1
|
Lan HJ, Ran J, Wang WX, Zhang L, Wu NN, Zhao YT, Huang MJ, Ni M, Liu F, Cheng N, Nakata PA, Pan J, Whitham SA, Baker BJ, Liu JZ. Clathrin light chains negatively regulate plant immunity by hijacking the autophagy pathway. PLANT COMMUNICATIONS 2024; 5:100937. [PMID: 38693694 DOI: 10.1016/j.xplc.2024.100937] [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: 12/17/2023] [Revised: 02/02/2024] [Accepted: 04/28/2024] [Indexed: 05/03/2024]
Abstract
The crosstalk between clathrin-mediated endocytosis (CME) and the autophagy pathway has been reported in mammals; however, the interconnection of CME with autophagy has not been established in plants. Here, we report that the Arabidopsis CLATHRIN LIGHT CHAIN (CLC) subunit 2 and 3 double mutant, clc2-1 clc3-1, phenocopies Arabidopsis AUTOPHAGY-RELATED GENE (ATG) mutants in both autoimmunity and nutrient sensitivity. Accordingly, the autophagy pathway is significantly compromised in the clc2-1 clc3-1 mutant. Interestingly, multiple assays demonstrate that CLC2 directly interacts with ATG8h/ATG8i in a domain-specific manner. As expected, both GFP-ATG8h/GFP-ATG8i and CLC2-GFP are subjected to autophagic degradation, and degradation of GFP-ATG8h is significantly reduced in the clc2-1 clc3-1 mutant. Notably, simultaneous knockout of ATG8h and ATG8i by CRISPR-Cas9 results in enhanced resistance against Golovinomyces cichoracearum, supporting the functional relevance of the CLC2-ATG8h/8i interactions. In conclusion, our results reveal a link between the function of CLCs and the autophagy pathway in Arabidopsis.
Collapse
Affiliation(s)
- Hu-Jiao Lan
- Zhejiang Provincial Key Laboratory of Biotechnology on Specialty Economic Plants, Zhejiang Normal University, Jinhua 321004, China
| | - Jie Ran
- Zhejiang Provincial Key Laboratory of Biotechnology on Specialty Economic Plants, Zhejiang Normal University, Jinhua 321004, China
| | - Wen-Xu Wang
- Zhejiang Provincial Key Laboratory of Biotechnology on Specialty Economic Plants, Zhejiang Normal University, Jinhua 321004, China
| | - Lei Zhang
- Zhejiang Provincial Key Laboratory of Biotechnology on Specialty Economic Plants, Zhejiang Normal University, Jinhua 321004, China
| | - Ni-Ni Wu
- Zhejiang Provincial Key Laboratory of Biotechnology on Specialty Economic Plants, Zhejiang Normal University, Jinhua 321004, China
| | - Ya-Ting Zhao
- Zhejiang Provincial Key Laboratory of Biotechnology on Specialty Economic Plants, Zhejiang Normal University, Jinhua 321004, China
| | - Min-Jun Huang
- Zhejiang Provincial Key Laboratory of Biotechnology on Specialty Economic Plants, Zhejiang Normal University, Jinhua 321004, China
| | - Min Ni
- Zhejiang Provincial Key Laboratory of Biotechnology on Specialty Economic Plants, Zhejiang Normal University, Jinhua 321004, China
| | - Fen Liu
- Lushan Botanical Garden, Chinese Academy of Sciences, Jiujiang 332000, China
| | - Ninghui Cheng
- U.S. Department of Agriculture-Agricultural Research Service, Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Paul A Nakata
- U.S. Department of Agriculture-Agricultural Research Service, Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Jianwei Pan
- College of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Steven A Whitham
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA 50011, USA
| | - Barbara J Baker
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Plant Gene Expression Center, U.S. Department of Agriculture-Agricultural Research Service, Albany, CA 94706, USA
| | - Jian-Zhong Liu
- Zhejiang Provincial Key Laboratory of Biotechnology on Specialty Economic Plants, Zhejiang Normal University, Jinhua 321004, China; Institute of Plant Genetics and Developmental Biology, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, China.
| |
Collapse
|
2
|
Chen X, He Y, Wu Z, Lu X, Yin Z, Zhao L, Huang H, Meng Y, Fan Y, Guo L, Wang D, Wang J, Wang S, Chen C, Wang X, Ye W. Systematic analysis and expression of Gossypium ATG8 family reveals the roles of GhATG8f responding to salt stress in cotton. PLANT CELL REPORTS 2024; 43:58. [PMID: 38321189 DOI: 10.1007/s00299-023-03137-z] [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: 07/09/2023] [Accepted: 12/29/2023] [Indexed: 02/08/2024]
Abstract
KEY MESSAGE Comprehensive analysis of Gossypium ATG8 family indicates that GhATG8f could improve salt tolerance of cotton by increasing SOD, POD and CAT activity and proline accumulation. In plants, autophagy is regulated by several genes that play important roles in initiating and controlling the process. ATG8, functioning as a protein similar to ubiquitin, is involved in crucial tasks throughout the autophagosome formation process. In this research, we conducted an extensive and all-encompassing investigation of 64 ATG8 genes across four varieties of cotton. According to the subcellular localization prediction results, 49 genes were found in the cytoplasm, 6 genes in the chloroplast, 1 gene in the peroxisome, 5 genes in the nucleus, and 3 genes in the extracellular region. Phylogenetic analysis categorized a total of 5 subfamilies containing sixty-four ATG8 genes. The expression of the majority of GhATG8 genes was induced by salt, drought, cold, and heat stresses, as revealed by RNA-seq and real-time PCR. Analysis of cis-elements in the promoters of GhATG8 genes revealed the predominant presence of responsive elements for plant hormones and abiotic stress, suggesting that GhATG8 genes might have significant functions in abiotic stress response. Furthermore, we additionally performed a gene interaction network analysis for the GhATG8 proteins. The salt stress resistance of cotton was reduced due to the downregulation of GhATG8f expression, resulting in decreased activity of CAT, SOD, and POD enzymes, as well as decreased fresh weight and proline accumulation. In summary, our research is the initial exploration of ATG8 gene components in cotton, providing a basis for future investigations into the regulatory mechanisms of ATG8 genes in autophagy and their response to abiotic stress.
