101
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Li H, Li Y, Zhao Q, Li T, Wei J, Li B, Shen W, Yang C, Zeng Y, Rodriguez PL, Zhao Y, Jiang L, Wang X, Gao C. The plant ESCRT component FREE1 shuttles to the nucleus to attenuate abscisic acid signalling. NATURE PLANTS 2019; 5:512-524. [PMID: 30962512 DOI: 10.1038/s41477-019-0400-5] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 03/05/2019] [Indexed: 05/21/2023]
Abstract
The endosomal sorting complex required for transport (ESCRT) machinery has been well documented for its function in endosomal sorting in eukaryotes. Here, we demonstrate an up-to-now unknown and non-endosomal function of the ESCRT component in plants. We show that FYVE DOMAIN PROTEIN REQUIRED FOR ENDOSOMAL SORTING 1 (FREE1), a recently identified plant-specific ESCRT component essential for multivesicular body biogenesis, plays additional functions in the nucleus in transcriptional inhibition of abscisic acid (ABA) signalling. Following ABA treatment, SNF1-related protein kinase 2 (SnRK2) kinases phosphorylate FREE1, a step requisite for ABA-induced FREE1 nuclear import. In the nucleus, FREE1 interacts with the basic leucine zipper transcription factors ABA-RESPONSIVE ELEMENTS BINDING FACTOR4 and ABA-INSENSITIVE5 to reduce their binding to the cis-regulatory sequences of downstream genes. Collectively, our study demonstrates the crosstalk between endomembrane trafficking and ABA signalling at the transcriptional level and highlights the moonlighting properties of the plant ESCRT subunit FREE1, which has evolved unique non-endosomal functions in the nucleus besides its roles in membrane trafficking in the cytoplasm.
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Affiliation(s)
- Hongbo Li
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University (SCNU), Guangzhou, China
| | - Yingzhu Li
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University (SCNU), Guangzhou, China
| | - Qiong Zhao
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Tingting Li
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University (SCNU), Guangzhou, China
| | - Juan Wei
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University (SCNU), Guangzhou, 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, Hong Kong, China
| | - Wenjin Shen
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University (SCNU), Guangzhou, China
| | - Chao Yang
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University (SCNU), Guangzhou, China
| | - Yonglun Zeng
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Pedro L Rodriguez
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas-Universidad Politécnica de Valencia, Valencia, Spain
| | - Yunde Zhao
- Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA, USA
| | - Liwen Jiang
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong, China.
| | - Xiaojing Wang
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University (SCNU), Guangzhou, China.
| | - Caiji Gao
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University (SCNU), Guangzhou, China.
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102
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Li H, Li Y, Zhao Q, Li T, Wei J, Li B, Shen W, Yang C, Zeng Y, Rodriguez PL, Zhao Y, Jiang L, Wang X, Gao C. The plant ESCRT component FREE1 shuttles to the nucleus to attenuate abscisic acid signalling. NATURE PLANTS 2019; 5:512-524. [PMID: 30962512 DOI: 10.1038/s41477-019-0400-405] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 03/05/2019] [Indexed: 05/28/2023]
Abstract
The endosomal sorting complex required for transport (ESCRT) machinery has been well documented for its function in endosomal sorting in eukaryotes. Here, we demonstrate an up-to-now unknown and non-endosomal function of the ESCRT component in plants. We show that FYVE DOMAIN PROTEIN REQUIRED FOR ENDOSOMAL SORTING 1 (FREE1), a recently identified plant-specific ESCRT component essential for multivesicular body biogenesis, plays additional functions in the nucleus in transcriptional inhibition of abscisic acid (ABA) signalling. Following ABA treatment, SNF1-related protein kinase 2 (SnRK2) kinases phosphorylate FREE1, a step requisite for ABA-induced FREE1 nuclear import. In the nucleus, FREE1 interacts with the basic leucine zipper transcription factors ABA-RESPONSIVE ELEMENTS BINDING FACTOR4 and ABA-INSENSITIVE5 to reduce their binding to the cis-regulatory sequences of downstream genes. Collectively, our study demonstrates the crosstalk between endomembrane trafficking and ABA signalling at the transcriptional level and highlights the moonlighting properties of the plant ESCRT subunit FREE1, which has evolved unique non-endosomal functions in the nucleus besides its roles in membrane trafficking in the cytoplasm.
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Affiliation(s)
- Hongbo Li
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University (SCNU), Guangzhou, China
| | - Yingzhu Li
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University (SCNU), Guangzhou, China
| | - Qiong Zhao
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Tingting Li
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University (SCNU), Guangzhou, China
| | - Juan Wei
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University (SCNU), Guangzhou, 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, Hong Kong, China
| | - Wenjin Shen
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University (SCNU), Guangzhou, China
| | - Chao Yang
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University (SCNU), Guangzhou, China
| | - Yonglun Zeng
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Pedro L Rodriguez
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas-Universidad Politécnica de Valencia, Valencia, Spain
| | - Yunde Zhao
- Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA, USA
| | - Liwen Jiang
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong, China.
| | - Xiaojing Wang
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University (SCNU), Guangzhou, China.
| | - Caiji Gao
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University (SCNU), Guangzhou, China.
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103
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Chung T. How phosphoinositides shape autophagy in plant cells. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2019; 281:146-158. [PMID: 30824047 DOI: 10.1016/j.plantsci.2019.01.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 01/10/2019] [Accepted: 01/19/2019] [Indexed: 05/06/2023]
Abstract
Plant cells use autophagy to degrade their own cytoplasm in vacuoles, thereby not only recycling their breakdown products, but also ensuring the homeostasis of essential cytoplasmic constituents and organelles. Plants and other eukaryotes have a conserved set of core Autophagy-related (ATG) genes involved in the biogenesis of the autophagosome, the main autophagic compartment destined for the lytic vacuole. In the past decade, the core ATG genes were isolated from several plant species. The core ATG proteins include the components of the VACUOLAR PROTEIN SORTING 34 (VPS34) complex that is responsible for the local production of phosphatidylinositol 3-phosphate (PI3P) at the site of autophagosome formation. Dissecting the roles of PI3P and its effectors in autophagy is challenging, because of the multi-faceted links between autophagosomal and endosomal systems. This review highlights recent studies on putative plant PI3P effectors involved in autophagosome dynamics. Molecular mechanisms underlying the requirement of PI3P for autophagosome biogenesis and trafficking are also discussed.
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Affiliation(s)
- Taijoon Chung
- Department of Biological Sciences, Pusan National University, Busan, 46241, Republic of Korea.
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104
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Xie Q, Chen A, Zhang Y, Yuan M, Xie W, Zhang C, Zheng W, Wang Z, Li G, Zhou J. Component Interaction of ESCRT Complexes Is Essential for Endocytosis-Dependent Growth, Reproduction, DON Production and Full Virulence in Fusarium graminearum. Front Microbiol 2019; 10:180. [PMID: 30809208 PMCID: PMC6379464 DOI: 10.3389/fmicb.2019.00180] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2018] [Accepted: 01/23/2019] [Indexed: 01/18/2023] Open
Abstract
Multivesicular bodies (MVBs) are critical intermediates in the trafficking of ubiquitinated endocytosed surface proteins to the lysosome/vacuole for destruction. Recognizing and packaging ubiquitin modified cargoes to the MVB pathway require ESCRT (Endosomal sorting complexes required for transport) machinery, which consists of four core subcomplexes, ESCRT-0, ESCRT-I, ESCRT-II, and ESCRT-III. Fusarium graminearum is an important plant pathogen that causes head blight of major cereal crops. Our previous results showed that ESCRT-0 is essential for fungal development and pathogenicity in Fusarium graminearum. We then, in this study, systemically studied the protein-protein interactions within F. graminearum ESCRT-I, -II or -III complex, as well as between ESCRT-0 and ESCRT-I, ESCRT-I and ESCRT-II, and ESCRT-II and ESCRT-III complexes and found that loss of any ESCRT component resulted in abnormal function in endocytosis. In addition, ESCRT deletion mutants displayed severe defects in growth, deoxynivalenol (DON) production, virulence, sexual, and asexual reproduction. Importantly genetic complementation with corresponding ESCRT genes fully rescued all these defective phenotypes, indicating the essential role of ESCRT machinery in fungal development and plant infection in F. graminearum. Taken together, the protein-protein interactome and biological functions of the ESCRT machinery is first profoundly characterized in F. graminearum, providing a foundation for further exploration of ESCRT machinery in filamentous fungi.
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Affiliation(s)
- Qiurong Xie
- Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
- Fujian University Key Laboratory for Plant-Microbe Interaction, School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Ahai Chen
- Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
- Fujian University Key Laboratory for Plant-Microbe Interaction, School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Yunzhi Zhang
- Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
- Fujian University Key Laboratory for Plant-Microbe Interaction, School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Mingyue Yuan
- Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
- Fujian University Key Laboratory for Plant-Microbe Interaction, School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Wei Xie
- Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
- Fujian University Key Laboratory for Plant-Microbe Interaction, School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Chengkang Zhang
- Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
- Fujian University Key Laboratory for Plant-Microbe Interaction, School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Wenhui Zheng
- Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
- Fujian University Key Laboratory for Plant-Microbe Interaction, School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Zonghua Wang
- Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
- Institute of Oceanography, Minjiang University, Fuzhou, China
| | - Guangpu Li
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
- Peggy and Charles Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - Jie Zhou
- Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
- Fujian University Key Laboratory for Plant-Microbe Interaction, School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
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105
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Dubeaux G, Neveu J, Zelazny E, Vert G. Metal Sensing by the IRT1 Transporter-Receptor Orchestrates Its Own Degradation and Plant Metal Nutrition. Mol Cell 2019; 69:953-964.e5. [PMID: 29547723 DOI: 10.1016/j.molcel.2018.02.009] [Citation(s) in RCA: 186] [Impact Index Per Article: 37.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 12/22/2017] [Accepted: 02/05/2018] [Indexed: 12/21/2022]
Abstract
Plant roots forage the soil for iron, the concentration of which can be dramatically lower than those needed for growth. Soil iron uptake uses the broad metal spectrum IRT1 transporter that also transports zinc, manganese, cobalt, and cadmium. Sophisticated iron-dependent transcriptional regulatory mechanisms allow plants to tightly control the abundance of IRT1, ensuring optimal absorption of iron. Here, we uncover that IRT1 acts as a transporter and receptor (transceptor), directly sensing excess of its non-iron metal substrates in the cytoplasm, to regulate its own degradation. Direct metal binding to a histidine-rich stretch in IRT1 triggers its phosphorylation by the CIPK23 kinase and facilitates the subsequent recruitment of the IDF1 E3 ligase. CIPK23-driven phosphorylation and IDF1-mediated lysine-63 polyubiquitination are jointly required for efficient endosomal sorting and vacuolar degradation of IRT1. Thus, IRT1 directly senses elevated non-iron metal concentrations and integrates multiple substrate-dependent regulations to optimize iron uptake and protect plants from highly reactive metals.
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Affiliation(s)
- Guillaume Dubeaux
- Institute for Integrative Biology of the Cell (I2BC), CNRS/CEA/Univ. Paris Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette, France
| | - Julie Neveu
- Institute for Integrative Biology of the Cell (I2BC), CNRS/CEA/Univ. Paris Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette, France
| | - Enric Zelazny
- Institute for Integrative Biology of the Cell (I2BC), CNRS/CEA/Univ. Paris Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette, France
| | - Grégory Vert
- Institute for Integrative Biology of the Cell (I2BC), CNRS/CEA/Univ. Paris Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette, France.
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106
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Nagel MK, Vogel K, Isono E. Transient Expression of ESCRT Components in Arabidopsis Root Cell Suspension Culture-Derived Protoplasts. Methods Mol Biol 2019; 1998:163-174. [PMID: 31250301 DOI: 10.1007/978-1-4939-9492-2_12] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Localization studies are important to understand the function of diverse proteins. The endosomal trafficking pathway is very complex, and a lot of proteins function in this pathway, primarily the endosomal sorting complexes required for transport (ESCRTs). Some of the ESCRT-related proteins or mutant variants cannot be stably expressed in planta due to the toxicity of their expression. Therefore, a transient expression system is necessary to study their function. Transient expression in protoplasts from Arabidopsis root cell-derived culture serves as a fast and reliable method for the expression and cell biological and biochemical analyses of otherwise toxic constructs.
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Affiliation(s)
- Marie-Kristin Nagel
- Plant Physiology and Biochemistry, Department of Biology, University of Konstanz, Konstanz, Germany
| | - Karin Vogel
- Plant Physiology and Biochemistry, Department of Biology, University of Konstanz, Konstanz, Germany
| | - Erika Isono
- Plant Physiology and Biochemistry, Department of Biology, University of Konstanz, Konstanz, Germany.
