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Rabeh K, Oubohssaine M, Hnini M. TOR in plants: Multidimensional regulators of plant growth and signaling pathways. JOURNAL OF PLANT PHYSIOLOGY 2024; 294:154186. [PMID: 38330538 DOI: 10.1016/j.jplph.2024.154186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 01/20/2024] [Accepted: 01/22/2024] [Indexed: 02/10/2024]
Abstract
Target Of Rapamycin (TOR) represents a ubiquitous kinase complex that has emerged as a central regulator of cell growth and metabolism in nearly all eukaryotic organisms. TOR is an evolutionarily conserved protein kinase, functioning as a central signaling hub that integrates diverse internal and external cues to regulate a multitude of biological processes. These processes collectively exert significant influence on plant growth, development, nutrient assimilation, photosynthesis, fruit ripening, and interactions with microorganisms. Within the plant domain, the TOR complex comprises three integral components: TOR, RAPTOR, and LST8. This comprehensive review provides insights into various facets of the TOR protein, encompassing its origin, structure, function, and the regulatory and signaling pathways operative in photosynthetic organisms. Additionally, we explore future perspectives related to this pivotal protein kinase.
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Affiliation(s)
- Karim Rabeh
- Microbiology and Molecular Biology Team, Center of Plant and Microbial Biotechnologies, Biodiversity and Environment, Faculty of Sciences, Mohammed V University, Rabat, Morocco.
| | - Malika Oubohssaine
- Microbiology and Molecular Biology Team, Center of Plant and Microbial Biotechnologies, Biodiversity and Environment, Faculty of Sciences, Mohammed V University, Rabat, Morocco
| | - Mohamed Hnini
- Microbiology and Molecular Biology Team, Center of Plant and Microbial Biotechnologies, Biodiversity and Environment, Faculty of Sciences, Mohammed V University, Rabat, Morocco
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Cadena-Ramos AI, De-la-Peña C. Picky eaters: selective autophagy in plant cells. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 117:364-384. [PMID: 37864806 DOI: 10.1111/tpj.16508] [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: 07/14/2023] [Revised: 09/21/2023] [Accepted: 10/10/2023] [Indexed: 10/23/2023]
Abstract
Autophagy, a fundamental cellular process, plays a vital role in maintaining cellular homeostasis by degrading damaged or unnecessary components. While selective autophagy has been extensively studied in animal cells, its significance in plant cells has only recently gained attention. In this review, we delve into the intriguing realm selective autophagy in plants, with specific focus on its involvement in nutrient recycling, organelle turnover, and stress response. Moreover, recent studies have unveiled the interesting interplay between selective autophagy and epigenetic mechanisms in plants, elucidating the significance of epigenetic regulation in modulating autophagy-related gene expression and finely tuning the selective autophagy process in plants. By synthesizing existing knowledge, this review highlights the emerging field of selective autophagy in plant cells, emphasizing its pivotal role in maintaining nutrient homeostasis, facilitating cellular adaptation, and shedding light on the epigenetic regulation that governs these processes. Our comprehensive study provides the way for a deeper understanding of the dynamic control of cellular responses to nutrient availability and stress conditions, opening new avenues for future research in this field of autophagy in plant physiology.
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Affiliation(s)
- Alexis I Cadena-Ramos
- Unidad de Biotecnología, Centro de Investigación Científica de Yucatán, Calle 43 No. 130 x 32 y 34 Col. Chuburná de Hidalgo, 97205, Mérida, Yucatán, Mexico
| | - Clelia De-la-Peña
- Unidad de Biotecnología, Centro de Investigación Científica de Yucatán, Calle 43 No. 130 x 32 y 34 Col. Chuburná de Hidalgo, 97205, Mérida, Yucatán, Mexico
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Wang Q, Zhou X, He S, Wang W, Ma D, Wang Y, Zhang H. Receptor Plants Alleviated Allelopathic Stress from Invasive Chenopodium ambrosioides L. by Upregulating the Production and Autophagy of Their Root Border Cells. PLANTS (BASEL, SWITZERLAND) 2023; 12:3810. [PMID: 38005707 PMCID: PMC10674979 DOI: 10.3390/plants12223810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Revised: 10/23/2023] [Accepted: 10/31/2023] [Indexed: 11/26/2023]
Abstract
Chenopodium ambrosioides L. is an invasive plant native to the Neotropics that has seriously threatened the ecological security of China, and allelopathy is one of the mechanisms underlying its successful invasion. Maize (Zea mays L.) and soybean (Glycine max (L.) Merr.), as the main food crops, are usually affected by C. ambrosioides in their planting areas. The purpose of this study was to investigate the ultrastructure, autophagy, and release-related gene expression of receptor plant root border cells (RBCs) after exposure to volatile oil from C. ambrosioides and its main component α-terpene, which were studied using maize and soybean as receptor plants. The volatiles inhibited root growth and promoted a brief increase in the number of RBCs. As the volatile concentration increased, the organelles in RBCs were gradually destroyed, and intracellular autophagosomes were produced and continuously increased in number. Transcriptomic analysis revealed that genes involved in the synthesis of the plasma membrane and cell wall components in receptor root cells were significantly up-regulated, particularly those related to cell wall polysaccharide synthesis. Meanwhile, polygalacturonase and pectin methylesterases (PME) exhibited up-regulated expression, and PME activity also increased. The contribution of α-terpene to this allelopathic effect of C. ambrosioides volatile oil exceeded 70%. Based on these results, receptor plant root tips may increase the synthesis of cell wall substances while degrading the intercellular layer, accelerating the generation and release of RBCs. Meanwhile, their cells survived through autophagy of RBCs, indicating the key role of RBCs in alleviating allelopathic stress from C. ambrosioides volatiles.
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Affiliation(s)
- Qiang Wang
- College of Life Science, Sichuan Normal University, Chengdu 610101, China; (Q.W.); (X.Z.); (S.H.); (Y.W.); (H.Z.)
| | - Xijie Zhou
- College of Life Science, Sichuan Normal University, Chengdu 610101, China; (Q.W.); (X.Z.); (S.H.); (Y.W.); (H.Z.)
| | - Shengli He
- College of Life Science, Sichuan Normal University, Chengdu 610101, China; (Q.W.); (X.Z.); (S.H.); (Y.W.); (H.Z.)
| | - Wenguo Wang
- Key Laboratory of Development and Application of Rural Renewable Energy, Biogas Institute of Ministry of Agriculture and Rural Affairs, Chengdu 610041, China
| | - Danwei Ma
- College of Life Science, Sichuan Normal University, Chengdu 610101, China; (Q.W.); (X.Z.); (S.H.); (Y.W.); (H.Z.)
| | - Yu Wang
- College of Life Science, Sichuan Normal University, Chengdu 610101, China; (Q.W.); (X.Z.); (S.H.); (Y.W.); (H.Z.)
| | - Hong Zhang
- College of Life Science, Sichuan Normal University, Chengdu 610101, China; (Q.W.); (X.Z.); (S.H.); (Y.W.); (H.Z.)
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Barros JAS, Chatt EC, Augustine RC, McLoughlin F, Li F, Otegui MS, Vierstra RD. Autophagy during maize endosperm development dampens oxidative stress and promotes mitochondrial clearance. PLANT PHYSIOLOGY 2023; 193:1395-1415. [PMID: 37335933 PMCID: PMC10517192 DOI: 10.1093/plphys/kiad340] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 05/10/2023] [Accepted: 05/10/2023] [Indexed: 06/21/2023]
Abstract
The selective turnover of macromolecules by autophagy provides a critical homeostatic mechanism for recycling cellular constituents and for removing superfluous and damaged organelles, membranes, and proteins. To better understand how autophagy impacts seed maturation and nutrient storage, we studied maize (Zea mays) endosperm in its early and middle developmental stages via an integrated multiomic approach using mutants impacting the core macroautophagy factor AUTOPHAGY (ATG)-12 required for autophagosome assembly. Surprisingly, the mutant endosperm in these developmental windows accumulated normal amounts of starch and Zein storage proteins. However, the tissue acquired a substantially altered metabolome, especially for compounds related to oxidative stress and sulfur metabolism, including increases in cystine, dehydroascorbate, cys-glutathione disulfide, glucarate, and galactarate, and decreases in peroxide and the antioxidant glutathione. While changes in the associated transcriptome were mild, the proteome was strongly altered in the atg12 endosperm, especially for increased levels of mitochondrial proteins without a concomitant increase in mRNA abundances. Although fewer mitochondria were seen cytologically, a heightened number appeared dysfunctional based on the accumulation of dilated cristae, consistent with attenuated mitophagy. Collectively, our results confirm that macroautophagy plays a minor role in the accumulation of starch and storage proteins during maize endosperm development but likely helps protect against oxidative stress and clears unneeded/dysfunctional mitochondria during tissue maturation.
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Affiliation(s)
- Jessica A S Barros
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Elizabeth C Chatt
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Robert C Augustine
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Fionn McLoughlin
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Faqiang Li
- Department of Genetics, University of Wisconsin, Madison, WI 53706, USA
| | - Marisa S Otegui
- Department of Botany, University of Wisconsin, Madison, WI 53706, USA
- Center for Quantitative Cell Imaging, University of Wisconsin, Madison, WI 53706, USA
| | - Richard D Vierstra
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130, USA
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Shen C, Wei C, Wu Y. Barley yellow dwarf Virus-GAV movement protein activating wheat TaATG6-Mediated antiviral autophagy pathway. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2023; 200:107771. [PMID: 37247558 DOI: 10.1016/j.plaphy.2023.107771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 05/04/2023] [Accepted: 05/15/2023] [Indexed: 05/31/2023]
Abstract
Barley yellow dwarf virus-GAV (BYDV-GAV) is a highly destructive virus that is transmitted by aphids and can cause substantial yield losses in crops such as wheat (Triticum aestivum), barley (Hordeum vulgare) and oat (Avena sativa). Autophagy is an evolutionarily conserved degradation process that eliminates damaged or harmful intracellular substances during stress conditions or specific developmental processes. However, the mechanism of autophagy involved in disease resistance in wheat remains unknown. In this study, we demonstrate that BYDV-GAV infection could induces the upregulation of genes related to the autophagy pathway in wheat, accompanied by the production of autophagosomes. Furthermore, we confirmed the direct interaction between the viral movement protein (MP) and wheat autophagy-related gene 6 (TaATG6) both in vivo and in vitro. Through yeast function complementation experiments, we determined that TaATG6 can restore the autophagy function in a yeast mutant, atg6. Additionally, we identified the interaction between TaATG6 and TaATG8, core factors of the autophagic pathway, using the yeast two-hybrid system. TaATG6 and TaATG8-silenced wheat plants exhibited a high viral content. Overall, our findings suggest that wheat can recognize BYDV-GAV infection and activate the MP-TaATG6-TaATG8 regulatory network of defense responses through the induction of the autophagy pathway.
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Affiliation(s)
- Chuan Shen
- Shaannan Eco-economy Research Center, Ankang University, 725000, Ankang, China.
| | - Caiyan Wei
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, Northwest A&F University, 712100, Yangling, China
| | - Yunfeng Wu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, Northwest A&F University, 712100, Yangling, China
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Chen J, Chen S, Xu C, Yang H, Achom M, Wang X. A key virulence effector from cyst nematodes targets host autophagy to promote nematode parasitism. THE NEW PHYTOLOGIST 2023; 237:1374-1390. [PMID: 36349395 DOI: 10.1111/nph.18609] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 11/02/2022] [Indexed: 06/16/2023]
Abstract
Autophagy, an intracellular degradation system conserved in eukaryotes, has been increasingly recognized as a key battlefield in plant-pathogen interactions. However, the role of plant autophagy in nematode parasitism is mostly unknown. We report here the identification of a novel and conserved effector, Nematode Manipulator of Autophagy System 1 (NMAS1), from plant-parasitic cyst nematodes (Heterodera and Globodera spp.). We used molecular and genetic analyses to demonstrate that NMAS1 is required for nematode parasitism. The NMAS1 effectors are potent suppressors of reactive oxygen species (ROS) induced by flg22 and cell death mediated by immune receptors in Nicotiana benthamiana, suggesting a key role of NMAS1 effectors in nematode virulence. Arabidopsis atg mutants defective in autophagy showed reduced susceptibility to nematode infection. The NMAS1 effectors contain predicted AuTophaGy-related protein 8 (ATG8)-interacting motif (AIM) sequences. In planta protein-protein interaction assays further demonstrated that NMAS1 effectors specifically interact with host plant ATG8 proteins. Interestingly, mutation in AIM2 of GrNMAS1 from the potato cyst nematode Globodera rostochiensis abolishes its interaction with potato StATG8 proteins and its activity in ROS suppression. Collectively, our results reveal for the first time that cyst nematodes employ a conserved AIM-containing virulence effector capable of targeting a key component of host autophagy to promote disease.
