese Academy of Sciences, Urumqi 830011, PR China.
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23
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Chloroplast protrusions in leaves of Ranunculus glacialis
L. respond significantly to different ambient conditions, but are not related to temperature stress. PLANT, CELL & ENVIRONMENT 2015; 38:1347-56. [PMID: 25393014 PMCID: PMC5098225 DOI: 10.1111/pce.12483] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Revised: 11/06/2014] [Accepted: 11/07/2014] [Indexed: 05/09/2023]
Abstract
The occurrence of chloroplast protrusions (CPs) in leaves of Ranunculus glacialis
L. in response to different environmental conditions was assessed. CPs occur highly dynamically. They do not contain thylakoids and their physiological function is still largely unknown. Controlled in situ sampling showed that CP formation follows a pronounced diurnal rhythm. Between 2 and 27 °C the relative proportion of chloroplasts with CPs (rCP) showed a significant positive correlation to leaf temperature (TL; 0.793, P < 0.01), while irradiation intensity had a minor effect on rCP. In situ shading and controlled laboratory experiments confirmed the significant influence of TL. Under moderate irradiation intensity, an increase of TL up to 25 °C significantly promoted CP formation, while a further increase to 37 °C led to a decrease. Furthermore, rCP values were lower in darkness and under high irradiation intensity. Gas treatment at 2000 ppm CO2/2% O2 led to a significant decrease of rCP, suggesting a possible involvement of photorespiration in CP formation. Our findings demonstrate that in R. glacialis, CPs are neither a rare phenomenon nor a result of heat or light stress; on the contrary, they seem to be most abundant under moderate temperature and non‐stress irradiation conditions. Chloroplast protrusions (CPs) are stroma‐filled areas not containing any thylakoids. They are formed dynamically and the physiological function is still largely unknown. We conducted field and laboratory experiments on the nival plant species Ranunculus glacialisL. and demonstrate that CP formation follows a pronounced diurnal rhythm. CPs are neither a result of heat or light stress but seem to be most abundant under moderate temperature and non‐stress irradiation conditions.
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24
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Chang L, Guo A, Jin X, Yang Q, Wang D, Sun Y, Huang Q, Wang L, Peng C, Wang X. The beta subunit of glyceraldehyde 3-phosphate dehydrogenase is an important factor for maintaining photosynthesis and plant development under salt stress-Based on an integrative analysis of the structural, physiological and proteomic changes in chloroplasts in Thellungiella halophila. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2015; 236:223-38. [PMID: 26025536 DOI: 10.1016/j.plantsci.2015.04.010] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2015] [Revised: 04/13/2015] [Accepted: 04/16/2015] [Indexed: 05/11/2023]
Abstract
Thellungiella halophila, a new model halophyte, can survive under highly saline conditions. We performed comparative proteomics of chloroplasts from plants grown under different saline conditions. Seventy-five salt-responsive proteins were positively identified by mass spectrometry, which represented 43 unique ones. These proteins were categorized into 7 main pathways: light reaction, carbon fixation, energy metabolism, antenna proteins, cell structure, and protein degradation and folding. Saline conditions increased the abundance of proteins involved in photosynthesis, energy metabolism and cell structure. The results indicated that Thellungiella could withstand high salinity by maintaining normal or high photosynthetic capacity, reducing ROS production, as well as enhancing energy usage. Meanwhile, the ultrastructural and physiological data also agree with chloroplast proteomics results. Subsequently, the glyceraldehydes 3-phosphate dehydrogenase beta subunit (GAPB) involved in carbon fixation was selected and its role in salt tolerance was clarified by over-expressing it in Arabidopsis. ThGAPB-overexpressing plants had higher total chlorophyll contents, dry weights, water contents and survival rates than that of wild type plants. These results indicated that ThGAPB might improve plant salt tolerance by maintaining higher recycling rates of ADP and NADP(+) to decrease ROS production, helping to maintain photosynthetic efficiency and plant development under saline conditions.