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107
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Cui Y, Cao W, He Y, Zhao Q, Wakazaki M, Zhuang X, Gao J, Zeng Y, Gao C, Ding Y, Wong HY, Wong WS, Lam HK, Wang P, Ueda T, Rojas-Pierce M, Toyooka K, Kang BH, Jiang L. A whole-cell electron tomography model of vacuole biogenesis in Arabidopsis root cells. NATURE PLANTS 2019; 5:95-105. [PMID: 30559414 DOI: 10.1038/s41477-018-0328-1] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Accepted: 11/14/2018] [Indexed: 05/20/2023]
Abstract
Plant vacuoles are dynamic organelles that play essential roles in regulating growth and development. Two distinct models of vacuole biogenesis have been proposed: separate vacuoles are formed by the fusion of endosomes, or the single interconnected vacuole is derived from the endoplasmic reticulum. These two models are based on studies of two-dimensional (2D) transmission electron microscopy and 3D confocal imaging, respectively. Here, we performed 3D electron tomography at nanometre resolution to illustrate vacuole biogenesis in Arabidopsis root cells. The whole-cell electron tomography analysis first identified unique small vacuoles (SVs; 400-1,000 nm in diameter) as nascent vacuoles in early developmental cortical cells. These SVs contained intraluminal vesicles and were mainly derived/matured from multivesicular body (MVB) fusion. The whole-cell vacuole models and statistical analysis on wild-type root cells of different vacuole developmental stages demonstrated that central vacuoles were derived from MVB-to-SV transition and subsequent fusions of SVs. Further electron tomography analysis on mutants defective in MVB formation/maturation or vacuole fusion demonstrated that central vacuole formation required functional MVBs and membrane fusion machineries.
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Affiliation(s)
- Yong Cui
- 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.
| | - Wenhan Cao
- 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
| | - Yilin He
- 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
| | - Qiong Zhao
- 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
| | - Mayumi Wakazaki
- RIKEN Center for Sustainable Resource Science, Yokohama, Japan
| | - 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
| | - Jiayang Gao
- 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
| | - 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
| | - Caiji Gao
- 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
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Yu Ding
- 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
- Department of Food Science & Technology, School of Science and Technology, Jinan University, Guangzhou, China
| | - Hiu Yan Wong
- 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
| | - Wing Shing Wong
- 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
| | - Ham Karen Lam
- 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
| | - Pengfei Wang
- 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
| | - Takashi Ueda
- Division of Cellular Dynamics, National Institute for Basic Biology, Okazaki, Japan
| | - Marcela Rojas-Pierce
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC, USA
| | | | - Byung-Ho Kang
- 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
| | - 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 Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, China.
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108
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Huang S, Jiang L, Zhuang X. Possible Roles of Membrane Trafficking Components for Lipid Droplet Dynamics in Higher Plants and Green Algae. FRONTIERS IN PLANT SCIENCE 2019; 10:207. [PMID: 30858860 PMCID: PMC6397863 DOI: 10.3389/fpls.2019.00207] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 02/07/2019] [Indexed: 05/04/2023]
Abstract
Lipid droplets are ubiquitous dynamic organelles that contain neutral lipids surrounded by a phospholipid monolayer. They can store and supply lipids for energy metabolism and membrane synthesis. In addition, protein transport and lipid exchange often occur between LDs and various organelles to control lipid homeostasis in response to multiple stress responses and cellular signaling. In recent years, multiple membrane trafficking proteins have been identified through LD proteomics and genetic analyses. These membrane trafficking machineries are emerging as critical regulators to function in different LD-organelle interactions, e.g., for LD dynamics, biogenesis and turnover. In this review, we will summarize recent advances in regard to LD-related membrane trafficking proteins and discuss future investigations in higher plants and green algae.
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Affiliation(s)
- Shuxian Huang
- Centre for Cell and Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Liwen Jiang
- Centre for Cell and Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
- The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, China
| | - Xiaohong Zhuang
- Centre for Cell and Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
- *Correspondence: Xiaohong Zhuang,
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109
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Cui Y, Cao W, He Y, Zhao Q, Wakazaki M, Zhuang X, Gao J, Zeng Y, Gao C, Ding Y, Wong HY, Wong WS, Lam HK, Wang P, Ueda T, Rojas-Pierce M, Toyooka K, Kang BH, Jiang L. A whole-cell electron tomography model of vacuole biogenesis in Arabidopsis root cells. NATURE PLANTS 2019; 5:95-105. [PMID: 30559414 DOI: 10.1038/s41477-018-0328-321] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Accepted: 11/14/2018] [Indexed: 05/28/2023]
Abstract
Plant vacuoles are dynamic organelles that play essential roles in regulating growth and development. Two distinct models of vacuole biogenesis have been proposed: separate vacuoles are formed by the fusion of endosomes, or the single interconnected vacuole is derived from the endoplasmic reticulum. These two models are based on studies of two-dimensional (2D) transmission electron microscopy and 3D confocal imaging, respectively. Here, we performed 3D electron tomography at nanometre resolution to illustrate vacuole biogenesis in Arabidopsis root cells. The whole-cell electron tomography analysis first identified unique small vacuoles (SVs; 400-1,000 nm in diameter) as nascent vacuoles in early developmental cortical cells. These SVs contained intraluminal vesicles and were mainly derived/matured from multivesicular body (MVB) fusion. The whole-cell vacuole models and statistical analysis on wild-type root cells of different vacuole developmental stages demonstrated that central vacuoles were derived from MVB-to-SV transition and subsequent fusions of SVs. Further electron tomography analysis on mutants defective in MVB formation/maturation or vacuole fusion demonstrated that central vacuole formation required functional MVBs and membrane fusion machineries.
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Affiliation(s)
- Yong Cui
- 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.
| | - Wenhan Cao
- 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
| | - Yilin He
- 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
| | - Qiong Zhao
- 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
| | - Mayumi Wakazaki
- RIKEN Center for Sustainable Resource Science, Yokohama, Japan
| | - 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
| | - Jiayang Gao
- 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
| | - 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
| | - Caiji Gao
- 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
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Yu Ding
- 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
- Department of Food Science & Technology, School of Science and Technology, Jinan University, Guangzhou, China
| | - Hiu Yan Wong
- 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
| | - Wing Shing Wong
- 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
| | - Ham Karen Lam
- 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
| | - Pengfei Wang
- 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
| | - Takashi Ueda
- Division of Cellular Dynamics, National Institute for Basic Biology, Okazaki, Japan
| | - Marcela Rojas-Pierce
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC, USA
| | | | - Byung-Ho Kang
- 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
| | - 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 Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, China.
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110
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Physiological Functions of Phosphoinositide-Modifying Enzymes and Their Interacting Proteins in Arabidopsis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018. [PMID: 30499079 DOI: 10.1007/5584_2018_295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register]
Abstract
The integrity of cellular membranes is maintained not only by structural phospholipids such as phosphatidylcholine and phosphatidylethanolamine, but also by regulatory phospholipids, phosphatidylinositol phosphates (phosphoinositides). Although phosphoinositides constitute minor membrane phospholipids, they exert a wide variety of regulatory functions in all eukaryotic cells. They act as key markers of membrane surfaces that determine the biological integrity of cellular compartments to recruit various phosphoinositide-binding proteins. This review focuses on recent progress on the significance of phosphoinositides, their modifying enzymes, and phosphoinositide-binding proteins in Arabidopsis.
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111
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Pocsfalvi G, Turiák L, Ambrosone A, Del Gaudio P, Puska G, Fiume I, Silvestre T, Vékey K. Protein biocargo of citrus fruit-derived vesicles reveals heterogeneous transport and extracellular vesicle populations. JOURNAL OF PLANT PHYSIOLOGY 2018; 229:111-121. [PMID: 30056374 DOI: 10.1016/j.jplph.2018.07.006] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 07/18/2018] [Accepted: 07/20/2018] [Indexed: 06/08/2023]
Abstract
Cell-derived vesicles are membrane-enclosed organelles that transport material inside and outside the cell. Plant-derived vesicles are receiving more and more attention due to their potential as nanovectors for the delivery of biologically active substances. Here, we studied the heterogeneity and protein biocargo in citrus fruit juice sac cell-derived vesicles populations. Micro- and nano-sized vesicle fractions were isolated from four citrus species, C. sinensis, C. limon, C. paradisi and C. aurantium, characterized using physicochemical methods and protein cargos were compared using label-free quantitative shotgun proteomics. In each sample approximately 600-800 proteins were identified. Orthologues of most of the top-ranking proteins have previously been reported in extracellular vesicles of mammalian origin. High expression levels of patellin-3-like, clathrin heavy chain, heat shock proteins, 14-3-3 protein, glyceraldehyde-3-phosphate dehydrogenase and fructose-bisphosphate aldolase 6 were measured in all samples while aquaporin was highly expressed only in the nanovesicle fractions. Bioinformatics revealed more than hundred protein orthologues potentially implicated in vesicular trafficking. In particular, the presence of CCV, COPI and COPII coat proteins indicates the presence of heterogeneous populations of intracellular transport vesicles. Moreover, a high number of different enzymes including hydrolases and oxidoreductases are ubiquities in citrus fruit sac cell-derived vesicles.
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Affiliation(s)
- Gabriella Pocsfalvi
- Institute of Biosciences and BioResources, National Research Council of Italy, Italy.
| | - Lilla Turiák
- MS Proteomics Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Hungary
| | | | | | - Gina Puska
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, Hungary
| | - Immacolata Fiume
- Institute of Biosciences and BioResources, National Research Council of Italy, Italy
| | - Teresa Silvestre
- Institute of Biosciences and BioResources, National Research Council of Italy, Italy
| | - Károly Vékey
- MS Proteomics Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Hungary
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112
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Shen J, Zhao Q, Wang X, Gao C, Zhu Y, Zeng Y, Jiang L. A plant Bro1 domain protein BRAF regulates multivesicular body biogenesis and membrane protein homeostasis. Nat Commun 2018; 9:3784. [PMID: 30224707 PMCID: PMC6141507 DOI: 10.1038/s41467-018-05913-y] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 08/06/2018] [Indexed: 02/07/2023] Open
Abstract
Plant development, defense, and many physiological processes rely on the endosomal sorting complex required for transport (ESCRT) machinery to control the homeostasis of membrane proteins by selective vacuolar degradation. Although ESCRT core components are conserved among higher eukaryotes, the regulators that control the function of the ESCRT machinery remain elusive. We recently identified a plant-specific ESCRT component, FREE1, that is essential for multivesicular body/prevacuolar compartment (MVB/PVC) biogenesis and vacuolar sorting of membrane proteins. Here we identify a plant-specific Bro1-domain protein BRAF, which regulates FREE1 recruitment to the MVB/PVC membrane by competitively binding to the ESCRT-I component Vps23. Altogether, we have successfully identified a role for BRAF, whose function as a unique evolutionary ESCRT regulator in orchestrating intraluminal vesicle formation in MVB/PVCs and the sorting of membrane proteins for degradation in plants makes it an important regulatory mechanism underlying the ESCRT machinery in higher eukaryotes.
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Affiliation(s)
- Jinbo Shen
- Centre for Cell & Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Linan, Hangzhou, 311300, China.
| | - Qiong Zhao
- Centre for Cell & Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Xiangfeng Wang
- Centre for Cell & Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
- State Key Laboratory of Plant Physiology and Biochemistry, Department of Plant Sciences, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Caiji Gao
- Centre for Cell & Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University (SCNU), Guangzhou, 510631, China
| | - Ying Zhu
- Centre for Cell & Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Yonglun Zeng
- Centre for Cell & Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Liwen Jiang
- Centre for Cell & Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
- CUHK Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, 518057, China.
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113
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Zhou JJ, Luo J. The PIN-FORMED Auxin Efflux Carriers in Plants. Int J Mol Sci 2018; 19:E2759. [PMID: 30223430 PMCID: PMC6164769 DOI: 10.3390/ijms19092759] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 09/11/2018] [Accepted: 09/12/2018] [Indexed: 12/14/2022] Open
Abstract
Auxin plays crucial roles in multiple developmental processes, such as embryogenesis, organogenesis, cell determination and division, as well as tropic responses. These processes are finely coordinated by the auxin, which requires the polar distribution of auxin within tissues and cells. The intercellular directionality of auxin flow is closely related to the asymmetric subcellular location of PIN-FORMED (PIN) auxin efflux transporters. All PIN proteins have a conserved structure with a central hydrophilic loop domain, which harbors several phosphosites targeted by a set of protein kinases. The activities of PIN proteins are finely regulated by diverse endogenous and exogenous stimuli at multiple layers-including transcriptional and epigenetic levels, post-transcriptional modifications, subcellular trafficking, as well as PINs' recycling and turnover-to facilitate the developmental processes in an auxin gradient-dependent manner. Here, the recent advances in the structure, evolution, regulation and functions of PIN proteins in plants will be discussed. The information provided by this review will shed new light on the asymmetric auxin-distribution-dependent development processes mediated by PIN transporters in plants.
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Affiliation(s)
- Jing-Jing Zhou
- College of Horticulture and Forestry Science, Hubei Engineering Technology Research Center for Forestry Information, Huazhong Agricultural University, Wuhan 430070, China.
| | - Jie Luo
- College of Horticulture and Forestry Science, Hubei Engineering Technology Research Center for Forestry Information, Huazhong Agricultural University, Wuhan 430070, China.
