1
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Li J, Zhang M, Zhou L. Protein S-acyltransferases and acyl protein thioesterases, regulation executors of protein S-acylation in plants. FRONTIERS IN PLANT SCIENCE 2022; 13:956231. [PMID: 35968095 PMCID: PMC9363829 DOI: 10.3389/fpls.2022.956231] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 07/05/2022] [Indexed: 06/15/2023]
Abstract
Protein S-acylation, also known as palmitoylation, is an important lipid post-translational modification of proteins in eukaryotes. S-acylation plays critical roles in a variety of protein functions involved in plant development and responses to abiotic and biotic stresses. The status of S-acylation on proteins is dynamic and reversible, which is catalyzed by protein S-acyltransferases (PATs) and reversed by acyl protein thioesterases. The cycle of S-acylation and de-S-acylation provides a molecular mechanism for membrane-associated proteins to undergo cycling and trafficking between different cell compartments and thus works as a switch to initiate or terminate particular signaling transductions on the membrane surface. In plants, thousands of proteins have been identified to be S-acylated through proteomics. Many S-acylated proteins and quite a few PAT-substrate pairs have been functionally characterized. A recently characterized acyl protein thioesterases family, ABAPT family proteins in Arabidopsis, has provided new insights into the de-S-acylation process. However, our understanding of the regulatory mechanisms controlling the S-acylation and de-S-acylation process is surprisingly incomplete. In this review, we discuss how protein S-acylation level is regulated with the focus on catalyzing enzymes in plants. We also propose the challenges and potential developments for the understanding of the regulatory mechanisms controlling protein S-acylation in plants.
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Affiliation(s)
- Jincheng Li
- College of Forestry, Co-Innovation Center for the Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, China
| | - Manqi Zhang
- College of Forestry, Co-Innovation Center for the Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, China
| | - Lijuan Zhou
- College of Forestry, Co-Innovation Center for the Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, China
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2
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Kumar M, Carr P, Turner SR. An atlas of Arabidopsis protein S-acylation reveals its widespread role in plant cell organization and function. NATURE PLANTS 2022. [PMID: 35681017 DOI: 10.1101/2020.05.12.090415] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
S-acylation is the addition of a fatty acid to a cysteine residue of a protein. While this modification may profoundly alter protein behaviour, its effects on the function of plant proteins remains poorly characterized, largely as a result of the lack of basic information regarding which proteins are S-acylated and where in the proteins the modification occurs. To address this gap in our knowledge, we used an optimized acyl-resin-assisted capture assay to perform a comprehensive analysis of plant protein S-acylation from six separate tissues. In our high- and medium-confidence groups, we identified 1,849 cysteines modified by S-acylation, which were located in 1,640 unique peptides from 1,094 different proteins. This represents around 6% of the detectable Arabidopsis proteome and suggests an important role for S-acylation in many essential cellular functions including trafficking, signalling and metabolism. To illustrate the potential of this dataset, we focus on cellulose synthesis and confirm the S-acylation of a number of proteins known to be involved in cellulose synthesis and trafficking of the cellulose synthase complex. In the secondary cell walls, cellulose synthesis requires three different catalytic subunits (CESA4, CESA7 and CESA8) that all exhibit striking sequence similarity and are all predicted to possess a RING-type zinc finger at their amino terminus composed of eight cysteines. For CESA8, we find evidence for S-acylation of these cysteines that is incompatible with any role in coordinating metal ions. We show that while CESA7 may possess a RING-type domain, the same region of CESA8 appears to have evolved a very different structure. Together, the data suggest that this study represents an atlas of S-acylation in Arabidopsis that will facilitate the broader study of this elusive post-translational modification in plants as well as demonstrating the importance of further work in this area.
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Affiliation(s)
- Manoj Kumar
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Paul Carr
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
- Holiferm, Manchester, UK
| | - Simon R Turner
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.
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3
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Kumar M, Carr P, Turner SR. An atlas of Arabidopsis protein S-acylation reveals its widespread role in plant cell organization and function. NATURE PLANTS 2022; 8:670-681. [PMID: 35681017 DOI: 10.1038/s41477-022-01164-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 05/04/2022] [Indexed: 05/28/2023]
Abstract
S-acylation is the addition of a fatty acid to a cysteine residue of a protein. While this modification may profoundly alter protein behaviour, its effects on the function of plant proteins remains poorly characterized, largely as a result of the lack of basic information regarding which proteins are S-acylated and where in the proteins the modification occurs. To address this gap in our knowledge, we used an optimized acyl-resin-assisted capture assay to perform a comprehensive analysis of plant protein S-acylation from six separate tissues. In our high- and medium-confidence groups, we identified 1,849 cysteines modified by S-acylation, which were located in 1,640 unique peptides from 1,094 different proteins. This represents around 6% of the detectable Arabidopsis proteome and suggests an important role for S-acylation in many essential cellular functions including trafficking, signalling and metabolism. To illustrate the potential of this dataset, we focus on cellulose synthesis and confirm the S-acylation of a number of proteins known to be involved in cellulose synthesis and trafficking of the cellulose synthase complex. In the secondary cell walls, cellulose synthesis requires three different catalytic subunits (CESA4, CESA7 and CESA8) that all exhibit striking sequence similarity and are all predicted to possess a RING-type zinc finger at their amino terminus composed of eight cysteines. For CESA8, we find evidence for S-acylation of these cysteines that is incompatible with any role in coordinating metal ions. We show that while CESA7 may possess a RING-type domain, the same region of CESA8 appears to have evolved a very different structure. Together, the data suggest that this study represents an atlas of S-acylation in Arabidopsis that will facilitate the broader study of this elusive post-translational modification in plants as well as demonstrating the importance of further work in this area.