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Affiliation(s)
- Lili Chang
- College of Agriculture, Hainan University, Haikou city 570228, Hainan, China; Key Laboratory of Biology and Genetic Resources for Tropical Crops, Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou city 571101, Hainan, China
| | - Anping Guo
- College of Agriculture, Hainan University, Haikou city 570228, Hainan, China; Key Laboratory of Biology and Genetic Resources for Tropical Crops, Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou city 571101, Hainan, China
| | - Xiang Jin
- Key Laboratory of Biology and Genetic Resources for Tropical Crops, Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou city 571101, Hainan, China
| | - Qian Yang
- Key Laboratory of Biology and Genetic Resources for Tropical Crops, Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou city 571101, Hainan, China
| | - Dan Wang
- Key Laboratory of Biology and Genetic Resources for Tropical Crops, Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou city 571101, Hainan, China
| | - Yong Sun
- Key Laboratory of Biology and Genetic Resources for Tropical Crops, Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou city 571101, Hainan, China
| | - Qixing Huang
- Key Laboratory of Biology and Genetic Resources for Tropical Crops, Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou city 571101, Hainan, China
| | - Limin Wang
- Key Laboratory of Biology and Genetic Resources for Tropical Crops, Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou city 571101, Hainan, China
| | - Cunzhi Peng
- Key Laboratory of Biology and Genetic Resources for Tropical Crops, Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou city 571101, Hainan, China
| | - Xuchu Wang
- College of Agriculture, Hainan University, Haikou city 570228, Hainan, China; Key Laboratory of Biology and Genetic Resources for Tropical Crops, Institute of Tropical Biosciences and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou city 571101, Hainan, China.
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25
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Szymańska R, Nowicka B, Gabruk M, Glińska S, Michlewska S, Dłużewska J, Sawicka A, Kruk J, Laitinen R. Physiological and antioxidant responses of two accessions of Arabidopsis thaliana in different light and temperature conditions. PHYSIOLOGIA PLANTARUM 2015; 154:194-209. [PMID: 25214438 DOI: 10.1111/ppl.12278] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Revised: 07/28/2014] [Accepted: 07/30/2014] [Indexed: 06/03/2023]
Abstract
During their lifetime, plants need to adapt to a changing environment, including light and temperature. To understand how these factors influence plant growth, we investigated the physiological and antioxidant responses of two Arabidopsis accessions, Shahdara (Sha) from the Shahdara valley (Tajikistan, Central Asia) in a mountainous area and Lovvik-5 (Lov-5) from northern Sweden to different light and temperature conditions. These accessions originate from different latitudes and have different life strategies, both of which are known to be influenced by light and temperature. We showed that both accessions grew better in high-light and at a lower temperature (16°C) than in low light and at 23°C. Interestingly, Sha had a lower chlorophyll content but more efficient non-photochemical quenching than Lov-5. Sha, also showed a higher expression of vitamin E biosynthetic genes. We did not observe any difference in the antioxidant prenyllipid level under these conditions. Our results suggest that the mechanisms that keep the plastoquinone (PQ)-pool in more oxidized state could play a role in the adaptation of these accessions to their local climatic conditions.