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114
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Yuan R, Lan J, Fang Y, Yu H, Zhang J, Huang J, Qin G. The Arabidopsis USL1 controls multiple aspects of development by affecting late endosome morphology. THE NEW PHYTOLOGIST 2018; 219:1388-1405. [PMID: 29897620 PMCID: PMC6099276 DOI: 10.1111/nph.15249] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2017] [Accepted: 04/21/2018] [Indexed: 05/07/2023]
Abstract
The polar transport of auxin controls many aspects of plant development. However, the molecular mechanisms underlying auxin tranport regulation remain to be further elucidated. We identified a mutant named as usl1 (unflattened and small leaves) in a genetic screen in Arabidopsis thaliana. The usl1 displayed multiple aspects of developmental defects in leaves, embryogenesis, cotyledons, silique phyllotaxy and lateral roots in addition to abnormal leaves. USL1 encodes a protein orthologous to the yeast vacuolar protein sorting (Vps) 38p and human UV RADIATION RESISTANCE-ASSOCIATED GENE (UVRAG). Cell biology, Co-IP/MS and yeast two-hybrid were used to identify the function of USL1. USL1 colocalizes at the subcellular level with VPS29, a key factor of the retromer complex that controls auxin transport. The morphology of the VPS29-associated late endosomes (LE) is altered from small dots in the wild-type to aberrant enlarged circles in the usl1 mutants. The usl1 mutant synergistically interacts with vps29. We also found that USL1 forms a complex with AtVPS30 and AtVPS34. We propose that USL1 controls multiple aspects of plant development by affecting late endosome morphology and by regulating the PIN1 polarity. Our findings provide a new layer of the understanding on the mechanisms of plant development regulation.
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Affiliation(s)
- Rongrong Yuan
- State Key Laboratory of Protein and Plant Gene ResearchSchool of Life SciencesSchool of Advanced Agricultural SciencesPeking UniversityBeijing100871China
- The Peking‐Tsinghua Center for Life SciencesAcademy for Advanced Interdisciplinary StudiesPeking UniversityBeijing100871China
| | - Jingqiu Lan
- State Key Laboratory of Protein and Plant Gene ResearchSchool of Life SciencesSchool of Advanced Agricultural SciencesPeking UniversityBeijing100871China
| | - Yuxing Fang
- State Key Laboratory of Protein and Plant Gene ResearchSchool of Life SciencesSchool of Advanced Agricultural SciencesPeking UniversityBeijing100871China
| | - Hao Yu
- State Key Laboratory of Protein and Plant Gene ResearchSchool of Life SciencesSchool of Advanced Agricultural SciencesPeking UniversityBeijing100871China
| | - Jinzhe Zhang
- State Key Laboratory of Protein and Plant Gene ResearchSchool of Life SciencesSchool of Advanced Agricultural SciencesPeking UniversityBeijing100871China
| | - Jiaying Huang
- State Key Laboratory of Protein and Plant Gene ResearchSchool of Life SciencesSchool of Advanced Agricultural SciencesPeking UniversityBeijing100871China
| | - Genji Qin
- State Key Laboratory of Protein and Plant Gene ResearchSchool of Life SciencesSchool of Advanced Agricultural SciencesPeking UniversityBeijing100871China
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115
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Ashnest JR, Gendall AR. Trafficking to the seed protein storage vacuole. FUNCTIONAL PLANT BIOLOGY : FPB 2018; 45:895-910. [PMID: 32291054 DOI: 10.1071/fp17318] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Accepted: 02/17/2018] [Indexed: 06/11/2023]
Abstract
The processing and subcellular trafficking of seed storage proteins is a critical area of physiological, agricultural and biotechnological research. Trafficking to the lytic vacuole has been extensively discussed in recent years, without substantial distinction from trafficking to the protein storage vacuole (PSV). However, despite some overlap between these pathways, there are several examples of unique processing and machinery in the PSV pathway. Moreover, substantial new data has recently come to light regarding the important players in this pathway, in particular, the intracellular NHX proteins and their role in regulating lumenal pH. In some cases, these new data are limited to genetic evidence, with little mechanistic understanding. As such, the implications of these data in the current paradigm of PSV trafficking is perhaps yet unclear. Although it has generally been assumed that the major classes of storage proteins are trafficked via the same pathway, there is mounting evidence that the 12S globulins and 2S albumins may be trafficked independently. Advances in identification of vacuolar targeting signals, as well as an improved mechanistic understanding of various vacuolar sorting receptors, may reveal the differences in these trafficking pathways.
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Affiliation(s)
- Joanne R Ashnest
- Department of Animal, Plant and Soil Sciences, AgriBio, Centre for AgriBiosciences, 5 Ring Road, La Trobe University, Bundoora, Vic. 3086, Australia
| | - Anthony R Gendall
- Department of Animal, Plant and Soil Sciences, AgriBio, Centre for AgriBiosciences, 5 Ring Road, La Trobe University, Bundoora, Vic. 3086, Australia
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116
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Liu C, Shen W, Yang C, Zeng L, Gao C. Knowns and unknowns of plasma membrane protein degradation in plants. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2018; 272:55-61. [PMID: 29807606 DOI: 10.1016/j.plantsci.2018.04.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 04/02/2018] [Accepted: 04/10/2018] [Indexed: 06/08/2023]
Abstract
Plasma membrane (PM) not only creates a physical barrier to enclose the intracellular compartments but also mediates the direct communication between plants and the ever-changing environment. A tight control of PM protein homeostasis by selective degradation is thus crucial for proper plant development and plant-environment interactions. Accumulated evidences have shown that a number of plant PM proteins undergo clathrin-dependent or membrane microdomain-associated endocytic routes to vacuole for degradation in a cargo-ubiquitination dependent or independent manner. Besides, several trans-acting determinants involved in the regulation of endocytosis, recycling and multivesicular body-mediated vacuolar sorting have been identified in plants. More interestingly, recent findings have uncovered the participation of selective autophagy in PM protein turnover in plants. Although great progresses have been made to identify the PM proteins that undergo dynamic changes in subcellular localizations and to explore the factors that control the membrane protein trafficking, several questions remain to be answered regarding the molecular mechanisms of PM protein degradation in plants. In this short review article, we briefly summarize recent progress in our understanding of the internalization, sorting and degradation of plant PM proteins. More specifically, we focus on discussing the elusive aspects underlying the pathways of PM protein degradation in plants.
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Affiliation(s)
- Chuanliang Liu
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Wenjin Shen
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Chao Yang
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Lizhang Zeng
- Institute for Brain Research and Rehabilitation, South China Normal University, Guangzhou 510631, China
| | - Caiji Gao
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou 510631, China.
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117
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ESCRT-mediated sorting and intralumenal vesicle concatenation in plants. Biochem Soc Trans 2018; 46:537-545. [PMID: 29666213 DOI: 10.1042/bst20170439] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2018] [Revised: 03/09/2018] [Accepted: 03/16/2018] [Indexed: 12/16/2022]
Abstract
The degradation of plasma membrane and other membrane-associated proteins require their sorting at endosomes for delivery to the vacuole. Through the endocytic pathway, ubiquitinated membrane proteins (cargo) are delivered to endosomes where the ESCRT (endosomal sorting complex required for transport) machinery sorts them into intralumenal vesicles for degradation. Plants contain both conserved and plant-specific ESCRT subunits. In this review, I discuss the role of characterized plant ESCRT components, the evolutionary diversification of the plant ESCRT machinery, and a recent study showing that endosomal intralumenal vesicles form in clusters of concatenated vesicle buds by temporally uncoupling membrane constriction from membrane fission.
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118
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Qian J, Chen Y, Hu Y, Deng Y, Liu Y, Li G, Zou W, Zhao J. Arabidopsis replication factor C4 is critical for DNA replication during the mitotic cell cycle. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2018; 94:288-303. [PMID: 29406597 DOI: 10.1111/tpj.13855] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 01/16/2018] [Accepted: 01/23/2018] [Indexed: 06/07/2023]
Abstract
Replication factor C (RFC) is a conserved eukaryotic complex consisting of RFC1/2/3/4/5. It plays important roles in DNA replication and the cell cycle in yeast and fruit fly. However, it is not very clear how RFC subunits function in higher plants, except for the Arabidopsis (At) subunits AtRFC1 and AtRFC3. In this study, we investigated the functions of AtRFC4 and found that loss of function of AtRFC4 led to an early sporophyte lethality that initiated as early as the elongated zygote stage, all defective embryos arrested at the two- to four-cell embryo proper stage, and the endosperm possessed six to eight free nuclei. Complementation of rfc4-1/+ with AtRFC4 expression driven through the embryo-specific DD45pro and ABI3pro or the endosperm-specific FIS2pro could not completely restore the defective embryo or endosperm, whereas a combination of these three promoters in rfc4-1/+ enabled the aborted ovules to develop into viable seeds. This suggests that AtRFC4 functions simultaneously in endosperm and embryo and that the proliferation of endosperm is critical for embryo maturation. Assays of DNA content in rfc4-1/+ verified that DNA replication was disrupted in endosperm and embryo, resulting in blocked mitosis. Moreover, we observed a decreased proportion of late S-phase and M-phase cells in the rfc4-1/-FIS2;DD45;ABI3pro::AtRFC4 seedlings, suggesting that incomplete DNA replication triggered cell cycle arrest in cells of the root apical meristem. Therefore, we conclude that AtRFC4 is a crucial gene for DNA replication.
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Affiliation(s)
- Jie Qian
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Yueyue Chen
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Ying Hu
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Yingtian Deng
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Yang Liu
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Gang Li
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Wenxuan Zou
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Jie Zhao
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
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119
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Kalinowska K, Isono E. All roads lead to the vacuole-autophagic transport as part of the endomembrane trafficking network in plants. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:1313-1324. [PMID: 29165603 DOI: 10.1093/jxb/erx395] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 10/14/2017] [Indexed: 05/10/2023]
Abstract
Plants regulate their development and response to the changing environment by sensing and interpreting environmental signals. Intracellular trafficking pathways including endocytic-, vacuolar-, and autophagic trafficking are important for the various aspects of responses in plants. Studies in the last decade have shown that the autophagic transport pathway uses common key components of endomembrane trafficking as well as specific regulators. A number of factors previously described for their function in endosomal trafficking have been discovered to be involved in the regulation of autophagy in plants. These include conserved endocytic machineries, such as the endosomal sorting complex required for transport (ESCRT), subunits of the HOPS and exocyst complexes, SNAREs, and RAB GTPases as well as plant-specific proteins. Defects in these factors have been shown to cause impairment of autophagosome formation, transport, fusion, and degradation, suggesting crosstalk between autophagy and other intracellular trafficking processes. In this review, we focus mainly on possible functions of endosomal trafficking components in autophagy.
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120
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Romero-Barrios N, Vert G. Proteasome-independent functions of lysine-63 polyubiquitination in plants. THE NEW PHYTOLOGIST 2018; 217:995-1011. [PMID: 29194634 DOI: 10.1111/nph.14915] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 10/12/2017] [Indexed: 05/21/2023]
Abstract
Contents Summary 995 I. Introduction 995 II. The plant Ub machinery 996 III. From Ub to Ub linkage types in plants 997 IV. Increasing analytical resolution for K63 polyUb in plants 998 V. How to build K63 polyUb chains? 998 VI. Cellular roles of K63 polyUb in plants 999 VII. Physiological roles of K63 polyUb in plants 1004 VIII. Future perspectives: towards the next level of the Ub code 1006 Acknowledgements 1006 References 1007 SUMMARY: Ubiquitination is a post-translational modification essential for the regulation of eukaryotic proteins, having an impact on protein fate, function, localization or activity. What originally appeared to be a simple system to regulate protein turnover by the 26S proteasome is now known to be the most intricate regulatory process cells have evolved. Ubiquitin can be arranged in countless chain assemblies, triggering various cellular outcomes. Polyubiquitin chains using lysine-63 from ubiquitin represent the second most abundant type of ubiquitin modification. Recent studies have exposed their common function in proteasome-independent functions in non-plant model organisms. The existence of lysine-63 polyubiquitination in plants is, however, only just emerging. In this review, we discuss the recent advances on the characterization of ubiquitin chains and the molecular mechanisms driving the formation of lysine-63-linked ubiquitin modifications. We provide an overview of the roles associated with lysine-63 polyubiquitination in plant cells in the light of what is known in non-plant models. Finally, we review the crucial roles of lysine-63 polyubiquitin-dependent processes in plant growth, development and responses to environmental conditions.
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Affiliation(s)
- Natali Romero-Barrios
- Institute for Integrative Biology of the Cell (I2BC), CNRS/CEA/Univ. Paris Sud, Université Paris-Saclay, Gif-sur-Yvette, 91198, France
| | - Grégory Vert
- Institute for Integrative Biology of the Cell (I2BC), CNRS/CEA/Univ. Paris Sud, Université Paris-Saclay, Gif-sur-Yvette, 91198, France
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121
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Liu F, Hu W, Vierstra RD. The Vacuolar Protein Sorting-38 Subunit of the Arabidopsis Phosphatidylinositol-3-Kinase Complex Plays Critical Roles in Autophagy, Endosome Sorting, and Gravitropism. FRONTIERS IN PLANT SCIENCE 2018; 9:781. [PMID: 29967628 PMCID: PMC6016017 DOI: 10.3389/fpls.2018.00781] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 05/23/2018] [Indexed: 05/02/2023]
Abstract
The family of phosphatidylinositols (PtdIns) plays essential roles in membrane identity and intracellular trafficking events. In animals and yeast, PtdIn-3-phosphate, which is particularly important for endosomal sorting, lysosomal/vacuolar transport and autophagy, is assembled by two conserved kinase complexes comprised of the catalytic VACUOLAR PROTEIN SORTING (VPS)-34 subunit, along with VPS15, AUTOPHAGY-RELATED (ATG)-6, and either ATG14 (complex I) or VPS38 (complex II). Here, we describe the Arabidopsis ortholog of VPS38 and show by interaction assays that it assembles into a tetrameric PtdIn-3 kinase complex II. Plants missing VPS38 are viable but have dampened pollen germination and heightened seed abortion, and display a dwarf rosette phenotype, with defects in leaf and vascular development and sucrose sensing. vps38 seeds accumulate irregular protein storage vesicles and suppress processing of storage proteins into their mature forms. Consistent with a role for PtdIn-3-phosphate in autophagy, vps38 mutants are hypersensitive to nitrogen and fixed-carbon starvation and show reduced autophagic transport of cargo into vacuoles. vps38 seedlings also have dampened root gravitropism, which is underpinned by aberrant vectoral auxin transport likely caused by defects in plasma membrane/endosome cycling of the PIN-FORMED family of auxin transporters necessary for asymmetric cell elongation. Collectively, this study places VPS38 and its class-III PtdIn-3 kinase complex at the nexus of numerous endosomal trafficking events important to plant growth and development.