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Affiliation(s)
- Manoj Kumar
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Paul Carr
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
- Holiferm, Manchester, UK
| | - Simon R Turner
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.
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4
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Tian Y, Zeng H, Wu J, Huang J, Gao Q, Tang D, Cai L, Liao Z, Wang Y, Liu X, Lin J. Screening DHHCs of S-acylated proteins using an OsDHHC cDNA library and bimolecular fluorescence complementation in rice. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 110:1763-1780. [PMID: 35411551 DOI: 10.1111/tpj.15769] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 03/30/2022] [Accepted: 04/07/2022] [Indexed: 05/28/2023]
Abstract
S-acylation is an important lipid modification that primarily involves DHHC proteins (DHHCs) and associated S-acylated proteins. No DHHC-S-acylated protein pair has been reported so far in rice (Oryza sativa L.) and the molecular mechanisms underlying S-acylation in plants are largely unknown. We constructed an OsDHHC cDNA library for screening corresponding pairs of DHHCs and S-acylated proteins using bimolecular fluorescence complementation assays. Five DHHC-S-acylated protein pairs (OsDHHC30-OsCBL2, OsDHHC30-OsCBL3, OsDHHC18-OsNOA1, OsDHHC13-OsNAC9, and OsDHHC14-GSD1) were identified in rice. Among the pairs, OsCBL2 and OsCBL3 were S-acylated by OsDHHC30 in yeast and rice. The localization of OsCBL2 and OsCBL3 in the endomembrane depended on S-acylation mediated by OsDHHC30. Meanwhile, all four OsDHHCs screened complemented the thermosensitive phenotype of an akr1 yeast mutant, and their DHHC motifs were required for S-acyltransferase activity. Overexpression of OsDHHC30 in rice plants improved their salt and oxidative tolerance. Together, these results contribute to our understanding of the molecular mechanism underlying S-acylation in plants.
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Affiliation(s)
- Ye Tian
- Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, State Key Laboratory of Chemo/Biosensing and Chemometrics, National Center of Technology Innovation for Saline-Alkali Tolerant Rice, College of Biology, Hunan University, Changsha, 410082, Hunan, China
| | - Hui Zeng
- Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, State Key Laboratory of Chemo/Biosensing and Chemometrics, National Center of Technology Innovation for Saline-Alkali Tolerant Rice, College of Biology, Hunan University, Changsha, 410082, Hunan, China
| | - Jicai Wu
- Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, State Key Laboratory of Chemo/Biosensing and Chemometrics, National Center of Technology Innovation for Saline-Alkali Tolerant Rice, College of Biology, Hunan University, Changsha, 410082, Hunan, China
| | - Jian Huang
- Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, State Key Laboratory of Chemo/Biosensing and Chemometrics, National Center of Technology Innovation for Saline-Alkali Tolerant Rice, College of Biology, Hunan University, Changsha, 410082, Hunan, China
| | - Qiang Gao
- Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, State Key Laboratory of Chemo/Biosensing and Chemometrics, National Center of Technology Innovation for Saline-Alkali Tolerant Rice, College of Biology, Hunan University, Changsha, 410082, Hunan, China
| | - Dongying Tang
- Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, State Key Laboratory of Chemo/Biosensing and Chemometrics, National Center of Technology Innovation for Saline-Alkali Tolerant Rice, College of Biology, Hunan University, Changsha, 410082, Hunan, China
| | - Lipeng Cai
- Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, State Key Laboratory of Chemo/Biosensing and Chemometrics, National Center of Technology Innovation for Saline-Alkali Tolerant Rice, College of Biology, Hunan University, Changsha, 410082, Hunan, China
| | - Zhaoyi Liao
- Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, State Key Laboratory of Chemo/Biosensing and Chemometrics, National Center of Technology Innovation for Saline-Alkali Tolerant Rice, College of Biology, Hunan University, Changsha, 410082, Hunan, China
| | - Yan Wang
- Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, State Key Laboratory of Chemo/Biosensing and Chemometrics, National Center of Technology Innovation for Saline-Alkali Tolerant Rice, College of Biology, Hunan University, Changsha, 410082, Hunan, China
| | - Xuanming Liu
- Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, State Key Laboratory of Chemo/Biosensing and Chemometrics, National Center of Technology Innovation for Saline-Alkali Tolerant Rice, College of Biology, Hunan University, Changsha, 410082, Hunan, China
| | - Jianzhong Lin
- Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, State Key Laboratory of Chemo/Biosensing and Chemometrics, National Center of Technology Innovation for Saline-Alkali Tolerant Rice, College of Biology, Hunan University, Changsha, 410082, Hunan, China
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5
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Cho SH, Tóth K, Kim D, Vo PH, Lin CH, Handakumbura PP, Ubach AR, Evans S, Paša-Tolić L, Stacey G. Activation of the plant mevalonate pathway by extracellular ATP. Nat Commun 2022; 13:450. [PMID: 35064110 PMCID: PMC8783019 DOI: 10.1038/s41467-022-28150-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 01/10/2022] [Indexed: 12/28/2022] Open
Abstract
The mevalonate pathway plays a critical role in multiple cellular processes in both animals and plants. In plants, the products of this pathway impact growth and development, as well as the response to environmental stress. A forward genetic screen of Arabidopsis thaliana using Ca2+-imaging identified mevalonate kinase (MVK) as a critical component of plant purinergic signaling. MVK interacts directly with the plant extracellular ATP (eATP) receptor P2K1 and is phosphorylated by P2K1 in response to eATP. Mutation of P2K1-mediated phosphorylation sites in MVK eliminates the ATP-induced cytoplasmic calcium response, MVK enzymatic activity, and suppresses pathogen defense. The data demonstrate that the plasma membrane associated P2K1 directly impacts plant cellular metabolism by phosphorylation of MVK, a key enzyme in the mevalonate pathway. The results underline the importance of purinergic signaling in plants and the ability of eATP to influence the activity of a key metabolite pathway with global effects on plant metabolism. Products of the mevalonate pathway support plant development. Here the authors show that the extracellular ATP receptor P2K1 phosphorylates mevalonate kinase and this affects the mevalonate pathway.