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Affiliation(s)
- Renata Szymańska
- Department of Medical Physics and Biophysics, Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, Krakow, 30-059, Poland
| | - Beatrycze Nowicka
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry Biophysics and Biotechnology, Jagiellonian University, Krakow, 30-387, Poland
| | - Michał Gabruk
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry Biophysics and Biotechnology, Jagiellonian University, Krakow, 30-387, Poland
| | - Sława Glińska
- Laboratory of Electron Microscopy, Faculty of Biology and Environmental Protection, University of Lodz, Lodz, 90-237, Poland
| | - Sylwia Michlewska
- Laboratory of Electron Microscopy, Faculty of Biology and Environmental Protection, University of Lodz, Lodz, 90-237, Poland
| | - Jolanta Dłużewska
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry Biophysics and Biotechnology, Jagiellonian University, Krakow, 30-387, Poland
| | - Anna Sawicka
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry Biophysics and Biotechnology, Jagiellonian University, Krakow, 30-387, Poland
| | - Jerzy Kruk
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry Biophysics and Biotechnology, Jagiellonian University, Krakow, 30-387, Poland
| | - Roosa Laitinen
- Max-Planck-Institute of Molecular Plant Physiology, Molecular Mechanisms of Adaptation, Potsdam-Golm, 14476, Germany
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26
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Papini A, van Doorn WG. Crystalloids in apparent autophagic plastids: remnants of plastids or peroxisomes? JOURNAL OF PLANT PHYSIOLOGY 2015; 174:36-40. [PMID: 25462964 DOI: 10.1016/j.jplph.2014.10.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Revised: 10/20/2014] [Accepted: 10/20/2014] [Indexed: 06/04/2023]
Abstract
Plant macroautophagy is carried out by autophagosome-type organelles. Recent evidence suggests that plastids also can carry out macroautophagy. The double membrane at the surface of plastids apparently invaginates, forming an intraplastidial space. This space contains a portion of cytoplasm that apparently becomes degraded. Here we report, in Tillandsia sp. and Aechmaea sp., the presence of almost square or diamond-shaped crystalloids inside what seems the intraplastidial space of autophagous plastids. The same type of crystalloids were observed in chloroplasts and other plastids, but were not found in the cytoplasm or the vacuole. Peroxisomes contained smaller and more irregularly shaped crystalloids compared to the ones observed in 'autophagous' plastids. It is hypothesized that plastids are able to sequester chloroplasts and other plastids.
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Affiliation(s)
- Alessio Papini
- Dipartimento di Biologia Vegetale, Università di Firenze, Via La Pira 4, 50132 Florence, Italy.
| | - Wouter G van Doorn
- Mann Laboratory, Department of Plant Sciences, University of California, Davis, CA 95616, USA.
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27
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Delfosse K, Wozny MR, Jaipargas EA, Barton KA, Anderson C, Mathur J. Fluorescent Protein Aided Insights on Plastids and their Extensions: A Critical Appraisal. FRONTIERS IN PLANT SCIENCE 2015; 6:1253. [PMID: 26834765 PMCID: PMC4719081 DOI: 10.3389/fpls.2015.01253] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2015] [Accepted: 12/21/2015] [Indexed: 05/20/2023]
Abstract
Multi-colored fluorescent proteins targeted to plastids have provided new insights on the dynamic behavior of these organelles and their interactions with other cytoplasmic components and compartments. Sub-plastidic components such as thylakoids, stroma, the inner and outer membranes of the plastid envelope, nucleoids, plastoglobuli, and starch grains have been efficiently highlighted in living plant cells. In addition, stroma filled membrane extensions called stromules have drawn attention to the dynamic nature of the plastid and its interactions with the rest of the cell. Use of dual and triple fluorescent protein combinations has begun to reveal plastid interactions with mitochondria, the nucleus, the endoplasmic reticulum and F-actin and suggests integral roles of plastids in retrograde signaling, cell to cell communication as well as plant-pathogen interactions. While the rapid advances and insights achieved through fluorescent protein based research on plastids are commendable it is necessary to endorse meaningful observations but subject others to closer scrutiny. Here, in order to develop a better and more comprehensive understanding of plastids and their extensions we provide a critical appraisal of recent information that has been acquired using targeted fluorescent protein probes.