Collapse
Affiliation(s)
- Xiugui Chen
- Institute of Cotton Research of Chinese Academy of Agricultural Sciences/Zhengzhou Research Base, National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Anyang, 455000, Henan, China
| | - Yunxin He
- Hunan Institute of Cotton Science, Changde, 415101, Hunan, China
| | - Zhe Wu
- Institute of Coastal Agriculture, Hebei Academy of Agriculture and Forestry Sciences, Tangshan, 063299, Hebei, China
| | - Xuke Lu
- Institute of Cotton Research of Chinese Academy of Agricultural Sciences/Zhengzhou Research Base, National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Anyang, 455000, Henan, China
| | - Zujun Yin
- Institute of Cotton Research of Chinese Academy of Agricultural Sciences/Zhengzhou Research Base, National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Anyang, 455000, Henan, China
| | - Lanjie Zhao
- Institute of Cotton Research of Chinese Academy of Agricultural Sciences/Zhengzhou Research Base, National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Anyang, 455000, Henan, China
| | - Hui Huang
- Institute of Cotton Research of Chinese Academy of Agricultural Sciences/Zhengzhou Research Base, National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Anyang, 455000, Henan, China
| | - Yuan Meng
- Institute of Cotton Research of Chinese Academy of Agricultural Sciences/Zhengzhou Research Base, National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Anyang, 455000, Henan, China
| | - Yapeng Fan
- Institute of Cotton Research of Chinese Academy of Agricultural Sciences/Zhengzhou Research Base, National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Anyang, 455000, Henan, China
| | - Lixue Guo
- Institute of Cotton Research of Chinese Academy of Agricultural Sciences/Zhengzhou Research Base, National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Anyang, 455000, Henan, China
| | - Delong Wang
- Institute of Cotton Research of Chinese Academy of Agricultural Sciences/Zhengzhou Research Base, National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Anyang, 455000, Henan, China
| | - Junjuan Wang
- Institute of Cotton Research of Chinese Academy of Agricultural Sciences/Zhengzhou Research Base, National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Anyang, 455000, Henan, China
| | - Shuai Wang
- Institute of Cotton Research of Chinese Academy of Agricultural Sciences/Zhengzhou Research Base, National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Anyang, 455000, Henan, China
| | - Chao Chen
- Institute of Cotton Research of Chinese Academy of Agricultural Sciences/Zhengzhou Research Base, National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Anyang, 455000, Henan, China
| | - Xiupin Wang
- Institute of Coastal Agriculture, Hebei Academy of Agriculture and Forestry Sciences, Tangshan, 063299, Hebei, China.
| | - Wuwei Ye
- Institute of Cotton Research of Chinese Academy of Agricultural Sciences/Zhengzhou Research Base, National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Anyang, 455000, Henan, China.
| |
Collapse
|
3
|
Zeng Y, Liang Z, Liu Z, Li B, Cui Y, Gao C, Shen J, Wang X, Zhao Q, Zhuang X, Erdmann PS, Wong KB, Jiang L. Recent advances in plant endomembrane research and new microscopical techniques. THE NEW PHYTOLOGIST 2023; 240:41-60. [PMID: 37507353 DOI: 10.1111/nph.19134] [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: 05/12/2023] [Accepted: 06/19/2023] [Indexed: 07/30/2023]
Abstract
The endomembrane system consists of various membrane-bound organelles including the endoplasmic reticulum (ER), Golgi apparatus, trans-Golgi network (TGN), endosomes, and the lysosome/vacuole. Membrane trafficking between distinct compartments is mainly achieved by vesicular transport. As the endomembrane compartments and the machineries regulating the membrane trafficking are largely conserved across all eukaryotes, our current knowledge on organelle biogenesis and endomembrane trafficking in plants has mainly been shaped by corresponding studies in mammals and yeast. However, unique perspectives have emerged from plant cell biology research through the characterization of plant-specific regulators as well as the development and application of the state-of-the-art microscopical techniques. In this review, we summarize our current knowledge on the plant endomembrane system, with a focus on several distinct pathways: ER-to-Golgi transport, protein sorting at the TGN, endosomal sorting on multivesicular bodies, vacuolar trafficking/vacuole biogenesis, and the autophagy pathway. We also give an update on advanced imaging techniques for the plant cell biology research.
Collapse
Affiliation(s)
- Yonglun Zeng
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Zizhen Liang
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Zhiqi Liu
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Baiying Li
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Yong Cui
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, 361102, China
| | - Caiji Gao
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Jinbo Shen
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou, 311300, China
| | - Xiangfeng Wang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Qiong Zhao
- School of Life Sciences, East China Normal University, Shanghai, 200062, China
| | - Xiaohong Zhuang
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Philipp S Erdmann
- Human Technopole, Viale Rita Levi-Montalcini, 1, Milan, I-20157, Italy
| | - Kam-Bo Wong
- Centre for Protein Science and Crystallography, School of Life Sciences, The Chinese University of Hong Kong (CUHK), Shatin, Hong Kong, China
| | - Liwen Jiang
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
- The CUHK Shenzhen Research Institute, Shenzhen, 518057, China
- Institute of Plant Molecular Biology and Agricultural Biotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| |
Collapse
|
4
|
Wan C, Zhang H, Cheng H, Sowden RG, Cai W, Jarvis RP, Ling Q. Selective autophagy regulates chloroplast protein import and promotes plant stress tolerance. EMBO J 2023; 42:e112534. [PMID: 37248861 PMCID: PMC10350842 DOI: 10.15252/embj.2022112534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 03/26/2023] [Accepted: 05/09/2023] [Indexed: 05/31/2023] Open
Abstract
Chloroplasts are plant organelles responsible for photosynthesis and environmental sensing. Most chloroplast proteins are imported from the cytosol through the translocon at the outer envelope membrane of chloroplasts (TOC). Previous work has shown that TOC components are regulated by the ubiquitin-proteasome system (UPS) to control the chloroplast proteome, which is crucial for the organelle's function and plant development. Here, we demonstrate that the TOC apparatus is also subject to K63-linked polyubiquitination and regulation by selective autophagy, potentially promoting plant stress tolerance. We identify NBR1 as a selective autophagy adaptor targeting TOC components, and mediating their relocation into vacuoles for autophagic degradation. Such selective autophagy is shown to control TOC protein levels and chloroplast protein import and to influence photosynthetic activity as well as tolerance to UV-B irradiation and heat stress in Arabidopsis plants. These findings uncover the vital role of selective autophagy in the proteolytic regulation of specific chloroplast proteins, and how dynamic control of chloroplast protein import is critically important for plants to cope with challenging environments.
