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Fu Q, Chen T, Wang Y, Zhou H, Zhang K, Zheng R, Zhang Y, Liu R, Yin X, Liu G, Xu Y. Plasmopara viticola effector PvCRN20 represses the import of VvDEG5 into chloroplasts to suppress immunity in grapevine. THE NEW PHYTOLOGIST 2024; 243:2311-2331. [PMID: 39091140 DOI: 10.1111/nph.20002] [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: 02/08/2024] [Accepted: 07/03/2024] [Indexed: 08/04/2024]
Abstract
Chloroplasts play a crucial role in plant defense against pathogens, making them primary targets for pathogen effectors that suppress host immunity. This study characterizes the Plasmopara viticola CRN-like effector, PvCRN20, which interacts with DEG5 in the cytoplasm but not with its interacting protein, DEG8, which is located in the chloroplast. By transiently overexpressing in tobacco leaves, we show that PvCRN20 could inhibit INF1- and Bax-triggered cell death. Constitutive expression of PvCRN20 suppresses the accumulation of reactive oxygen species (ROS) and promotes pathogen colonization. PvCRN20 reduces DEG5 entry into chloroplasts, thereby disrupting DEG5 and DEG8 interactions in chloroplasts. Overexpression of VvDEG5 and VvDEG8 induces ROS accumulation and enhances grapevine resistance to P. viticola, whereas knockout of VvDEG8 represses ROS production and promotes P. viticola colonization. Consistently, ectopic expression of VvDEG5 and VvDEG8 in tobacco promotes chloroplast-derived ROS accumulation, whereas co-expression of PvCRN20 counteracted this promotion by VvDEG5. Therefore, DEG5 is essential for the virulence function of PvCRN20. Although PvCRN20 is located in both the nucleus and cytoplasm, only cytoplasmic PvCRN20 suppresses plant immunity and promotes pathogen infection. Our results reveal that PvCRN20 dampens plant defenses by repressing the chloroplast import of DEG5, thus reducing host ROS accumulation and facilitating pathogen colonization.
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Affiliation(s)
- Qingqing Fu
- State Key Laboratory of Crop Stress Resistance and High-Efficiency Production, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, 712100, China
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Tingting Chen
- College of Agricultural Science, Xichang University, Xichang, 615000, China
| | - Yunlei Wang
- State Key Laboratory of Crop Stress Resistance and High-Efficiency Production, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, 712100, China
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Huixuan Zhou
- State Key Laboratory of Crop Stress Resistance and High-Efficiency Production, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, 712100, China
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Kangzhuang Zhang
- State Key Laboratory of Crop Stress Resistance and High-Efficiency Production, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, 712100, China
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Runlong Zheng
- State Key Laboratory of Crop Stress Resistance and High-Efficiency Production, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, 712100, China
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Yanan Zhang
- State Key Laboratory of Crop Stress Resistance and High-Efficiency Production, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, 712100, China
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Ruiqi Liu
- State Key Laboratory of Crop Stress Resistance and High-Efficiency Production, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, 712100, China
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Xiao Yin
- State Key Laboratory of Crop Stress Resistance and High-Efficiency Production, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, 712100, China
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Guotian Liu
- State Key Laboratory of Crop Stress Resistance and High-Efficiency Production, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, 712100, China
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Yan Xu
- State Key Laboratory of Crop Stress Resistance and High-Efficiency Production, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, 712100, China
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, 712100, China
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Abasi F, Raja NI, Mashwani ZUR, Ehsan M, Ali H, Shahbaz M. Heat and Wheat: Adaptation strategies with respect to heat shock proteins and antioxidant potential; an era of climate change. Int J Biol Macromol 2024; 256:128379. [PMID: 38000583 DOI: 10.1016/j.ijbiomac.2023.128379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 11/21/2023] [Accepted: 11/21/2023] [Indexed: 11/26/2023]
Abstract
Extreme changes in weather including heat-wave and high-temperature fluctuations are predicted to increase in intensity and duration due to climate change. Wheat being a major staple crop is under severe threat of heat stress especially during the grain-filling stage. Widespread food insecurity underscores the critical need to comprehend crop responses to forthcoming climatic shifts, pivotal for devising adaptive strategies ensuring sustainable crop productivity. This review addresses insights concerning antioxidant, physiological, molecular impacts, tolerance mechanisms, and nanotechnology-based strategies and how wheat copes with heat stress at the reproductive stage. In this study stress resilience strategies were documented for sustainable grain production under heat stress at reproductive stage. Additionally, the mechanisms of heat resilience including gene expression, nanomaterials that trigger transcription factors, (HSPs) during stress, and physiological and antioxidant traits were explored. The most reliable method to improve plant resilience to heat stress must include nano-biotechnology-based strategies, such as the adoption of nano-fertilizers in climate-smart practices and the use of advanced molecular approaches. Notably, the novel resistance genes through advanced molecular approach and nanomaterials exhibit promise for incorporation into wheat cultivars, conferring resilience against imminent adverse environmental conditions. This review will help scientific communities in thermo-tolerance wheat cultivars and new emerging strategies to mitigate the deleterious impact of heat stress.