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6
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Yang B, Zhang K, Jin X, Yan J, Lu S, Shen Q, Guo L, Hong Y, Wang X, Guo L. Acylation of non-specific phospholipase C4 determines its function in plant response to phosphate deficiency. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 106:1647-1659. [PMID: 33792991 DOI: 10.1111/tpj.15260] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Revised: 03/19/2021] [Accepted: 03/26/2021] [Indexed: 06/12/2023]
Abstract
Non-specific phospholipase C (NPC) is involved in plant growth, development and stress responses. To elucidate the mechanism by which NPCs mediate cellular functions, here we show that NPC4 is S-acylated at the C terminus and that acylation determines its plasma membrane (PM) association and function. The acylation of NPC4 was detected using NPC4 isolated from Arabidopsis and reconstituted in vitro. The C-terminal Cys-533 was identified as the S-acylation residue, and the mutation of Cys-533 to Ala-533 in NPC4 (NPC4C533A ) led to the loss of S-acylation and membrane association of NPC4. The knockout of NPC4 impeded the phosphate deficiency-induced decrease of the phosphosphingolipid glycosyl inositol phosphoryl ceramide (GIPC), but introducing NPC4C533A to npc4-1 failed to complement this defect, thereby supporting the hypothesis that the non-acylated NPC4C533A fails to hydrolyze GIPC during phosphate deprivation. Moreover, NPC4C533A failed to complement the primary root growth in npc4-1 under stress. In addition, NPC4 in Brassica napus was S-acylated and mutation of the S-acylating cysteine residue of BnaC01.NPC4 led to the loss of S-acylation and its membrane association. Together, our results reveal that S-acylation of NPC4 in the C terminus is conserved and required for its membrane association, phosphosphingolipid hydrolysis and function in plant stress responses.
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Affiliation(s)
- Bao Yang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070, China
| | - Ke Zhang
- Department of Biology, University of Missouri, St. Louis, MO, 63121, USA
- Donald Danforth Plant Science Center, St. Louis, MO, 63132, USA
| | - Xiong Jin
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070, China
| | - Jiayu Yan
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070, China
| | - Shaoping Lu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070, China
| | - Qingwen Shen
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070, China
| | - Lei Guo
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070, China
| | - Yueyun Hong
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070, China
| | - Xuemin Wang
- Department of Biology, University of Missouri, St. Louis, MO, 63121, USA
- Donald Danforth Plant Science Center, St. Louis, MO, 63132, USA
| | - Liang Guo
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070, China
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7
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Jiang H, Ma QJ, Zhong MS, Gao HN, Li YY, Hao YJ. The apple palmitoyltransferase MdPAT16 influences sugar content and salt tolerance via an MdCBL1-MdCIPK13-MdSUT2.2 pathway. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 106:689-705. [PMID: 33548154 DOI: 10.1111/tpj.15191] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 01/22/2021] [Accepted: 02/02/2021] [Indexed: 05/21/2023]
Abstract
Protein S-acyltransferases (PATs) are a category of eukaryotic transmembrane proteins that mediate the S-acylation of their target proteins. S-acylation, commonly known as palmitoylation, is a reversible protein modification that regulates the membrane association and function of target proteins. However, the functions and mechanisms of PATs in apple (Malus domestica) remain poorly understood. In this study, an MdPAT family member, MdPAT16, was identified and shown to have palmitoyltransferase activity. We demonstrated that this gene responds to salt stress and that its expression improves plant salt stress resistance. In addition, its overexpression significantly promotes the accumulation of soluble sugars. The same phenotypes were observed in transgenic tissue culture seedlings, transgenic roots, and Arabidopsis thaliana that ectopically expressed MdPAT16. MdPAT16 was shown to interact with MdCBL1 and stabilize MdCBL1 protein levels through palmitoylation. The N-terminal sequence of MdCBL1 contains a palmitoylation site, and its N-terminal deletion led to changes in MdCBL1 protein stability and subcellular localization. The phenotypes of MdCBL1 transgenic roots and transiently injected apple fruits were fully consistent with the sugar accumulation phenotype of MdPAT16. Mutation of the palmitoylation site interfered with this phenotype. These findings suggest that MdPAT16 palmitoylates its downstream target proteins, improving their stability. This may be a missing link in the plant salt stress response pathway and have an important impact on fruit quality.