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28
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Bobik K, Burch-Smith TM. Chloroplast signaling within, between and beyond cells. FRONTIERS IN PLANT SCIENCE 2015; 6:781. [PMID: 26500659 PMCID: PMC4593955 DOI: 10.3389/fpls.2015.00781] [Citation(s) in RCA: 129] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 09/10/2015] [Indexed: 05/18/2023]
Abstract
The most conspicuous function of plastids is the oxygenic photosynthesis of chloroplasts, yet plastids are super-factories that produce a plethora of compounds that are indispensable for proper plant physiology and development. Given their origins as free-living prokaryotes, it is not surprising that plastids possess their own genomes whose expression is essential to plastid function. This semi-autonomous character of plastids requires the existence of sophisticated regulatory mechanisms that provide reliable communication between them and other cellular compartments. Such intracellular signaling is necessary for coordinating whole-cell responses to constantly varying environmental cues and cellular metabolic needs. This is achieved by plastids acting as receivers and transmitters of specific signals that coordinate expression of the nuclear and plastid genomes according to particular needs. In this review we will consider the so-called retrograde signaling occurring between plastids and nuclei, and between plastids and other organelles. Another important role of the plastid we will discuss is the involvement of plastid signaling in biotic and abiotic stress that, in addition to influencing retrograde signaling, has direct effects on several cellular compartments including the cell wall. We will also review recent evidence pointing to an intriguing function of chloroplasts in regulating intercellular symplasmic transport. Finally, we consider an intriguing yet less widely known aspect of plant biology, chloroplast signaling from the perspective of the entire plant. Thus, accumulating evidence highlights that chloroplasts, with their complex signaling pathways, provide a mechanism for exquisite regulation of plant development, metabolism and responses to the environment. As chloroplast processes are targeted for engineering for improved productivity the effect of such modifications on chloroplast signaling will have to be carefully considered in order to avoid unintended consequences on plant growth and development.
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Affiliation(s)
| | - Tessa M. Burch-Smith
- *Correspondence: Tessa M. Burch-Smith, Department of Biochemistry, Cellular and Molecular Biology, University of Tennessee, 1414 Cumberland Avenue, M407 Walters Life Science, Knoxville, TN 37932, USA,
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29
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van Doorn WG, Prisa D. Lipid globules on the plastid surface in Iris tepal epidermis cells during tepal maturation and senescence. JOURNAL OF PLANT PHYSIOLOGY 2014; 171:1714-1721. [PMID: 25213705 DOI: 10.1016/j.jplph.2014.08.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Revised: 08/08/2014] [Accepted: 08/08/2014] [Indexed: 06/03/2023]
Abstract
Epidermis cells in the outer tepals of Iris flowers (Iris×hollandica, cv. Blue Magic) start programmed cell death (PCD) prior to floral opening. The tepals show visible senescence symptoms three days after full opening. Visible senescence coincides with collapse (death) of the upper epidermis cells. In these cells, electron-dense particles (plastoglobuli), membranes, and oil bodies were observed in the plastid interior. Electron-dense globules similar to plastoglobuli, thus apparently mainly consisting of lipids, were found on the plastid surface, from before flower opening until cell death. Such electron-dense globules were also present in the cytosol. The size of some of the globules on the plastid surface increased with time. The globules are likely involved in transfer of lipidic/proteinaceous material from the plastid to the cytosol. As the plastids contained ample oil bodies, up to the time of cell death, cell death was likely not due to lack of reserves. Mitochondrial ultrastructure also remained the same until cell death. The role of mitochondria in PCD is discussed.
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Affiliation(s)
- Wouter G van Doorn
- Mann Laboratory, Department of Plant Sciences, University of California, Davis, CA 95616, USA.