Collapse
Affiliation(s)
- Chen Wan
- National Key Laboratory of Plant Molecular Genetics, CAS Centre for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
| | - Hui Zhang
- National Key Laboratory of Plant Molecular Genetics, CAS Centre for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghaiChina
| | - Hongying Cheng
- National Key Laboratory of Plant Molecular Genetics, CAS Centre for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
| | - Robert G Sowden
- Department of Plant Sciences and Section of Molecular Plant Biology (Department of Biology)University of OxfordOxfordUK
| | - Wenjuan Cai
- Core Facility Center, CAS Centre for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghaiChina
| | - R Paul Jarvis
- Department of Plant Sciences and Section of Molecular Plant Biology (Department of Biology)University of OxfordOxfordUK
| | - Qihua Ling
- National Key Laboratory of Plant Molecular Genetics, CAS Centre for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
- CAS‐JIC Center of Excellence for Plant and Microbial Sciences (CEPAMS), Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghaiChina
| |
Collapse
|
5
|
Autophagic degradation of membrane-bound organelles in plants. Biosci Rep 2023; 43:232379. [PMID: 36562332 PMCID: PMC9842949 DOI: 10.1042/bsr20221204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 12/19/2022] [Accepted: 12/22/2022] [Indexed: 12/24/2022] Open
Abstract
Eukaryotic cells have evolved membrane-bound organelles, including the endoplasmic reticulum (ER), Golgi, mitochondria, peroxisomes, chloroplasts (in plants and green algae) and lysosomes/vacuoles, for specialized functions. Organelle quality control and their proper interactions are crucial both for normal cell homeostasis and function and for environmental adaption. Dynamic turnover of organelles is tightly controlled, with autophagy playing an essential role. Autophagy is a programmed process for efficient clearing of unwanted or damaged macromolecules or organelles, transporting them to vacuoles for degradation and recycling and thereby enhancing plant environmental plasticity. The specific autophagic engulfment of organelles requires activation of a selective autophagy pathway, recognition of the organelle by a receptor, and selective incorporation of the organelle into autophagosomes. While some of the autophagy machinery and mechanisms for autophagic removal of organelles is conserved across eukaryotes, plants have also developed unique mechanisms and machinery for these pathways. In this review, we discuss recent progress in understanding autophagy regulation in plants, with a focus on autophagic degradation of membrane-bound organelles. We also raise some important outstanding questions to be addressed in the future.
Collapse
|
6
|
Coordinative regulation of ERAD and selective autophagy in plants. Essays Biochem 2022; 66:179-188. [PMID: 35612379 DOI: 10.1042/ebc20210099] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 05/02/2022] [Accepted: 05/06/2022] [Indexed: 12/30/2022]
Abstract
Endoplasmic reticulum-associated degradation (ERAD) plays important roles in plant development, hormone signaling, and plant-environment stress interactions by promoting the clearance of certain proteins or soluble misfolded proteins through the ubiquitin-proteasome system. Selective autophagy is involved in the autophagic degradation of protein aggregates mediated by specific selective autophagy receptors. These two major degradation routes co-operate with each other to relieve the cytotoxicity caused by ER stress. In this review, we analyze ERAD and different types of autophagy, including nonselective macroautophagy and ubiquitin-dependent and ubiquitin-independent selective autophagy in plants, and specifically summarize the selective autophagy receptors characterized in plants. In addition to being a part of selective autophagy, ERAD components also serve as their cargos. Moreover, an ubiquitinated substrate can be delivered to two distinguishable degradation systems, while the underlying determinants remain elusive. These excellent findings suggest an interdependent but complicated relationship between ERAD and selective autophagy. According to this point, we propose several key issues that need to be addressed in the future.
Collapse
|
7
|
Laloum D, Magen S, Soroka Y, Avin-Wittenberg T. Exploring the Contribution of Autophagy to the Excess-Sucrose Response in Arabidopsis thaliana. Int J Mol Sci 2022; 23:ijms23073891. [PMID: 35409249 PMCID: PMC8999498 DOI: 10.3390/ijms23073891] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 03/13/2022] [Accepted: 03/29/2022] [Indexed: 01/18/2023] Open
Abstract
Autophagy is an essential intracellular eukaryotic recycling mechanism, functioning in, among others, carbon starvation. Surprisingly, although autophagy-deficient plants (atg mutants) are hypersensitive to carbon starvation, metabolic analysis revealed that they accumulate sugars under such conditions. In plants, sugars serve as both an energy source and as signaling molecules, affecting many developmental processes, including root and shoot formation. We thus set out to understand the interplay between autophagy and sucrose excess, comparing wild-type and atg mutant seedlings. The presented work showed that autophagy contributes to primary root elongation arrest under conditions of exogenous sucrose and glucose excess but not during fructose or mannitol treatment. Minor or no alterations in starch and primary metabolites were observed between atg mutants and wild-type plants, indicating that the sucrose response relates to its signaling and not its metabolic role. Extensive proteomic analysis of roots performed to further understand the mechanism found an accumulation of proteins essential for ROS reduction and auxin maintenance, which are necessary for root elongation, in atg plants under sucrose excess. The analysis also suggested mitochondrial and peroxisomal involvement in the autophagy-mediated sucrose response. This research increases our knowledge of the complex interplay between autophagy and sugar signaling in plants.
Collapse
|
8
|
Reggiori F, Molinari M. ER-phagy: mechanisms, regulation and diseases connected to the lysosomal clearance of the endoplasmic reticulum. Physiol Rev 2022; 102:1393-1448. [PMID: 35188422 PMCID: PMC9126229 DOI: 10.1152/physrev.00038.2021] [Citation(s) in RCA: 52] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
ER-phagy (reticulo-phagy) defines the degradation of portions of the endoplasmic reticulum (ER) within lysosomes or vacuoles. It is part of the self-digestion (i.e., auto-phagic) programs recycling cytoplasmic material and organelles, which rapidly mobilize metabolites in cells confronted with nutrient shortage. Moreover, selective clearance of ER subdomains participates to the control of ER size and activity during ER stress, the re-establishment of ER homeostasis after ER stress resolution and the removal of ER parts, in which aberrant and potentially cytotoxic material has been segregated. ER-phagy relies on the individual and/or concerted activation of the ER-phagy receptors, ER peripheral or integral membrane proteins that share the presence of LC3/Atg8-binding motifs in their cytosolic domains. ER-phagy involves the physical separation of portions of the ER from the bulk ER network, and their delivery to the endolysosomal/vacuolar catabolic district. This last step is accomplished by a variety of mechanisms including macro-ER-phagy (in which ER fragments are sequestered by double-membrane autophagosomes that eventually fuse with lysosomes/vacuoles), micro-ER-phagy (in which ER fragments are directly engulfed by endosomes/lysosomes/vacuoles), or direct fusion of ER-derived vesicles with lysosomes/vacuoles. ER-phagy is dysfunctional in specific human diseases and its regulators are subverted by pathogens, highlighting its crucial role for cell and organism life.