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Affiliation(s)
- Fozia Abasi
- Department of Botany, PMAS-Arid Agriculture University, Rawalpindi 46300, Pakistan.
| | - Naveed Iqbal Raja
- Department of Botany, PMAS-Arid Agriculture University, Rawalpindi 46300, Pakistan.
| | | | - Maria Ehsan
- Department of Botany, PMAS-Arid Agriculture University, Rawalpindi 46300, Pakistan
| | - Habib Ali
- Department of Agronomy, PMAS-Arid Agriculture University, Rawalpindi 46300, Pakistan
| | - Muhammad Shahbaz
- Institute for Tropical Biology and Conservation (ITBC), Universiti Malaysia Sabah, 88400 Kota Kinabalu, Malaysia
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3
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Yang X, Guan H, Yang Y, Zhang Y, Su W, Song S, Liu H, Chen R, Hao Y. Extra- and intranuclear heat perception and triggering mechanisms in plants. FRONTIERS IN PLANT SCIENCE 2023; 14:1276649. [PMID: 37860244 PMCID: PMC10582638 DOI: 10.3389/fpls.2023.1276649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/12/2023] [Accepted: 09/20/2023] [Indexed: 10/21/2023]
Abstract
The escalating impact of global warming on crop yield and quality poses a significant threat to future food supplies. Breeding heat-resistant crop varieties holds promise, but necessitates a deeper understanding of the molecular mechanisms underlying plant heat tolerance. Recent studies have shed light on the initial events of heat perception in plants. In this review, we provide a comprehensive summary of the recent progress made in unraveling the mechanisms of heat perception and response in plants. Calcium ion (Ca2+), hydrogen peroxide (H2O2), and nitric oxide (NO) have emerged as key participants in heat perception. Furthermore, we discuss the potential roles of the NAC transcription factor NTL3, thermo-tolerance 3.1 (TT3.1), and Target of temperature 3 (TOT3) as thermosensors associated with the plasma membrane. Additionally, we explore the involvement of cytoplasmic HISTONE DEACETYLASE 9 (HDA9), mRNA encoding the phytochrome-interacting factor 7 (PIF7), and chloroplasts in mediating heat perception. This review also highlights the role of intranuclear transcriptional condensates formed by phytochrome B (phyB), EARLY FLOWERING 3 (ELF3), and guanylate-binding protein (GBP)-like GTPase 3 (GBPL3) in heat perception. Finally, we raise the unresolved questions in the field of heat perception that require further investigation in the future.
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Affiliation(s)
| | | | | | | | | | | | | | - Riyuan Chen
- College of Horticulture, South China Agricultural University, Guangzhou, China
| | - Yanwei Hao
- College of Horticulture, South China Agricultural University, Guangzhou, China
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Hipsch M, Michael Y, Lampl N, Sapir O, Cohen Y, Helman D, Rosenwasser S. Early detection of late blight in potato by whole-plant redox imaging. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2023; 113:649-664. [PMID: 36534114 DOI: 10.1111/tpj.16071] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Revised: 12/06/2022] [Accepted: 12/12/2022] [Indexed: 06/17/2023]
Abstract
Late blight caused by the oomycete Phytophthora infestans is a most devastating disease of potatoes (Solanum tuberosum). Its early detection is crucial for suppressing disease spread. Necrotic lesions are normally seen in leaves at 4 days post-inoculation (dpi) when colonized cells are dead, but early detection of the initial biotrophic growth stage, when the pathogen feeds on living cells, is challenging. Here, the biotrophic growth phase of P. infestans was detected by whole-plant redox imaging of potato plants expressing chloroplast-targeted reduction-oxidation sensitive green fluorescent protein (chl-roGFP2). Clear spots on potato leaves with a lower chl-roGFP2 oxidation state were detected as early as 2 dpi, before any visual symptoms were recorded. These spots were particularly evident during light-to-dark transitions, and reflected the mislocalization of chl-roGFP2 outside the chloroplasts. Image analysis based on machine learning enabled systematic identification and quantification of spots, and unbiased classification of infected and uninfected leaves in inoculated plants. Comparing redox with chlorophyll fluorescence imaging showed that infected leaf areas that exhibit mislocalized chl-roGFP2 also showed reduced non-photochemical quenching and enhanced quantum PSII yield (ΦPSII) compared with the surrounding leaf areas. The data suggest that mislocalization of chloroplast-targeted proteins is an efficient marker of late blight infection, and demonstrate how it can be utilized for non-destructive monitoring of the disease biotrophic stage using whole-plant redox imaging.