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Affiliation(s)
- Jiansong Chen
- School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, USA
- Rice Research Institute & Guangdong Key Laboratory of New Technology in Rice Breeding, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, China
- Department of Plant Pathology, College of Plant Protection, South China Agricultural University, Guangzhou, 510642, China
| | - Shiyan Chen
- School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, USA
| | - Chunling Xu
- School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, USA
- Department of Plant Pathology, College of Plant Protection, South China Agricultural University, Guangzhou, 510642, China
| | - Huijun Yang
- Robert W. Holley Center for Agriculture and Health, US Department of Agriculture, Agricultural Research Service, Ithaca, NY, 14853, USA
| | - Mingkee Achom
- School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, USA
| | - Xiaohong Wang
- School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, USA
- Robert W. Holley Center for Agriculture and Health, US Department of Agriculture, Agricultural Research Service, Ithaca, NY, 14853, USA
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Qing Z, Ahmad S, Chen Y, Liang Q, Zhang L, Chen B, Wen R. P3/P3N-PIPO of PVY interacting with BI-1 inhibits the degradation of NIb by ATG6 to facilitate virus replication in N. benthamiana. FRONTIERS IN PLANT SCIENCE 2023; 14:1183144. [PMID: 37139112 PMCID: PMC10149851 DOI: 10.3389/fpls.2023.1183144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 03/31/2023] [Indexed: 05/05/2023]
Abstract
Introduction Autophagy not only plays an antiviral role but also can be utilized by viruses to facilitate virus infection. However, the underlying mechanism of potato virus Y (PVY) infection against plant autophagy remains unclear. BI-1, localizing to the endoplasmic reticulum (ER), is a multifunctional protein and may affect the virus infection. Methods In this study, Y2H, BiFC, qRT-PCR, RNA-Seq, WB and so on were used for research. Results P3 and P3N-PIPO of PVY can interact with the Bax inhibitor 1 (BI-1) of N. benthamiana. However, BI-1 knockout mutant showed better growth and development ability. In addition, when the BI-1 gene was knocked out or knocked down in N. benthamiana, the PVY-infected mutant showed milder symptoms and lower virus accumulation. Analysis of transcriptome data showed that the deletion of NbBI-1 weakened the gene expression regulation induced by PVY infection and NbBI-1 may reduce the mRNA level of NbATG6 by regulated IRE1-dependent decay (RIDD) in PVY-infected N. benthamiana. The expression level of the ATG6 gene of PVY-infected WT was significantly down-regulated, relative to the PVY-infected mutant. Further results showed that ATG6 of N. benthamiana can degrade NIb, the RNA-dependent RNA polymerase (RdRp) of PVY. NbATG6 has a higher mRNA level in PVY-infected BI-1 knockout mutants than in PVY-infected WT. Conclussion The interaction of P3 and/or P3N-PIPO of PVY with BI-1 decrease the expression of the ATG6 gene might be mediated by RIDD, which inhibits the degradation of viral NIb and enhances viral replication.
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Affiliation(s)
- Zhen Qing
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, Nanning, China
| | - Shakeel Ahmad
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, Nanning, China
| | - Yuemeng Chen
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, Nanning, China
| | - Qingmin Liang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, Nanning, China
| | - Lijuan Zhang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, Nanning, China
| | - Baoshan Chen
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, Nanning, China
- College of Agriculture, Guangxi University, Nanning, China
| | - Ronghui Wen
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Life Science and Technology, Guangxi University, Nanning, China
- *Correspondence: Ronghui Wen,
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Che R, Liu C, Wang Q, Tu W, Wang P, Li C, Gong X, Mao K, Feng H, Huang L, Li P, Ma F. The Valsa mali effector Vm1G-1794 protects the aggregated MdEF-Tu from autophagic degradation to promote infection in apple. Autophagy 2022:1-19. [DOI: 10.1080/15548627.2022.2153573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Affiliation(s)
- Runmin Che
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Changhai Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Qi Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Wenyan Tu
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Ping Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Chao Li
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Xiaoqing Gong
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Ke Mao
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Hao Feng
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Lili Huang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Pengmin Li
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Fengwang Ma
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
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Qi H, Lei X, Wang Y, Yu S, Liu T, Zhou SK, Chen JY, Chen QF, Qiu RL, Jiang L, Xiao S. 14-3-3 proteins contribute to autophagy by modulating SINAT-mediated degradation of ATG13. THE PLANT CELL 2022; 34:4857-4876. [PMID: 36053201 PMCID: PMC9709989 DOI: 10.1093/plcell/koac273] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 08/16/2022] [Indexed: 05/07/2023]
Abstract
In multicellular eukaryotes, autophagy is a conserved process that delivers cellular components to the vacuole or lysosome for recycling during development and stress responses. Induction of autophagy activates AUTOPHAGY-RELATED PROTEIN 1 (ATG1) and ATG13 to form a protein kinase complex that initiates autophagosome formation. However, the detailed molecular mechanism underlying the regulation of this protein complex in plants remains unclear. Here, we determined that in Arabidopsis thaliana, the regulatory proteins 14-3-3λ and 14-3-3κ redundantly modulate autophagy dynamics by facilitating SEVEN IN ABSENTIA OF ARABIDOPSIS THALIANA (SINAT)-mediated proteolysis of ATG13a and ATG13b. 14-3-3λ and 14-3-3κ directly interacted with SINATs and ATG13a/b in vitro and in vivo. Compared to wild-type (WT), the 14-3-3λ 14-3-3κ double mutant showed increased tolerance to nutrient starvation, delayed leaf senescence, and enhanced starvation-induced autophagic vesicles. Moreover, 14-3-3s were required for SINAT1-mediated ubiquitination and degradation of ATG13a. Consistent with their roles in ATG degradation, the 14-3-3λ 14-3-3κ double mutant accumulated higher levels of ATG1a/b/c and ATG13a/b than the WT upon nutrient deprivation. Furthermore, the specific association of 14-3-3s with phosphorylated ATG13a was crucial for ATG13a stability and formation of the ATG1-ATG13 complex. Thus, our findings demonstrate that 14-3-3λ and 14-3-3κ function as molecular adaptors to regulate autophagy by modulating the homeostasis of phosphorylated ATG13.
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Affiliation(s)
- Hua Qi
- Guangdong Laboratory for Lingnan Modern Agriculture, State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
- Guangdong Provincial Key Laboratory of Agricultural & Rural Pollution Abatement and Environmental Safety, College of Natural Resources and Environment, South China Agricultural University, Guangzhou, 510642, China
| | - Xue Lei
- Guangdong Laboratory for Lingnan Modern Agriculture, State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Yao Wang
- Guangdong Laboratory for Lingnan Modern Agriculture, State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Shan Yu
- Guangdong Laboratory for Lingnan Modern Agriculture, State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Ting Liu
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Plant Protection, South China Agricultural University, Guangzhou, 510642, China
| | - Shun-Kang Zhou
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Plant Protection, South China Agricultural University, Guangzhou, 510642, China
| | - Jin-Yu Chen
- Guangdong Laboratory for Lingnan Modern Agriculture, State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Qin-Fang Chen
- Guangdong Laboratory for Lingnan Modern Agriculture, State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Rong-Liang Qiu
- Guangdong Provincial Key Laboratory of Agricultural & Rural Pollution Abatement and Environmental Safety, College of Natural Resources and Environment, South China Agricultural University, Guangzhou, 510642, China
| | - Liwen Jiang
- School of Life Sciences, Centre for Cell & Developmental Biology, State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Shi Xiao
- Guangdong Laboratory for Lingnan Modern Agriculture, State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
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Niu E, Ye C, Zhao W, Kondo H, Wu Y, Chen J, Andika IB, Sun L. Coat protein of Chinese wheat mosaic virus upregulates and interacts with cytosolic glyceraldehyde-3-phosphate dehydrogenase, a negative regulator of plant autophagy, to promote virus infection. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2022; 64:1631-1645. [PMID: 35713231 DOI: 10.1111/jipb.13313] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Accepted: 06/15/2022] [Indexed: 06/15/2023]
Abstract
Autophagy is an intracellular degradation mechanism involved in antiviral defense, but the strategies employed by plant viruses to counteract autophagy-related defense remain unknown for the majority of the viruses. Herein, we describe how the Chinese wheat mosaic virus (CWMV, genus Furovirus) interferes with autophagy and enhances its infection in Nicotiana benthamiana. Yeast two-hybrid screening and in vivo/in vitro assays revealed that the 19 kDa coat protein (CP19K) of CWMV interacts with cytosolic glyceraldehyde-3-phosphate dehydrogenases (GAPCs), negative regulators of autophagy, which bind autophagy-related protein 3 (ATG3), a key factor in autophagy. CP19K also directly interacts with ATG3, possibly leading to the formation of a CP19K-GAPC-ATG3 complex. CP19K-GAPC interaction appeared to intensify CP19K-ATG3 binding. Moreover, CP19K expression upregulated GAPC gene transcripts and reduced autophagic activities. Accordingly, the silencing of GAPC genes in transgenic N. benthamiana reduced CWMV accumulation, whereas CP19K overexpression enhanced it. Overall, our results suggest that CWMV CP19K interferes with autophagy through the promotion and utilization of the GAPC role as a negative regulator of autophagy.
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Affiliation(s)
- Erbo Niu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, Northwest A&F University, Xi'an, 712100, China
| | - Chaozheng Ye
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, Northwest A&F University, Xi'an, 712100, China
| | - Wanying Zhao
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, Northwest A&F University, Xi'an, 712100, China
| | - Hideki Kondo
- Institute of Plant Science and Resources, Okayama University, Kurashiki, 710-0046, Japan
| | - Yunfeng Wu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, Northwest A&F University, Xi'an, 712100, China
| | - Jianping Chen
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Institute of Plant Virology, Ningbo University, Ningbo, 315211, China
| | - Ida Bagus Andika
- College of Plant Health and Medicine, Qingdao Agricultural University, Qingdao, 266109, China
| | - Liying Sun
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, Northwest A&F University, Xi'an, 712100, China
- Institute of Plant Science and Resources, Okayama University, Kurashiki, 710-0046, Japan
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11
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Koyro HW, Huchzermeyer B. From Soil Amendments to Controlling Autophagy: Supporting Plant Metabolism under Conditions of Water Shortage and Salinity. PLANTS 2022; 11:plants11131654. [PMID: 35807605 PMCID: PMC9269222 DOI: 10.3390/plants11131654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 06/03/2022] [Accepted: 06/16/2022] [Indexed: 11/30/2022]
Abstract
Crop resistance to environmental stress is a major issue. The globally increasing land degradation and desertification enhance the demand on management practices to balance both food and environmental objectives, including strategies that tighten nutrient cycles and maintain yields. Agriculture needs to provide, among other things, future additional ecosystem services, such as water quantity and quality, runoff control, soil fertility maintenance, carbon storage, climate regulation, and biodiversity. Numerous research projects have focused on the food–soil–climate nexus, and results were summarized in several reviews during the last decades. Based on this impressive piece of information, we have selected only a few aspects with the intention of studying plant–soil interactions and methods for optimization. In the short term, the use of soil amendments is currently attracting great interest to cover the current demand in agriculture. We will discuss the impact of biochar at water shortage, and plant growth promoting bacteria (PGPB) at improving nutrient supply to plants. In this review, our focus is on the interplay of both soil amendments on primary reactions of photosynthesis, plant growth conditions, and signaling during adaptation to environmental stress. Moreover, we aim at providing a general overview of how dehydration and salinity affect signaling in cells. With the use of the example of abscisic acid (ABA) and ethylene, we discuss the effects that can be observed when biochar and PGPB are used in the presence of stress. The stress response of plants is a multifactorial trait. Nevertheless, we will show that plants follow a general concept to adapt to unfavorable environmental conditions in the short and long term. However, plant species differ in the upper and lower regulatory limits of gene expression. Therefore, the presented data may help in the identification of traits for future breeding of stress-resistant crops. One target for breeding could be the removal and efficient recycling of damaged as well as needless compounds and structures. Furthermore, in this context, we will show that autophagy can be a useful goal of breeding measures, since the recycling of building blocks helps the cells to overcome a period of imbalanced substrate supply during stress adjustment.