Collapse
Affiliation(s)
- Fulvio Reggiori
- Department of Biomedical Sciences of Cells & Systems, grid.4830.fUniversity of Groningen, Netherlands
| | - Maurizio Molinari
- Protein Folding and Quality Control, grid.7722.0Institute for Research in Biomedicine, Bellinzona, Switzerland
| |
Collapse
|
9
|
Liu W, Liu Z, Mo Z, Guo S, Liu Y, Xie Q. ATG8-Interacting Motif: Evolution and Function in Selective Autophagy of Targeting Biological Processes. FRONTIERS IN PLANT SCIENCE 2021; 12:783881. [PMID: 34912364 PMCID: PMC8666691 DOI: 10.3389/fpls.2021.783881] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 10/28/2021] [Indexed: 05/26/2023]
Abstract
Autophagy is an evolutionarily conserved vacuolar process functioning in the degradation of cellular components for reuse. In plants, autophagy is generally activated upon stress and its regulation is executed by numbers of AuTophaGy-related genes (ATGs), of which the ATG8 plays a dual role in both biogenesis of autophagosomes and recruitment of ATG8-interacting motif (AIM) anchored selective autophagy receptors (SARs). Such motif is either termed as AIM or ubiquitin-interacting motif (UIM), corresponding to the LC3-interacting region (LIR)/AIM docking site (LDS) or the UIM docking site (UDS) of ATG8, respectively. To date, dozens of AIM or UIM containing SARs have been characterized. However, the knowledge of these motifs is still obscured. In this review, we intend to summarize the current understanding of SAR proteins and discuss the conservation and diversification of the AIMs/UIMs, expectantly providing new insights into the evolution of them in various biological processes in plants.
Collapse
Affiliation(s)
- Wanqing Liu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou, China
- Rice Research Institute, Guangdong Academy of Agricultural Sciences/Guangdong Key Laboratory of New Technology in Rice Breeding/Guangdong Rice Engineering Laboratory, Guangzhou, China
| | - Zinan Liu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou, China
| | - Zulong Mo
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou, China
| | - Shaoying Guo
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou, China
| | - Yunfeng Liu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Life Science and Technology, Guangxi University, Nanning, China
| | - Qingjun Xie
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou, China
| |
Collapse
|
10
|
Autophagy in Plant Abiotic Stress Management. Int J Mol Sci 2021; 22:ijms22084075. [PMID: 33920817 PMCID: PMC8071135 DOI: 10.3390/ijms22084075] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 04/03/2021] [Accepted: 04/05/2021] [Indexed: 12/11/2022] Open
Abstract
Plants can be considered an open system. Throughout their life cycle, plants need to exchange material, energy and information with the outside world. To improve their survival and complete their life cycle, plants have developed sophisticated mechanisms to maintain cellular homeostasis during development and in response to environmental changes. Autophagy is an evolutionarily conserved self-degradative process that occurs ubiquitously in all eukaryotic cells and plays many physiological roles in maintaining cellular homeostasis. In recent years, an increasing number of studies have shown that autophagy can be induced not only by starvation but also as a cellular response to various abiotic stresses, including oxidative, salt, drought, cold and heat stresses. This review focuses mainly on the role of autophagy in plant abiotic stress management.
Collapse
|
11
|
Wang H, Ding Z, Gou M, Hu J, Wang Y, Wang L, Wang Y, Di T, Zhang X, Hao X, Wang X, Yang Y, Qian W. Genome-wide identification, characterization, and expression analysis of tea plant autophagy-related genes (CsARGs) demonstrates that they play diverse roles during development and under abiotic stress. BMC Genomics 2021; 22:121. [PMID: 33596831 PMCID: PMC7891152 DOI: 10.1186/s12864-021-07419-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 01/31/2021] [Indexed: 12/12/2022] Open
Abstract
Background Autophagy, meaning ‘self-eating’, is required for the degradation and recycling of cytoplasmic constituents under stressful and non-stressful conditions, which helps to maintain cellular homeostasis and delay aging and longevity in eukaryotes. To date, the functions of autophagy have been heavily studied in yeast, mammals and model plants, but few studies have focused on economically important crops, especially tea plants (Camellia sinensis). The roles played by autophagy in coping with various environmental stimuli have not been fully elucidated to date. Therefore, investigating the functions of autophagy-related genes in tea plants may help to elucidate the mechanism governing autophagy in response to stresses in woody plants. Results In this study, we identified 35 C. sinensis autophagy-related genes (CsARGs). Each CsARG is highly conserved with its homologues from other plant species, except for CsATG14. Tissue-specific expression analysis demonstrated that the abundances of CsARGs varied across different tissues, but CsATG8c/i showed a degree of tissue specificity. Under hormone and abiotic stress conditions, most CsARGs were upregulated at different time points during the treatment. In addition, the expression levels of 10 CsARGs were higher in the cold-resistant cultivar ‘Longjing43’ than in the cold-susceptible cultivar ‘Damianbai’ during the CA period; however, the expression of CsATG101 showed the opposite tendency. Conclusions We performed a comprehensive bioinformatic and physiological analysis of CsARGs in tea plants, and these results may help to establish a foundation for further research investigating the molecular mechanisms governing autophagy in tea plant growth, development and response to stress. Meanwhile, some CsARGs could serve as putative molecular markers for the breeding of cold-resistant tea plants in future research. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-021-07419-2.
Collapse
Affiliation(s)
- Huan Wang
- College of Horticulture, Qingdao Agricultural University, Qingdao, 266109, China
| | - Zhaotang Ding
- College of Horticulture, Qingdao Agricultural University, Qingdao, 266109, China
| | - Mengjie Gou
- College of Horticulture, Qingdao Agricultural University, Qingdao, 266109, China
| | - Jianhui Hu
- College of Horticulture, Qingdao Agricultural University, Qingdao, 266109, China
| | - Yu Wang
- College of Horticulture, Qingdao Agricultural University, Qingdao, 266109, China
| | - Lu Wang
- National Center for Tea Plant Improvement, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, 310008, China.,Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, Hangzhou, 310008, China
| | - Yuchun Wang
- College of Agriculture and Food Science, Zhejiang A&F University, Hangzhou, 311300, China
| | - Taimei Di
- National Center for Tea Plant Improvement, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, 310008, China.,Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, Hangzhou, 310008, China
| | - Xinfu Zhang
- College of Horticulture, Qingdao Agricultural University, Qingdao, 266109, China
| | - Xinyuan Hao
- National Center for Tea Plant Improvement, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, 310008, China.,Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, Hangzhou, 310008, China
| | - Xinchao Wang
- National Center for Tea Plant Improvement, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, 310008, China.,Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, Hangzhou, 310008, China
| | - Yajun Yang
- National Center for Tea Plant Improvement, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, 310008, China.,Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, Hangzhou, 310008, China
| | - Wenjun Qian
- College of Horticulture, Qingdao Agricultural University, Qingdao, 266109, China.