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Affiliation(s)
- Matanel Hipsch
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Rehovot, 7610000, Israel
| | - Yaron Michael
- Department of Soil & Water Sciences, Institute of Environmental Sciences, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 7610001, Israel
| | - Nardy Lampl
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Rehovot, 7610000, Israel
| | - Omer Sapir
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Rehovot, 7610000, Israel
| | - Yigal Cohen
- Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, 5290000, Israel
| | - David Helman
- Department of Soil & Water Sciences, Institute of Environmental Sciences, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 7610001, Israel
- The Advanced School for Environmental Studies, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Shilo Rosenwasser
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Rehovot, 7610000, Israel
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Bajsa-Hirschel J, Pan Z, Pandey P, Asolkar RN, Chittiboyina AG, Boddy L, Machingura MC, Duke SO. Spliceostatin C, a component of a microbial bioherbicide, is a potent phytotoxin that inhibits the spliceosome. FRONTIERS IN PLANT SCIENCE 2023; 13:1019938. [PMID: 36714729 PMCID: PMC9878571 DOI: 10.3389/fpls.2022.1019938] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 11/07/2022] [Indexed: 06/17/2023]
Abstract
Spliceostatin C (SPC) is a component of a bioherbicide isolated from the soil bacterium Burkholderia rinojensis. The chemical structure of SPC closely resembles spliceostatin A (SPA) which was characterized as an anticancer agent and splicing inhibitor. SPC inhibited the growth of Arabidopsis thaliana seedlings with an IC50 value of 2.2 µM. The seedlings exposed to SPC displayed a significant response with decreased root length and number and inhibition of gravitropism. Reverse transcriptase semi-quantitative PCR (RT-sqPCR) analyses of 19 selected genes demonstrated the active impact of SPC on the quality and quantity of transcripts that underwent intron rearrangements as well as up or down expression upon exposure to SPC. Qualitative and quantitative proteomic profiles identified 66 proteins that were significantly affected by SPC treatment. Further proteomics data analysis revealed that spliceostatin C induces hormone-related responses in Arabidopsis seedlings. In silico binding studies showed that SPC binds to a pocket between the SF3B3 and PF5A of the spliceosome.
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Affiliation(s)
- Joanna Bajsa-Hirschel
- Natural Products Utilization Research Unit, Agricultural Research Service, U.S. Department of Agriculture, University, MS, United States
| | - Zhiqiang Pan
- Natural Products Utilization Research Unit, Agricultural Research Service, U.S. Department of Agriculture, University, MS, United States
| | - Pankaj Pandey
- National Center for Natural Products Research, School of Pharmacy, University of Mississippi, University, MS, United States
| | | | - Amar G. Chittiboyina
- National Center for Natural Products Research, School of Pharmacy, University of Mississippi, University, MS, United States
| | - Louis Boddy
- Bioceres Crop Solutions, Davis, CA, United States
| | | | - Stephen O. Duke
- National Center for Natural Products Research, School of Pharmacy, University of Mississippi, University, MS, United States
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6
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Hand KA, Shabek N. The Role of E3 Ubiquitin Ligases in Chloroplast Function. Int J Mol Sci 2022; 23:9613. [PMID: 36077009 PMCID: PMC9455731 DOI: 10.3390/ijms23179613] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 08/23/2022] [Accepted: 08/24/2022] [Indexed: 12/14/2022] Open
Abstract
Chloroplasts are ancient organelles responsible for photosynthesis and various biosynthetic functions essential to most life on Earth. Many of these functions require tightly controlled regulatory processes to maintain homeostasis at the protein level. One such regulatory mechanism is the ubiquitin-proteasome system whose fundamental role is increasingly emerging in chloroplasts. In particular, the role of E3 ubiquitin ligases as determinants in the ubiquitination and degradation of specific intra-chloroplast proteins. Here, we highlight recent advances in understanding the roles of plant E3 ubiquitin ligases SP1, COP1, PUB4, CHIP, and TT3.1 as well as the ubiquitin-dependent segregase CDC48 in chloroplast function.
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Affiliation(s)
| | - Nitzan Shabek
- Department of Plant Biology, College of Biological Sciences, University of California, Davis, CA 95616, USA
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New Insights into the Chloroplast Outer Membrane Proteome and Associated Targeting Pathways. Int J Mol Sci 2022; 23:ijms23031571. [PMID: 35163495 PMCID: PMC8836251 DOI: 10.3390/ijms23031571] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/24/2022] [Accepted: 01/27/2022] [Indexed: 12/04/2022] Open
Abstract
Plastids are a dynamic class of organelle in plant cells that arose from an ancient cyanobacterial endosymbiont. Over the course of evolution, most genes encoding plastid proteins were transferred to the nuclear genome. In parallel, eukaryotic cells evolved a series of targeting pathways and complex proteinaceous machinery at the plastid surface to direct these proteins back to their target organelle. Chloroplasts are the most well-characterized plastids, responsible for photosynthesis and other important metabolic functions. The biogenesis and function of chloroplasts rely heavily on the fidelity of intracellular protein trafficking pathways. Therefore, understanding these pathways and their regulation is essential. Furthermore, the chloroplast outer membrane proteome remains relatively uncharted territory in our understanding of protein targeting. Many key players in the cytosol, receptors at the organelle surface, and insertases that facilitate insertion into the chloroplast outer membrane remain elusive for this group of proteins. In this review, we summarize recent advances in the understanding of well-characterized chloroplast outer membrane protein targeting pathways as well as provide new insights into novel targeting signals and pathways more recently identified using a bioinformatic approach. As a result of our analyses, we expand the known number of chloroplast outer membrane proteins from 117 to 138.