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Affiliation(s)
- Han Jiang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Qi-Jun Ma
- State Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, Shandong Collaborative Innovation Center of Fruit & Vegetable Quality and Efficient Production, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai'an, Shandong, 271018, China
| | - Ming-Shuang Zhong
- State Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, Shandong Collaborative Innovation Center of Fruit & Vegetable Quality and Efficient Production, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai'an, Shandong, 271018, China
| | - Huai-Na Gao
- State Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, Shandong Collaborative Innovation Center of Fruit & Vegetable Quality and Efficient Production, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai'an, Shandong, 271018, China
| | - Yuan-Yuan Li
- State Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, Shandong Collaborative Innovation Center of Fruit & Vegetable Quality and Efficient Production, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai'an, Shandong, 271018, China
| | - Yu-Jin Hao
- State Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, Shandong Collaborative Innovation Center of Fruit & Vegetable Quality and Efficient Production, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai'an, Shandong, 271018, China
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8
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McFarlane HE, Mutwil-Anderwald D, Verbančič J, Picard KL, Gookin TE, Froehlich A, Chakravorty D, Trindade LM, Alonso JM, Assmann SM, Persson S. A G protein-coupled receptor-like module regulates cellulose synthase secretion from the endomembrane system in Arabidopsis. Dev Cell 2021; 56:1484-1497.e7. [PMID: 33878345 DOI: 10.1016/j.devcel.2021.03.031] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 12/16/2020] [Accepted: 03/29/2021] [Indexed: 01/18/2023]
Abstract
Cellulose is produced at the plasma membrane of plant cells by cellulose synthase (CESA) complexes (CSCs). CSCs are assembled in the endomembrane system and then trafficked to the plasma membrane. Because CESAs are only active in the plasma membrane, control of CSC secretion regulates cellulose synthesis. We identified members of a family of seven transmembrane domain-containing proteins (7TMs) that are important for cellulose production during cell wall integrity stress. 7TMs are often associated with guanine nucleotide-binding (G) protein signaling and we found that mutants affecting the Gβγ dimer phenocopied the 7tm mutants. Unexpectedly, the 7TMs localized to the Golgi/trans-Golgi network where they interacted with G protein components. Here, the 7TMs and Gβγ regulated CESA trafficking but did not affect general protein secretion. Our results outline how a G protein-coupled module regulates CESA trafficking and reveal that defects in this process lead to exacerbated responses to cell wall integrity stress.
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Affiliation(s)
- Heather E McFarlane
- School of Biosciences, University of Melbourne, Parkville 3010 VIC, Australia; Max-Planck Institute for Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam, Germany; Department of Cell and Systems Biology, University of Toronto, 25 Harbord St, Toronto, ON M5S 3G5, Canada.
| | - Daniela Mutwil-Anderwald
- Max-Planck Institute for Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam, Germany; School of the Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore
| | - Jana Verbančič
- School of Biosciences, University of Melbourne, Parkville 3010 VIC, Australia; Max-Planck Institute for Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam, Germany
| | - Kelsey L Picard
- School of Biosciences, University of Melbourne, Parkville 3010 VIC, Australia; School of Natural Sciences, University of Tasmania, Hobart 7001 TAS, Australia
| | - Timothy E Gookin
- Department of Biology, The Pennsylvania State University, Mueller Laboratory, University Park, PA 16802, USA
| | - Anja Froehlich
- Max-Planck Institute for Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam, Germany
| | - David Chakravorty
- Department of Biology, The Pennsylvania State University, Mueller Laboratory, University Park, PA 16802, USA
| | - Luisa M Trindade
- Plant Breeding, Wageningen University and Research, Droevendaalsesteeg 1, 6708 PB Wageningen, the Netherlands
| | - Jose M Alonso
- Department of Plant and Microbial Biology, Program in Genetics, North Carolina State University, Raleigh, NC 27695-7614, USA
| | - Sarah M Assmann
- Department of Biology, The Pennsylvania State University, Mueller Laboratory, University Park, PA 16802, USA
| | - Staffan Persson
- School of Biosciences, University of Melbourne, Parkville 3010 VIC, Australia; Max-Planck Institute for Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam, Germany; Department of Plant & Environmental Sciences, University of Copenhagen, 1871 Frederiksberg C, Denmark; Copenhagen Plant Science Center, University of Copenhagen, 1871 Frederiksberg C, Denmark; Joint International Research Laboratory of Metabolic & Developmental Sciences, State Key Laboratory of Hybrid Rice, SJTU-University of Adelaide Joint Centre for Agriculture and Health, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China.