| |
Collapse
|
12
|
Wu J, Michaeli S, Picchianti L, Dagdas Y, Galili G, Peled-Zehavi H. ATI1 (ATG8-interacting protein 1) and ATI2 define a plant starvation-induced reticulophagy pathway and serve as MSBP1/MAPR5 cargo receptors. Autophagy 2021; 17:3375-3388. [PMID: 33487099 DOI: 10.1080/15548627.2021.1872886] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Reticulophagy, the selective autophagy of endoplasmic reticulum (ER) components, is known to operate in eukaryotes from yeast and unicellular algae to animals and plants. Thus far, only ER-stress induced reticulophagy was reported and analyzed in plants. In this study we characterize a reticulophagy pathway in Arabidopsis thaliana that is triggered by dark-induced starvation but not by ER stress. This pathway is defined by the previously reported ATG8-interacting proteins, ATI1 and ATI2. We further identified the ER-localized MSBP1 (Membrane Steroid Binding Protein 1) as an ATI1- and ATI2-interacting protein and an autophagy cargo, and show that ATI1 and ATI2 serve as its cargo receptors. Together, these findings expand our knowledge on plant responses during energy deprivation and highlight the role of this special type of reticulophagy in this process.Abbreviations: AGO1: ARGONAUTE 1; ATI: ATG8-Interacting Protein; BiFC: Bimolecular Fluorescence Complementation; BR: brassinosteroid; conA: concanamycin A; DMSO: dimethyl sulfoxid; DTT: dithiothreitol; ER: endoplasmic reticulum; GFP: green fluorescent protein; MAPR: Membrane-Associated Progesterone Binding Protein; MSBP: Membrane Steroid Binding Protein; SD: standard deviation; SE: standard error; TM: tunicamycin; TOR: target of rapamycin; Y2H: yeast two-hybrid.
Collapse
Affiliation(s)
- Jian Wu
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Simon Michaeli
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Lorenzo Picchianti
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna BioCenter (VBC), Vienna, Austria
| | - Yasin Dagdas
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna BioCenter (VBC), Vienna, Austria
| | - Gad Galili
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Hadas Peled-Zehavi
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| |
Collapse
|
13
|
Luo S, Li X, Zhang Y, Fu Y, Fan B, Zhu C, Chen Z. Cargo Recognition and Function of Selective Autophagy Receptors in Plants. Int J Mol Sci 2021; 22:ijms22031013. [PMID: 33498336 PMCID: PMC7864022 DOI: 10.3390/ijms22031013] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 01/18/2021] [Accepted: 01/18/2021] [Indexed: 12/16/2022] Open
Abstract
Autophagy is a major quality control system for degradation of unwanted or damaged cytoplasmic components to promote cellular homeostasis. Although non-selective bulk degradation of cytoplasm by autophagy plays a role during cellular response to nutrient deprivation, the broad roles of autophagy are primarily mediated by selective clearance of specifically targeted components. Selective autophagy relies on cargo receptors that recognize targeted components and recruit them to autophagosomes through interaction with lapidated autophagy-related protein 8 (ATG8) family proteins anchored in the membrane of the forming autophagosomes. In mammals and yeast, a large collection of selective autophagy receptors have been identified that mediate the selective autophagic degradation of organelles, aggregation-prone misfolded proteins and other unwanted or nonnative proteins. A substantial number of selective autophagy receptors have also been identified and functionally characterized in plants. Some of the autophagy receptors in plants are evolutionarily conserved with homologs in other types of organisms, while a majority of them are plant-specific or plant species-specific. Plant selective autophagy receptors mediate autophagic degradation of not only misfolded, nonactive and otherwise unwanted cellular components but also regulatory and signaling factors and play critical roles in plant responses to a broad spectrum of biotic and abiotic stresses. In this review, we summarize the research on selective autophagy in plants, with an emphasis on the cargo recognition and the biological functions of plant selective autophagy receptors.
Collapse
Affiliation(s)
- Shuwei Luo
- College of Life Sciences, China Jiliang University, Hangzhou 310018, China; (S.L.); (X.L.); (Y.F.)
| | - Xifeng Li
- College of Life Sciences, China Jiliang University, Hangzhou 310018, China; (S.L.); (X.L.); (Y.F.)
| | - Yan Zhang
- Department of Landscape and Horticulture, Ecology College, Lishui University, Lishui 323000, China;
- Department of Botany and Plant Pathology, Purdue Center for Plant Biology, Purdue University, West Lafayette, IN 47907-2054, USA;
| | - Yunting Fu
- College of Life Sciences, China Jiliang University, Hangzhou 310018, China; (S.L.); (X.L.); (Y.F.)
| | - Baofang Fan
- Department of Botany and Plant Pathology, Purdue Center for Plant Biology, Purdue University, West Lafayette, IN 47907-2054, USA;
| | - Cheng Zhu
- College of Life Sciences, China Jiliang University, Hangzhou 310018, China; (S.L.); (X.L.); (Y.F.)
- Correspondence: (C.Z.); (Z.C.); Tel.: +86-571-8683-6090 (C.Z.); +1-765-494-4657 (Z.C.)
| | - Zhixiang Chen
- College of Life Sciences, China Jiliang University, Hangzhou 310018, China; (S.L.); (X.L.); (Y.F.)
- Department of Botany and Plant Pathology, Purdue Center for Plant Biology, Purdue University, West Lafayette, IN 47907-2054, USA;
- Correspondence: (C.Z.); (Z.C.); Tel.: +86-571-8683-6090 (C.Z.); +1-765-494-4657 (Z.C.)
| |
Collapse
|
14
|
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.