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Affiliation(s)
- Hans-Werner Koyro
- Institute of Plantecology, Justus-Liebig-University, Heinrich-Buff-Ring 26, 35392 Giessen, Germany
- Correspondence:
| | - Bernhard Huchzermeyer
- Institute of Botany, Leibniz Universitaet Hannover, Herrenhaeuser Str. 2, 30416 Hannover, Germany; or
- AK Biotechnology, VDI-BV-Hannover, Hanomagstr. 12, 30449 Hannover, Germany
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12
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Wang Y, Wang G, Xu W, Zhang Z, Sun X, Zhang S. Exogenous Melatonin Improves Pear Resistance to Botryosphaeria dothidea by Increasing Autophagic Activity and Sugar/Organic Acid Levels. PHYTOPATHOLOGY 2022; 112:1335-1344. [PMID: 34989595 DOI: 10.1094/phyto-11-21-0489-r] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Pear is an important fruit tree worldwide, but it is often infected by the pathogen Botryosphaeria dothidea, which causes pear ring rot disease. To explore the effect of exogenous melatonin on the disease resistance of pear, we treated inoculated pear fruits with different concentrations of melatonin. The results showed that 100 μΜ of melatonin had the most significant effect with resistance to B. dothidea. In addition, melatonin treatment significantly reduced the diameter of disease lesions and enhanced the endogenous melatonin content in pears inoculated with B. dothidea. Compared with the control treatment, melatonin treatment suppressed increases in reactive oxygen species (ROS) and activated ROS-scavenging enzymes. Treatment with exogenous melatonin maintained ascorbic acid-glutathione at more reductive status. The expression levels of core autophagic genes and autophagosome formation were elevated by melatonin treatment in pear fruits. Silencing of PbrATG5 in Pyrus pyrifolia conferred sensitivity to inoculation that was only slightly attenuated by melatonin treatment. After inoculation with B. dothidea, exogenous melatonin treatment led to higher levels of soluble sugars and organic acids in pear fruits than H2O treatment. Overall, our results demonstrate that melatonin enhances resistance to B. dothidea by increasing autophagic activity and soluble sugar/organic acid accumulation.
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Affiliation(s)
- Yun Wang
- Center of Pear Engineering Technology Research, State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
| | - Guoming Wang
- Center of Pear Engineering Technology Research, State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
| | - Wenyu Xu
- Center of Pear Engineering Technology Research, State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
| | - Zhenwu Zhang
- Center of Pear Engineering Technology Research, State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
| | - Xun Sun
- Center of Pear Engineering Technology Research, State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
| | - Shaoling Zhang
- Center of Pear Engineering Technology Research, State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
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13
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Xu C, Fan J. Links between autophagy and lipid droplet dynamics. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:2848-2858. [PMID: 35560198 DOI: 10.1093/jxb/erac003] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 01/06/2022] [Indexed: 06/15/2023]
Abstract
Autophagy is a catabolic process in which cytoplasmic components are delivered to vacuoles or lysosomes for degradation and nutrient recycling. Autophagy-mediated degradation of membrane lipids provides a source of fatty acids for the synthesis of energy-rich, storage lipid esters such as triacylglycerol (TAG). In eukaryotes, storage lipids are packaged into dynamic subcellular organelles, lipid droplets. In times of energy scarcity, lipid droplets can be degraded via autophagy in a process termed lipophagy to release fatty acids for energy production via fatty acid β-oxidation. On the other hand, emerging evidence suggests that lipid droplets are required for the efficient execution of autophagic processes. Here, we review recent advances in our understanding of metabolic interactions between autophagy and TAG storage, and discuss mechanisms of lipophagy. Free fatty acids are cytotoxic due to their detergent-like properties and their incorporation into lipid intermediates that are toxic at high levels. Thus, we also discuss how cells manage lipotoxic stresses during autophagy-mediated mobilization of fatty acids from lipid droplets and organellar membranes for energy generation.
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Affiliation(s)
- Changcheng Xu
- Biology Department, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Jilian Fan
- Biology Department, Brookhaven National Laboratory, Upton, NY 11973, USA
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14
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Zheng P, Zheng C, Otegui MS, Li F. Endomembrane mediated-trafficking of seed storage proteins: from Arabidopsis to cereal crops. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:1312-1326. [PMID: 34849750 DOI: 10.1093/jxb/erab519] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Accepted: 11/25/2021] [Indexed: 06/13/2023]
Abstract
Seed storage proteins (SSPs) are of great importance in plant science and agriculture, particularly in cereal crops, due to their nutritional value and their impact on food properties. During seed maturation, massive amounts of SSPs are synthesized and deposited either within protein bodies derived from the endoplasmic reticulum, or into specialized protein storage vacuoles (PSVs). The processing and trafficking of SSPs vary among plant species, tissues, and even developmental stages, as well as being influenced by SSP composition. The different trafficking routes, which affect the amount of SSPs that seeds accumulate and their composition and modifications, rely on a highly dynamic and functionally specialized endomembrane system. Although the general steps in SSP trafficking have been studied in various plants, including cereals, the detailed underlying molecular and regulatory mechanisms are still elusive. In this review, we discuss the main endomembrane routes involved in SSP trafficking to the PSV in Arabidopsis and other eudicots, and compare and contrast the SSP trafficking pathways in major cereal crops, particularly in rice and maize. In addition, we explore the challenges and strategies for analyzing the endomembrane system in cereal crops.
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Affiliation(s)
- Ping Zheng
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, China
- School of Life Science, Huizhou University, Huizhou, China
| | - Chunyan Zheng
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, China
| | - Marisa S Otegui
- Department of Botany, Center for Quantitative Cell Imaging, University of Wisconsin-Madison, WIUSA
| | - Faqiang Li
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, China
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15
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Yang Y, Xiang Y, Niu Y. An Overview of the Molecular Mechanisms and Functions of Autophagic Pathways in Plants. PLANT SIGNALING & BEHAVIOR 2021; 16:1977527. [PMID: 34617497 PMCID: PMC9208794 DOI: 10.1080/15592324.2021.1977527] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 08/29/2021] [Accepted: 08/31/2021] [Indexed: 06/13/2023]
Abstract
Autophagy is an evolutionarily conserved pathway for the degradation of damaged or toxic components. Under normal conditions, autophagy maintains cellular homeostasis. It can be triggered by senescence and various stresses. In the process of autophagy, autophagy-related (ATG) proteins not only function as central signal regulators but also participate in the development of complex survival mechanisms when plants suffer from adverse environments. Therefore, ATGs play significant roles in metabolism, development and stress tolerance. In the past decade, both the molecular mechanisms of autophagy and a large number of components involved in the assembly of autophagic vesicles have been identified. In recent studies, an increasing number of components, mechanisms, and receptors have appeared in the autophagy pathway. In this paper, we mainly review the recent progress of research on the molecular mechanisms of plant autophagy, as well as its function under biotic stress and abiotic stress.
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Affiliation(s)
- Yang Yang
- Moe Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences,Lanzhou University, Lanzhou, China
| | - Yun Xiang
- Moe Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences,Lanzhou University, Lanzhou, China
| | - Yue Niu
- Moe Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences,Lanzhou University, Lanzhou, China
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16
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Ye C, Zheng S, Jiang D, Lu J, Huang Z, Liu Z, Zhou H, Zhuang C, Li J. Initiation and Execution of Programmed Cell Death and Regulation of Reactive Oxygen Species in Plants. Int J Mol Sci 2021; 22:ijms222312942. [PMID: 34884747 PMCID: PMC8657872 DOI: 10.3390/ijms222312942] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 11/19/2021] [Accepted: 11/24/2021] [Indexed: 12/21/2022] Open
Abstract
Programmed cell death (PCD) plays crucial roles in plant development and defence response. Reactive oxygen species (ROS) are produced during normal plant growth, and high ROS concentrations can change the antioxidant status of cells, leading to spontaneous cell death. In addition, ROS function as signalling molecules to improve plant stress tolerance, and they induce PCD under different conditions. This review describes the mechanisms underlying plant PCD, the key functions of mitochondria and chloroplasts in PCD, and the relationship between mitochondria and chloroplasts during PCD. Additionally, the review discusses the factors that regulate PCD. Most importantly, in this review, we summarise the sites of production of ROS and discuss the roles of ROS that not only trigger multiple signalling pathways leading to PCD but also participate in the execution of PCD, highlighting the importance of ROS in PCD.
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Affiliation(s)
- Chanjuan Ye
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China; (C.Y.); (S.Z.); (D.J.); (J.L.); (Z.H.); (Z.L.); (H.Z.); (C.Z.)
- Key Laboratory of Plant Functional Genomics and Biotechnology of Guangdong Provincial Higher Education Institutions, South China Agricultural University, Guangzhou 510642, China
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Shaoyan Zheng
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China; (C.Y.); (S.Z.); (D.J.); (J.L.); (Z.H.); (Z.L.); (H.Z.); (C.Z.)
- Key Laboratory of Plant Functional Genomics and Biotechnology of Guangdong Provincial Higher Education Institutions, South China Agricultural University, Guangzhou 510642, China
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Dagang Jiang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China; (C.Y.); (S.Z.); (D.J.); (J.L.); (Z.H.); (Z.L.); (H.Z.); (C.Z.)
- Key Laboratory of Plant Functional Genomics and Biotechnology of Guangdong Provincial Higher Education Institutions, South China Agricultural University, Guangzhou 510642, China
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Jingqin Lu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China; (C.Y.); (S.Z.); (D.J.); (J.L.); (Z.H.); (Z.L.); (H.Z.); (C.Z.)
- Key Laboratory of Plant Functional Genomics and Biotechnology of Guangdong Provincial Higher Education Institutions, South China Agricultural University, Guangzhou 510642, China
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Zongna Huang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China; (C.Y.); (S.Z.); (D.J.); (J.L.); (Z.H.); (Z.L.); (H.Z.); (C.Z.)
- Key Laboratory of Plant Functional Genomics and Biotechnology of Guangdong Provincial Higher Education Institutions, South China Agricultural University, Guangzhou 510642, China
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Zhenlan Liu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China; (C.Y.); (S.Z.); (D.J.); (J.L.); (Z.H.); (Z.L.); (H.Z.); (C.Z.)
- Key Laboratory of Plant Functional Genomics and Biotechnology of Guangdong Provincial Higher Education Institutions, South China Agricultural University, Guangzhou 510642, China
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Hai Zhou
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China; (C.Y.); (S.Z.); (D.J.); (J.L.); (Z.H.); (Z.L.); (H.Z.); (C.Z.)
- Key Laboratory of Plant Functional Genomics and Biotechnology of Guangdong Provincial Higher Education Institutions, South China Agricultural University, Guangzhou 510642, China
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Chuxiong Zhuang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China; (C.Y.); (S.Z.); (D.J.); (J.L.); (Z.H.); (Z.L.); (H.Z.); (C.Z.)
- Key Laboratory of Plant Functional Genomics and Biotechnology of Guangdong Provincial Higher Education Institutions, South China Agricultural University, Guangzhou 510642, China
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Jing Li
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Sciences, South China Agricultural University, Guangzhou 510642, China; (C.Y.); (S.Z.); (D.J.); (J.L.); (Z.H.); (Z.L.); (H.Z.); (C.Z.)
- Key Laboratory of Plant Functional Genomics and Biotechnology of Guangdong Provincial Higher Education Institutions, South China Agricultural University, Guangzhou 510642, China
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
- Correspondence:
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17
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Jia X, Jia X, Li T, Wang Y, Sun X, Huo L, Wang P, Che R, Gong X, Ma F. MdATG5a induces drought tolerance by improving the antioxidant defenses and promoting starch degradation in apple. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2021; 312:111052. [PMID: 34620447 DOI: 10.1016/j.plantsci.2021.111052] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 08/29/2021] [Accepted: 09/03/2021] [Indexed: 06/13/2023]
Abstract
Drought occurrence seriously affects the productivity and quality of apple crop worldwide. Autophagy, a conserved process for the degradation and recycling of unwanted cellular components, is considered to positively regulate the tolerance of various abiotic stresses in plants. In the current study, we isolated two ATG5 homologs genes, namely, MdATG5a and MdATG5b, from apple, demonstrating their responsiveness to drought and oxidative stresses. In addition to having the same cellular localization in the nucleus and cytoplasm, both MdATG5a and MdATG5b could interact with MdATG12. Transgenic apple plants overexpressing MdATG5a exhibited an improved drought tolerance, as indicated by less drought-related damage and higher photosynthetic capacities compared to wild-type (WT) plants under drought stress. The overexpression of MdATG5a improved antioxidant defenses in apple when exposed to drought via elevating both antioxidant enzyme activities and the levels of beneficial antioxidants. Furthermore, under drought stress, the overexpression of MdATG5a promoted the mobilization of starch to accumulate greater levels of soluble sugars, contributing to osmotic adjustments and supporting carbon skeletons for proline synthesis. Such changes in physiological responses may be associated with increased autophagic activities in the transgenic plants upon exposure to drought. Our results demonstrate that MdATG5a-mediated autophagy enhances drought tolerance of apple plants via improving antioxidant defenses and metabolic adjustments.