| | - Domenico Prisa
- Consiglio per la Ricerca e la Sperimentazione in Agricoltura (CRA-VIV), Via dei Fiori 8, 51012 Pescia, Italy
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30
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Shu S, Chen L, Lu W, Sun J, Guo S, Yuan Y, Li J. Effects of exogenous spermidine on photosynthetic capacity and expression of Calvin cycle genes in salt-stressed cucumber seedlings. JOURNAL OF PLANT RESEARCH 2014; 127:763-73. [PMID: 25069716 DOI: 10.1007/s10265-014-0653-z] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 06/18/2014] [Indexed: 05/16/2023]
Abstract
We investigated the effects of exogenous spermidine (Spd) on growth, photosynthesis and expression of the Calvin cycle-related genes in cucumber seedlings (Cucumis sativus L.) exposed to NaCl stress. Salt stress reduced net photosynthetic rates (PN), actual photochemical efficiency of PSII (ΦPSII) and inhibited plant growth. Application of exogenous Spd to salinized nutrient solution alleviated salinity-induced the inhibition of plant growth, together with an increase in PN and ΦPSII. Salinity markedly reduced the maximum carboxylase activity of ribulose-1,5-bisphosphate carboxylase/oxygenase (Vcmax), the maximal velocity of RuBP regeneration (Jmax), triose-phosphate utilization capacity (TPU) and carboxylation efficiency (CE). Spd alleviated the negative effects on CO2 assimilation induced by salt stress. Moreover, Spd significantly increased the activities and contents of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) and fructose-1,6-biphosphate aldolase (ALD; aldolase) in the salt-stressed cucumber leaves. On the other hand, salinity up-regulated the transcriptional levels of ribulose-1,5-bisphosphate (RCA), glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and phosphoribrokinase (PRK) and down-regulated the transcriptional levels of ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit (RbcL), ribulose-1,5-bisphosphate carboxylase/oxygenase small subunit (RbcS), ALD, triose-3-phosphate isomerase (TPI), fructose-1,6-bisphosphate phosphatase (FBPase) and 3-phosphoglyceric acid kinase (PGK). However, Spd application to salt-stressed plant roots counteracted salinity-induced mRNA expression changes in most of the above-mentioned genes. These results suggest that Spd could improve photosynthetic capacity through regulating gene expression and activity of key enzymes for CO2 fixation, thus confers tolerance to salinity on cucumber plants.
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Affiliation(s)
- Sheng Shu
- College of Horticulture, Nanjing Agricultural University, Key Laboratory of Southern Vegetable Crop Genetic Improvement, Ministry of Agriculture, Weigang No.1, Nanjing, 210095, Jiangsu, People's Republic of China,
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Michaeli S, Honig A, Levanony H, Peled-Zehavi H, Galili G. Arabidopsis ATG8-INTERACTING PROTEIN1 is involved in autophagy-dependent vesicular trafficking of plastid proteins to the vacuole. THE PLANT CELL 2014; 26:4084-101. [PMID: 25281689 PMCID: PMC4247578 DOI: 10.1105/tpc.114.129999] [Citation(s) in RCA: 140] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 08/28/2014] [Accepted: 09/18/2014] [Indexed: 05/18/2023]
Abstract
Selective autophagy has been extensively studied in various organisms, but knowledge regarding its functions in plants, particularly in organelle turnover, is limited. We have recently discovered ATG8-INTERACTING PROTEIN1 (ATI1) from Arabidopsis thaliana and showed that following carbon starvation it is localized on endoplasmic reticulum (ER)-associated bodies that are subsequently transported to the vacuole. Here, we show that following carbon starvation ATI1 is also located on bodies associating with plastids, which are distinct from the ER ATI bodies and are detected mainly in senescing cells that exhibit plastid degradation. Additionally, these plastid-localized bodies contain a stroma protein marker as cargo and were observed budding and detaching from plastids. ATI1 interacts with plastid-localized proteins and was further shown to be required for the turnover of one of them, as a representative. ATI1 on the plastid bodies also interacts with ATG8f, which apparently leads to the targeting of the plastid bodies to the vacuole by a process that requires functional autophagy. Finally, we show that ATI1 is involved in Arabidopsis salt stress tolerance. Taken together, our results implicate ATI1 in autophagic plastid-to-vacuole trafficking through its ability to interact with both plastid proteins and ATG8 of the core autophagy machinery.