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Affiliation(s)
- Fen Liu
- Department of Biology, Washington University in St. Louis, St. Louis, MO, United States
- South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Weiming Hu
- Department of Biology, Washington University in St. Louis, St. Louis, MO, United States
| | - Richard D. Vierstra
- Department of Biology, Washington University in St. Louis, St. Louis, MO, United States
- *Correspondence: Richard D. Vierstra,
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122
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Cui Y, He Y, Cao W, Gao J, Jiang L. The Multivesicular Body and Autophagosome Pathways in Plants. FRONTIERS IN PLANT SCIENCE 2018; 9:1837. [PMID: 30619408 PMCID: PMC6299029 DOI: 10.3389/fpls.2018.01837] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 11/27/2018] [Indexed: 05/03/2023]
Abstract
In eukaryotic cells, the endomembrane system consists of multiple membrane-bound organelles, which play essential roles in the precise transportation of various cargo proteins. In plant cells, vacuoles are regarded as the terminus of catabolic pathways whereas the selection and transport of vacuolar cargoes are mainly mediated by two types of organelles, multivesicular bodies (MVBs) also termed prevacuolar compartments (PVCs) and autophagosomes. MVBs are single-membrane bound organelles with intraluminal vesicles and mediate the transport between the trans-Golgi network (TGN) and vacuoles, while autophagosomes are double-membrane bound organelles, which mediate cargo delivery to the vacuole for degradation and recycling during autophagy. Great progress has been achieved recently in identification and characterization of the conserved and plant-unique regulators involved in the MVB and autophagosome pathways. In this review, we present an update on the current knowledge of these key regulators and pay special attention to their conserved protein domains. In addition, we discuss the possible interplay between the MVB and autophagosome pathways in regulating vacuolar degradation in plants.
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Affiliation(s)
- Yong Cui
- Centre for Cell and Developmental Biology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
- State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong
- *Correspondence: Yong Cui, Liwen Jiang,
| | - Yilin He
- Centre for Cell and Developmental Biology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
- State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Wenhan Cao
- Centre for Cell and Developmental Biology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
- State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Jiayang Gao
- Centre for Cell and Developmental Biology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
- State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Liwen Jiang
- Centre for Cell and Developmental Biology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
- State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong
- The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, China
- *Correspondence: Yong Cui, Liwen Jiang,
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Wang Y, Yang L, Tang Y, Tang R, Jing Y, Zhang C, Zhang B, Li X, Cui Y, Zhang C, Shi J, Zhao F, Lan W, Luan S. Arabidopsis choline transporter-like 1 (CTL1) regulates secretory trafficking of auxin transporters to control seedling growth. PLoS Biol 2017; 15:e2004310. [PMID: 29283991 PMCID: PMC5746207 DOI: 10.1371/journal.pbio.2004310] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 11/21/2017] [Indexed: 01/04/2023] Open
Abstract
Auxin controls a myriad of plant developmental processes and plant response to environmental conditions. Precise trafficking of auxin transporters is essential for auxin homeostasis in plants. Here, we report characterization of Arabidopsis CTL1, which controls seedling growth and apical hook development by regulating intracellular trafficking of PIN-type auxin transporters. The CTL1 gene encodes a choline transporter-like protein with an expression pattern highly correlated with auxin distribution and is enriched in shoot and root apical meristems, lateral root primordia, the vascular system, and the concave side of the apical hook. The choline transporter-like 1 (CTL1) protein is localized to the trans-Golgi network (TGN), prevacuolar compartment (PVC), and plasma membrane (PM). Disruption of CTL1 gene expression alters the trafficking of 2 auxin efflux transporters—Arabidopsis PM-located auxin efflux transporter PIN-formed 1 (PIN1) and Arabidopsis PM-located auxin efflux transporter PIN-formed 3 (PIN3)—to the PM, thereby affecting auxin distribution and plant growth and development. We further found that phospholipids, sphingolipids, and other membrane lipids were significantly altered in the ctl1 mutant, linking CTL1 function to lipid homeostasis. We propose that CTL1 regulates protein sorting from the TGN to the PM through its function in lipid homeostasis. Auxin, a plant hormone, controls many aspects of plant growth and development. The precise transport and distribution of auxin hold the key to its function. A number of transport proteins are known to be involved in auxin translocation, and the PIN proteins, which are an integral part of membranes in plants, play a pivotal role in this process. Several PIN proteins are localized in the plasma membrane to mediate auxin efflux from cells, but their regulation is not well known. In this report, we analyze the role of a choline transport protein, choline transporter-like 1 (CTL1), and find that it controls the trafficking of Arabidopsis PM-located auxin efflux transporter PIN-formed 1 (PIN1) and Arabidopsis PM-located auxin efflux transporter PIN-formed 3 (PIN3) to the plasma membrane, thereby regulating auxin distribution during plant growth and development. In addition, we show that CTL1 has a role in lipid homeostasis in the membrane; thus, these findings provide a mechanistic link between choline transport, lipid homeostasis, and vesicle trafficking in plants. We conclude that CTL1 is a new factor in secretory protein sorting and that this finding contributes to the understanding of not only auxin distribution in plants but also protein trafficking in general.
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Affiliation(s)
- Yuan Wang
- State Key Laboratory for Pharmaceutical Biotechnology, Nanjing University-Nanjing Forestry University Joint Institute for Plant Molecular Biology, College of Life Sciences, Nanjing University, Nanjing, China
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, California, United States of America
- College of Life Sciences, Northwest University, Xi’an, Shanxi, China
| | - Lei Yang
- State Key Laboratory for Pharmaceutical Biotechnology, Nanjing University-Nanjing Forestry University Joint Institute for Plant Molecular Biology, College of Life Sciences, Nanjing University, Nanjing, China
| | - Yumei Tang
- State Key Laboratory for Pharmaceutical Biotechnology, Nanjing University-Nanjing Forestry University Joint Institute for Plant Molecular Biology, College of Life Sciences, Nanjing University, Nanjing, China
| | - Renjie Tang
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, California, United States of America
| | - Yanping Jing
- State Key Laboratory for Pharmaceutical Biotechnology, Nanjing University-Nanjing Forestry University Joint Institute for Plant Molecular Biology, College of Life Sciences, Nanjing University, Nanjing, China
| | - Chi Zhang
- State Key Laboratory for Pharmaceutical Biotechnology, Nanjing University-Nanjing Forestry University Joint Institute for Plant Molecular Biology, College of Life Sciences, Nanjing University, Nanjing, China
| | - Bin Zhang
- State Key Laboratory for Pharmaceutical Biotechnology, Nanjing University-Nanjing Forestry University Joint Institute for Plant Molecular Biology, College of Life Sciences, Nanjing University, Nanjing, China
| | - Xiaojuan Li
- Key Laboratory for Genetics and Breeding of Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
| | - Yaning Cui
- Key Laboratory for Genetics and Breeding of Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
| | - Chunhua Zhang
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana, United States of America
| | - Jisen Shi
- Nanjing University–Nanjing Forestry University Joint Institute for Plant Molecular Biology, Key Laboratory of Forest Genetics and Biotechnology, Nanjing Forestry University, Nanjing, China
| | - Fugeng Zhao
- State Key Laboratory for Pharmaceutical Biotechnology, Nanjing University-Nanjing Forestry University Joint Institute for Plant Molecular Biology, College of Life Sciences, Nanjing University, Nanjing, China
| | - Wenzhi Lan
- State Key Laboratory for Pharmaceutical Biotechnology, Nanjing University-Nanjing Forestry University Joint Institute for Plant Molecular Biology, College of Life Sciences, Nanjing University, Nanjing, China
- * E-mail: (WL); (SL)
| | - Sheng Luan
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, California, United States of America
- * E-mail: (WL); (SL)
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124
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Dubeaux G, Vert G. Zooming into plant ubiquitin-mediated endocytosis. CURRENT OPINION IN PLANT BIOLOGY 2017; 40:56-62. [PMID: 28756333 DOI: 10.1016/j.pbi.2017.07.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 06/29/2017] [Accepted: 07/11/2017] [Indexed: 05/21/2023]
Abstract
Endocytosis in plants plays an essential role, not only for basic cellular functions but also for growth, development, and environmental responses. Over the past few years, ubiquitin emerged as a major signal triggering the removal of plasma membrane proteins from the cell surface and promoting their vacuolar targeting. Detailed genetic, biochemical and imaging studies have provided initial insights into the precise mechanisms and roles of ubiquitin-mediated endocytosis in plants. Here, we summarize the present state of knowledge about the machinery involved in plant ubiquitin-mediated endocytosis and how this is coordinated in time and space to control the internalization and the endosomal sorting of endocytosed proteins.
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Affiliation(s)
- Guillaume Dubeaux
- Institute for Integrative Biology of the Cell (I2BC), CNRS/CEA/Univ. Paris Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette, France
| | - Grégory Vert
- Institute for Integrative Biology of the Cell (I2BC), CNRS/CEA/Univ. Paris Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette, France.
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125
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Noack LC, Jaillais Y. Precision targeting by phosphoinositides: how PIs direct endomembrane trafficking in plants. CURRENT OPINION IN PLANT BIOLOGY 2017; 40:22-33. [PMID: 28734137 DOI: 10.1016/j.pbi.2017.06.017] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 06/19/2017] [Accepted: 06/27/2017] [Indexed: 05/18/2023]
Abstract
Each phosphoinositide (PI, also known as phosphatidylinositol phosphate, polyphosphoinositide, PtdInsP or PIP) species is partitioned in the endomembrane system and thereby contributes to the identity of membrane compartments. However, membranes are in constant flux within this system, which raises the questions of how the spatiotemporal pattern of phosphoinositides is established and maintained within the cell. Here, we review the general mechanisms by which phosphoinositides and membrane trafficking feedbacks on each other to regulate cellular patterning. We then use the specific examples of polarized trafficking, endosomal sorting and vacuolar biogenesis to illustrate these general concepts.
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Affiliation(s)
- Lise C Noack
- Laboratoire Reproduction et Développement des Plantes, Univ Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRA, F-69342 Lyon, France
| | - Yvon Jaillais
- Laboratoire Reproduction et Développement des Plantes, Univ Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRA, F-69342 Lyon, France.
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126
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Isono E, Kalinowska K. ESCRT-dependent degradation of ubiquitylated plasma membrane proteins in plants. CURRENT OPINION IN PLANT BIOLOGY 2017; 40:49-55. [PMID: 28753460 DOI: 10.1016/j.pbi.2017.07.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 07/07/2017] [Accepted: 07/11/2017] [Indexed: 05/20/2023]
Abstract
To control the abundance of plasma membrane receptors and transporters is crucial for proper perception and response to extracellular signals from surrounding cells and the environment. Posttranslational modification of plasma membrane proteins, especially ubiquitin conjugation or ubiquitylation, is key for the determination of stability for many transmembrane proteins localized on the cell surface. The targeted degradation is ensured by a complex network of proteins among which the endosomal sorting complex required for transport (ESCRT) plays a central role. This review focuses on progresses made in recent years on the understanding of the function of the ESCRT machinery in the degradation of ubiquitylated plasma membrane proteins in plants.
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Affiliation(s)
- Erika Isono
- Department of Plant Sciences, School of Life Sciences Weihenstephan, Technical University of Munich, Emil-Ramann-Str. 8, 85456 Freising, Germany; Department of Biology, University of Konstanz, Universtitätsstrasse 10, 78464 Konstanz, Germany.
| | - Kamila Kalinowska
- Department of Plant Sciences, School of Life Sciences Weihenstephan, Technical University of Munich, Emil-Ramann-Str. 8, 85456 Freising, Germany
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127
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Gao C, Zhuang X, Shen J, Jiang L. Plant ESCRT Complexes: Moving Beyond Endosomal Sorting. TRENDS IN PLANT SCIENCE 2017; 22:986-998. [PMID: 28867368 DOI: 10.1016/j.tplants.2017.08.003] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 08/01/2017] [Accepted: 08/09/2017] [Indexed: 05/19/2023]
Abstract
The endosomal sorting complex required for transport (ESCRT) machinery is an ancient system that deforms membrane and severs membrane necks from the inside. Extensive evidence has accumulated to demonstrate the conserved functions of plant ESCRTs in multivesicular body (MVB) biogenesis and MVB-mediated membrane protein sorting. In addition, recent exciting findings have uncovered unique plant ESCRT components and point to emerging roles for plant ESCRTs in non-endosomal sorting events such as autophagy, cytokinesis, and viral replication. Plant-specific processes, such as abscisic acid (ABA) signaling and chloroplast turnover, provide further evidence for divergences in the functions of plant ESCRTs during evolution. We summarize the multiple roles and current working models for plant ESCRT machinery and speculate on future ESCRT studies in the plant field.