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8
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Osorio Zambrano MA, Castillo DA, Rodríguez Pérez L, Terán W. Cacao ( Theobroma cacao L.) Response to Water Stress: Physiological Characterization and Antioxidant Gene Expression Profiling in Commercial Clones. FRONTIERS IN PLANT SCIENCE 2021; 12:700855. [PMID: 34552605 PMCID: PMC8450537 DOI: 10.3389/fpls.2021.700855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 08/16/2021] [Indexed: 06/13/2023]
Abstract
The increase in events associated with drought constraints plant growth and crop performance. Cacao (Theobroma cacao L.) is sensitive to water deficit stress (DS), which limits productivity. The aim of this research was to characterise the response of seven (CCN51, FEAR5, ICS1, ICS60, ICS95, EET8, and TSH565) commercially important cacao clones to severe and temporal water deficit stress. Ten-month-old cacao trees were submitted to two treatments: well-watered and water-stressed until the leaf water potential (Ψ leaf) reached values between -3.0 and -3.5 MPa. The effects of hydric stress on water relations, gas exchange, photochemical activity, membrane integrity and oxidative stress-related gene expression were evaluated. All clones showed decreases in Ψ leaf, but TSH565 had a higher capacity to maintain water homeostasis in leaves. An initial response phase consisted of stomatal closure, a general mechanism to limit water loss: as a consequence, the photosynthetic rate dropped by approximately 98% on average. In some clones, the photosynthetic rate reached negative values at the maximum stress level, evidencing photorespiration and was confirmed by increased intracellular CO2. A second and photosynthetically limited phase was characterized by a drop in PSII quantum efficiency, which affected all clones. On average, all clones were able to recover after 4 days of rewatering. Water deficit triggered oxidative stress at the early phase, as evidenced by the upregulation of oxidative stress markers and genes encoding ROS scavenging enzymes. The effects of water deficit stress on energy metabolism were deduced given the upregulation of fermentative enzyme-coding genes. Altogether, our results suggest that the EET8 clone was the highest performing under water deficit while the ICS-60 clone was more susceptible to water stress. Importantly, the activation of the antioxidant system and PSII repair mechanism seem to play key roles in the observed differences in tolerance to water deficit stress among clones.
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Affiliation(s)
| | | | | | - Wilson Terán
- Plant and Crop Biology, Department of Biology, Pontificia Universidad Javeriana, Bogotá, Colombia
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9
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Kleine T, Nägele T, Neuhaus HE, Schmitz-Linneweber C, Fernie AR, Geigenberger P, Grimm B, Kaufmann K, Klipp E, Meurer J, Möhlmann T, Mühlhaus T, Naranjo B, Nickelsen J, Richter A, Ruwe H, Schroda M, Schwenkert S, Trentmann O, Willmund F, Zoschke R, Leister D. Acclimation in plants - the Green Hub consortium. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 106:23-40. [PMID: 33368770 DOI: 10.1111/tpj.15144] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 12/08/2020] [Accepted: 12/14/2020] [Indexed: 05/04/2023]
Abstract
Acclimation is the capacity to adapt to environmental changes within the lifetime of an individual. This ability allows plants to cope with the continuous variation in ambient conditions to which they are exposed as sessile organisms. Because environmental changes and extremes are becoming even more pronounced due to the current period of climate change, enhancing the efficacy of plant acclimation is a promising strategy for mitigating the consequences of global warming on crop yields. At the cellular level, the chloroplast plays a central role in many acclimation responses, acting both as a sensor of environmental change and as a target of cellular acclimation responses. In this Perspective article, we outline the activities of the Green Hub consortium funded by the German Science Foundation. The main aim of this research collaboration is to understand and strategically modify the cellular networks that mediate plant acclimation to adverse environments, employing Arabidopsis, tobacco (Nicotiana tabacum) and Chlamydomonas as model organisms. These efforts will contribute to 'smart breeding' methods designed to create crop plants with improved acclimation properties. To this end, the model oilseed crop Camelina sativa is being used to test modulators of acclimation for their potential to enhance crop yield under adverse environmental conditions. Here we highlight the current state of research on the role of gene expression, metabolism and signalling in acclimation, with a focus on chloroplast-related processes. In addition, further approaches to uncovering acclimation mechanisms derived from systems and computational biology, as well as adaptive laboratory evolution with photosynthetic microbes, are highlighted.