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Affiliation(s)
- Simon Michaeli
- Department of Plant Science, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Arik Honig
- Department of Plant Science, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Hanna Levanony
- Department of Plant Science, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Hadas Peled-Zehavi
- Department of Plant Science, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Gad Galili
- Department of Plant Science, The Weizmann Institute of Science, Rehovot 76100, Israel
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Liu CW, Chang TS, Hsu YK, Wang AZ, Yen HC, Wu YP, Wang CS, Lai CC. Comparative proteomic analysis of early salt stress responsive proteins in roots and leaves of rice. Proteomics 2014; 14:1759-75. [PMID: 24841874 DOI: 10.1002/pmic.201300276] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Revised: 04/01/2014] [Accepted: 05/15/2014] [Indexed: 11/11/2022]
Abstract
Growth and productivity of rice (Oryza sativa L.) are severely affected by salinity. Understanding the mechanisms that protect rice and other important cereal crops from salt stress will help in the development of salt-stress-tolerant strains. In this study, rice seedlings of the same genetic species with various salt tolerances were studied. We first used 2DE to resolve the expressed proteome in rice roots and leaves and then used nanospray liquid chromatography/tandem mass spectrometry to identify the differentially expressed proteins in rice seedlings after salt treatment. The 2DE assays revealed that there were 104 differentially expressed protein spots in rice roots and 59 in leaves. Then, we identified 83 proteins in rice roots and 61 proteins in rice leaves by MS analysis. Functional classification analysis revealed that the differentially expressed proteins from roots could be classified into 18 functional categories while those from leaves could be classified into 11 functional categories. The proteins from rice seedlings that most significantly contributed to a protective effect against increased salinity were cysteine synthase, adenosine triphosphate synthase, quercetin 3-O-methyltransferase 1, and lipoxygenase 2. Further analysis demonstrated that the primary mechanisms underlying the ability of rice seedlings to tolerate salt stress were glycolysis, purine metabolism, and photosynthesis. Thus, we suggest that differentially expressed proteins may serve as marker group for the salt tolerance of rice.
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Affiliation(s)
- Chih-Wei Liu
- Institute of Molecular Biology, National Chung Hsing University, Taichung, Taiwan
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Degradation of organelles or specific organelle components via selective autophagy in plant cells. Int J Mol Sci 2014; 15:7624-38. [PMID: 24802874 PMCID: PMC4057695 DOI: 10.3390/ijms15057624] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2014] [Revised: 03/31/2014] [Accepted: 04/16/2014] [Indexed: 12/13/2022] Open
Abstract
Macroautophagy (hereafter referred to as autophagy) is a cellular mechanism dedicated to the degradation and recycling of unnecessary cytosolic components by their removal to the lytic compartment of the cell (the vacuole in plants). Autophagy is generally induced by stresses causing energy deprivation and its operation occurs by special vesicles, termed autophagosomes. Autophagy also operates in a selective manner, recycling specific components, such as organelles, protein aggregates or even specific proteins, and selective autophagy is implicated in both cellular housekeeping and response to stresses. In plants, selective autophagy has recently been shown to degrade mitochondria, plastids and peroxisomes, or organelle components such as the endoplasmic-reticulum (ER) membrane and chloroplast-derived proteins such as Rubisco. This ability places selective-autophagy as a major factor in cellular steady-state maintenance, both under stress and favorable environmental conditions. Here we review the recent advances documented in plants for this cellular process and further discuss its impact on plant physiology.
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He Y, Yu C, Zhou L, Chen Y, Liu A, Jin J, Hong J, Qi Y, Jiang D. Rubisco decrease is involved in chloroplast protrusion and Rubisco-containing body formation in soybean (Glycine max.) under salt stress. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2014; 74:118-24. [PMID: 24291158 DOI: 10.1016/j.plaphy.2013.11.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Accepted: 11/04/2013] [Indexed: 05/09/2023]
Abstract
Salt stress often induces declination of net photosynthetic rate (Pn), partially resulted from Rubisco degradation. The chloroplast protrusions (CPs) is one of the pathways of Rubisco exclusion from chloroplasts. To explore the relationship between the Rubisco contents and CPs under salt stress, Pn, maximum photochemical efficiency of PSII (F(v)/F(m)), carboxylation efficiency (CE) and concentration of Rubisco, number of CPs and Rubisco-containing Body (RCBs) were investigated with two differently salt-responding varieties in this experiment. We observed that 150 mM salt treatment resulted in not only significant decrease in Pn, CE and Rubisco content, but also obvious increase in the number of CPs and RCBs in salt-sensitive variety. Under salt stress formation of CPs resulted in production of much more RCBs, which could immigrate into and combine with vacuole. It may be a kind of important mechanism for rapid degradation of Rubisco under salt stress. Our conclusion provides a new sight for how Rubisco can be fast degraded under salt stress.