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9
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Jeon BW, Acharya BR, Assmann SM. The Arabidopsis heterotrimeric G-protein β subunit, AGB1, is required for guard cell calcium sensing and calcium-induced calcium release. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2019; 99:231-244. [PMID: 30882980 DOI: 10.1111/tpj.14318] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 03/04/2019] [Accepted: 03/13/2019] [Indexed: 05/08/2023]
Abstract
Cytosolic calcium concentration ([Ca2+ ]cyt ) and heterotrimeric G-proteins are universal eukaryotic signaling elements. In plant guard cells, extracellular calcium (Cao ) is as strong a stimulus for stomatal closure as the phytohormone abscisic acid (ABA), but underlying mechanisms remain elusive. Here, we report that the sole Arabidopsis heterotrimeric Gβ subunit, AGB1, is required for four guard cell Cao responses: induction of stomatal closure; inhibition of stomatal opening; [Ca2+ ]cyt oscillation; and inositol 1,4,5-trisphosphate (InsP3) production. Stomata in wild-type Arabidopsis (Col) and in mutants of the canonical Gα subunit, GPA1, showed inhibition of stomatal opening and promotion of stomatal closure by Cao . By contrast, stomatal movements of agb1 mutants and agb1/gpa1 double-mutants, as well as those of the agg1agg2 Gγ double-mutant, were insensitive to Cao . These behaviors contrast with ABA-regulated stomatal movements, which involve GPA1 and AGB1/AGG3 dimers, illustrating differential partitioning of G-protein subunits among stimuli with similar ultimate impacts, which may facilitate stimulus-specific encoding. AGB1 knockouts retained reactive oxygen species and NO production, but lost YC3.6-detected [Ca2+ ]cyt oscillations in response to Cao , initiating only a single [Ca2+ ]cyt spike. Experimentally imposed [Ca2+ ]cyt oscillations restored stomatal closure in agb1. Yeast two-hybrid and bimolecular complementation fluorescence experiments revealed that AGB1 interacts with phospholipase Cs (PLCs), and Cao induced InsP3 production in Col but not in agb1. In sum, G-protein signaling via AGB1/AGG1/AGG2 is essential for Cao -regulation of stomatal apertures, and stomatal movements in response to Cao apparently require Ca2+ -induced Ca2+ release that is likely dependent on Gβγ interaction with PLCs leading to InsP3 production.
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Affiliation(s)
- Byeong Wook Jeon
- Department of Biology, Pennsylvania State University, University Park, PA, 16802, USA
- Department of Bioenergy Science and Technology, Chonnam National University, Gwangju, 61186, Korea
| | - Biswa R Acharya
- Department of Biology, Pennsylvania State University, University Park, PA, 16802, USA
| | - Sarah M Assmann
- Department of Biology, Pennsylvania State University, University Park, PA, 16802, USA
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10
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Pandey S. Heterotrimeric G-Protein Signaling in Plants: Conserved and Novel Mechanisms. ANNUAL REVIEW OF PLANT BIOLOGY 2019; 70:213-238. [PMID: 31035831 DOI: 10.1146/annurev-arplant-050718-100231] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Heterotrimeric GTP-binding proteins are key regulators of a multitude of signaling pathways in all eukaryotes. Although the core G-protein components and their basic biochemistries are broadly conserved throughout evolution, the regulatory mechanisms of G proteins seem to have been rewired in plants to meet specific needs. These proteins are currently the focus of intense research in plants due to their involvement in many agronomically important traits, such as seed yield, organ size regulation, biotic and abiotic stress responses, symbiosis, and nitrogen use efficiency. The availability of massive sequence information from a variety of plant species, extensive biochemical data generated over decades, and impressive genetic resources for plant G proteins have made it possible to examine their role, unique properties, and novel regulation. This review focuses on some recent advances in our understanding of the mechanistic details of this critical signaling pathway to enable the precise manipulation and generation of plants to meet future needs.
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Affiliation(s)
- Sona Pandey
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132, USA;
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11
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Miao J, Yang Z, Zhang D, Wang Y, Xu M, Zhou L, Wang J, Wu S, Yao Y, Du X, Gu F, Gong Z, Gu M, Liang G, Zhou Y. Mutation of RGG2, which encodes a type B heterotrimeric G protein γ subunit, increases grain size and yield production in rice. PLANT BIOTECHNOLOGY JOURNAL 2019; 17:650-664. [PMID: 30160362 PMCID: PMC6381795 DOI: 10.1111/pbi.13005] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 08/20/2018] [Accepted: 08/23/2018] [Indexed: 05/22/2023]
Abstract
Heterotrimeric G proteins, which consist of Gα , Gβ and Gγ subunits, function as molecular switches that regulate a wide range of developmental processes in plants. In this study, we characterised the function of rice RGG2, which encodes a type B Gγ subunit, in regulating grain size and yield production. The expression levels of RGG2 were significantly higher than those of other rice Gγ -encoding genes in all tissues tested, suggesting that RGG2 plays essential roles in rice growth and development. By regulating cell expansion, overexpression of RGG2 in Nipponbare (NIP) led to reduced plant height and decreased grain size. By contrast, two mutants generated by the clustered, regularly interspaced, short palindromic repeat (CRISPR)/CRISPR-associated protein 9 (Cas9) system in the Zhenshan 97 (ZS97) background, zrgg2-1 and zrgg2-2, exhibited enhanced growth, including elongated internodes, increased 1000-grain weight and plant biomass and enhanced grain yield per plant (+11.8% and 16.0%, respectively). These results demonstrate that RGG2 acts as a negative regulator of plant growth and organ size in rice. By measuring the length of the second leaf sheath after gibberellin (GA3 ) treatment and the GA-induced α-amylase activity of seeds, we found that RGG2 is also involved in GA signalling. In summary, we propose that RGG2 may regulate grain and organ size via the GA pathway and that manipulation of RGG2 may provide a novel strategy for rice grain yield enhancement.