Collapse
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
| |
Collapse
|
15
|
Broad and Complex Roles of NBR1-Mediated Selective Autophagy in Plant Stress Responses. Cells 2020; 9:cells9122562. [PMID: 33266087 PMCID: PMC7760648 DOI: 10.3390/cells9122562] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Revised: 11/27/2020] [Accepted: 11/27/2020] [Indexed: 02/07/2023] Open
Abstract
Selective autophagy is a highly regulated degradation pathway for the removal of specific damaged or unwanted cellular components and organelles such as protein aggregates. Cargo selectivity in selective autophagy relies on the action of cargo receptors and adaptors. In mammalian cells, two structurally related proteins p62 and NBR1 act as cargo receptors for selective autophagy of ubiquitinated proteins including aggregation-prone proteins in aggrephagy. Plant NBR1 is the structural and functional homolog of mammalian p62 and NBR1. Since its first reports almost ten years ago, plant NBR1 has been well established to function as a cargo receptor for selective autophagy of stress-induced protein aggregates and play an important role in plant responses to a broad spectrum of stress conditions including heat, salt and drought. Over the past several years, important progress has been made in the discovery of specific cargo proteins of plant NBR1 and their roles in the regulation of plant heat stress memory, plant-viral interaction and special protein secretion. There is also new evidence for a possible role of NBR1 in stress-induced pexophagy, sulfur nutrient responses and abscisic acid signaling. In this review, we summarize these progresses and discuss the potential significance of NBR1-mediated selective autophagy in broad plant responses to both biotic and abiotic stresses.
Collapse
|
16
|
Bedu M, Marmagne A, Masclaux-Daubresse C, Chardon F. Transcriptional Plasticity of Autophagy-Related Genes Correlates with the Genetic Response to Nitrate Starvation in Arabidopsis Thaliana. Cells 2020; 9:E1021. [PMID: 32326055 PMCID: PMC7226452 DOI: 10.3390/cells9041021] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 04/16/2020] [Accepted: 04/16/2020] [Indexed: 01/22/2023] Open
Abstract
In eukaryotes, autophagy, a catabolic mechanism for macromolecule and protein recycling, allows the maintenance of amino acid pools and nutrient remobilization. For a better understanding of the relationship between autophagy and nitrogen metabolism, we studied the transcriptional plasticity of autophagy genes (ATG) in nine Arabidopsis accessions grown under normal and nitrate starvation conditions. The status of the N metabolism in accessions was monitored by measuring the relative expression of 11 genes related to N metabolism in rosette leaves. The transcriptional variation of the genes coding for enzymes involved in ammonium assimilation characterize the genetic diversity of the response to nitrate starvation. Starvation enhanced the expression of most of the autophagy genes tested, suggesting a control of autophagy at transcriptomic level by nitrogen. The diversity of the gene responses among natural accessions revealed the genetic variation existing for autophagy independently of the nutritive condition, and the degree of response to nitrate starvation. We showed here that the genetic diversity of the expression of N metabolism genes correlates with that of the ATG genes in the two nutritive conditions, suggesting that the basal autophagy activity is part of the integral response of the N metabolism to nitrate availability.
Collapse
Affiliation(s)
- Magali Bedu
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000 Versailles, France; (M.B.); (A.M.); (C.M.-D.)
- Bureau International des Poids et Mesures (BIPM), Pavillon de Breteuil, F-92312 Sèvres, France
| | - Anne Marmagne
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000 Versailles, France; (M.B.); (A.M.); (C.M.-D.)
| | - Céline Masclaux-Daubresse
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000 Versailles, France; (M.B.); (A.M.); (C.M.-D.)
| | - Fabien Chardon
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000 Versailles, France; (M.B.); (A.M.); (C.M.-D.)
| |
Collapse
|
17
|
Liao CY, Bassham DC. Combating stress: the interplay between hormone signaling and autophagy in plants. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:1723-1733. [PMID: 31725881 PMCID: PMC7067298 DOI: 10.1093/jxb/erz515] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 11/13/2019] [Indexed: 05/18/2023]
Abstract
Autophagy is a conserved recycling process in which cellular components are delivered to and degraded in the vacuole/lysosome for reuse. In plants, it assists in responding to dynamic environmental conditions and maintaining metabolite homeostasis under normal or stress conditions. Under stress, autophagy is activated to remove damaged components and to recycle nutrients for survival, and the energy sensor kinases target of rapamycin (TOR) and SNF-related kinase 1 (SnRK1) are key to this activation. Here, we discuss accumulating evidence that hormone signaling plays critical roles in regulating autophagy and plant stress responses, although the molecular mechanisms by which this occurs are often not clear. Several hormones have been shown to regulate TOR activity during stress, in turn controlling autophagy. Hormone signaling can also regulate autophagy gene expression, while, reciprocally, autophagy can regulate hormone synthesis and signaling pathways. We highlight how the interplay between major energy sensors, plant hormones, and autophagy under abiotic and biotic stress conditions can assist in plant stress tolerance.
Collapse
Affiliation(s)
- Ching-Yi Liao
- 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
- Correspondence:
| |
Collapse
|
18
|
Zienkiewicz A, Zienkiewicz K, Poliner E, Pulman JA, Du ZY, Stefano G, Tsai CH, Horn P, Feussner I, Farre EM, Childs KL, Brandizzi F, Benning C. The Microalga Nannochloropsis during Transition from Quiescence to Autotrophy in Response to Nitrogen Availability. PLANT PHYSIOLOGY 2020; 182:819-839. [PMID: 31740503 PMCID: PMC6997683 DOI: 10.1104/pp.19.00854] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 11/04/2019] [Indexed: 05/03/2023]
Abstract
The marine microalgae Nannochloropsis oceanica (CCMP1779) is a prolific producer of oil and is considered a viable and sustainable resource for biofuel feedstocks. Nitrogen (N) availability has a strong impact on the physiological status and metabolism of microalgal cells, but the exact nature of this response is poorly understood. To fill this gap we performed transcriptomic profiling combined with cellular and molecular analyses of N. oceanica CCMP1779 during the transition from quiescence to autotrophy. N deprivation-induced quiescence was accompanied by a strong reorganization of the photosynthetic apparatus and changes in the lipid homeostasis, leading to accumulation of triacylglycerol. Cell cycle activation and re-establishment of photosynthetic activity observed in response to resupply of the growth medium with N were accompanied by a rapid degradation of triacylglycerol stored in lipid droplets (LDs). Besides observing LD translocation into vacuoles, we also provide evidence for direct interaction between the LD surface protein (NoLDSP) and AUTOPHAGY-RELATED8 (NoATG8) protein and show a role of microlipophagy in LD turnover in N. oceanica CCMP1779. This knowledge is crucial not only for understanding the fundamental mechanisms controlling the cellular energy homeostasis in microalgal cells but also for development of efficient strategies to achieve higher algal biomass and better microalgal lipid productivity.