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Affiliation(s)
- Yi He
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China; Department of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, United Kingdom
| | - Chenliang Yu
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Li Zhou
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yue Chen
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Ao Liu
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Junhua Jin
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Jian Hong
- Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Yanhua Qi
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Dean Jiang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
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Ishida H, Izumi M, Wada S, Makino A. Roles of autophagy in chloroplast recycling. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2013; 1837:512-21. [PMID: 24269172 DOI: 10.1016/j.bbabio.2013.11.009] [Citation(s) in RCA: 95] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Revised: 11/01/2013] [Accepted: 11/07/2013] [Indexed: 01/04/2023]
Abstract
Chloroplasts are the primary energy suppliers for plants, and much of the total leaf nitrogen is distributed to these organelles. During growth and reproduction, chloroplasts in turn represent a major source of nitrogen to be recovered from senescing leaves and used in newly-forming and storage organs. Chloroplast proteins also can be an alternative substrate for respiration under suboptimal conditions. Autophagy is a process of bulk degradation and nutrient sequestration that is conserved in all eukaryotes. Autophagy can selectively target chloroplasts as whole organelles and or as Rubisco-containing bodies that are enclosed by the envelope and specifically contain the stromal portion of the chloroplast. Although information is still limited, recent work indicates that chloroplast recycling via autophagy plays important roles not only in developmental processes but also in organelle quality control and adaptation to changing environments. This article is part of a Special Issue entitled: Dynamic and ultrastructure of bioenergetic membranes and their components.
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Affiliation(s)
- Hiroyuki Ishida
- Graduate School of Agricultural Sciences, Tohoku University, Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan.
| | - Masanori Izumi
- Department of Environmental Life Sciences, Graduate School of Life Sciences, Tohoku University, Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Shinya Wada
- Graduate School of Agricultural Sciences, Tohoku University, Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan
| | - Amane Makino
- Graduate School of Agricultural Sciences, Tohoku University, Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan; Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency, Chiyoda-ku, Tokyo 102-0076, Japan
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Lee TA, Vande Wetering SW, Brusslan JA. Stromal protein degradation is incomplete in Arabidopsis thaliana autophagy mutants undergoing natural senescence. BMC Res Notes 2013; 6:17. [PMID: 23327451 PMCID: PMC3724497 DOI: 10.1186/1756-0500-6-17] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Accepted: 01/15/2013] [Indexed: 02/08/2023] Open
Abstract
Background Degradation of highly abundant stromal proteins plays an important role in the nitrogen economy of the plant during senescence. Lines of evidence supporting proteolysis within the chloroplast and outside the chloroplast have been reported. Two extra-plastidic degradation pathways, chlorophagy and Rubisco Containing Bodies, rely on cytoplasmic autophagy. Results In this work, levels of three stromal proteins (Rubisco large subunit, chloroplast glutamine synthetase and Rubisco activase) and one thylakoid protein (the major light harvesting complex protein of photosystem II) were measured during natural senescence in WT and in two autophagy T-DNA insertion mutants (atg5 and atg7). Thylakoid-localized protein decreased similarly in all genotypes, but stromal protein degradation was incomplete in the two atg mutants. In addition, degradation of two stromal proteins was observed in chloroplasts isolated from mid-senescence leaves. Conclusions These data suggest that autophagy does contribute to the complete proteolysis of stromal proteins, but does not play a major degenerative role. In addition, support for in organello degradation is provided.
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Affiliation(s)
- Travis A Lee
- Department of Biological Sciences, California State University, Long Beach, 1250 Bellflower Boulevard, Long Beach, CA 90840-9502, USA
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