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Affiliation(s)
- Jun Miao
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co‐Innovation Center for Modern Production Technology of Grain CropsKey Laboratory of Plant Functional Genomics of the Ministry of EducationYangzhou UniversityYangzhouChina
| | - Zefeng Yang
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co‐Innovation Center for Modern Production Technology of Grain CropsKey Laboratory of Plant Functional Genomics of the Ministry of EducationYangzhou UniversityYangzhouChina
| | - Dongping Zhang
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co‐Innovation Center for Modern Production Technology of Grain CropsKey Laboratory of Plant Functional Genomics of the Ministry of EducationYangzhou UniversityYangzhouChina
| | - Yuzhu Wang
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co‐Innovation Center for Modern Production Technology of Grain CropsKey Laboratory of Plant Functional Genomics of the Ministry of EducationYangzhou UniversityYangzhouChina
| | - Mengbin Xu
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co‐Innovation Center for Modern Production Technology of Grain CropsKey Laboratory of Plant Functional Genomics of the Ministry of EducationYangzhou UniversityYangzhouChina
| | - Lihui Zhou
- Institute of Food CropsJiangsu Academy of Agricultural SciencesNanjingChina
| | - Jun Wang
- Institute of Food CropsJiangsu Academy of Agricultural SciencesNanjingChina
| | - Shujun Wu
- Shanghai Academy of Agricultural SciencesShanghaiChina
| | - Youli Yao
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co‐Innovation Center for Modern Production Technology of Grain CropsKey Laboratory of Plant Functional Genomics of the Ministry of EducationYangzhou UniversityYangzhouChina
| | - Xi Du
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co‐Innovation Center for Modern Production Technology of Grain CropsKey Laboratory of Plant Functional Genomics of the Ministry of EducationYangzhou UniversityYangzhouChina
| | - Fangfei Gu
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co‐Innovation Center for Modern Production Technology of Grain CropsKey Laboratory of Plant Functional Genomics of the Ministry of EducationYangzhou UniversityYangzhouChina
| | - Zhiyun Gong
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co‐Innovation Center for Modern Production Technology of Grain CropsKey Laboratory of Plant Functional Genomics of the Ministry of EducationYangzhou UniversityYangzhouChina
| | - Minghong Gu
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co‐Innovation Center for Modern Production Technology of Grain CropsKey Laboratory of Plant Functional Genomics of the Ministry of EducationYangzhou UniversityYangzhouChina
| | - Guohua Liang
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co‐Innovation Center for Modern Production Technology of Grain CropsKey Laboratory of Plant Functional Genomics of the Ministry of EducationYangzhou UniversityYangzhouChina
| | - Yong Zhou
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co‐Innovation Center for Modern Production Technology of Grain CropsKey Laboratory of Plant Functional Genomics of the Ministry of EducationYangzhou UniversityYangzhouChina
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12
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Zheng L, Liu P, Liu Q, Wang T, Dong J. Dynamic Protein S-Acylation in Plants. Int J Mol Sci 2019; 20:ijms20030560. [PMID: 30699892 PMCID: PMC6387154 DOI: 10.3390/ijms20030560] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 01/24/2019] [Accepted: 01/25/2019] [Indexed: 12/13/2022] Open
Abstract
Lipid modification is an important post-translational modification. S-acylation is unique among lipid modifications, as it is reversible and has thus attracted much attention. We summarize some proteins that have been shown experimentally to be S-acylated in plants. Two of these S-acylated proteins have been matched to the S-acyl transferase. More importantly, the first protein thioesterase with de-S-acylation activity has been identified in plants. This review shows that S-acylation is important for a variety of different functions in plants and that there are many unexplored aspects of S-acylation in plants.
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Affiliation(s)
- Lihua Zheng
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
| | - Peng Liu
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
| | - Qianwen Liu
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
| | - Tao Wang
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
| | - Jiangli Dong
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
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13
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Wang S, Xie K, Xu G, Zhou H, Guo Q, Wu J, Liao Z, Liu N, Wang Y, Liu Y. Plant G proteins interact with endoplasmic reticulum luminal protein receptors to regulate endoplasmic reticulum retrieval. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2018; 60:541-561. [PMID: 29573168 DOI: 10.1111/jipb.12648] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2018] [Accepted: 03/12/2018] [Indexed: 06/08/2023]
Abstract
Maintaining endoplasmic reticulum (ER) homeostasis is essential for the production of biomolecules. ER retrieval, i.e., the retrograde transport of compounds from the Golgi to the ER, is one of the pathways that ensures ER homeostasis. However, the mechanisms underlying the regulation of ER retrieval in plants remain largely unknown. Plant ERD2-like proteins (ERD2s) were recently suggested to function as ER luminal protein receptors that mediate ER retrieval. Here, we demonstrate that heterotrimeric G protein signaling is involved in ERD2-mediated ER retrieval. We show that ERD2s interact with the heterotrimeric G protein Gα and Gγ subunits at the Golgi. Silencing of Gα, Gβ, or Gγ increased the retention of ER luminal proteins. Furthermore, overexpression of Gα, Gβ, or Gγ caused ER luminal proteins to escape from the ER, as did the co-silencing of ERD2a and ERD2b. These results suggest that G proteins interact with ER luminal protein receptors to regulate ER retrieval.