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Affiliation(s)
- Caiji Gao
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University (SCNU), Guangzhou 510631, China; These authors contributed equally to this work
| | - Xiaohong Zhuang
- Centre for Cell and Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong (CUHK), Shatin, New Territories, Hong Kong, China; These authors contributed equally to this work
| | - Jinbo Shen
- Centre for Cell and Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong (CUHK), Shatin, New Territories, Hong Kong, China; These authors contributed equally to this work
| | - Liwen Jiang
- Centre for Cell and Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong (CUHK), Shatin, New Territories, Hong Kong, China.
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128
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Yu F, Xie Q. Non-26S Proteasome Endomembrane Trafficking Pathways in ABA Signaling. TRENDS IN PLANT SCIENCE 2017; 22:976-985. [PMID: 28919033 DOI: 10.1016/j.tplants.2017.08.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 08/24/2017] [Accepted: 08/25/2017] [Indexed: 05/26/2023]
Abstract
The phytohormone abscisic acid (ABA) is a vital endogenous messenger that regulates diverse physiological processes in plants. The regulation of ABA signaling has been well studied at both the transcriptional and translational levels. Post-translational modification of key regulators in ABA signaling by the 26S ubiquitin proteasome pathway is well known. Recently, increasing evidence demonstrates that atypical turnover of key regulators by the endocytic trafficking pathway and autophagy also play vital roles in ABA perception, signaling, and action. We summarize and synthesize here recent findings in the field of ABA signaling.
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Affiliation(s)
- Feifei Yu
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Number 1 West Beichen Road, Chaoyang District, Beijing 100101, PR China
| | - Qi Xie
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Number 1 West Beichen Road, Chaoyang District, Beijing 100101, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
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129
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Horner DS, Pasini ME, Beltrame M, Mastrodonato V, Morelli E, Vaccari T. ESCRT genes and regulation of developmental signaling. Semin Cell Dev Biol 2017; 74:29-39. [PMID: 28847745 DOI: 10.1016/j.semcdb.2017.08.038] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 08/06/2017] [Accepted: 08/18/2017] [Indexed: 11/30/2022]
Abstract
ESCRT (Endosomal Sorting Complex Required for Transport) proteins have been shown to control an increasing number of membrane-associated processes. Some of these, and prominently regulation of receptor trafficking, profoundly shape signal transduction. Evidence in fungi, plants and multiple animal models support the emerging concept that ESCRTs are main actors in coordination of signaling with the changes in cells and tissues occurring during development and homeostasis. Consistent with their pleiotropic function, ESCRTs are regulated in multiple ways to tailor signaling to developmental and homeostatic needs. ESCRT activity is crucial to correct execution of developmental programs, especially at key transitions, allowing eukaryotes to thrive and preventing appearance of congenital defects.
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Affiliation(s)
- David S Horner
- Dipartimento di Bioscienze, Universita' degli Studi di Milano, Via Celoria 26, 20133 Milano, Italy
| | - Maria E Pasini
- Dipartimento di Bioscienze, Universita' degli Studi di Milano, Via Celoria 26, 20133 Milano, Italy
| | - Monica Beltrame
- Dipartimento di Bioscienze, Universita' degli Studi di Milano, Via Celoria 26, 20133 Milano, Italy
| | - Valeria Mastrodonato
- IFOM, The FIRC Institute of Molecular Oncology, Via Adamello 16, 20139 Milano, Italy
| | - Elena Morelli
- IFOM, The FIRC Institute of Molecular Oncology, Via Adamello 16, 20139 Milano, Italy
| | - Thomas Vaccari
- Dipartimento di Bioscienze, Universita' degli Studi di Milano, Via Celoria 26, 20133 Milano, Italy; IFOM, The FIRC Institute of Molecular Oncology, Via Adamello 16, 20139 Milano, Italy.
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130
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Nagel MK, Kalinowska K, Vogel K, Reynolds GD, Wu Z, Anzenberger F, Ichikawa M, Tsutsumi C, Sato MH, Kuster B, Bednarek SY, Isono E. Arabidopsis SH3P2 is an ubiquitin-binding protein that functions together with ESCRT-I and the deubiquitylating enzyme AMSH3. Proc Natl Acad Sci U S A 2017; 114:E7197-E7204. [PMID: 28784794 PMCID: PMC5576839 DOI: 10.1073/pnas.1710866114] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Clathrin-mediated endocytosis of plasma membrane proteins is an essential regulatory process that controls plasma membrane protein abundance and is therefore important for many signaling pathways, such as hormone signaling and biotic and abiotic stress responses. On endosomal sorting, plasma membrane proteins maybe recycled or targeted for vacuolar degradation, which is dependent on ubiquitin modification of the cargos and is driven by the endosomal sorting complexes required for transport (ESCRTs). Components of the ESCRT machinery are highly conserved among eukaryotes, but homologs of ESCRT-0 that are responsible for recognition and concentration of ubiquitylated proteins are absent in plants. Recently several ubiquitin-binding proteins have been identified that serve in place of ESCRT-0; however, their function in ubiquitin recognition and endosomal trafficking is not well understood yet. In this study, we identified Src homology-3 (SH3) domain-containing protein 2 (SH3P2) as a ubiquitin- and ESCRT-I-binding protein that functions in intracellular trafficking. SH3P2 colocalized with clathrin light chain-labeled punctate structures and interacted with clathrin heavy chain in planta, indicating a role for SH3P2 in clathrin-mediated endocytosis. Furthermore, SH3P2 cofractionates with clathrin-coated vesicles (CCVs), suggesting that it associates with CCVs in planta Mutants of SH3P2 and VPS23 genetically interact, suggesting that they could function in the same pathway. Based on these results, we suggest a role of SH3P2 as an ubiquitin-binding protein that binds and transfers ubiquitylated proteins to the ESCRT machinery.
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Affiliation(s)
- Marie-Kristin Nagel
- Chair of Plant Physiology and Biochemistry, Department of Biology, University of Konstanz, 78457 Konstanz, Germany
- Chair of Plant Systems Biology, School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising, Germany
| | - Kamila Kalinowska
- Chair of Plant Systems Biology, School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising, Germany
| | - Karin Vogel
- Chair of Plant Physiology and Biochemistry, Department of Biology, University of Konstanz, 78457 Konstanz, Germany
- Chair of Plant Systems Biology, School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising, Germany
| | - Gregory D Reynolds
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706
| | - Zhixiang Wu
- Chair of Proteomics and Bioanalytics, School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising, Germany
| | - Franziska Anzenberger
- Chair of Plant Systems Biology, School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising, Germany
| | - Mie Ichikawa
- Department of Life and Environmental Sciences, Kyoto Prefectural University, 606-0823 Kyoto, Japan
| | - Chie Tsutsumi
- Department of Botany, National Museum of Nature and Science, 305-0005 Tsukuba, Japan
| | - Masa H Sato
- Department of Life and Environmental Sciences, Kyoto Prefectural University, 606-0823 Kyoto, Japan
| | - Bernhard Kuster
- Chair of Proteomics and Bioanalytics, School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising, Germany
| | | | - Erika Isono
- Chair of Plant Physiology and Biochemistry, Department of Biology, University of Konstanz, 78457 Konstanz, Germany;
- Chair of Plant Systems Biology, School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising, Germany
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131
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Sutipatanasomboon A, Herberth S, Alwood EG, Häweker H, Müller B, Shahriari M, Zienert AY, Marin B, Robatzek S, Praefcke GJK, Ayscough KR, Hülskamp M, Schellmann S. Disruption of the plant-specific CFS1 gene impairs autophagosome turnover and triggers EDS1-dependent cell death. Sci Rep 2017; 7:8677. [PMID: 28819237 PMCID: PMC5561093 DOI: 10.1038/s41598-017-08577-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 07/13/2017] [Indexed: 11/23/2022] Open
Abstract
Cell death, autophagy and endosomal sorting contribute to many physiological, developmental and immunological processes in plants. They are mechanistically interconnected and interdependent, but the molecular basis of their mutual regulation has only begun to emerge in plants. Here, we describe the identification and molecular characterization of CELL DEATH RELATED ENDOSOMAL FYVE/SYLF PROTEIN 1 (CFS1). The CFS1 protein interacts with the ENDOSOMAL SORTING COMPLEX REQUIRED FOR TRANSPORT I (ESCRT-I) component ELCH (ELC) and is localized at ESCRT-I-positive late endosomes likely through its PI3P and actin binding SH3YL1 Ysc84/Lsb4p Lsb3p plant FYVE (SYLF) domain. Mutant alleles of cfs1 exhibit auto-immune phenotypes including spontaneous lesions that show characteristics of hypersensitive response (HR). Autoimmunity in cfs1 is dependent on ENHANCED DISEASE SUSCEPTIBILITY 1 (EDS1)-mediated effector-triggered immunity (ETI) but independent from salicylic acid. Additionally, cfs1 mutants accumulate the autophagy markers ATG8 and NBR1 independently from EDS1. We hypothesize that CFS1 acts at the intersection of autophagosomes and endosomes and contributes to cellular homeostasis by mediating autophagosome turnover.
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Affiliation(s)
| | - Stefanie Herberth
- Botanik III, Biocenter, Universtiy of Cologne, Zülpicher Str. 47B, 50674, Cologne, Germany
| | - Ellen G Alwood
- Department of Biomedical Science, The University of Sheffield, Western Bank Sheffield, S10 2TN, United Kingdom
| | - Heidrun Häweker
- The Sainsbury Laboratory, Norwich Research Park, Norwich, NR4 7UH, United Kingdom
| | - Britta Müller
- Botanik III, Biocenter, Universtiy of Cologne, Zülpicher Str. 47B, 50674, Cologne, Germany
| | - Mojgan Shahriari
- Botanik III, Biocenter, Universtiy of Cologne, Zülpicher Str. 47B, 50674, Cologne, Germany
- Institut für Biologie II, University of Freiburg, Schänzlestrasse 1, 79104, Freiburg i. Br., Germany
| | - Anke Y Zienert
- Institut für Genetik, Universtiy of Cologne, Zülpicher Str. 47A, 50674, Cologne, Germany
| | - Birger Marin
- Botanik I, Biocenter, Universtiy of Cologne, Zülpicher Str. 47B, 50674, Cologne, Germany
| | - Silke Robatzek
- The Sainsbury Laboratory, Norwich Research Park, Norwich, NR4 7UH, United Kingdom
| | - Gerrit J K Praefcke
- Institut für Genetik, Universtiy of Cologne, Zülpicher Str. 47A, 50674, Cologne, Germany
- Division of Haematology/Transfusion Medicine, Paul-Ehrlich-Institut, Federal Institute for Vaccines and Biomedicines, Paul-Ehrlich-Str. 51-59, 63225, Langen, Germany
| | - Kathryn R Ayscough
- Department of Biomedical Science, The University of Sheffield, Western Bank Sheffield, S10 2TN, United Kingdom
| | - Martin Hülskamp
- Botanik III, Biocenter, Universtiy of Cologne, Zülpicher Str. 47B, 50674, Cologne, Germany.
| | - Swen Schellmann
- Botanik III, Biocenter, Universtiy of Cologne, Zülpicher Str. 47B, 50674, Cologne, Germany.
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132
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Lefebvre C, Legouis R, Culetto E. ESCRT and autophagies: Endosomal functions and beyond. Semin Cell Dev Biol 2017; 74:21-28. [PMID: 28807884 DOI: 10.1016/j.semcdb.2017.08.014] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 07/27/2017] [Accepted: 08/04/2017] [Indexed: 12/20/2022]
Abstract
ESCRT (endosomal sorting complex required for transport) machinery has been initially identified for its role during endocytosis, which allows membrane proteins and lipids to be degraded in the lysosome. ESCRT function is required to form intraluminal vesicles permitting internalization of cytosolic components or membrane embedded cargoes and promoting endosome maturation. ESCRT machinery also contributes to multiple key cell mechanisms in which it reshapes membranes. In addition, ESCRT actively participates in different types of autophagy processes for degrading cytosolic components, such as endosomal microautophagy and macroautophagy. During macroautophagy, ESCRT promotes formation of multivesicular bodies, which can fuse with autophagosomes to generate amphisomes. This latter fusion probably brings to autophagosomes key membrane molecules necessary for the subsequent fusion with lysosomes. Interestingly, during macroautophagy, ESCRT proteins could be involved in non-canonical functions such as vesicle tethering or phagophore membrane sealing. Additionally, ESCRT subunits could directly interact with key autophagy related proteins to build a closer connection between endocytosis and autophagy pathways.
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Affiliation(s)
- Christophe Lefebvre
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91198, Gif-sur-Yvette Cedex, France
| | - Renaud Legouis
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91198, Gif-sur-Yvette Cedex, France.
| | - Emmanuel Culetto
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91198, Gif-sur-Yvette Cedex, France.