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Affiliation(s)
- Xin Jia
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Xumei Jia
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Tiantian Li
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Yu Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Xun Sun
- Center of Pear Engineering Technology Research, State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Liuqing Huo
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Ping Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Runmin Che
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Xiaoqing Gong
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, 712100, Shaanxi, China.
| | - Fengwang Ma
- State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, 712100, Shaanxi, China.
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18
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Wang P, Fang H, Gao R, Liao W. Protein Persulfidation in Plants: Function and Mechanism. Antioxidants (Basel) 2021; 10:1631. [PMID: 34679765 PMCID: PMC8533255 DOI: 10.3390/antiox10101631] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Revised: 10/10/2021] [Accepted: 10/14/2021] [Indexed: 11/16/2022] Open
Abstract
As an endogenous gaseous transmitter, the function of hydrogen sulfide (H2S) has been extensively studied in plants. Once synthesized, H2S may be involved in almost all life processes of plants. Among them, a key route for H2S bioactivity occurs via protein persulfidation, in which process oxidizes cysteine thiol (R-SH) groups into persulfide (R-SSH) groups. This process is thought to underpin a myriad of cellular processes in plants linked to growth, development, stress responses, and phytohormone signaling. Multiple lines of emerging evidence suggest that this redox-based reversible post-translational modification can not only serve as a protective mechanism for H2S in oxidative stress, but also control a variety of biochemical processes through the allosteric effect of proteins. Here, we collate emerging evidence showing that H2S-mediated persulfidation modification involves some important biochemical processes such as growth and development, oxidative stress, phytohormone and autophagy. Additionally, the interaction between persulfidation and S-nitrosylation is also discussed. In this work, we provide beneficial clues for further exploration of the molecular mechanism and function of protein persulfidation in plants in the future.
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Affiliation(s)
| | | | | | - Weibiao Liao
- College of Horticulture, Gansu Agricultural University, 1 Yinmen Village, Anning District, Lanzhou 730070, China; (P.W.); (H.F.); (R.G.)
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19
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Maintaining the structural and functional homeostasis of the plant endoplasmic reticulum. Dev Cell 2021; 56:919-932. [PMID: 33662257 DOI: 10.1016/j.devcel.2021.02.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 01/21/2021] [Accepted: 02/08/2021] [Indexed: 12/14/2022]
Abstract
The endoplasmic reticulum (ER) is a ubiquitous organelle that is vital to the life of eukaryotic cells. It synthesizes essential lipids and proteins and initiates the glycosylation of intracellular and surface proteins. As such, the ER is necessary for cell growth and communication with the external environment. The ER is also a highly dynamic organelle, whose structure is continuously remodeled through an interaction with the cytoskeleton and the action of specialized ER shapers. Recent and significant advances in ER studies have brought to light conserved and unique features underlying the structure and function of this organelle in plant cells. In this review, exciting developments in the understanding of the mechanisms for plant ER structural and functional homeostasis, particularly those that underpin ER network architecture and ER degradation, are presented and discussed.
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20
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Zhang Y, Min H, Shi C, Xia G, Lai Z. Transcriptome analysis of the role of autophagy in plant response to heat stress. PLoS One 2021; 16:e0247783. [PMID: 33635879 PMCID: PMC7909648 DOI: 10.1371/journal.pone.0247783] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 02/16/2021] [Indexed: 12/12/2022] Open
Abstract
Autophagy plays a critical role in plant heat tolerance in part by targeting heat-induced nonnative proteins for degradation. Autophagy also regulates metabolism, signaling and other processes and it is less understood how the broad function of autophagy affects plant heat stress responses. To address this issue, we performed transcriptome profiling of Arabidopsis wild-type and autophagy-deficient atg5 mutant in response to heat stress. A large number of differentially expressed genes (DEGs) were identified between wild-type and atg5 mutant even under normal conditions. These DEGs are involved not only in metabolism, hormone signaling, stress responses but also in regulation of nucleotide processing and DNA repair. Intriguingly, we found that heat treatment resulted in more robust changes in gene expression in wild-type than in the atg5 mutant plants. The dampening effect of autophagy deficiency on heat-regulated gene expression was associated with already altered expression of many heat-regulated DEGs prior to heat stress in the atg5 mutant. Altered expression of a large number of genes involved in metabolism and signaling in the autophagy mutant prior to heat stress may affect plant response to heat stress. Furthermore, autophagy played a positive role in the expression of defense- and stress-related genes during the early stage of heat stress responses but had little effect on heat-induced expression of heat shock genes. Taken together, these results indicate that the broad role of autophagy in metabolism, cellular homeostasis and other processes can also potentially affect plant heat stress responses and heat tolerance.
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Affiliation(s)
- Yan Zhang
- Department of Landscape and Horticulture, Ecology College, Lishui University, Lishui, Zhejiang, China
- * E-mail:
| | - Haoxuan Min
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Chengchen Shi
- Department of Landscape and Horticulture, Ecology College, Lishui University, Lishui, Zhejiang, China
| | - Gengshou Xia
- Department of Landscape and Horticulture, Ecology College, Lishui University, Lishui, Zhejiang, China
| | - Zhibing Lai
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
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21
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Rigault M, Citerne S, Masclaux-Daubresse C, Dellagi A. Salicylic acid is a key player of Arabidopsis autophagy mutant susceptibility to the necrotrophic bacterium Dickeya dadantii. Sci Rep 2021; 11:3624. [PMID: 33574453 PMCID: PMC7878789 DOI: 10.1038/s41598-021-83067-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 01/08/2021] [Indexed: 12/26/2022] Open
Abstract
Autophagy is a ubiquitous vesicular process for protein and organelle recycling in eukaryotes. In plant, autophagy is reported to play pivotal roles in nutrient recycling, adaptation to biotic and abiotic stresses. The role of autophagy in plant immunity remains poorly understood. Several reports showed enhanced susceptibility of different Arabidopsis autophagy mutants (atg) to necrotrophic fungal pathogens. Interaction of necrotrophic bacterial pathogens with autophagy is overlooked. We then investigated such interaction by inoculating the necrotrophic enterobacterium Dickeya dadantii in leaves of the atg2 and atg5 mutants and an ATG8a overexpressing line. Overexpressing ATG8a enhances plant tolerance to D. dadantii. While atg5 mutant displayed similar susceptibility to the WT, the atg2 mutant exhibited accelerated leaf senescence and enhanced susceptibility upon infection. Both phenotypes were reversed when the sid2 mutation, abolishing SA signaling, was introduced in the atg2 mutant. High levels of SA signaling in atg2 mutant resulted in repression of the jasmonic acid (JA) defense pathway known to limit D. dadantii progression in A. thaliana. We provide evidence that in atg2 mutant, the disturbed hormonal balance leading to higher SA signaling is the main factor causing increased susceptibility to the D. dadantii necrotroph by repressing the JA pathway and accelerating developmental senescence.
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Affiliation(s)
- Martine Rigault
- Institut Jean-Pierre Bourgin, UMR1318 INRA-AgroParisTech, INRAE Centre de Versailles-Grignon, Université Paris-Saclay, Route de St Cyr (RD 10), 78000, Versailles Cedex, France
| | - Sylvie Citerne
- Institut Jean-Pierre Bourgin, UMR1318 INRA-AgroParisTech, INRAE Centre de Versailles-Grignon, Université Paris-Saclay, Route de St Cyr (RD 10), 78000, Versailles Cedex, France
| | - Céline Masclaux-Daubresse
- Institut Jean-Pierre Bourgin, UMR1318 INRA-AgroParisTech, INRAE Centre de Versailles-Grignon, Université Paris-Saclay, Route de St Cyr (RD 10), 78000, Versailles Cedex, France
| | - Alia Dellagi
- Institut Jean-Pierre Bourgin, UMR1318 INRA-AgroParisTech, INRAE Centre de Versailles-Grignon, Université Paris-Saclay, Route de St Cyr (RD 10), 78000, Versailles Cedex, France.
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22
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Berenguer E, Minina EA, Carneros E, B�r�ny I, Bozhkov PV, Testillano PS. Suppression of Metacaspase- and Autophagy-Dependent Cell Death Improves Stress-Induced Microspore Embryogenesis in Brassica napus. PLANT & CELL PHYSIOLOGY 2021; 61:2097-2110. [PMID: 33057654 PMCID: PMC7861468 DOI: 10.1093/pcp/pcaa128] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 09/29/2020] [Indexed: 05/12/2023]
Abstract
Microspore embryogenesis is a biotechnological process that allows us to rapidly obtain doubled-haploid plants for breeding programs. The process is initiated by the application of stress treatment, which reprograms microspores to embark on embryonic development. Typically, a part of the microspores undergoes cell death that reduces the efficiency of the process. Metacaspases (MCAs), a phylogenetically broad group of cysteine proteases, and autophagy, the major catabolic process in eukaryotes, are critical regulators of the balance between cell death and survival in various organisms. In this study, we analyzed the role of MCAs and autophagy in cell death during stress-induced microspore embryogenesis in Brassica napus. We demonstrate that this cell death is accompanied by the transcriptional upregulation of three BnMCA genes (BnMCA-Ia, BnMCA-IIa and BnMCA-IIi), an increase in MCA proteolytic activity and the activation of autophagy. Accordingly, inhibition of autophagy and MCA activity, either individually or in combination, suppressed cell death and increased the number of proembryos, indicating that both components play a pro-cell death role and account for decreased efficiency of early embryonic development. Therefore, MCAs and/or autophagy can be used as new biotechnological targets to improve in vitro embryogenesis in Brassica species and doubled-haploid plant production in crop breeding and propagation programs.
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Affiliation(s)
- Eduardo Berenguer
- Microbial and Plant Biotechnology Department, Pollen Biotechnology of Crop Plants Laboratory, Margarita Salas Center of Biological Research, CIB Margarita Salas-CSIC, Ramiro de Maeztu 9, Madrid 28040, Spain
| | - Elena A Minina
- Department of Molecular Sciences, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, PO Box 7015, Uppsala 75007, Sweden
| | - Elena Carneros
- Microbial and Plant Biotechnology Department, Pollen Biotechnology of Crop Plants Laboratory, Margarita Salas Center of Biological Research, CIB Margarita Salas-CSIC, Ramiro de Maeztu 9, Madrid 28040, Spain
| | - Ivett B�r�ny
- Microbial and Plant Biotechnology Department, Pollen Biotechnology of Crop Plants Laboratory, Margarita Salas Center of Biological Research, CIB Margarita Salas-CSIC, Ramiro de Maeztu 9, Madrid 28040, Spain
| | - Peter V Bozhkov
- Department of Molecular Sciences, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, PO Box 7015, Uppsala 75007, Sweden
| | - Pilar S Testillano
- Microbial and Plant Biotechnology Department, Pollen Biotechnology of Crop Plants Laboratory, Margarita Salas Center of Biological Research, CIB Margarita Salas-CSIC, Ramiro de Maeztu 9, Madrid 28040, Spain
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23
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Qi H, Xia FN, Xiao S. Autophagy in plants: Physiological roles and post-translational regulation. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2021; 63:161-179. [PMID: 32324339 DOI: 10.1111/jipb.12941] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 04/22/2020] [Indexed: 05/20/2023]
Abstract
In eukaryotes, autophagy helps maintain cellular homeostasis by degrading and recycling cytoplasmic materials via a tightly regulated pathway. Over the past few decades, significant progress has been made towards understanding the physiological functions and molecular regulation of autophagy in plant cells. Increasing evidence indicates that autophagy is essential for plant responses to several developmental and environmental cues, functioning in diverse processes such as senescence, male fertility, root meristem maintenance, responses to nutrient starvation, and biotic and abiotic stress. Recent studies have demonstrated that, similar to nonplant systems, the modulation of core proteins in the plant autophagy machinery by posttranslational modifications such as phosphorylation, ubiquitination, lipidation, S-sulfhydration, S-nitrosylation, and acetylation is widely involved in the initiation and progression of autophagy. Here, we provide an overview of the physiological roles and posttranslational regulation of autophagy in plants.