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Affiliation(s)
- Shanshan Wang
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Ke Xie
- Advanced Biotechnology and Application Research Center, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Guoyong Xu
- The Institute for Advanced Studies (IAS), Wuhan University, Wuhan 430072, China
| | - Huarui Zhou
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Qiang Guo
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Jingyi Wu
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Zengwei Liao
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Na Liu
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yan Wang
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yule Liu
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
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14
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Pandey S, Vijayakumar A. Emerging themes in heterotrimeric G-protein signaling in plants. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2018; 270:292-300. [PMID: 29576082 DOI: 10.1016/j.plantsci.2018.03.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 01/18/2018] [Accepted: 03/01/2018] [Indexed: 05/28/2023]
Abstract
Heterotrimeric G-proteins are key signaling components involved during the regulation of a multitude of growth and developmental pathways in all eukaryotes. Although the core proteins (Gα, Gβ, Gγ subunits) and their basic biochemistries are conserved between plants and non-plant systems, seemingly different inherent properties of specific components, altered wirings of G-protein network architectures, and the presence of novel receptors and effector proteins make plant G-protein signaling mechanisms somewhat distinct from the well-established animal paradigm. G-protein research in plants is getting a lot of attention recently due to the emerging roles of these proteins in controlling many agronomically important traits. New findings on both canonical and novel G-protein components and their conserved and unique signaling mechanisms are expected to improve our understanding of this important module in affecting critical plant growth and development pathways and eventually their utilization to produce plants for the future needs. In this review, we briefly summarize what is currently known in plant G-protein research, describe new findings and how they are changing our perceptions of the field, and discuss important issues that still need to be addressed.
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Affiliation(s)
- Sona Pandey
- Donald Danforth Plant Science Center, 975 N. Warson Road, St. Louis, MO, 63132, USA.
| | - Anitha Vijayakumar
- Donald Danforth Plant Science Center, 975 N. Warson Road, St. Louis, MO, 63132, USA
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15
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Turnbull D, Hemsley PA. Fats and function: protein lipid modifications in plant cell signalling. CURRENT OPINION IN PLANT BIOLOGY 2017; 40:63-70. [PMID: 28772175 DOI: 10.1016/j.pbi.2017.07.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 07/13/2017] [Accepted: 07/17/2017] [Indexed: 05/12/2023]
Abstract
The post-translational lipid modifications N-myristoylation, prenylation and S-acylation are traditionally associated with increasing protein membrane affinity and localisation. However this is an over-simplification, with evidence now implicating these modifications in a variety of roles such as membrane microdomain partitioning, protein trafficking, protein complex assembly and polarity maintenance. Evidence for a regulatory role is also emerging, with changes or manipulation of lipid modifications offering a means of directly controlling various aspects of protein function. Proteomics advances have revealed an enrichment of signalling proteins in the lipid-modified proteome, potentially indicating an important role for these modifications in responding to stimuli. This review highlights some of the key themes and possible functions of lipid modification during signalling processes in plants.
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Affiliation(s)
- Dionne Turnbull
- Division of Plant Sciences, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, Scotland, UK
| | - Piers A Hemsley
- Division of Plant Sciences, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, Scotland, UK; Cell and Molecular Sciences, The James Hutton Institute, Invergowrie, Dundee DD2 5DA, Scotland, UK.
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16
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Li Y, Qi B. Progress toward Understanding Protein S-acylation: Prospective in Plants. FRONTIERS IN PLANT SCIENCE 2017; 8:346. [PMID: 28392791 PMCID: PMC5364179 DOI: 10.3389/fpls.2017.00346] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2017] [Accepted: 02/28/2017] [Indexed: 05/02/2023]
Abstract
S-acylation, also known as S-palmitoylation or palmitoylation, is a reversible post-translational lipid modification in which long chain fatty acid, usually the 16-carbon palmitate, covalently attaches to a cysteine residue(s) throughout the protein via a thioester bond. It is involved in an array of important biological processes during growth and development, reproduction and stress responses in plant. S-acylation is a ubiquitous mechanism in eukaryotes catalyzed by a family of enzymes called Protein S-Acyl Transferases (PATs). Since the discovery of the first PAT in yeast in 2002 research in S-acylation has accelerated in the mammalian system and followed by in plant. However, it is still a difficult field to study due to the large number of PATs and even larger number of putative S-acylated substrate proteins they modify in each genome. This is coupled with drawbacks in the techniques used to study S-acylation, leading to the slower progress in this field compared to protein phosphorylation, for example. In this review we will summarize the discoveries made so far based on knowledge learnt from the characterization of protein S-acyltransferases and the S-acylated proteins, the interaction mechanisms between PAT and its specific substrate protein(s) in yeast and mammals. Research in protein S-acylation and PATs in plants will also be covered although this area is currently less well studied in yeast and mammalian systems.