Collapse
Affiliation(s)
- Agnieszka Zienkiewicz
- Michigan State University-United States Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824
- Great Lakes Bioenergy Center, Michigan State University, East Lansing, Michigan 48824
- Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University, 87-100 Toruń, Poland
| | - Krzysztof Zienkiewicz
- Michigan State University-United States Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824
- Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University, 87-100 Toruń, Poland
- Department of Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences, University of Goettingen, 37073 Goettingen, Germany
| | - Eric Poliner
- Michigan State University-United States Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824
- Cell and Molecular Biology Program, Michigan State University, East Lansing, Michigan 48824
- Department of Plant Biology, Michigan State University, East Lansing, Michigan 48824
| | - Jane A Pulman
- Department of Plant Biology, Michigan State University, East Lansing, Michigan 48824
- Center for Genomics-Enabled Plant Science, Michigan State University, East Lansing, Michigan 48824
| | - Zhi-Yan Du
- Michigan State University-United States Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824
| | - Giovanni Stefano
- Michigan State University-United States Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824
| | - Chia-Hong Tsai
- Michigan State University-United States Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824
- Department of Plant Biology, Michigan State University, East Lansing, Michigan 48824
| | - Patrick Horn
- Michigan State University-United States Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824
| | - Ivo Feussner
- Department of Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences, University of Goettingen, 37073 Goettingen, Germany
- Department of Plant Biochemistry, Goettingen Center for Molecular Biosciences (GZMB), University of Goettingen, 37073 Goettingen, Germany
- Department of Plant Biochemistry, International Center for Advanced Studies of Energy Conversion (ICASEC), University of Goettingen, 37073 Goettingen, Germany
| | - Eva M Farre
- Department of Plant Biology, Michigan State University, East Lansing, Michigan 48824
| | - Kevin L Childs
- Department of Plant Biology, Michigan State University, East Lansing, Michigan 48824
- Center for Genomics-Enabled Plant Science, Michigan State University, East Lansing, Michigan 48824
| | - Federica Brandizzi
- Michigan State University-United States Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824
| | - Christoph Benning
- Michigan State University-United States Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824
- Great Lakes Bioenergy Center, Michigan State University, East Lansing, Michigan 48824
- Department of Plant Biology, Michigan State University, East Lansing, Michigan 48824
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824
| |
Collapse
|
19
|
Su T, Li X, Yang M, Shao Q, Zhao Y, Ma C, Wang P. Autophagy: An Intracellular Degradation Pathway Regulating Plant Survival and Stress Response. FRONTIERS IN PLANT SCIENCE 2020; 11:164. [PMID: 32184795 PMCID: PMC7058704 DOI: 10.3389/fpls.2020.00164] [Citation(s) in RCA: 98] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 02/03/2020] [Indexed: 05/18/2023]
Abstract
Autophagy is an intracellular process that facilitates the bulk degradation of cytoplasmic materials by the vacuole or lysosome in eukaryotes. This conserved process is achieved through the coordination of different autophagy-related genes (ATGs). Autophagy is essential for recycling cytoplasmic material and eliminating damaged or dysfunctional cell constituents, such as proteins, aggregates or even entire organelles. Plant autophagy is necessary for maintaining cellular homeostasis under normal conditions and is upregulated during abiotic and biotic stress to prolong cell life. In this review, we present recent advances on our understanding of the molecular mechanisms of autophagy in plants and how autophagy contributes to plant development and plants' adaptation to the environment.
Collapse
Affiliation(s)
| | | | | | | | | | - Changle Ma
- *Correspondence: Changle Ma, ; Pingping Wang,
| | | |
Collapse
|
20
|
Autophagy in Plant: A New Orchestrator in the Regulation of the Phytohormones Homeostasis. Int J Mol Sci 2019; 20:ijms20122900. [PMID: 31197094 PMCID: PMC6627538 DOI: 10.3390/ijms20122900] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 06/07/2019] [Accepted: 06/13/2019] [Indexed: 12/15/2022] Open
Abstract
Autophagy is a highly evolutionarily-conserved catabolic process facilitating the development and survival of organisms which have undergone favorable and/or stressful conditions, in particular the plant. Accumulating evidence has implicated that autophagy is involved in growth and development, as well as responses to various stresses in plant. Similarly, phytohormones also play a pivotal role in the response to various stresses in addition to the plant growth and development. However, the relationship between autophagy and phytohormones still remains poorly understood. Here, we review advances in the crosstalk between them upon various environmental stimuli. We also discuss how autophagy coordinates the phytohormones to regulate plant growth and development. We propose that unraveling the regulatory role(s) of autophagy in modulating the homeostasis of phytohormones would benefit crop breeding and improvement under variable environments, in particular under suboptimal conditions.
Collapse
|
21
|
Tornkvist A, Liu C, Moschou PN. Proteolysis and nitrogen: emerging insights. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:2009-2019. [PMID: 30715465 DOI: 10.1093/jxb/erz024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 01/10/2019] [Indexed: 05/07/2023]
Abstract
Nitrogen (N) is a core component of fertilizers used in modern agriculture to increase yields and thus to help feed a growing global population. However, this comes at a cost to the environment, through run-off of excess N as a result of poor N-use efficiency (NUE) by crops. An obvious remedy to this problem would therefore be the improvement of NUE, which requires advancing our understanding on N homeostasis, sensing, and uptake. Proteolytic pathways are linked to N homeostasis as they recycle proteins that contain N and carbon; however, emerging data suggest that their functions extend beyond this simple recycling. Here, we highlight roles of proteolytic pathways in non-symbiotic and symbiotic N uptake and in systemic N sensing. We also offer a novel view in which we suggest that proteolytic pathways have roles in N homeostasis that differ from their accepted function in recycling.