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133
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New advances in autophagy in plants: Regulation, selectivity and function. Semin Cell Dev Biol 2017; 80:113-122. [PMID: 28734771 DOI: 10.1016/j.semcdb.2017.07.018] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 07/08/2017] [Accepted: 07/15/2017] [Indexed: 01/01/2023]
Abstract
Autophagy is a major and conserved pathway for delivering unwanted proteins or damaged organelles to the vacuole for degradation and recycling. In plants, it functions as a housekeeping process to maintain cellular homeostasis under normal conditions and is induced by stress and senescence; it thus plays important roles in development, stress tolerance and metabolism. Autophagy can both execute bulk degradation and be highly selective in targeting cargos under specific environmental conditions or during certain developmental processes. Here, we review recent research on autophagy in plants, and discuss new insights into its core mechanism, regulation, selectivity and physiological roles. Potential future directions are also highlighted.
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134
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Krüger F, Schumacher K. Pumping up the volume - vacuole biogenesis in Arabidopsis thaliana. Semin Cell Dev Biol 2017; 80:106-112. [PMID: 28694113 DOI: 10.1016/j.semcdb.2017.07.008] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 07/06/2017] [Accepted: 07/06/2017] [Indexed: 01/05/2023]
Abstract
Plant architecture follows the need to collect CO2, solar energy, water and mineral nutrients via large surface areas. It is by the presence of a central vacuole that fills much of the cell volume that plants manage to grow at low metabolic cost. In addition vacuoles buffer the fluctuating supply of essential nutrients and help to detoxify the cytosol when plants are challenged by harmful molecules. Despite their large size and multiple important functions, our knowledge of vacuole biogenesis and the machinery underlying their amazing dynamics is still fragmentary. In this review, we try to reconcile past and present models for vacuole biogenesis with the current knowledge of multiple parallel vacuolar trafficking pathways and the molecular machineries driving membrane fusion and organelle shape.
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Affiliation(s)
- Falco Krüger
- Department of Plant Developmental Biology, Centre for Organismal Studies, Heidelberg University, DE-69120 Heidelberg, Germany
| | - Karin Schumacher
- Department of Plant Developmental Biology, Centre for Organismal Studies, Heidelberg University, DE-69120 Heidelberg, Germany.
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135
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Konopka-Postupolska D, Clark G. Annexins as Overlooked Regulators of Membrane Trafficking in Plant Cells. Int J Mol Sci 2017; 18:E863. [PMID: 28422051 PMCID: PMC5412444 DOI: 10.3390/ijms18040863] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Revised: 04/03/2017] [Accepted: 04/06/2017] [Indexed: 12/11/2022] Open
Abstract
Annexins are an evolutionary conserved superfamily of proteins able to bind membrane phospholipids in a calcium-dependent manner. Their physiological roles are still being intensively examined and it seems that, despite their general structural similarity, individual proteins are specialized toward specific functions. However, due to their general ability to coordinate membranes in a calcium-sensitive fashion they are thought to participate in membrane flow. In this review, we present a summary of the current understanding of cellular transport in plant cells and consider the possible roles of annexins in different stages of vesicular transport.
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Affiliation(s)
- Dorota Konopka-Postupolska
- Plant Biochemistry Department, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw 02-106, Poland.
| | - Greg Clark
- Molecular, Cell, and Developmental Biology, University of Texas, Austin, TX 78712, USA.
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136
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Phosphatidylinositol 3-phosphate-binding protein AtPH1 controls the localization of the metal transporter NRAMP1 in Arabidopsis. Proc Natl Acad Sci U S A 2017; 114:E3354-E3363. [PMID: 28373552 DOI: 10.1073/pnas.1702975114] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
"Too much of a good thing" perfectly describes the dilemma that living organisms face with metals. The tight control of metal homeostasis in cells depends on the trafficking of metal transporters between membranes of different compartments. However, the mechanisms regulating the location of transport proteins are still largely unknown. Developing Arabidopsis thaliana seedlings require the natural resistance-associated macrophage proteins (NRAMP3 and NRAMP4) transporters to remobilize iron from seed vacuolar stores and thereby acquire photosynthetic competence. Here, we report that mutations in the pleckstrin homology (PH) domain-containing protein AtPH1 rescue the iron-deficient phenotype of nramp3nramp4 Our results indicate that AtPH1 binds phosphatidylinositol 3-phosphate (PI3P) in vivo and acts in the late endosome compartment. We further show that loss of AtPH1 function leads to the mislocalization of the metal uptake transporter NRAMP1 to the vacuole, providing a rationale for the reversion of nramp3nramp4 phenotypes. This work identifies a PH domain protein as a regulator of plant metal transporter localization, providing evidence that PH domain proteins may be effectors of PI3P for protein sorting.
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137
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Klink VP, Sharma K, Pant SR, McNeece B, Niraula P, Lawrence GW. Components of the SNARE-containing regulon are co-regulated in root cells undergoing defense. PLANT SIGNALING & BEHAVIOR 2017; 12:e1274481. [PMID: 28010187 PMCID: PMC5351740 DOI: 10.1080/15592324.2016.1274481] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 12/14/2016] [Accepted: 12/15/2016] [Indexed: 05/23/2023]
Abstract
The term regulon has been coined in the genetic model plant Arabidopsis thaliana, denoting a structural and physiological defense apparatus defined genetically through the identification of the penetration (pen) mutants. The regulon is composed partially by the soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor (SNARE) syntaxin PEN1. PEN1 has homology to a Saccharomyces cerevisae gene that regulates a Secretion (Sec) protein, Suppressor of Sec 1 (Sso1p). The regulon is also composed of the β-glucosidase (PEN2) and an ATP binding cassette (ABC) transporter (PEN3). While important in inhibiting pathogen infection, limited observations have been made regarding the transcriptional regulation of regulon genes until now. Experiments made using the model agricultural Glycine max (soybean) have identified co-regulated gene expression of regulon components. The results explain the observation of hundreds of genes expressed specifically in the root cells undergoing the natural process of defense. Data regarding additional G. max genes functioning within the context of the regulon are presented here, including Sec 14, Sec 4 and Sec 23. Other examined G. max homologs of membrane fusion genes include an endosomal bromo domain-containing protein1 (Bro1), syntaxin6 (SYP6), SYP131, SYP71, SYP8, Bet1, coatomer epsilon (ϵ-COP), a coatomer zeta (ζ-COP) paralog and an ER to Golgi component (ERGIC) protein. Furthermore, the effectiveness of biochemical pathways that would function within the context of the regulon ave been examined, including xyloglucan xylosyltransferase (XXT), reticuline oxidase (RO) and galactinol synthase (GS). The experiments have unveiled the importance of the regulon during defense in the root and show how the deposition of callose relates to the process.
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Affiliation(s)
- Vincent P. Klink
- Department of Biological Sciences, Mississippi State University, Mississippi State, MS, USA
| | - Keshav Sharma
- Department of Biological Sciences, Mississippi State University, Mississippi State, MS, USA
| | - Shankar R. Pant
- Department of Biological Sciences, Mississippi State University, Mississippi State, MS, USA
| | - Brant McNeece
- Department of Biological Sciences, Mississippi State University, Mississippi State, MS, USA
| | - Prakash Niraula
- Department of Biological Sciences, Mississippi State University, Mississippi State, MS, USA
| | - Gary W. Lawrence
- Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Mississippi State University, Mississippi State, MS, USA
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138
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ATG9 regulates autophagosome progression from the endoplasmic reticulum in Arabidopsis. Proc Natl Acad Sci U S A 2017; 114:E426-E435. [PMID: 28053229 DOI: 10.1073/pnas.1616299114] [Citation(s) in RCA: 166] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Autophagy is a conserved pathway for bulk degradation of cytoplasmic material by a double-membrane structure named the autophagosome. The initiation of autophagosome formation requires the recruitment of autophagy-related protein 9 (ATG9) vesicles to the preautophagosomal structure. However, the functional relationship between ATG9 vesicles and the phagophore is controversial in different systems, and the molecular function of ATG9 remains unknown in plants. Here, we demonstrate that ATG9 is essential for endoplasmic reticulum (ER)-derived autophagosome formation in plants. Through a combination of genetic, in vivo imaging and electron tomography approaches, we show that Arabidopsis ATG9 deficiency leads to a drastic accumulation of autophagosome-related tubular structures in direct membrane continuity with the ER upon autophagic induction. Dynamic analyses demonstrate a transient membrane association between ATG9 vesicles and the autophagosomal membrane during autophagy. Furthermore, trafficking of ATG18a is compromised in atg9 mutants during autophagy by forming extended tubules in a phosphatidylinositol 3-phosphate-dependent manner. Taken together, this study provides evidence for a pivotal role of ATG9 in regulating autophagosome progression from the ER membrane in Arabidopsis.
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139
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Yu F, Lou L, Tian M, Li Q, Ding Y, Cao X, Wu Y, Belda-Palazon B, Rodriguez PL, Yang S, Xie Q. ESCRT-I Component VPS23A Affects ABA Signaling by Recognizing ABA Receptors for Endosomal Degradation. MOLECULAR PLANT 2016; 9:1570-1582. [PMID: 27856401 DOI: 10.1016/j.molp.2016.11.002] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 10/07/2016] [Accepted: 11/05/2016] [Indexed: 05/03/2023]
Abstract
Recent discovery of PYR/PYL/RCAR-type abscisic acid (ABA) receptors has become one of most significant advances in plant science in the past decade. In mammals, endosomal sorting acts as an important pathway to downregulate different types of receptors, but its role in plant hormone signaling is poorly understood. Here, we report that an ubiquitin E2-like protein, VPS23A, which is a key component of ESCRT-I, negatively regulates ABA signaling. VPS23A has epistatic relationship with PYR/PYL/RCAR-type ABA receptors and disruption of VPS23A enhanced the activity of key kinase OST1 in the ABA signaling pathway under ABA treatment. Moreover, VPS23A interacts with PYR1/PYLs and K63-linked diubiquitin, and PYL4 possesses K63-linked ubiquitinated modification in vivo. Further analysis revealed that VPS23A affects the subcellular localization of PYR1 and the stability of PYL4. Taken together, our results suggest that VPS23A affects PYR1/PYL4 via vacuole-mediated degradation, providing an advanced understanding of both the turnover of ABA receptors and ESCRTs in plant hormone signaling.
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Affiliation(s)
- Feifei Yu
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Chaoyang District, Beijing 100101, P. R. China; College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Lijuan Lou
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Chaoyang District, Beijing 100101, P. R. China
| | - Miaomiao Tian
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Chaoyang District, Beijing 100101, P. R. China
| | - Qingliang Li
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Chaoyang District, Beijing 100101, P. R. China
| | - Yanglin Ding
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Xiaoqiang Cao
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Chaoyang District, Beijing 100101, P. R. China
| | - Yaorong Wu
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Chaoyang District, Beijing 100101, P. R. China
| | - Borja Belda-Palazon
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas-Universidad Politécnica de Valencia, 46022 Valencia, Spain
| | - Pedro L Rodriguez
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas-Universidad Politécnica de Valencia, 46022 Valencia, Spain
| | - Shuhua Yang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Qi Xie
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Chaoyang District, Beijing 100101, P. R. China.
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140
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Yang H, Liu J, Lin J, Deng L, Fan S, Guo Y, Sun F, Hua W. Overexpression of CHMP7 from rapeseed and Arabidopsis causes dwarfism and premature senescence in Arabidopsis. JOURNAL OF PLANT PHYSIOLOGY 2016; 204:16-26. [PMID: 27497741 DOI: 10.1016/j.jplph.2016.06.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 06/24/2016] [Accepted: 06/27/2016] [Indexed: 06/06/2023]
Abstract
Endosomal sorting complexes required for transport (ESCRT) are well known in mammalians and yeast and plays an essential role in the formation of multi-vesicular bodies. Accumulating evidence has shown that ESCRT proteins contribute to proper plant development. CHMP7 (charged multi-vesicular body protein 7) is an ESCRT-III-related protein and functions in the endosomal sorting pathway in humans. However, its function in plants has not been explored in detail. In this study, we isolate the putative homolog of CHMP7 from rapeseed, BnCHMP7, which contains eight exons and encodes a protein consisting of 423 amino acid residues. Compared with the wild-type, overexpression of BnCHMP7 in Arabidopsis disturbs plant growth and decreases seed yield. Moreover, the transgenic plants also display early leaf senescence and hypersensitivity to dark treatment due to defects in autophagic degradation. Further study showed that BnCHMP7 is highly expressed in leaves and that YFP-BnCHMP7 is predominantly localized in endosome. Compared with human CHMP7, we found that BnCHMP7 not only interacts with ESCRT-III subunits SNF7.2 (CHMP4B), but also with VPS2.2 and CHMP1B. As expected, microarray analysis revealed that the expression of ESCRT transport genes is significantly affected. Additionally, the expression of some genes that are involved in senescence, protein synthesis and protein degradation is also altered in BnCHMP7-overexpressing plants. Taken together, BnCHMP7 encodes an endosome-localized protein, which causes dwarfism and leaf senescence as an ESCRT-III-related component.