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Affiliation(s)
- Hua Qi
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Fan-Nv Xia
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Shi Xiao
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
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24
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Abstract
Autophagy is a conserved vacuole/lysosome-mediated degradation pathway for clearing and recycling cellular components including cytosol, macromolecules, and dysfunctional organelles. In recent years, autophagy has emerged to play important roles in plant-pathogen interactions. It acts as an antiviral defense mechanism in plants. Moreover, increasing evidence shows that plant viruses can manipulate, hijack, or even exploit the autophagy pathway to promote pathogenesis, demonstrating the pivotal role of autophagy in the evolutionary arms race between hosts and viruses. In this review, we discuss recent findings about the antiviral and proviral roles of autophagy in plant-virus interactions.
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Affiliation(s)
- Meng Yang
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China;
| | - Asigul Ismayil
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China;
| | - Yule Liu
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China;
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25
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Ismayil A, Yang M, Liu Y. Role of autophagy during plant-virus interactions. Semin Cell Dev Biol 2020; 101:36-40. [DOI: 10.1016/j.semcdb.2019.07.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 06/17/2019] [Accepted: 07/05/2019] [Indexed: 12/31/2022]
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26
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Abstract
Anionic phospholipids, which include phosphatidic acid, phosphatidylserine, and phosphoinositides, represent a small percentage of membrane lipids. They are able to modulate the physical properties of membranes, such as their surface charges, curvature, or clustering of proteins. Moreover, by mediating interactions with numerous membrane-associated proteins, they are key components in the establishment of organelle identity and dynamics. Finally, anionic lipids also act as signaling molecules, as they are rapidly produced or interconverted by a set of dedicated enzymes. As such, anionic lipids are major regulators of many fundamental cellular processes, including cell signaling, cell division, membrane trafficking, cell growth, and gene expression. In this review, we describe the functions of anionic lipids from a cellular perspective. Using the localization of each anionic lipid and its related metabolic enzymes as starting points, we summarize their roles within the different compartments of the endomembrane system and address their associated developmental and physiological consequences.
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Affiliation(s)
- Lise C Noack
- Laboratoire Reproduction et Développement des Plantes, Université de Lyon, École Normale Supérieure (ENS) de Lyon, L'Université Claude Bernard (UCB) Lyon 1, CNRS, INRAE, 69342 Lyon, France; ,
| | - Yvon Jaillais
- Laboratoire Reproduction et Développement des Plantes, Université de Lyon, École Normale Supérieure (ENS) de Lyon, L'Université Claude Bernard (UCB) Lyon 1, CNRS, INRAE, 69342 Lyon, France; ,
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27
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Lornac A, Havé M, Chardon F, Soulay F, Clément G, Avice JC, Masclaux-Daubresse C. Autophagy Controls Sulphur Metabolism in the Rosette Leaves of Arabidopsis and Facilitates S Remobilization to the Seeds. Cells 2020; 9:E332. [PMID: 32023971 PMCID: PMC7073174 DOI: 10.3390/cells9020332] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 01/28/2020] [Accepted: 01/29/2020] [Indexed: 01/15/2023] Open
Abstract
Sulphur deficiency in crops became an agricultural concern several decades ago, due to the decrease of S deposition and the atmospheric sulphur dioxide emissions released by industrial plants. Autophagy, which is a conserved mechanism for nutrient recycling in eukaryotes, is involved in nitrogen, iron, zinc and manganese remobilizations from the rosette to the seeds in Arabidopsis thaliana. Here, we have compared the role of autophagy in sulphur and nitrogen management at the whole plant level, performing concurrent labelling with 34S and 15N isotopes on atg5 mutants and control lines. We show that both 34S and 15N remobilizations from the rosette to the seeds are impaired in the atg5 mutants irrespective of salicylic acid accumulation and of sulphur nutrition. The comparison in each genotype of the partitions of 15N and 34S in the seeds (as % of the whole plant) indicates that the remobilization of 34S to the seeds was twice more efficient than that of 15N in both autophagy mutants and control lines under high S conditions, and also in control lines under low S conditions. This was different in the autophagy mutants grown under low S conditions. Under low S, the partition of 34S to their seeds was indeed not twice as high but similar to that of 15N. Such discrepancy shows that when sulphate availability is scarce, autophagy mutants display stronger defects for 34S remobilization relative to 15N remobilization than under high S conditions. It suggests, moreover, that autophagy mainly affects the transport of N-poor S-containing molecules and possibly sulphate.
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Affiliation(s)
- Aurélia Lornac
- UCBN, UMR INRA–UCBN 950 Ecophysiologie Végétale &, Agronomie & Nutritions N.C.S., SFR Normandie Végétal (FED 4277), Normandie Université, F-14032 Caen, France
| | - Marien Havé
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000 Versailles, France
| | - Fabien Chardon
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000 Versailles, France
| | - Fabienne Soulay
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000 Versailles, France
| | - Gilles Clément
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000 Versailles, France
| | - Jean-Christophe Avice
- UCBN, UMR INRA–UCBN 950 Ecophysiologie Végétale &, Agronomie & Nutritions N.C.S., SFR Normandie Végétal (FED 4277), Normandie Université, F-14032 Caen, France
| | - Céline Masclaux-Daubresse
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000 Versailles, France
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28
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Kajikawa M, Fukuzawa H. Algal Autophagy Is Necessary for the Regulation of Carbon Metabolism Under Nutrient Deficiency. FRONTIERS IN PLANT SCIENCE 2020; 11:36. [PMID: 32117375 PMCID: PMC7012896 DOI: 10.3389/fpls.2020.00036] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 01/13/2020] [Indexed: 05/04/2023]
Abstract
Autophagy is a mechanism to recycle intracellular constituents such as amino acids and other carbon- and nitrogen (N)-containing compounds. Although autophagy-related (ATG) genes required for autophagy are encoded by many algal genomes, their functional importance in microalgae in nutrient-deficiency has not been appraised using ATG-defective mutants. Recently, by characterization of an insertional mutant of the ATG8 encoding a ubiquitin-like protein indispensable for autophagosome formation in a green alga Chlamydomonas reinhardtii, we have provided evidence that supports the following notions. ATG8 protein is required for the degradation of lipid droplets and triacylglycerol (TAG) triggered by resupply of N to cell culture in N-deficient conditions. ATG8 protein is also necessary for starch accumulation under phosphorus-deficient conditions. Algal autophagy is not necessary for inheritance of chloroplast and mitochondrial genomes. In this review, we discuss the physiological roles of algal autophagy associated with nutrient deficiency revealed by the genetic and biochemical analyses using disruption mutants and reagents that inhibit the fatty acid biosynthesis and vacuolar H+-ATPase.
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29
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Leary AY, Savage Z, Tumtas Y, Bozkurt TO. Contrasting and emerging roles of autophagy in plant immunity. CURRENT OPINION IN PLANT BIOLOGY 2019; 52:46-53. [PMID: 31442734 DOI: 10.1016/j.pbi.2019.07.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 07/08/2019] [Accepted: 07/09/2019] [Indexed: 05/18/2023]
Abstract
Autophagy is a conserved eukaryotic process that mediates degradation and relocation of cellular material to maintain homeostasis and cope with cellular stress. Remarkably, this ancient catabolic machinery has been co-opted to eliminate invading pathogens in a variety of ways. Plant autophagy not only mediates selective destruction of viruses but also limits infection by extracellular bacterial and filamentous pathogens. The emerging paradigm is that autophagy adaptors, responsible for selective cargo sorting, have been appointed to counteract pathogen infection, while adapted pathogens have evolved to subvert the immune functions of the autophagic machinery. In this review, we discuss recent findings that contribute to understanding the role of autophagy in plant immunity and highlight key questions to address in the field moving forward.
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Affiliation(s)
| | - Zachary Savage
- Department of Life Sciences, Imperial College London, London, UK
| | - Yasin Tumtas
- Department of Life Sciences, Imperial College London, London, UK
| | - Tolga O Bozkurt
- Department of Life Sciences, Imperial College London, London, UK.
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30
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OsATG8c-Mediated Increased Autophagy Regulates the Yield and Nitrogen Use Efficiency in Rice. Int J Mol Sci 2019; 20:ijms20194956. [PMID: 31597279 PMCID: PMC6801700 DOI: 10.3390/ijms20194956] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 09/26/2019] [Accepted: 09/27/2019] [Indexed: 12/25/2022] Open
Abstract
Autophagy, a conserved pathway in eukaryotes, degrades and recycles cellular components, thus playing an important role in nitrogen (N) remobilization. N plays an important role in the growth and development of plants, which also affects plant yield and quality. In this research, it was found that the transcriptional level of a core autophagy gene of rice (Oryza sativa), OsATG8c, was increased during N starvation conditions. It was found that the overexpression of OsATG8c significantly enhanced the activity of autophagy and that the number of autophagosomes, dwarfed the plant height and increased the effective tillers’ number and yield. The nitrogen uptake efficiency (NUpE) and nitrogen use efficiency (NUE) significantly increased in the transgenic rice under both optimal and suboptimal N conditions. Based on our results, OsATG8c is considered to be a good candidate gene for increasing NUE, especially under suboptimal field conditions.
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31
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Zhen X, Xu F, Zhang W, Li N, Li X. Overexpression of rice gene OsATG8b confers tolerance to nitrogen starvation and increases yield and nitrogen use efficiency (NUE) in Arabidopsis. PLoS One 2019; 14:e0223011. [PMID: 31553788 PMCID: PMC6760796 DOI: 10.1371/journal.pone.0223011] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Accepted: 09/11/2019] [Indexed: 12/11/2022] Open
Abstract
Nitrogen (N) is an important element required for plant growth and development, which also affects plant yield and quality. Autophagy, a conserved pathway in eukaryotes, degrades and recycles cellular components, thus playing an important role in N remobilization. However, only a few autophagy genes related to N remobilization in rice (Oryza sativa) have been reported. Here, we identified a core autophagy gene in rice, OsATG8b, with increased expression levels under N starvation conditions. It was investigated the function of OsATG8b by generating three independent homozygous 35S-OsATG8b transgenic Arabidopsis thaliana lines. The overexpression of OsATG8b significantly enhanced autophagic flux in the transgenic Arabidopsis plants. It was also showed that over-expressing OsATG8b promoted growth and development of Arabidopsis, in which the rosette leaves were larger than those of the wild type (WT), and the yield increased significantly by 25.25%. In addition, the transgenic lines accumulated more N in seeds than in the rosette leaves. Further examination revealed that overexpression of OsATG8b could effectively alleviate the growth inhibition of transgenic Arabidopsis under nitrogen (N) stress. N partitioning studies revealed that nitrogen-harvest index (NHI) and nitrogen use efficiency (NUE) were significantly increased in the transgenic Arabidopsis, as well as the 15N-tracer experiments revealing that the remobilization of N to seeds in the OsATG8b-overexpressing transgenic Arabidopsis was high and more than WT. Based on our findings, we consider OsATG8b to be a great candidate gene to increase NUE and yield, especially under suboptimal field conditions.