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Affiliation(s)
- Tatjana Kleine
- Plant Molecular Biology, Faculty of Biology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, 82152, Germany
| | - Thomas Nägele
- Plant Evolutionary Cell Biology, Faculty of Biology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Munich, 82152, Germany
| | - H Ekkehard Neuhaus
- Plant Physiology, Department of Biology, Technische Universität Kaiserslautern, Kaiserslautern, 67663, Germany
| | | | - Alisdair R Fernie
- Central Metabolism, Max-Planck-Institut für Molekulare Pflanzenphysiologie, Potsdam-Golm, 14476, Germany
| | - Peter Geigenberger
- Plant Metabolism, Faculty of Biology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Munich, 82152, Germany
| | - Bernhard Grimm
- Plant Physiology, Institute of Biology, Humboldt-Universität zu Berlin, Berlin, 10115, Germany
| | - Kerstin Kaufmann
- Plant Cell and Molecular Biology, Institute of Biology, Humboldt-Universität zu Berlin, Berlin, 10115, Germany
| | - Edda Klipp
- Theoretical Biophysics, Institute of Biology, Humboldt-Universität zu Berlin, Berlin, 10115, Germany
| | - Jörg Meurer
- Plant Molecular Biology, Faculty of Biology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, 82152, Germany
| | - Torsten Möhlmann
- Plant Physiology, Department of Biology, Technische Universität Kaiserslautern, Kaiserslautern, 67663, Germany
| | - Timo Mühlhaus
- Computational Systems Biology, Department of Biology, Technische Universität Kaiserslautern, Kaiserslautern, 67663, Germany
| | - Belen Naranjo
- Plant Molecular Biology, Faculty of Biology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, 82152, Germany
| | - Jörg Nickelsen
- Molecular Plant Science, Faculty of Biology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Munich, 82152, Germany
| | - Andreas Richter
- Physiology of Plant Organelles, Institute of Biology, Humboldt-Universität zu Berlin, Berlin, 10115, Germany
| | - Hannes Ruwe
- Molecular Genetics, Institute of Biology, Humboldt-Universität zu Berlin, Berlin, 10115, Germany
| | - Michael Schroda
- Molecular Biotechnology & Systems Biology, Department of Biology, Technische Universität Kaiserslautern, Kaiserslautern, 67663, Germany
| | - Serena Schwenkert
- Plant Biochemistry and Physiology, Faculty of Biology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Munich, 82152, Germany
| | - Oliver Trentmann
- Plant Physiology, Department of Biology, Technische Universität Kaiserslautern, Kaiserslautern, 67663, Germany
| | - Felix Willmund
- Molecular Genetics of Eukaryotes, Department of Biology, Technische Universität Kaiserslautern, Kaiserslautern, 67663, Germany
| | - Reimo Zoschke
- Translational Regulation in Plants, Max-Planck-Institut für Molekulare Pflanzenphysiologie, Potsdam-Golm, 14476, Germany
| | - Dario Leister
- Plant Molecular Biology, Faculty of Biology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, 82152, Germany
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10
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Ramundo S, Asakura Y, Salomé PA, Strenkert D, Boone M, Mackinder LCM, Takafuji K, Dinc E, Rahire M, Crèvecoeur M, Magneschi L, Schaad O, Hippler M, Jonikas MC, Merchant S, Nakai M, Rochaix JD, Walter P. Coexpressed subunits of dual genetic origin define a conserved supercomplex mediating essential protein import into chloroplasts. Proc Natl Acad Sci U S A 2020; 117:32739-32749. [PMID: 33273113 PMCID: PMC7768757 DOI: 10.1073/pnas.2014294117] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
In photosynthetic eukaryotes, thousands of proteins are translated in the cytosol and imported into the chloroplast through the concerted action of two translocons-termed TOC and TIC-located in the outer and inner membranes of the chloroplast envelope, respectively. The degree to which the molecular composition of the TOC and TIC complexes is conserved over phylogenetic distances has remained controversial. Here, we combine transcriptomic, biochemical, and genetic tools in the green alga Chlamydomonas (Chlamydomonas reinhardtii) to demonstrate that, despite a lack of evident sequence conservation for some of its components, the algal TIC complex mirrors the molecular composition of a TIC complex from Arabidopsis thaliana. The Chlamydomonas TIC complex contains three nuclear-encoded subunits, Tic20, Tic56, and Tic100, and one chloroplast-encoded subunit, Tic214, and interacts with the TOC complex, as well as with several uncharacterized proteins to form a stable supercomplex (TIC-TOC), indicating that protein import across both envelope membranes is mechanistically coupled. Expression of the nuclear and chloroplast genes encoding both known and uncharacterized TIC-TOC components is highly coordinated, suggesting that a mechanism for regulating its biogenesis across compartmental boundaries must exist. Conditional repression of Tic214, the only chloroplast-encoded subunit in the TIC-TOC complex, impairs the import of chloroplast proteins with essential roles in chloroplast ribosome biogenesis and protein folding and induces a pleiotropic stress response, including several proteins involved in the chloroplast unfolded protein response. These findings underscore the functional importance of the TIC-TOC supercomplex in maintaining chloroplast proteostasis.