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Affiliation(s)
- Hongli Yang
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Wuhan 430062, PR China
| | - Jing Liu
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Wuhan 430062, PR China
| | - Jiulu Lin
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Wuhan 430062, PR China
| | - Linbin Deng
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Wuhan 430062, PR China
| | - Shihang Fan
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Wuhan 430062, PR China
| | - Yan Guo
- College of Life Sciences, Wuhan University, Wuhan 430072, PR China
| | - Fengming Sun
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Wuhan 430062, PR China
| | - Wei Hua
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Wuhan 430062, PR China.
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141
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Wang H, Zhuang X, Wang X, Law AHY, Zhao T, Du S, Loy MMT, Jiang L. A Distinct Pathway for Polar Exocytosis in Plant Cell Wall Formation. PLANT PHYSIOLOGY 2016; 172:1003-1018. [PMID: 27531442 PMCID: PMC5047090 DOI: 10.1104/pp.16.00754] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Accepted: 08/08/2016] [Indexed: 05/02/2023]
Abstract
Post-Golgi protein sorting and trafficking to the plasma membrane (PM) is generally believed to occur via the trans-Golgi network (TGN). In this study using Nicotiana tabacum pectin methylesterase (NtPPME1) as a marker, we have identified a TGN-independent polar exocytosis pathway that mediates cell wall formation during cell expansion and cytokinesis. Confocal immunofluorescence and immunogold electron microscopy studies demonstrated that Golgi-derived secretory vesicles (GDSVs) labeled by NtPPME1-GFP are distinct from those organelles belonging to the conventional post-Golgi exocytosis pathway. In addition, pharmaceutical treatments, superresolution imaging, and dynamic studies suggest that NtPPME1 follows a polar exocytic process from Golgi-GDSV-PM/cell plate (CP), which is distinct from the conventional Golgi-TGN-PM/CP secretion pathway. Further studies show that ROP1 regulates this specific polar exocytic pathway. Taken together, we have demonstrated an alternative TGN-independent Golgi-to-PM polar exocytic route, which mediates secretion of NtPPME1 for cell wall formation during cell expansion and cytokinesis and is ROP1-dependent.
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Affiliation(s)
- Hao Wang
- School of Life Sciences, Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China (H.W., X.Z., X.W., A.H.Y.L., L.J.);College of Life Sciences, South China Agricultural University, Guangzhou 510642, China (H.W.);Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China (T.Z., S.D., M.M.T.L.);Division of Biomedical Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China (S.D.); andCUHK Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen 518057, China (L.J.)
| | - Xiaohong Zhuang
- School of Life Sciences, Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China (H.W., X.Z., X.W., A.H.Y.L., L.J.);College of Life Sciences, South China Agricultural University, Guangzhou 510642, China (H.W.);Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China (T.Z., S.D., M.M.T.L.);Division of Biomedical Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China (S.D.); andCUHK Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen 518057, China (L.J.)
| | - Xiangfeng Wang
- School of Life Sciences, Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China (H.W., X.Z., X.W., A.H.Y.L., L.J.);College of Life Sciences, South China Agricultural University, Guangzhou 510642, China (H.W.);Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China (T.Z., S.D., M.M.T.L.);Division of Biomedical Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China (S.D.); andCUHK Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen 518057, China (L.J.)
| | - Angus Ho Yin Law
- School of Life Sciences, Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China (H.W., X.Z., X.W., A.H.Y.L., L.J.);College of Life Sciences, South China Agricultural University, Guangzhou 510642, China (H.W.);Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China (T.Z., S.D., M.M.T.L.);Division of Biomedical Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China (S.D.); andCUHK Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen 518057, China (L.J.)
| | - Teng Zhao
- School of Life Sciences, Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China (H.W., X.Z., X.W., A.H.Y.L., L.J.);College of Life Sciences, South China Agricultural University, Guangzhou 510642, China (H.W.);Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China (T.Z., S.D., M.M.T.L.);Division of Biomedical Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China (S.D.); andCUHK Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen 518057, China (L.J.)
| | - Shengwang Du
- School of Life Sciences, Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China (H.W., X.Z., X.W., A.H.Y.L., L.J.);College of Life Sciences, South China Agricultural University, Guangzhou 510642, China (H.W.);Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China (T.Z., S.D., M.M.T.L.);Division of Biomedical Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China (S.D.); andCUHK Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen 518057, China (L.J.)
| | - Michael M T Loy
- School of Life Sciences, Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China (H.W., X.Z., X.W., A.H.Y.L., L.J.);College of Life Sciences, South China Agricultural University, Guangzhou 510642, China (H.W.);Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China (T.Z., S.D., M.M.T.L.);Division of Biomedical Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China (S.D.); andCUHK Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen 518057, China (L.J.)
| | - Liwen Jiang
- School of Life Sciences, Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China (H.W., X.Z., X.W., A.H.Y.L., L.J.);College of Life Sciences, South China Agricultural University, Guangzhou 510642, China (H.W.);Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China (T.Z., S.D., M.M.T.L.);Division of Biomedical Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China (S.D.); andCUHK Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen 518057, China (L.J.)
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142
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Zhu X, Yin J, Liang S, Liang R, Zhou X, Chen Z, Zhao W, Wang J, Li W, He M, Yuan C, Miyamoto K, Ma B, Wang J, Qin P, Chen W, Wang Y, Wang W, Wu X, Yamane H, Zhu L, Li S, Chen X. The Multivesicular Bodies (MVBs)-Localized AAA ATPase LRD6-6 Inhibits Immunity and Cell Death Likely through Regulating MVBs-Mediated Vesicular Trafficking in Rice. PLoS Genet 2016; 12:e1006311. [PMID: 27618555 PMCID: PMC5019419 DOI: 10.1371/journal.pgen.1006311] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2015] [Accepted: 08/19/2016] [Indexed: 02/07/2023] Open
Abstract
Previous studies have shown that multivesicular bodies (MVBs)/endosomes-mediated vesicular trafficking may play key roles in plant immunity and cell death. However, the molecular regulation is poorly understood in rice. Here we report the identification and characterization of a MVBs-localized AAA ATPase LRD6-6 in rice. Disruption of LRD6-6 leads to enhanced immunity and cell death in rice. The ATPase activity and homo-dimerization of LRD6-6 is essential for its regulation on plant immunity and cell death. An ATPase inactive mutation (LRD6-6E315Q) leads to dominant-negative inhibition in plants. The LRD6-6 protein co-localizes with the MVBs marker protein RabF1/ARA6 and interacts with ESCRT-III components OsSNF7 and OsVPS2. Further analysis reveals that LRD6-6 is required for MVBs-mediated vesicular trafficking and inhibits the biosynthesis of antimicrobial compounds. Collectively, our study shows that the AAA ATPase LRD6-6 inhibits plant immunity and cell death most likely through modulating MVBs-mediated vesicular trafficking in rice. Plants have evolved sophistical immunity system in fighting against pathogenic micro-organisms including bacteria, fungi and oomycetes. Upon perception of pathogens, the immune system activates rapid cell death, characterized as a form of hypersensitive response typically in and around the infection sites to restrict pathogen invasion and prevent disease development. Recent studies have suggested that MVBs-mediated vesicular trafficking might play key roles in plant immunity and cell death. However, the molecular regulation is poorly known. By using the lesion resembling disease (lrd) mutant, lrd6-6, which exhibits autoimmunity and spontaneous cell death, we characterized LRD6-6 as a MVBs-localized AAA ATPase. We found that the ATPase LRD6-6 was required for MVBs-mediated vesicular trafficking and inhibited the biosynthesis of antimicrobial compounds for immune response in rice. Both the ATPase activity and homo-dimerization of LRD6-6 were essential for its inhibition on immunity and cell death. The catalytically inactive ATPase, LRD6-6E315Q, played dominant-negative effect on inhibition of immunity in plants. In addition, the LRD6-6 protein co-localized with the MVBs-spread marker protein RabF1/ARA6 and also interacted with ESCRT-III components OsSNF7 and OsVPS2. In summary, our study has shown that the AAA ATPase LRD6-6 inhibits plant immunity and cell death most likely through modulating MVBs-mediated vesicular trafficking in rice.
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Affiliation(s)
- Xiaobo Zhu
- State Key Laboratory of Hybrid Rice, Key Laboratory of Major Crop Diseases & Collaborative Innovation Center for Hybrid Rice in Yangtze River Basin, Rice Research Institute, Sichuan Agricultural University at Wenjiang, Chengdu, Sichuan, China
| | - Junjie Yin
- State Key Laboratory of Hybrid Rice, Key Laboratory of Major Crop Diseases & Collaborative Innovation Center for Hybrid Rice in Yangtze River Basin, Rice Research Institute, Sichuan Agricultural University at Wenjiang, Chengdu, Sichuan, China
| | - Sihui Liang
- State Key Laboratory of Hybrid Rice, Key Laboratory of Major Crop Diseases & Collaborative Innovation Center for Hybrid Rice in Yangtze River Basin, Rice Research Institute, Sichuan Agricultural University at Wenjiang, Chengdu, Sichuan, China
| | - Ruihong Liang
- State Key Laboratory of Hybrid Rice, Key Laboratory of Major Crop Diseases & Collaborative Innovation Center for Hybrid Rice in Yangtze River Basin, Rice Research Institute, Sichuan Agricultural University at Wenjiang, Chengdu, Sichuan, China
| | - Xiaogang Zhou
- State Key Laboratory of Hybrid Rice, Key Laboratory of Major Crop Diseases & Collaborative Innovation Center for Hybrid Rice in Yangtze River Basin, Rice Research Institute, Sichuan Agricultural University at Wenjiang, Chengdu, Sichuan, China
| | - Zhixiong Chen
- State Key Laboratory of Hybrid Rice, Key Laboratory of Major Crop Diseases & Collaborative Innovation Center for Hybrid Rice in Yangtze River Basin, Rice Research Institute, Sichuan Agricultural University at Wenjiang, Chengdu, Sichuan, China
| | - Wen Zhao
- State Key Laboratory of Hybrid Rice, Key Laboratory of Major Crop Diseases & Collaborative Innovation Center for Hybrid Rice in Yangtze River Basin, Rice Research Institute, Sichuan Agricultural University at Wenjiang, Chengdu, Sichuan, China
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Jing Wang
- State Key Laboratory of Hybrid Rice, Key Laboratory of Major Crop Diseases & Collaborative Innovation Center for Hybrid Rice in Yangtze River Basin, Rice Research Institute, Sichuan Agricultural University at Wenjiang, Chengdu, Sichuan, China
| | - Weitao Li
- State Key Laboratory of Hybrid Rice, Key Laboratory of Major Crop Diseases & Collaborative Innovation Center for Hybrid Rice in Yangtze River Basin, Rice Research Institute, Sichuan Agricultural University at Wenjiang, Chengdu, Sichuan, China
| | - Min He
- State Key Laboratory of Hybrid Rice, Key Laboratory of Major Crop Diseases & Collaborative Innovation Center for Hybrid Rice in Yangtze River Basin, Rice Research Institute, Sichuan Agricultural University at Wenjiang, Chengdu, Sichuan, China
| | - Can Yuan
- State Key Laboratory of Hybrid Rice, Key Laboratory of Major Crop Diseases & Collaborative Innovation Center for Hybrid Rice in Yangtze River Basin, Rice Research Institute, Sichuan Agricultural University at Wenjiang, Chengdu, Sichuan, China
| | - Koji Miyamoto
- Department of Biosciences, Faculty of Science and Engineering, Teikyo University, Utsunomiya, Tochigi, Japan
| | - Bingtian Ma
- State Key Laboratory of Hybrid Rice, Key Laboratory of Major Crop Diseases & Collaborative Innovation Center for Hybrid Rice in Yangtze River Basin, Rice Research Institute, Sichuan Agricultural University at Wenjiang, Chengdu, Sichuan, China
| | - Jichun Wang
- State Key Laboratory of Hybrid Rice, Key Laboratory of Major Crop Diseases & Collaborative Innovation Center for Hybrid Rice in Yangtze River Basin, Rice Research Institute, Sichuan Agricultural University at Wenjiang, Chengdu, Sichuan, China
| | - Peng Qin
- State Key Laboratory of Hybrid Rice, Key Laboratory of Major Crop Diseases & Collaborative Innovation Center for Hybrid Rice in Yangtze River Basin, Rice Research Institute, Sichuan Agricultural University at Wenjiang, Chengdu, Sichuan, China
| | - Weilan Chen
- State Key Laboratory of Hybrid Rice, Key Laboratory of Major Crop Diseases & Collaborative Innovation Center for Hybrid Rice in Yangtze River Basin, Rice Research Institute, Sichuan Agricultural University at Wenjiang, Chengdu, Sichuan, China
| | - Yuping Wang
- State Key Laboratory of Hybrid Rice, Key Laboratory of Major Crop Diseases & Collaborative Innovation Center for Hybrid Rice in Yangtze River Basin, Rice Research Institute, Sichuan Agricultural University at Wenjiang, Chengdu, Sichuan, China
| | - Wenming Wang
- State Key Laboratory of Hybrid Rice, Key Laboratory of Major Crop Diseases & Collaborative Innovation Center for Hybrid Rice in Yangtze River Basin, Rice Research Institute, Sichuan Agricultural University at Wenjiang, Chengdu, Sichuan, China
| | - Xianjun Wu
- State Key Laboratory of Hybrid Rice, Key Laboratory of Major Crop Diseases & Collaborative Innovation Center for Hybrid Rice in Yangtze River Basin, Rice Research Institute, Sichuan Agricultural University at Wenjiang, Chengdu, Sichuan, China
| | - Hisakazu Yamane
- Department of Biosciences, Faculty of Science and Engineering, Teikyo University, Utsunomiya, Tochigi, Japan
| | - Lihuang Zhu
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Shigui Li
- State Key Laboratory of Hybrid Rice, Key Laboratory of Major Crop Diseases & Collaborative Innovation Center for Hybrid Rice in Yangtze River Basin, Rice Research Institute, Sichuan Agricultural University at Wenjiang, Chengdu, Sichuan, China
| | - Xuewei Chen
- State Key Laboratory of Hybrid Rice, Key Laboratory of Major Crop Diseases & Collaborative Innovation Center for Hybrid Rice in Yangtze River Basin, Rice Research Institute, Sichuan Agricultural University at Wenjiang, Chengdu, Sichuan, China
- * E-mail:
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143
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Klinger CM, Ramirez-Macias I, Herman EK, Turkewitz AP, Field MC, Dacks JB. Resolving the homology-function relationship through comparative genomics of membrane-trafficking machinery and parasite cell biology. Mol Biochem Parasitol 2016; 209:88-103. [PMID: 27444378 PMCID: PMC5140719 DOI: 10.1016/j.molbiopara.2016.07.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Revised: 07/12/2016] [Accepted: 07/16/2016] [Indexed: 10/21/2022]
Abstract
With advances in DNA sequencing technology, it is increasingly common and tractable to informatically look for genes of interest in the genomic databases of parasitic organisms and infer cellular states. Assignment of a putative gene function based on homology to functionally characterized genes in other organisms, though powerful, relies on the implicit assumption of functional homology, i.e. that orthology indicates conserved function. Eukaryotes reveal a dazzling array of cellular features and structural organization, suggesting a concomitant diversity in their underlying molecular machinery. Significantly, examples of novel functions for pre-existing or new paralogues are not uncommon. Do these examples undermine the basic assumption of functional homology, especially in parasitic protists, which are often highly derived? Here we examine the extent to which functional homology exists between organisms spanning the eukaryotic lineage. By comparing membrane trafficking proteins between parasitic protists and traditional model organisms, where direct functional evidence is available, we find that function is indeed largely conserved between orthologues, albeit with significant adaptation arising from the unique biological features within each lineage.