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Affiliation(s)
- Xiaoxi Zhen
- Rice Research Institute of Shenyang Agricultural University, Key Laboratory of Northern Japonica Rice Genetics and Breeding, Ministry of Education and Liaoning Province, Key Laboratory of Northeast Rice Biology and Genetics and Breeding, Ministry of Agriculture, Shenyang, China
| | - Fan Xu
- Rice Research Institute of Shenyang Agricultural University, Key Laboratory of Northern Japonica Rice Genetics and Breeding, Ministry of Education and Liaoning Province, Key Laboratory of Northeast Rice Biology and Genetics and Breeding, Ministry of Agriculture, Shenyang, China
- * E-mail: (FX); (WZ)
| | - Wenzhong Zhang
- Rice Research Institute of Shenyang Agricultural University, Key Laboratory of Northern Japonica Rice Genetics and Breeding, Ministry of Education and Liaoning Province, Key Laboratory of Northeast Rice Biology and Genetics and Breeding, Ministry of Agriculture, Shenyang, China
- * E-mail: (FX); (WZ)
| | - Nan Li
- Shen Yang Product Quality Supervision and Inspection Institute, Shenyang, China
| | - Xin Li
- Rice Research Institute of Shenyang Agricultural University, Key Laboratory of Northern Japonica Rice Genetics and Breeding, Ministry of Education and Liaoning Province, Key Laboratory of Northeast Rice Biology and Genetics and Breeding, Ministry of Agriculture, Shenyang, China
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32
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Machado SR, Rodrigues TM. Autophagy and vacuolar biogenesis during the nectary development. PLANTA 2019; 250:519-533. [PMID: 31104130 DOI: 10.1007/s00425-019-03190-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Accepted: 05/14/2019] [Indexed: 05/26/2023]
Abstract
Different autophagy pathways are a driver of vacuolar biogenesis and are development stage specific during the extrafloral nectary development in Citharexylum myrianthum. Plant autophagy plays an important role in various developmental processes such as seed germination, pollen maturation and leaf senescence. However, studies that address the evidence of autophagy and its role in the development of plant glands are scarce and largely restricted to laticifers. Regarding nectary, studies have repeatedly pointed to signs of degradation associated with the end of the secretory cycle, without exploring autophagy. Likewise, the relationship between autophagy and biogenesis of vacuoles remains an unexplored issue. In this study, using conventional and microwave fixation in association with ultracytochemical methods for transmission electron microscopy, we investigated the occurrence of autophagy and its implication in the differentiation of extrafloral nectary in Citharexylum myrianthum (Verbenaceae) under natural conditions, focusing on the vacuole biogenesis. We described a variety of vacuole types associated with the stage of nectary epidermis development, which differs with respect to origin, function and nature of the products to be stored. Three distinct autophagy pathways were detected: macroautophagy, microautophagy (both restricted to the undifferentiated epidermal cells, at the presecretory stage) and megaautophagy (circumscribed to the differentiated epidermal cells, at the postsecretory stage). Our study clearly demonstrated that the vacuole variety and autophagy processes in the nectary epidermal cells are development specific. This study highlights the role of autophagy in vacuole biogenesis and its implications for the development of nectary and opens new venues for future studies on regulation mechanisms for autophagy in plant secretory structures under normal conditions.
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Affiliation(s)
- Silvia R Machado
- Department of Botany, Institute of Biosciences of Botucatu (IBB), São Paulo State University (UNESP), Botucatu City, SP, Brazil.
- Center of Electron Microscopy (CME), Institute of Biosciences of Botucatu (IBB), São Paulo State University (UNESP), Botucatu City, SP, Brazil.
| | - Tatiane M Rodrigues
- Department of Botany, Institute of Biosciences of Botucatu (IBB), São Paulo State University (UNESP), Botucatu City, SP, Brazil
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33
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Havé M, Luo J, Tellier F, Balliau T, Cueff G, Chardon F, Zivy M, Rajjou L, Cacas JL, Masclaux-Daubresse C. Proteomic and lipidomic analyses of the Arabidopsis atg5 autophagy mutant reveal major changes in endoplasmic reticulum and peroxisome metabolisms and in lipid composition. THE NEW PHYTOLOGIST 2019; 223:1461-1477. [PMID: 31077612 DOI: 10.1111/nph.15913] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Accepted: 04/29/2019] [Indexed: 05/21/2023]
Abstract
Autophagy is a universal mechanism in eukaryotic cells that facilitates the degradation of unwanted cell constituents and is essential for cell homeostasis and nutrient recycling. The salicylic acid-independent effects of autophagy defects on leaf metabolism were determined through large-scale proteomic and lipidomic analyses of atg5 and atg5/sid2 mutants under different nitrogen and sulfur growth conditions. Results revealed that irrespective of the growth conditions, plants carrying the atg5 mutation presented all the characteristics of endoplasmic reticulum (ER) stress. Increases in peroxisome and ER proteins involved in very long chain fatty acid synthesis and β-oxidation indicated strong modifications of lipid metabolism. Lipidomic analyses revealed changes in the concentrations of sphingolipids, phospholipids and galactolipids. Significant accumulations of phospholipids and ceramides and changes in GIPCs (glycosyl-inositol-phosphoryl-ceramides) in atg5 mutants indicated large modifications in endomembrane-lipid and especially plasma membrane-lipid composition. Decreases in chloroplast proteins and galactolipids in atg5 under low nutrient conditions, indicated that chloroplasts were used as lipid reservoirs for β-oxidation in atg5 mutants. In conclusion, this report demonstrates the strong impact of autophagy defect on ER stress and reveals the role of autophagy in the control of plant lipid metabolism and catabolism, influencing both lipid homeostasis and endomembrane composition.
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Affiliation(s)
- Marien Havé
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78000, Versailles, France
| | - Jie Luo
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78000, Versailles, France
| | - Frédérique Tellier
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78000, Versailles, France
| | - Thierry Balliau
- UMR GQE- le Moulon, INRA, Université Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, 91190, Gif-sur-Yvette, France
| | - Gwendal Cueff
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78000, Versailles, France
| | - Fabien Chardon
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78000, Versailles, France
| | - Michel Zivy
- UMR GQE- le Moulon, INRA, Université Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, 91190, Gif-sur-Yvette, France
| | - Loic Rajjou
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78000, Versailles, France
| | - Jean-Luc Cacas
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78000, Versailles, France
| | - Céline Masclaux-Daubresse
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78000, Versailles, France
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34
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Lai LTF, Yu C, Wong JSK, Lo HS, Benlekbir S, Jiang L, Lau WCY. Subnanometer resolution cryo-EM structure of Arabidopsis thaliana ATG9. Autophagy 2019; 16:575-583. [PMID: 31276439 DOI: 10.1080/15548627.2019.1639300] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Macroautophagy/autophagy is an essential process for the maintenance of cellular homeostasis by recycling macromolecules under normal and stress conditions. ATG9 (autophagy related 9) is the only integral membrane protein in the autophagy core machinery and has a central role in mediating autophagosome formation. In cells, ATG9 exists on mobile vesicles that traffic to the growing phagophore, providing an essential membrane source for the formation of autophagosomes. Here we report the three-dimensional structure of ATG9 from Arabidopsis thaliana at 7.8 Å resolution, determined by single particle cryo-electron microscopy. ATG9 organizes into a homotrimer, with each protomer contributing at least six transmembrane α-helices. At the center of the trimer, the protomers interact via their membrane-embedded and C-terminal cytoplasmic regions. Combined with prediction of protein contacts using sequence co-evolutionary information, the structure provides molecular insights into the ATG9 architecture and testable hypotheses for the molecular mechanism of autophagy progression regulated by ATG9.Abbreviations: 2D: 2-dimensional; 3D: 3-dimensional; AtATG9: Arabidopsis ATG9; Atg: autophagy-related; ATG9: autophagy-related protein 9; cryo-EM: cryo-electron microscopy; DDM: dodecyl maltoside; GraDeR: gradient-based detergent removal; LMNG: lauryl maltose-neopentyl glycol; PAS: phagophore assembly site; PtdIns3K: phosphatidylinositol 3-kinase.
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Affiliation(s)
- Louis Tung Faat Lai
- Centre for Cell and Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, China
| | - Chuanyang Yu
- Centre for Cell and Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, China
| | - Jan Siu Kei Wong
- Centre for Cell and Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, China
| | - Ho Sing Lo
- Centre for Cell and Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, China
| | - Samir Benlekbir
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, Canada
| | - Liwen Jiang
- Centre for Cell and Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, China.,CUHK Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, China
| | - Wilson Chun Yu Lau
- Centre for Cell and Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, China
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35
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Yu J, Zhen X, Li X, Li N, Xu F. Increased Autophagy of Rice Can Increase Yield and Nitrogen Use Efficiency (NUE). FRONTIERS IN PLANT SCIENCE 2019; 10:584. [PMID: 31134120 PMCID: PMC6514234 DOI: 10.3389/fpls.2019.00584] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 04/18/2019] [Indexed: 05/28/2023]
Abstract
Autophagy (self-eating), a conserved pathway in eukaryotes, which is designed to handle cytoplasmic material in bulk and plays an important role in the remobilization of nutrient, such as nitrogen (N) under suboptimal nutrient conditions. Here, we identified a core component of an autophagy gene in rice (Oryza sativa), OsATG8a, with increased expression levels under N starvation conditions. Overexpression of OsATG8a significantly enhanced the level of autophagy and the number of effective tillers in the transgenic rice. In addition, the transgenic lines accumulated more N in grains than in the dry remains and the yield was significantly increased under normal N conditions. Further N allocation studies revealed that the nitrogen uptake efficiency (NUpE) and nitrogen use efficiency (NUE) significantly increased. Otherwise, under suboptimal N conditions, overexpression of OsATG8a did not seem to have any effect on yield and NUE, but NUpE was still improved significantly. Based on our findings, we consider OsATG8a to be a great candidate gene to increase NUE and yield.
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Affiliation(s)
- Jinlei Yu
- Key Laboratory of Northern Japonica Rice Genetics and Breeding, Ministry of Education and Liaoning Province – Key Laboratory of Northeast Rice Biology and Genetics and Breeding, Ministry of Agriculture, Rice Research Institute, Shenyang Agricultural University, Shenyang, China
| | - Xiaoxi Zhen
- Key Laboratory of Northern Japonica Rice Genetics and Breeding, Ministry of Education and Liaoning Province – Key Laboratory of Northeast Rice Biology and Genetics and Breeding, Ministry of Agriculture, Rice Research Institute, Shenyang Agricultural University, Shenyang, China
| | - Xin Li
- Key Laboratory of Northern Japonica Rice Genetics and Breeding, Ministry of Education and Liaoning Province – Key Laboratory of Northeast Rice Biology and Genetics and Breeding, Ministry of Agriculture, Rice Research Institute, Shenyang Agricultural University, Shenyang, China
| | - Nan Li
- Shenyang Product Quality Supervision and Inspection Institute, Shenyang, China
| | - Fan Xu
- Key Laboratory of Northern Japonica Rice Genetics and Breeding, Ministry of Education and Liaoning Province – Key Laboratory of Northeast Rice Biology and Genetics and Breeding, Ministry of Agriculture, Rice Research Institute, Shenyang Agricultural University, Shenyang, China
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36
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The Tug-of-War between Plants and Viruses: Great Progress and Many Remaining Questions. Viruses 2019; 11:v11030203. [PMID: 30823402 PMCID: PMC6466000 DOI: 10.3390/v11030203] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 02/18/2019] [Accepted: 02/23/2019] [Indexed: 12/19/2022] Open
Abstract
Plants are persistently challenged by various phytopathogens. To protect themselves, plants have evolved multilayered surveillance against all pathogens. For intracellular parasitic viruses, plants have developed innate immunity, RNA silencing, translation repression, ubiquitination-mediated and autophagy-mediated protein degradation, and other dominant resistance gene-mediated defenses. Plant viruses have also acquired diverse strategies to suppress and even exploit host defense machinery to ensure their survival. A better understanding of the defense and counter-defense between plants and viruses will obviously benefit from the development of efficient and broad-spectrum virus resistance for sustainable agriculture. In this review, we summarize the cutting edge of knowledge concerning the defense and counter-defense between plants and viruses, and highlight the unexploited areas that are especially worth investigating in the near future.
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Chen Q, Soulay F, Saudemont B, Elmayan T, Marmagne A, Masclaux-Daubresse CL. Overexpression of ATG8 in Arabidopsis Stimulates Autophagic Activity and Increases Nitrogen Remobilization Efficiency and Grain Filling. PLANT & CELL PHYSIOLOGY 2019; 60:343-352. [PMID: 30407574 DOI: 10.1093/pcp/pcy214] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 10/27/2018] [Indexed: 05/20/2023]
Abstract
Autophagy knock-out mutants in maize and in Arabidopsis are impaired in nitrogen (N) recycling and exhibit reduced levels of N remobilization to their seeds. It is thus impoortant to determine whether higher autophagy activity could, conversely, improve N remobilization efficiency and seed protein content, and under what circumstances. As the autophagy machinery involves many genes amongst which 18 are important for the core machinery, the choice of which AUTOPHAGY (ATG) gene to manipulate to increase autophagy was examined. We choose ATG8 overexpression since it has been shown that this gene could increase autophagosome size and autophagic activity in yeast. The results we report here are original as they show for the first time that increasing ATG8 gene expression in plants increases autophagosome number and promotes autophagy activity. More importantly, our data demonstrate that, when cultivated under full nitrate conditions, known to repress N remobilization due to sufficient N uptake from the soil, N remobilization efficiency can nevertheless be sharply and significantly increased by overexpressing ATG8 genomic sequences under the control of the ubiquitin promoter. We show that overexpressors have improved seed N% and at the same time reduced N waste in their dry remains. In addition, we show that overexpressing ATG8 does not modify vegetative biomass or harvest index, and thus does not affect plant development.