Collapse
Affiliation(s)
- Anna Tornkvist
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
| | - Chen Liu
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
| | - Panagiotis N Moschou
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
- Department of Biology, University of Crete, Heraklion, Greece
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology - Hellas, Heraklion, Greece
| |
Collapse
|
22
|
Li H, Hu P, Wang Y, Pan Y, Liu G. Enhancing the production of cephalosporin C through modulating the autophagic process of Acremonium chrysogenum. Microb Cell Fact 2018; 17:175. [PMID: 30424777 PMCID: PMC6233533 DOI: 10.1186/s12934-018-1021-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 11/01/2018] [Indexed: 11/12/2022] Open
Abstract
Background Autophagy is used for degradation of cellular components and nutrient recycling. Atg8 is one of the core proteins in autophagy and used as a marker for autophagic detection. However, the autophagy of filamentous fungi is poorly understood compared with that of Saccharomyces cerevisiae. Our previous study revealed that disruption of the autophagy related gene Acatg1 significantly enhanced cephalosporin C yield through reducing degradation of cephalosporin biosynthetic proteins in Acremonium chrysogenum, suggesting that modulation of autophagic process is one promising way to increase antibiotic production in A. chrysogenum. Results In this study, a S. cerevisiae ATG8 homologue gene Acatg8 was identified from A. chrysogenum. Acatg8 could complement the ATG8 mutation in S. cerevisiae, indicating that Acatg8 is a functional homologue of ATG8. Microscope observation demonstrated the fluorescently labeled AcAtg8 was localized in the cytoplasm and autophagosome of A. chrysogenum, and the expression of Acatg8 was induced by nutrient starvation. Gene disruption and genetic complementation revealed that Acatg8 is essential for autophagosome formation. Disruption of Acatg8 significantly reduced fungal conidiation and delayed conidial germination. Localization of GFP-AcAtg8 implied that autophagy is involved in the early phase of conidial germination. Similar to Acatg1, disruption of Acatg8 remarkably enhanced cephalosporin C yield. The cephalosporin C biosynthetic enzymes (isopenicillin N synthase PcbC and isopenicillin N epimerase CefD2) and peroxisomes were accumulated in the Acatg8 disruption mutant (∆Acatg8), which might be the main reasons for the enhancement of cephalosporin C production. However, the biomass of ΔAcatg8 decreased drastically at the late stage of fermentation, suggesting that autophagy is critical for A. chrysogenum cell survival under nutrition deprived condition. Disruption of Acatg8 also resulted in accumulation of mitochondria, which might produce more reactive oxygen species (ROS) which promotes fungal death. However, the premature death is unfavorable for cephalosporin C production. To solve this problem, a plasmid containing Acatg8 under control of the xylose/xylan-inducible promoter was introduced into ∆Acatg8. Conidiation and growth of the recombinant strain restored to the wild-type level in the medium supplemented with xylose, while the cephalosporin C production maintained at a high level even prolonged fermentation. Conclusions Our results demonstrated inducible expression of Acatg8 and disruption of Acatg8 remarkably increased cephalosporin C production. This study provides a promising approach for yield improvement of cephalosporin C in A. chrysogenum. Electronic supplementary material The online version of this article (10.1186/s12934-018-1021-9) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Honghua Li
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Pengjie Hu
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Ying Wang
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Yuanyuan Pan
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Gang Liu
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China. .,University of Chinese Academy of Sciences, Beijing, 100049, China.
| |
Collapse
|
23
|
Zientara-Rytter K, Sirko A. To deliver or to degrade - an interplay of the ubiquitin-proteasome system, autophagy and vesicular transport in plants. FEBS J 2017; 283:3534-3555. [PMID: 26991113 DOI: 10.1111/febs.13712] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Revised: 02/21/2016] [Accepted: 03/14/2016] [Indexed: 12/21/2022]
Abstract
The efficient utilization and subsequent reuse of cell components is a key factor in determining the proper growth and functioning of all cells under both optimum and stress conditions. The process of intracellular and intercellular recycling is especially important for the appropriate control of cellular metabolism and nutrient management in immobile organisms, such as plants. Therefore, the accurate recycling of amino acids, lipids, carbohydrates or micro- and macronutrients available in the plant cell becomes a critical factor that ensures plant survival and growth. Plant cells possess two main degradation mechanisms: a ubiquitin-proteasome system and autophagy, which, as a part of an intracellular trafficking system, is based on vesicle transport. This review summarizes knowledge of both the ubiquitin-proteasome system and autophagy pathways, describes the cross-talk between the two and discusses the relationships between autophagy and the vesicular transport systems.
Collapse
Affiliation(s)
| | - Agnieszka Sirko
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| |
Collapse
|
24
|
Havé M, Marmagne A, Chardon F, Masclaux-Daubresse C. Nitrogen remobilization during leaf senescence: lessons from Arabidopsis to crops. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:2513-2529. [PMID: 27707774 DOI: 10.1093/jxb/erw365] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
As a result of climate changes, land use and agriculture have to adapt to new demands. Agriculture is responsible for a large part of the greenhouse gas (GHG) emissions that have to be urgently reduced in order to protect the environment. At the same time, agriculture has to cope with the challenges of sustainably feeding a growing world population. Reducing the use of the ammonia-nitrate fertilizers that are responsible for a large part of the GHGs released and that have a negative impact on carbon balance is one of the objectives of precision agriculture. One way to reduce N fertilizers without dramatically affecting grain yields is to improve the nitrogen recycling and remobilization performances of plants. Mechanisms involved in nitrogen recycling, such as autophagy, are essential for nutrient remobilization at the whole-plant level and for seed quality. Studies on leaf senescence and nutrient recycling provide new perspectives for improvement. The aim of this review is to give an overview of the mechanisms involved in nitrogen recycling and remobilization during leaf senescence and to present the different approaches undertaken to improve nitrogen remobilization efficiency using both model plants and crop species.
Collapse
Affiliation(s)
- Marien Havé
- INRA-AgroParisTech, Institut Jean-Pierre Bourgin, UMR1318, ERL CNRS 3559, Saclay Plant Sciences, Versailles, France
| | - Anne Marmagne
- INRA-AgroParisTech, Institut Jean-Pierre Bourgin, UMR1318, ERL CNRS 3559, Saclay Plant Sciences, Versailles, France
| | - Fabien Chardon
- INRA-AgroParisTech, Institut Jean-Pierre Bourgin, UMR1318, ERL CNRS 3559, Saclay Plant Sciences, Versailles, France
| | - Céline Masclaux-Daubresse
- INRA-AgroParisTech, Institut Jean-Pierre Bourgin, UMR1318, ERL CNRS 3559, Saclay Plant Sciences, Versailles, France
| |
Collapse
|
25
|
Degradation of organelles or specific organelle components via selective autophagy in plant cells. Int J Mol Sci 2014; 15:7624-38. [PMID: 24802874 PMCID: PMC4057695 DOI: 10.3390/ijms15057624] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2014] [Revised: 03/31/2014] [Accepted: 04/16/2014] [Indexed: 12/13/2022] Open
Abstract
Macroautophagy (hereafter referred to as autophagy) is a cellular mechanism dedicated to the degradation and recycling of unnecessary cytosolic components by their removal to the lytic compartment of the cell (the vacuole in plants). Autophagy is generally induced by stresses causing energy deprivation and its operation occurs by special vesicles, termed autophagosomes. Autophagy also operates in a selective manner, recycling specific components, such as organelles, protein aggregates or even specific proteins, and selective autophagy is implicated in both cellular housekeeping and response to stresses. In plants, selective autophagy has recently been shown to degrade mitochondria, plastids and peroxisomes, or organelle components such as the endoplasmic-reticulum (ER) membrane and chloroplast-derived proteins such as Rubisco. This ability places selective-autophagy as a major factor in cellular steady-state maintenance, both under stress and favorable environmental conditions. Here we review the recent advances documented in plants for this cellular process and further discuss its impact on plant physiology.
Collapse
|