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Affiliation(s)
- Silvia Ramundo
- Department of Biochemistry and Biophysics, University of California, San Francisco, CA 94143
- Howard Hughes Medical Institute, Chevy Chase, MD 20815
| | - Yukari Asakura
- Laboratory of Organelle Biology, Institute for Protein Research, Osaka University, Osaka 565-0871, Japan
| | - Patrice A Salomé
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
| | - Daniela Strenkert
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
| | - Morgane Boone
- Department of Biochemistry and Biophysics, University of California, San Francisco, CA 94143
- Howard Hughes Medical Institute, Chevy Chase, MD 20815
| | - Luke C M Mackinder
- Department of Biology, University of York, York YO10 5DD, United Kingdom
| | - Kazuaki Takafuji
- Graduate School of Medicine, Osaka University, Osaka 565-0871, Japan
| | - Emine Dinc
- Department of Molecular Biology, University of Geneva, Geneva CH-1211, Switzerland
- Department of Plant Biology, University of Geneva, Geneva CH-1211, Switzerland
| | - Michèle Rahire
- Department of Molecular Biology, University of Geneva, Geneva CH-1211, Switzerland
- Department of Plant Biology, University of Geneva, Geneva CH-1211, Switzerland
| | - Michèle Crèvecoeur
- Department of Molecular Biology, University of Geneva, Geneva CH-1211, Switzerland
- Department of Plant Biology, University of Geneva, Geneva CH-1211, Switzerland
| | - Leonardo Magneschi
- Institute of Plant Biology and Biotechnology, University of Münster, Münster 48143, Germany
| | - Olivier Schaad
- Department of Biochemistry, University of Geneva, Geneva CH-1211, Switzerland
| | - Michael Hippler
- Institute of Plant Biology and Biotechnology, University of Münster, Münster 48143, Germany
- Institute of Plant Science and Resources, Okayama University, Kurashiki 710-0046, Japan
| | - Martin C Jonikas
- Department of Molecular Biology, Princeton University, Princeton, NJ 08540
- Howard Hughes Medical Institute, Chevy Chase, MD 20815
| | - Sabeeha Merchant
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
| | - Masato Nakai
- Laboratory of Organelle Biology, Institute for Protein Research, Osaka University, Osaka 565-0871, Japan;
| | - Jean-David Rochaix
- Department of Molecular Biology, University of Geneva, Geneva CH-1211, Switzerland;
- Department of Plant Biology, University of Geneva, Geneva CH-1211, Switzerland
| | - Peter Walter
- Department of Biochemistry and Biophysics, University of California, San Francisco, CA 94143;
- Howard Hughes Medical Institute, Chevy Chase, MD 20815
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11
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Mamaeva A, Taliansky M, Filippova A, Love AJ, Golub N, Fesenko I. The role of chloroplast protein remodeling in stress responses and shaping of the plant peptidome. THE NEW PHYTOLOGIST 2020; 227:1326-1334. [PMID: 32320487 DOI: 10.1111/nph.16620] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 04/15/2020] [Indexed: 06/11/2023]
Abstract
In addition to photosynthesis, chloroplasts perform a variety of important cellular functions in the plant cell, which can, for example, regulate plant responses to abiotic and biotic stress conditions. Under stress, intensive chloroplast protein remodeling and degradation can occur, releasing large numbers of endogenous peptides. These protein-derived peptides can be found intracellularly, but also in the plant secretome. Although the pathways of chloroplast protein degradation and the types of chloroplast proteases implicated in this process have received much attention, the role of the resulting peptides is less well understood. In this review we summarize the data on peptide generation processes during the remodeling of the chloroplast proteome under stress conditions and discuss the mechanisms leading to these changes. We also review the experimental evidence which supports the concept that peptides derived from chloroplast proteins can function as regulators of plant responses to (a)biotic stresses.