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Affiliation(s)
- Qinwu Chen
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Universit� Paris-Saclay, Versailles, France
| | - Fabienne Soulay
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Universit� Paris-Saclay, Versailles, France
| | - Baptiste Saudemont
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Universit� Paris-Saclay, Versailles, France
| | - Taline Elmayan
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Universit� Paris-Saclay, Versailles, France
| | - Anne Marmagne
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Universit� Paris-Saclay, Versailles, France
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Janse van Rensburg HC, Van den Ende W, Signorelli S. Autophagy in Plants: Both a Puppet and a Puppet Master of Sugars. FRONTIERS IN PLANT SCIENCE 2019; 10:14. [PMID: 30723485 PMCID: PMC6349728 DOI: 10.3389/fpls.2019.00014] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Accepted: 01/07/2019] [Indexed: 05/20/2023]
Abstract
Autophagy is a major pathway that recycles cellular components in eukaryotic cells both under stressed and non-stressed conditions. Sugars participate both metabolically and as signaling molecules in development and response to various environmental and nutritional conditions. It is therefore essential to maintain metabolic homeostasis of sugars during non-stressed conditions in cells, not only to provide energy, but also to ensure effective signaling when exposed to stress. In both plants and animals, autophagy is activated by the energy sensor SnRK1/AMPK and inhibited by TOR kinase. SnRK1/AMPK and TOR kinases are both important regulators of cellular metabolism and are controlled to a large extent by the availability of sugars and sugar-phosphates in plants whereas in animals AMP/ATP indirectly translate sugar status. In plants, during nutrient and sugar deficiency, SnRK1 is activated, and TOR is inhibited to allow activation of autophagy which in turn recycles cellular components in an attempt to provide stress relief. Autophagy is thus indirectly regulated by the nutrient/sugar status of cells, but also regulates the level of nutrients/sugars by recycling cellular components. In both plants and animals sugars such as trehalose induce autophagy and in animals this is independent of the TOR pathway. The glucose-activated G-protein signaling pathway has also been demonstrated to activate autophagy, although the exact mechanism is not completely clear. This mini-review will focus on the interplay between sugar signaling and autophagy.
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Affiliation(s)
| | - Wim Van den Ende
- Laboratory of Molecular Plant Biology, KU Leuven, Leuven, Belgium
| | - Santiago Signorelli
- Laboratory of Molecular Plant Biology, KU Leuven, Leuven, Belgium
- Departamento de Biologiía Vegetal, Facultad de Agronomía, Universidad de la Repuíblica, Montevideo, Uruguay
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Bao Y, Pu Y, Yu X, Gregory BD, Srivastava R, Howell SH, Bassham DC. IRE1B degrades RNAs encoding proteins that interfere with the induction of autophagy by ER stress in Arabidopsis thaliana. Autophagy 2018; 14:1562-1573. [PMID: 29940799 DOI: 10.1080/15548627.2018.1462426] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Macroautophagy/autophagy is a conserved process in eukaryotes that contributes to cell survival in response to stress. Previously, we found that endoplasmic reticulum (ER) stress induces autophagy in plants via a pathway dependent upon AT5G24360/IRE1B (INOSITOL REQUIRING 1-1), an ER membrane-anchored factor involved in the splicing of AT1G42990/BZIP60 (basic leucine zipper protein 60) mRNA. IRE1B is a dual protein kinase and ribonuclease, and here we determined the involvement of the protein kinase catalytic domain, nucleotide binding and RNase domains of IRE1B in activating autophagy. We found that the nucleotide binding and RNase activity of IRE1B, but not its protein kinase activity or splicing target BZIP60, are required for ER stress-mediated autophagy. Upon ER stress, the RNase activity of IRE1B engages in regulated IRE1-dependent decay of messenger RNA (RIDD), in which mRNAs of secreted proteins are degraded by IRE1 upon ER stress. Twelve genes most highly targeted by RIDD were tested for their role in inhibiting ER stress-induced autophagy, and 3 of their encoded proteins, AT1G66270/BGLU21 (β-glucosidase 21), AT2G16005/ROSY1/ML (MD2-related lipid recognition protein) and AT5G01870/PR-14 (pathogenesis-related protein 14), were found to inhibit autophagy upon overexpression. From these findings, IRE1B is posited to be a 'licensing factor' linking ER stress to autophagy by degrading the RNA transcripts of factors that interfere with the induction of autophagy. ABBREVIATIONS ACT2: actin 2; ATG: autophagy-related; BGLU21: β-glucosidase 21; BIP3: binding protein 3; BZIP: basic leucine zipper; DAPI: 4', 6-diamidino-2-phenylindole; DTT: dithiothreitol; ER: endoplasmic reticulum; ERN1: endoplasmic reticulum to nucleus signaling 1; IRE1: inositol requiring 1; GFP: green fluorescent protein; MAP3K5/ASK1: mitogen-activated protein kinase kinase kinase 5; MAPK8/JNK1: mitogen-activated protein kinase 8/c-Jun N-terminal kinase 1; MDC: monodansylcadaverine; PR-14: pathogenesis-related protein 14; RIDD: Regulated IRE1-Dependent Decay of Messenger RNA; ROSY1/ML: interactor of synaptotagmin1/MD2-related lipid recognition protein; Tm: tunicamycin; UPR: unfolded protein response; WT: wild-type.
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Affiliation(s)
- Yan Bao
- a Department of Genetics, Development and Cell Biology , Iowa State University , Ames , IA , USA
| | - Yunting Pu
- a Department of Genetics, Development and Cell Biology , Iowa State University , Ames , IA , USA.,b Interdepartmental Genetics and Genomics Program , Iowa State University , Ames , IA , USA
| | - Xiang Yu
- c Department of Biology , University of Pennsylvania , Philadelphia , PA , USA
| | - Brian D Gregory
- c Department of Biology , University of Pennsylvania , Philadelphia , PA , USA
| | - Renu Srivastava
- d Plant Sciences Institute , Iowa State University , Ames , IA , USA
| | - Stephen H Howell
- a Department of Genetics, Development and Cell Biology , Iowa State University , Ames , IA , USA.,d Plant Sciences Institute , Iowa State University , Ames , IA , USA
| | - Diane C Bassham
- a Department of Genetics, Development and Cell Biology , Iowa State University , Ames , IA , USA.,b Interdepartmental Genetics and Genomics Program , Iowa State University , Ames , IA , USA
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40
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Zheng P, Wu JX, Sahu SK, Zeng HY, Huang LQ, Liu Z, Xiao S, Yao N. Loss of alkaline ceramidase inhibits autophagy in Arabidopsis and plays an important role during environmental stress response. PLANT, CELL & ENVIRONMENT 2018; 41:837-849. [PMID: 29341143 DOI: 10.1111/pce.13148] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 01/10/2018] [Accepted: 01/10/2018] [Indexed: 05/02/2023]
Abstract
Sphingolipids, a class of bioactive lipids found in cell membranes, can modulate the biophysical properties of the membranes and play a critical role in signal transduction. Sphingolipids are involved in autophagy in humans and yeast, but their role in autophagy in plants is not well understood. In this study, we reported that the AtACER, an alkaline ceramidase that hydrolyses ceramide to long-chain base (LCB), functions in autophagy process in Arabidopsis. Our empirical data showed that the loss of AtACER inhibited autophagy, and its overexpression promoted autophagy under nutrient, salinity, and oxidative stresses. Interestingly, nitrogen deprivation significantly affected the sphingolipid's profile in Arabidopsis thaliana, especially the LCBs. Furthermore, the exogenous application of LCBs also induced autophagy. Our findings revealed a novel function of AtACER, where it was found to involve in the autophagy process, thus, playing a crucial role in the maintenance of a dynamic loop between sphingolipids and autophagy for cellular homeostasis under various environmental stresses.
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Affiliation(s)
- Ping Zheng
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resource, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, P. R. China
| | - Jian-Xin Wu
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resource, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, P. R. China
- Guangdong Key Lab of Biotechnology for Plant Development, College of Life Science, South China Normal University, Guangzhou, 510631, P. R. China
| | - Sunil Kumar Sahu
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resource, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, P. R. China
| | - Hong-Yun Zeng
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resource, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, P. R. China
| | - Li-Qun Huang
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resource, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, P. R. China
| | - Zhe Liu
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resource, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, P. R. China
| | - Shi Xiao
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resource, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, P. R. China
| | - Nan Yao
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resource, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, P. R. China
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41
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Zhou S, Hong Q, Li Y, Li Q, Wang M. Autophagy contributes to regulate the ROS levels and PCD progress in TMV-infected tomatoes. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2018; 269:12-19. [PMID: 29606209 DOI: 10.1016/j.plantsci.2017.11.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 10/10/2017] [Accepted: 11/01/2017] [Indexed: 06/08/2023]
Abstract
Programmed cell death (PCD) and autophagy are both important means for plants to resist pathogen. It is also the main biological reaction of plant immunity. In previous studies, we found that TMV local-infection on tomato leaves not only caused the PCD process in the distal root tissues, but also induced autophagy in root-tip cells. However, the reasons for these biological phenomena are unclear. In order to get deeper insight, the role of a putative inducible factor reactive oxidative species (ROS) was investigated. The situ staining and subcellular localization analysis showed that the ROS level in the root tissue of TMV infected plants was significantly promoted. TEM observation showed that the intracellular ROS was excreted into the cell wall and intercellular layer. At the same time, the results of western blot and qRT-PCR showed that the expression of autophagy related protein Atg8 and genes (Atg5, Atg7 and Atg10) were increased. However, in the subsequent DPI inhibition experiments we found that the accumulation of ROS in infected plant root-tip tissues was inhibited and the autophagy in the root-tip cells also decreased. When 3-methyladenine (3-MA) was used to inhibit autophagy, there was no significant change in the ROS level in the apical tissue, while the systemic PCD process of the root-tip cells was elevated. Taken together, these results indicate that local TMV inoculation on the leaves induced the root-tip cells producing and releasing a lot of ROS into the extracellular matrix for defense against pathogen invasion. Meanwhile, ROS acted as a signaling substance and triggered autophagy in root-tip cells, in order to eliminate excessive intracellular ROS oxidative damage and maintain cell survival.
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Affiliation(s)
- Shumin Zhou
- Lab of Plant Cell Biology, Shanghai Key Laboratory of Bio-Energy Crops, School of Life Sciences, Shanghai University, Shanghai 200444, China
| | - Qiang Hong
- Lab of Plant Cell Biology, Shanghai Key Laboratory of Bio-Energy Crops, School of Life Sciences, Shanghai University, Shanghai 200444, China
| | - Yang Li
- Lab of Plant Cell Biology, Shanghai Key Laboratory of Bio-Energy Crops, School of Life Sciences, Shanghai University, Shanghai 200444, China
| | - Qi Li
- Lab of Plant Cell Biology, Shanghai Key Laboratory of Bio-Energy Crops, School of Life Sciences, Shanghai University, Shanghai 200444, China
| | - Mao Wang
- College of Biology, China Agricultural University, Beijing 100094, China.
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Enrique Gomez R, Joubès J, Valentin N, Batoko H, Satiat-Jeunemaître B, Bernard A. Lipids in membrane dynamics during autophagy in plants. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:1287-1299. [PMID: 29140451 DOI: 10.1093/jxb/erx392] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 10/09/2017] [Indexed: 05/19/2023]
Abstract
Autophagy is a critical pathway for plant adaptation to stress. Macroautophagy relies on the biogenesis of a specialized membrane named the phagophore that maturates into a double membrane vesicle. Proteins and lipids act synergistically to promote membrane structure and functions, yet research on autophagy has mostly focused on autophagy-related proteins while knowledge of supporting lipids in the formation of autophagic membranes remains scarce. This review expands on studies in plants with examples from other organisms to present and discuss our current understanding of lipids in membrane dynamics associated with the autophagy pathway in plants.