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Affiliation(s)
- Christen M Klinger
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
| | | | - Emily K Herman
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
| | - Aaron P Turkewitz
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL, USA
| | - Mark C Field
- School of Life Sciences, University of Dundee, Dundee, UK
| | - Joel B Dacks
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada.
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144
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Wang J, Ding Y, Zhuang X, Hu S, Jiang L. Protein Co-localization Studies: Issues and Considerations. MOLECULAR PLANT 2016; 9:1221-1223. [PMID: 27235545 DOI: 10.1016/j.molp.2016.05.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Revised: 05/04/2016] [Accepted: 05/17/2016] [Indexed: 06/05/2023]
Affiliation(s)
- Juan Wang
- State Key Laboratory of Agrobiotechnology, Centre for Cell and Developmental Biology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Yu Ding
- State Key Laboratory of Agrobiotechnology, Centre for Cell and Developmental Biology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Xiaohong Zhuang
- State Key Laboratory of Agrobiotechnology, Centre for Cell and Developmental Biology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Shuai Hu
- State Key Laboratory of Agrobiotechnology, Centre for Cell and Developmental Biology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Liwen Jiang
- State Key Laboratory of Agrobiotechnology, Centre for Cell and Developmental Biology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China; CUHK Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen 518057, China.
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145
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Cui Y, Shen J, Gao C, Zhuang X, Wang J, Jiang L. Biogenesis of Plant Prevacuolar Multivesicular Bodies. MOLECULAR PLANT 2016; 9:774-86. [PMID: 26836198 DOI: 10.1016/j.molp.2016.01.011] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 01/04/2016] [Accepted: 01/26/2016] [Indexed: 05/20/2023]
Abstract
Plant prevacuolar compartments (PVCs), or multivesicular bodies (MVBs), are single membrane-bound organelles that play important roles in mediating protein trafficking to vacuoles in the secretory pathway. PVC/MVB also serves as a late endosome in the endocytic pathway in plants. Since the plant PVC was identified as an MVB more than 10 years ago, great progress has been made toward the understanding of PVC/MVB function and biogenesis in plants. In this review, we first summarize previous research into the identification and characterization of plant PVCs/MVBs, and then highlight recent advances on the mechanisms underlying intraluminal vesicle formation and maturation of plant PVCs/MVBs. In addition, we discuss the possible crosstalk that appears to occur between PVCs/MVBs and autophagosomes during autophagy in plants. Finally, we list some open questions and present future perspectives in this field.
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Affiliation(s)
- Yong Cui
- State Key Laboratory of Agrobiotechnology, Centre for Cell & Developmental Biology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Jinbo Shen
- State Key Laboratory of Agrobiotechnology, Centre for Cell & Developmental Biology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Caiji Gao
- State Key Laboratory of Agrobiotechnology, Centre for Cell & Developmental Biology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Xiaohong Zhuang
- State Key Laboratory of Agrobiotechnology, Centre for Cell & Developmental Biology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Junqi Wang
- State Key Laboratory of Agrobiotechnology, Centre for Cell & Developmental Biology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China; Shenzhen Key Laboratory of Cell Microenvironment, Department of Biology, South University of Science and Technology of China, Shenzhen 518055, China
| | - Liwen Jiang
- State Key Laboratory of Agrobiotechnology, Centre for Cell & Developmental Biology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China; CUHK Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen 518057, China.
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146
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Shen J, Gao C, Zhao Q, Lin Y, Wang X, Zhuang X, Jiang L. AtBRO1 Functions in ESCRT-I Complex to Regulate Multivesicular Body Protein Sorting. MOLECULAR PLANT 2016; 9:760-763. [PMID: 26902184 DOI: 10.1016/j.molp.2016.02.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 01/27/2016] [Accepted: 02/15/2016] [Indexed: 05/20/2023]
Affiliation(s)
- Jinbo Shen
- State Key Laboratory of Agrobiotechnology, Centre for Cell and Developmental Biology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Caiji Gao
- State Key Laboratory of Agrobiotechnology, Centre for Cell and Developmental Biology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Qiong Zhao
- State Key Laboratory of Agrobiotechnology, Centre for Cell and Developmental Biology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Youshun Lin
- State Key Laboratory of Agrobiotechnology, Centre for Cell and Developmental Biology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Xiangfeng Wang
- State Key Laboratory of Agrobiotechnology, Centre for Cell and Developmental Biology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Xiaohong Zhuang
- State Key Laboratory of Agrobiotechnology, Centre for Cell and Developmental Biology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Liwen Jiang
- State Key Laboratory of Agrobiotechnology, Centre for Cell and Developmental Biology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China; CUHK Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen 518057, China.
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147
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Wan S, Jiang L. Endoplasmic reticulum (ER) stress and the unfolded protein response (UPR) in plants. PROTOPLASMA 2016; 253:753-764. [PMID: 26060134 DOI: 10.1007/s00709-015-0842-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 05/30/2015] [Indexed: 05/03/2023]
Abstract
Being a major factory for protein synthesis, assembly, and export, the endoplasmic reticulum (ER) has a precise and robust ER quality control (ERQC) system monitoring its product line. However, when organisms are subjected to environmental stress, whether biotic or abiotic, the levels of misfolded proteins may overwhelm the ERQC system, tilting the balance between the capacity of and demand for ER quality control and resulting in a scenario termed ER stress. Intense or prolonged ER stress may cause damage to the ER as well as to other organelles, or even lead to cell death in extreme cases. To avoid such serious consequences, cells activate self-rescue programs to restore protein homeostasis in the ER, either through the enhancement of protein-folding and degradation competence or by alleviating the demands for such reactions. These are collectively called the unfolded protein response (UPR). Long investigated in mammalian cells and yeasts, the UPR is also of great interest to plant scientists. Among the three branches of UPR discovered in mammals, two have been studied in plants with plant homologs existing of the ER-membrane-associated activating transcription factor 6 (ATF6) and inositol-requiring enzyme 1 (IRE1). This review discusses the molecular mechanisms of these two types of UPR in plants, as well as the consequences of insufficient UPR, with a focus on experiments using model plants.
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Affiliation(s)
- Shucen Wan
- Molecular Biotechnology Program, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
| | - Liwen Jiang
- Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
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148
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Paez Valencia J, Goodman K, Otegui MS. Endocytosis and Endosomal Trafficking in Plants. ANNUAL REVIEW OF PLANT BIOLOGY 2016; 67:309-35. [PMID: 27128466 DOI: 10.1146/annurev-arplant-043015-112242] [Citation(s) in RCA: 153] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Endocytosis and endosomal trafficking are essential processes in cells that control the dynamics and turnover of plasma membrane proteins, such as receptors, transporters, and cell wall biosynthetic enzymes. Plasma membrane proteins (cargo) are internalized by endocytosis through clathrin-dependent or clathrin-independent mechanism and delivered to early endosomes. From the endosomes, cargo proteins are recycled back to the plasma membrane via different pathways, which rely on small GTPases and the retromer complex. Proteins that are targeted for degradation through ubiquitination are sorted into endosomal vesicles by the ESCRT (endosomal sorting complex required for transport) machinery for degradation in the vacuole. Endocytic and endosomal trafficking regulates many cellular, developmental, and physiological processes, including cellular polarization, hormone transport, metal ion homeostasis, cytokinesis, pathogen responses, and development. In this review, we discuss the mechanisms that mediate the recognition and sorting of endocytic and endosomal cargos, the vesiculation processes that mediate their trafficking, and their connection to cellular and physiological responses in plants.
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Affiliation(s)
- Julio Paez Valencia
- Department of Botany
- R.M. Bock Laboratories of Cell and Molecular Biology, and
| | - Kaija Goodman
- Department of Botany
- R.M. Bock Laboratories of Cell and Molecular Biology, and
| | - Marisa S Otegui
- Department of Botany
- R.M. Bock Laboratories of Cell and Molecular Biology, and
- Department of Genetics, University of Wisconsin-Madison, Madison, Wisconsin 53706; , ,
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149
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Cui Y, Gao C, Zhao Q, Jiang L. Using Fluorescent Protein Fusions to Study Protein Subcellular Localization and Dynamics in Plant Cells. Methods Mol Biol 2016; 1474:113-23. [PMID: 27515077 DOI: 10.1007/978-1-4939-6352-2_7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Studies of protein subcellular localization and dynamics are helpful in understanding the cellular functions of proteins in an organism. In the past decade, the use of green fluorescent protein (GFP) as a fusion tag has dramatically extended our knowledge in this field. Transient expression and stable transformation of GFP-tagged proteins have been wildly used to study protein localization in vivo in different systems. Although GFP-based tags provide a fast and convenient way to characterize protein properties in living cells, several reports have demonstrated that GFP fusions might not accurately reflect the localization of the native protein as GFP tags may alter the protein properties. To facilitate proper usage of GFP tags in plant cell biology study, we describe detailed protocols to identify possible inhibitory effects of fluorescent tags on protein subcellular localization and to determine if a fluorescently tagged protein is localized to the correct subcellular compartment. Using Arabidopsis Endomembrane protein 12 (EMP12) as an example, we first show the possible inhibitory effect of GFP tags on proper protein localization and then describe the immunofluorescence labeling method to verify the correct localization of GFP fusion proteins. Next, a method is presented using the ImageJ program with the Pearson-Spearman correlation (PSC) colocalization plug-in for statistical quantification of colocalization ratios of two fluorophores. Finally we provide a detailed method for protein dynamics studies using spinning disk confocal microscopy in Arabidopsis cells.
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Affiliation(s)
- Yong Cui
- Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
| | - Caiji Gao
- Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Qiong Zhao
- Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Liwen Jiang
- Centre for Cell and Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
- CUHK Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, 518057, China.
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150
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Robinson DG, Ding Y, Jiang L. Unconventional protein secretion in plants: a critical assessment. PROTOPLASMA 2016; 253:31-43. [PMID: 26410830 DOI: 10.1007/s00709-015-0887-1] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 09/18/2015] [Indexed: 05/27/2023]
Abstract
Unconventional protein secretion (UPS) is a collective term for mechanisms by which cytosolic proteins that lack a signal peptide ("leaderless secretory proteins" (LSPs)) can gain access to the cell exterior. Numerous examples of UPS have been well documented in animal and yeast cells. In contrast, our understanding of the mechanism(s) and function of UPS in plants is very limited. This review evaluates the available literature on this subject. The apparent large numbers of LSPs in the plant secretome suggest that UPS also occurs in plants but is not a proof. Although the direct transport of LSPs across the plant plasma membrane (PM) has not yet been described, it is possible that as in other eukaryotes, exosomes may be released from plant cells through fusion of multivesicular bodies (MVBs) with the PM. In this way, LSPs, but also small RNAs (sRNAs), that are passively taken up from the cytosol into the intraluminal vesicles of MVBs, could reach the apoplast. Another possible mechanism is the recently discovered exocyst-positive organelle (EXPO), a double-membrane-bound compartment, distinct from autophagosomes, which appears to sequester LSPs.
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Affiliation(s)
- David G Robinson
- Centre for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 230, D-69120, Heidelberg, Germany.
| | - Yu Ding
- Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Liwen Jiang
- Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
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