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Affiliation(s)
- Anna Mamaeva
- Laboratory of Plant Functional Genomics and Proteomics, Laboratory of Molecular Basis of Plant Stress Resistance, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of Sciences, Miklukho-Maklaya 16/10, 117997, Moscow, Russian Federation
| | - Michael Taliansky
- Laboratory of Plant Functional Genomics and Proteomics, Laboratory of Molecular Basis of Plant Stress Resistance, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of Sciences, Miklukho-Maklaya 16/10, 117997, Moscow, Russian Federation
- The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK
| | - Anna Filippova
- Laboratory of Plant Functional Genomics and Proteomics, Laboratory of Molecular Basis of Plant Stress Resistance, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of Sciences, Miklukho-Maklaya 16/10, 117997, Moscow, Russian Federation
| | - Andrew J Love
- The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK
| | - Nina Golub
- Laboratory of Plant Functional Genomics and Proteomics, Laboratory of Molecular Basis of Plant Stress Resistance, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of Sciences, Miklukho-Maklaya 16/10, 117997, Moscow, Russian Federation
| | - Igor Fesenko
- Laboratory of Plant Functional Genomics and Proteomics, Laboratory of Molecular Basis of Plant Stress Resistance, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of Sciences, Miklukho-Maklaya 16/10, 117997, Moscow, Russian Federation
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12
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Fang G, Yang S, Ruan B, Liu C, Zhang A, Jiang H, Ding S, Tian B, Zhang Y, Jahan N, Zhu L, Zhang G, Dong G, Zhang Q, Zeng D, Guo L, Gao Z, Qian Q. Isolation of TSCD11 Gene for Early Chloroplast Development under High Temperature in Rice. RICE (NEW YORK, N.Y.) 2020; 13:49. [PMID: 32681435 PMCID: PMC7367945 DOI: 10.1186/s12284-020-00411-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Accepted: 07/08/2020] [Indexed: 05/11/2023]
Abstract
BACKGROUND Chloroplasts are essential for photosynthesis and play key roles in plant development. High temperature affects structure of chloroplasts and metabolism in plants. The seryl-tRNA synthetase plays an important role in translation of proteins. Although seryl-tRNA synthetase has been widely studied in microbes and animals, few studies have reported about its role in chloroplast development under high temperature in rice. RESULTS In this study, we isolated a novel temperature-sensitive chlorophyll-deficient 11 (tscd11) mutant by ethyl methane sulfonate (EMS) mutagenesis of japonica variety Wuyujing7. The tscd11 mutant developed albino leaves at the 3-leaf stage under high temperature (35 °C), but had normal green leaves under low temperature (25 °C). Consistent with the albino phenotype, impaired chloroplasts, decreased chlorophyll content and increased ROS accumulation were found in the tscd11 mutant at 35 °C. Fine mapping and DNA sequencing of tscd11 revealed a missense mutation (G to A) in the eighth exon of LOC_Os11g39670 resulted in amino acid change (Glu374 to Lys374). The TSCD11 gene encodes a seryl-tRNA synthetase localized to chloroplast. Complementation test confirmed that the point mutation in TSCD11 is responsible for the phenotype of tscd11. TSCD11 is highly expressed in leaves. Compared with the wild type (WT), mutation in TSCD11 led to significant alteration in expression levels of genes associated with chlorophyll biosynthesis, photosynthesis and chloroplast development under high temperature. CONCLUSIONS TSCD11, encoding a seryl-tRNA synthetase localized to chloroplast, is vital to early chloroplast development at high temperature in rice, which help to further study on the molecular mechanism of chloroplast development under high temperature.
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Affiliation(s)
- Guonan Fang
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Shenglong Yang
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Banpu Ruan
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Chaolei Liu
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Anpeng Zhang
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Hongzhen Jiang
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Shilin Ding
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Biao Tian
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Yu Zhang
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Noushin Jahan
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Li Zhu
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Guangheng Zhang
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Guojun Dong
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Qiang Zhang
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Dali Zeng
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Longbiao Guo
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China
| | - Zhenyu Gao
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China.
| | - Qian Qian
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006, China.
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13
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Protein import into chloroplasts and its regulation by the ubiquitin-proteasome system. Biochem Soc Trans 2020; 48:71-82. [PMID: 31922184 PMCID: PMC7054747 DOI: 10.1042/bst20190274] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 12/19/2019] [Accepted: 12/23/2019] [Indexed: 02/08/2023]
Abstract
Chloroplasts are photosynthetic plant organelles descended from a bacterial ancestor. The vast majority of chloroplast proteins are synthesized in the cytosol and then imported into the chloroplast post-translationally. Translocation complexes exist in the organelle's outer and inner envelope membranes (termed TOC and TIC, respectively) to facilitate protein import. These systems recognize chloroplast precursor proteins and mediate their import in an energy-dependent manner. However, many unanswered questions remain regarding mechanistic details of the import process and the participation and functions of individual components; for example, the cytosolic events that mediate protein delivery to chloroplasts, the composition of the TIC apparatus, and the nature of the protein import motor all require resolution. The flux of proteins through TOC and TIC varies greatly throughout development and in response to specific environmental cues. The import process is, therefore, tightly regulated, and it has emerged that the ubiquitin-proteasome system (UPS) plays a key role in this regard, acting at several different steps in the process. The UPS is involved in: the selective degradation of transcription factors that co-ordinate the expression of chloroplast precursor proteins; the removal of unimported chloroplast precursor proteins in the cytosol; the inhibition of chloroplast biogenesis pre-germination; and the reconfiguration of the TOC apparatus in response to developmental and environmental signals in a process termed chloroplast-associated protein degradation. In this review, we highlight recent advances in our understanding of protein import into chloroplasts and how this process is regulated by the UPS.
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14
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Seo SY, Wi SJ, Park KY. Functional switching of NPR1 between chloroplast and nucleus for adaptive response to salt stress. Sci Rep 2020; 10:4339. [PMID: 32152424 PMCID: PMC7062895 DOI: 10.1038/s41598-020-61379-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 02/13/2020] [Indexed: 02/02/2023] Open
Abstract
Salt stress causes rapid accumulation of nonexpressor of pathogenesis-related genes 1 (NPR1) protein, known as the redox-sensitive transcription coactivator, which in turn elicits many adaptive responses. The NPR1 protein transiently accumulates in chloroplast stroma under salt stress, which attenuates stress-triggered down-regulation of photosynthetic capability. We observed that oligomeric NPR1 in chloroplasts and cytoplasm had chaperone activity, whereas monomeric NPR1 in the nucleus did not. Additionally, NPR1 overexpression resulted in reinforcement of morning-phased and evening-phased circadian clock. NPR1 overexpression also enhanced antioxidant activity and reduced stress-induced reactive oxygen species (ROS) generation at early stage, followed with transcription levels for ROS detoxification. These results suggest a functional switch from a molecular chaperone to a transcriptional coactivator, which is dependent on subcellular localization. Our findings imply that dual localization of NPR1 is related to proteostasis and redox homeostasis in chloroplasts for emergency restoration as well as transcriptional coactivator in the nucleus for adaptation to stress.