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Affiliation(s)
- Rodrigo Enrique Gomez
- CNRS, Laboratoire de Biogenèse Membranaire, UMR5200, Bordeaux, France
- Université de Bordeaux, Laboratoire de Biogenèse Membranaire, UMR5200, Bordeaux, France
| | - Jérôme Joubès
- CNRS, Laboratoire de Biogenèse Membranaire, UMR5200, Bordeaux, France
- Université de Bordeaux, Laboratoire de Biogenèse Membranaire, UMR5200, Bordeaux, France
| | - Nicolas Valentin
- Institute for Integrative Biology of the Cell (I2BC), CNRS, CEA, Paris-Sud University, Avenue de la Terrasse, Gif-sur-Yvette, France
| | - Henri Batoko
- Institut des Sciences de la Vie, Université catholique de Louvain, Croix du Sud 4-L7.07.14, Louvain-la-Neuve, Belgium
| | - Béatrice Satiat-Jeunemaître
- Institute for Integrative Biology of the Cell (I2BC), CNRS, CEA, Paris-Sud University, Avenue de la Terrasse, Gif-sur-Yvette, France
| | - Amélie Bernard
- CNRS, Laboratoire de Biogenèse Membranaire, UMR5200, Bordeaux, France
- Université de Bordeaux, Laboratoire de Biogenèse Membranaire, UMR5200, Bordeaux, France
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43
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Bárány I, Berenguer E, Solís MT, Pérez-Pérez Y, Santamaría ME, Crespo JL, Risueño MC, Díaz I, Testillano PS. Autophagy is activated and involved in cell death with participation of cathepsins during stress-induced microspore embryogenesis in barley. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:1387-1402. [PMID: 29309624 PMCID: PMC6019037 DOI: 10.1093/jxb/erx455] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 11/30/2017] [Indexed: 05/02/2023]
Abstract
Microspores are reprogrammed towards embryogenesis by stress. Many microspores die after this stress, limiting the efficiency of microspore embryogenesis. Autophagy is a degradation pathway that plays critical roles in stress response and cell death. In animals, cathepsins have an integral role in autophagy by degrading autophagic material; less is known in plants. Plant cathepsins are papain-like C1A cysteine proteases involved in many physiological processes, including programmed cell death. We have analysed the involvement of autophagy in cell death, in relation to cathepsin activation, during stress-induced microspore embryogenesis in Hordeum vulgare. After stress, reactive oxygen species (ROS) and cell death increased and autophagy was activated, including HvATG5 and HvATG6 up-regulation and increase of ATG5, ATG8, and autophagosomes. Concomitantly, cathepsin L/F-, B-, and H-like activities were induced, cathepsin-like genes HvPap-1 and HvPap-6 were up-regulated, and HvPap-1, HvPap-6, and HvPap-19 proteins increased and localized in the cytoplasm, resembling autophagy structures. Inhibitors of autophagy and cysteine proteases reduced cell death and promoted embryogenesis. The findings reveal a role for autophagy in stress-induced cell death during microspore embryogenesis, and the participation of cathepsins. Similar patterns of activation, expression, and localization suggest a possible connection between cathepsins and autophagy. The results open up new possibilities to enhance microspore embryogenesis efficiency with autophagy and/or cysteine protease modulators.
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Affiliation(s)
| | | | | | | | | | - José Luis Crespo
- Institute of Plant Biochemistry and Photosynthesis, IBVF, CSIC, Seville, Spain
| | | | - Isabel Díaz
- Center of Plant Biotechnology and Genomics, CBGP, UPM, Madrid, Spain
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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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45
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Marion J, Le Bars R, Besse L, Batoko H, Satiat-Jeunemaitre B. Multiscale and Multimodal Approaches to Study Autophagy in Model Plants. Cells 2018; 7:E5. [PMID: 29315263 PMCID: PMC5789278 DOI: 10.3390/cells7010005] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2017] [Revised: 01/05/2018] [Accepted: 01/05/2018] [Indexed: 12/31/2022] Open
Abstract
Autophagy is a catabolic process used by eukaryotic cells to maintain or restore cellular and organismal homeostasis. A better understanding of autophagy in plant biology could lead to an improvement of the recycling processes of plant cells and thus contribute, for example, towards reducing the negative ecological consequences of nitrogen-based fertilizers in agriculture. It may also help to optimize plant adaptation to adverse biotic and abiotic conditions through appropriate plant breeding or genetic engineering to incorporate useful traits in relation to this catabolic pathway. In this review, we describe useful protocols for studying autophagy in the plant cell, taking into account some specificities of the plant model.
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Affiliation(s)
- Jessica Marion
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91 198 Gif-sur-Yvette, France; (J.M.); (R.L.B.); (L.B.); (B.S.-J.)
| | - Romain Le Bars
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91 198 Gif-sur-Yvette, France; (J.M.); (R.L.B.); (L.B.); (B.S.-J.)
| | - Laetitia Besse
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91 198 Gif-sur-Yvette, France; (J.M.); (R.L.B.); (L.B.); (B.S.-J.)
| | - Henri Batoko
- Institute of Life Sciences, UCL/ISV, University of Louvain, Croix du Sud 4, L7.07.14, 1348 Louvain-la-Neuve, Belgium
| | - Béatrice Satiat-Jeunemaitre
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91 198 Gif-sur-Yvette, France; (J.M.); (R.L.B.); (L.B.); (B.S.-J.)
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46
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Pu Y, Soto-Burgos J, Bassham DC. Regulation of autophagy through SnRK1 and TOR signaling pathways. PLANT SIGNALING & BEHAVIOR 2017; 12:e1395128. [PMID: 29058995 PMCID: PMC5792129 DOI: 10.1080/15592324.2017.1395128] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 10/17/2017] [Indexed: 05/20/2023]
Abstract
Autophagy is important for degradation and recycling of cytoplasmic materials in all eukaryotes and is often triggered by environmental stress. How autophagy is activated in plants under different environmental conditions is still poorly understood. Our recent studies show that induction of autophagy by different abiotic stress conditions can occur via either a TOR-dependent or -independent pathway, depending on the stress. The SnRK1 protein kinase complex acts upstream of TOR in regulation of autophagy during nutrient deficiency, salt and osmotic stresses. In contrast, oxidative and ER stress regulate autophagy in a SnRK1-dependent but TOR-independent manner. Here we summarize and discuss these distinct pathways for activation of autophagy under different environmental stress conditions.
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Affiliation(s)
- Yunting Pu
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, IA, USA
| | - Junmarie Soto-Burgos
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, IA, USA
| | - Diane C. Bassham
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, IA, USA
- CONTACT Diane C. Bassham Department of Genetics, Development and Cell Biology, 1035B Roy J. Carver Co-Laboratory, 1111 WOI Road, Iowa State University, Ames, Iowa 50011-3650, USA
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47
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Üstün S, Hafrén A, Hofius D. Autophagy as a mediator of life and death in plants. CURRENT OPINION IN PLANT BIOLOGY 2017; 40:122-130. [PMID: 28946008 DOI: 10.1016/j.pbi.2017.08.011] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 08/14/2017] [Accepted: 08/16/2017] [Indexed: 05/20/2023]
Abstract
Autophagy is a major pathway for degradation and recycling of cytoplasmic material, including individual proteins, aggregates, and entire organelles. Autophagic processes serve mainly survival functions in cellular homeostasis, stress adaptation and immune responses but can also have death-promoting activities in different eukaryotic organisms. In plants, the role of autophagy in the regulation of programmed cell death (PCD) remained elusive and a subject of debate. More recent evidence, however, has resulted in the consensus that autophagy can either promote or restrict different forms of PCD. Here, we present latest advances in understanding the molecular mechanisms and functions of plant autophagy and discuss their implications for life and death decisions in the context of developmental and pathogen-induced PCD.
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Affiliation(s)
- Suayib Üstün
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences (SLU) and Linnean Center for Plant Biology, SE-75007 Uppsala, Sweden
| | - Anders Hafrén
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences (SLU) and Linnean Center for Plant Biology, SE-75007 Uppsala, Sweden
| | - Daniel Hofius
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences (SLU) and Linnean Center for Plant Biology, SE-75007 Uppsala, Sweden.
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48
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Bassham DC, MacIntosh GC. Degradation of cytosolic ribosomes by autophagy-related pathways. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2017; 262:169-174. [PMID: 28716412 DOI: 10.1016/j.plantsci.2017.05.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Revised: 05/08/2017] [Accepted: 05/13/2017] [Indexed: 05/08/2023]
Abstract
Ribosomes are essential molecular machines that require a large cellular investment, yet the mechanisms of their turnover are not well understood in any eukaryotic organism. Recent advances in Arabidopsis suggest that plants utilize selective mechanisms to transport rRNA or ribosomes to the vacuole, where rRNA is degraded and the breakdown products recycled to maintain cellular homeostasis. This review focuses on known mechanisms of rRNA turnover and explores unanswered questions on the specificity and pathways of ribosome turnover and the role of this process in maintenance of cellular homeostasis.
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Affiliation(s)
- Diane C Bassham
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, IA 50011, USA.
| | - Gustavo C MacIntosh
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA 50011, USA.
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49
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Soto-Burgos J, Bassham DC. SnRK1 activates autophagy via the TOR signaling pathway in Arabidopsis thaliana. PLoS One 2017; 12:e0182591. [PMID: 28783755 PMCID: PMC5544219 DOI: 10.1371/journal.pone.0182591] [Citation(s) in RCA: 124] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Accepted: 07/20/2017] [Indexed: 12/26/2022] Open
Abstract
Autophagy is a degradation process in which cells break down and recycle their cytoplasmic contents when subjected to environmental stress or during cellular remodeling. The Arabidopsis thaliana SnRK1 complex is a protein kinase that senses changes in energy levels and triggers downstream responses to enable survival. Its mammalian ortholog, AMPK, and yeast ortholog, Snf-1, activate autophagy in response to low energy conditions. We therefore hypothesized that SnRK1 may play a role in the regulation of autophagy in response to nutrient or energy deficiency in Arabidopsis. To test this hypothesis, we determined the effect of overexpression or knockout of the SnRK1 catalytic subunit KIN10 on autophagy activation by abiotic stresses, including nutrient deficiency, salt, osmotic, oxidative, and ER stress. While wild-type plants had low basal autophagy activity in control conditions, KIN10 overexpression lines had increased autophagy under these conditions, indicating activation of autophagy by SnRK1. A kin10 mutant had a basal level of autophagy under control conditions similar to wild-type plants, but activation of autophagy by most abiotic stresses was blocked, indicating that SnRK1 is required for autophagy induction by a wide variety of stress conditions. In mammals, TOR is a negative regulator of autophagy, and AMPK acts to activate autophagy both upstream of TOR, by inhibiting its activity, and in a parallel pathway. Inhibition of Arabidopsis TOR leads to activation of autophagy; inhibition of SnRK1 did not block this activation. Furthermore, an increase in SnRK1 activity was unable to induce autophagy when TOR was also activated. These results demonstrate that SnRK1 acts upstream of TOR in the activation of autophagy in Arabidopsis.
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Affiliation(s)
- Junmarie Soto-Burgos
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, Iowa, United States of America
| | - Diane C. Bassham
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, Iowa, United States of America
- Plant Sciences Institute, Iowa State University, Ames, Iowa, United States of America
- * E-mail:
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50
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Hofius D, Li L, Hafrén A, Coll NS. Autophagy as an emerging arena for plant-pathogen interactions. CURRENT OPINION IN PLANT BIOLOGY 2017; 38:117-123. [PMID: 28545004 DOI: 10.1016/j.pbi.2017.04.017] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 04/25/2017] [Indexed: 05/20/2023]
Abstract
Autophagy is a highly conserved degradation and recycling process that controls cellular homeostasis, stress adaptation, and programmed cell death in eukaryotes. Emerging evidence indicates that autophagy is a key regulator of plant innate immunity and contributes with both pro-death and pro-survival functions to antimicrobial defences, depending on the pathogenic lifestyle. In turn, several pathogens have co-opted and evolved strategies to manipulate host autophagy pathways to the benefit of infection, while some eukaryotic microbes require their own autophagy machinery for successful pathogenesis. In this review, we present and discuss recent advances that exemplify the important role of pro- and antimicrobial autophagy in plant-pathogen interactions.
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Affiliation(s)
- Daniel Hofius
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center of Plant Biology, SE-75007 Uppsala, Sweden.
| | - Liang Li
- Centre for Research in Agricultural Genomics (CSIC-IRTA-UAB-UB), Bellaterra-Cerdanyola del Valles, 08193 Catalonia, Spain
| | - Anders Hafrén
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center of Plant Biology, SE-75007 Uppsala, Sweden
| | - Nuria S Coll
- Centre for Research in Agricultural Genomics (CSIC-IRTA-UAB-UB), Bellaterra-Cerdanyola del Valles, 08193 Catalonia, Spain.
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