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Affiliation(s)
- So Yeon Seo
- Department of Biology, Sunchon National University, Sunchon, Chonnam, Republic of Korea
| | - Soo Jin Wi
- Department of Biology, Sunchon National University, Sunchon, Chonnam, Republic of Korea
| | - Ky Young Park
- Department of Biology, Sunchon National University, Sunchon, Chonnam, Republic of Korea.
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15
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Eisa A, Malenica K, Schwenkert S, Bölter B. High Light Acclimation Induces Chloroplast Precursor Phosphorylation and Reduces Import Efficiency. PLANTS 2019; 9:plants9010024. [PMID: 31878089 PMCID: PMC7020187 DOI: 10.3390/plants9010024] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 12/19/2019] [Accepted: 12/22/2019] [Indexed: 12/14/2022]
Abstract
Acclimation is an essential process in plants on many levels, but especially in chloroplasts under changing light conditions. It is partially known how the photosynthetic machinery reacts upon exposure to high light intensities, including rearrangement of numerous protein complexes. Since the majority of proteins residing within chloroplasts needs to be posttranslationally imported into the organelles, we endeavored to study how this important process is regulated upon subjecting plants from pea and Arabidopsis to high light. Our results reveal that acclimation takes place on the one hand in the cytosol by differential phosphorylation of preproteins and resulting from the altered expression of the responsible kinases, and on the other hand at the level of the translocation machineries in the outer (TOC) and inner (TIC) envelope membranes. Intriguingly, while phosphorylation is more pronounced under high light, import itself shows a lower efficiency, along with a reduced accumulation of the Toc receptor proteins Toc34 and Toc159.
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16
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Treatment of Sweet Pepper with Stress Tolerance-Inducing Compounds Alleviates Salinity Stress Oxidative Damage by Mediating the Physio-Biochemical Activities and Antioxidant Systems. AGRONOMY-BASEL 2019. [DOI: 10.3390/agronomy10010026] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Salinity stress occurs due to the accumulation of high levels of salts in soil, which ultimately leads to the impairment of plant growth and crop loss. Stress tolerance-inducing compounds have a remarkable ability to improve growth and minimize the effects of salinity stress without negatively affecting the environment by controlling the physiological and molecular activities in plants. Two pot experiments were carried out in 2017 and 2018 to study the influence of salicylic acid (1 mM), yeast extract (6 g L−1), and proline (10 mM) on the physiological and biochemical parameters of sweet pepper plants under saline conditions (2000 and 4000 ppm). The results showed that salt stress led to decreasing the chlorophyll content, relative water content, and fruit yields, whereas electrolyte leakage, malondialdehyde (MDA), proline concentration, reactive oxygen species (ROS), and the activities of antioxidant enzymes increased in salt-stressed plants. The application of salicylic acid (1 mM), yeast extract (6 g L−1), and proline (10 mM) markedly improved the physiological characteristics and fruit yields of salt-stressed plants compared with untreated stressed plants. A significant reduction in electrolyte leakage, MDA, and ROS was also recorded for all treatments. In conclusion, our results reveal the important role of proline, SA, and yeast extracts in enhancing sweet pepper growth and tolerance to salinity stress via modulation of the physiological parameters and antioxidants machinery. Interestingly, proline proved to be the best treatment.
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17
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Synthetic Protein Scaffolding at Biological Membranes. Trends Biotechnol 2019; 38:432-446. [PMID: 31718802 DOI: 10.1016/j.tibtech.2019.10.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 10/18/2019] [Accepted: 10/21/2019] [Indexed: 02/07/2023]
Abstract
Protein scaffolding is a natural phenomenon whereby proteins colocalize into macromolecular complexes via specific protein-protein interactions. In the case of metabolic enzymes, protein scaffolding drives metabolic flux through specific pathways by colocalizing enzyme active sites. Synthetic protein scaffolding is increasingly used as a mechanism to improve product specificity and yields in metabolic engineering projects. To date, synthetic scaffolding has focused primarily on soluble enzyme systems, but many metabolic pathways for high-value secondary metabolites depend on membrane-bound enzymes. The compositional diversity of biological membranes and general challenges associated with modifying membrane proteins complicate scaffolding with membrane-requiring enzymes. Several recent studies have introduced new approaches to protein scaffolding at membrane surfaces, with notable success in improving product yields from specific metabolic pathways.
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