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17
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Zavaliev R, Dong X, Epel BL. Glycosylphosphatidylinositol (GPI) Modification Serves as a Primary Plasmodesmal Sorting Signal. PLANT PHYSIOLOGY 2016; 172:1061-1073. [PMID: 27559035 PMCID: PMC5047108 DOI: 10.1104/pp.16.01026] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 08/23/2016] [Indexed: 05/09/2023]
Abstract
Plasmodesmata (Pd) are membranous channels that serve as a major conduit for cell-to-cell communication in plants. The Pd-associated β-1,3-glucanase (BG_pap) and CALLOSE BINDING PROTEIN1 (PDCB1) were identified as key regulators of Pd conductivity. Both are predicted glycosylphosphatidylinositol-anchored proteins (GPI-APs) carrying a conserved GPI modification signal. However, the subcellular targeting mechanism of these proteins is unknown, particularly in the context of other GPI-APs not associated with Pd Here, we conducted a comparative analysis of the subcellular targeting of the two Pd-resident and two unrelated non-Pd GPI-APs in Arabidopsis (Arabidopsis thaliana). We show that GPI modification is necessary and sufficient for delivering both BG_pap and PDCB1 to Pd Moreover, the GPI modification signal from both Pd- and non-Pd GPI-APs is able to target a reporter protein to Pd, likely to plasma membrane microdomains enriched at Pd As such, the GPI modification serves as a primary Pd sorting signal in plant cells. Interestingly, the ectodomain, a region that carries the functional domain in GPI-APs, in Pd-resident proteins further enhances Pd accumulation. However, in non-Pd GPI-APs, the ectodomain overrides the Pd targeting function of the GPI signal and determines a specific GPI-dependent non-Pd localization of these proteins at the plasma membrane and cell wall. Domain-swap analysis showed that the non-Pd localization is also dominant over the Pd-enhancing function mediated by a Pd ectodomain. In conclusion, our results indicate that segregation between Pd- and non-Pd GPI-APs occurs prior to Pd targeting, providing, to our knowledge, the first evidence of the mechanism of GPI-AP sorting in plants.
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Affiliation(s)
- Raul Zavaliev
- Department of Molecular Biology and Ecology of Plants, Tel Aviv University, Tel Aviv 69978, Israel (R.Z., B.L.E.); andDepartment of Biology, Duke University, Durham, North Carolina 27708 (R.Z., X.D.)
| | - Xinnian Dong
- Department of Molecular Biology and Ecology of Plants, Tel Aviv University, Tel Aviv 69978, Israel (R.Z., B.L.E.); andDepartment of Biology, Duke University, Durham, North Carolina 27708 (R.Z., X.D.)
| | - Bernard L Epel
- Department of Molecular Biology and Ecology of Plants, Tel Aviv University, Tel Aviv 69978, Israel (R.Z., B.L.E.); andDepartment of Biology, Duke University, Durham, North Carolina 27708 (R.Z., X.D.)
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18
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Trusov Y, Botella JR. Plant G-Proteins Come of Age: Breaking the Bond with Animal Models. Front Chem 2016; 4:24. [PMID: 27252940 PMCID: PMC4877378 DOI: 10.3389/fchem.2016.00024] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 05/04/2016] [Indexed: 11/29/2022] Open
Abstract
G-proteins are universal signal transducers mediating many cellular responses. Plant G-protein signaling has been modeled on the well-established animal paradigm but accumulated experimental evidence indicates that G-protein-dependent signaling in plants has taken a very different evolutionary path. Here we review the differences between plant and animal G-proteins reported over past two decades. Most importantly, while in animal systems the G-protein signaling cycle is activated by seven transmembrane-spanning G-protein coupled receptors, the existence of these type of receptors in plants is highly controversial. Instead plant G-proteins have been proven to be functionally associated with atypical receptors such as the Arabidopsis RGS1 and a number of receptor-like kinases. We propose that, instead of the GTP/GDP cycle used in animals, plant G-proteins are activated/de-activated by phosphorylation/de-phosphorylation. We discuss the need of a fresh new look at these signaling molecules and provide a hypothetical model that departs from the accepted animal paradigm.
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Affiliation(s)
- Yuri Trusov
- School of Agriculture and Food Sciences, University of Queensland Brisbane, QLD, Australia
| | - José R Botella
- School of Agriculture and Food Sciences, University of Queensland Brisbane, QLD, Australia
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Subramaniam G, Trusov Y, Lopez-Encina C, Hayashi S, Batley J, Botella JR. Type B Heterotrimeric G Protein γ-Subunit Regulates Auxin and ABA Signaling in Tomato. PLANT PHYSIOLOGY 2016; 170:1117-34. [PMID: 26668332 PMCID: PMC4734580 DOI: 10.1104/pp.15.01675] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 12/13/2015] [Indexed: 05/09/2023]
Abstract
Heterotrimeric G proteins composed of α, β, and γ subunits are central signal transducers mediating the cellular response to multiple stimuli in most eukaryotes. Gγ subunits provide proper cellular localization and functional specificity to the heterotrimer complex. Plant Gγ subunits, divided into three structurally distinct types, are more diverse than their animal counterparts. Type B Gγ subunits, lacking a carboxyl-terminal isoprenylation motif, are found only in flowering plants. We present the functional characterization of type B Gγ subunit (SlGGB1) in tomato (Solanum lycopersicum). We show that SlGGB1 is the most abundant Gγ subunit in tomato and strongly interacts with the Gβ subunit. Importantly, the green fluorescent protein-SlGGB1 fusion protein as well as the carboxyl-terminal yellow fluorescent protein-SlGGB1/amino-terminal yellow fluorescent protein-Gβ heterodimer were localized in the plasma membrane, nucleus, and cytoplasm. RNA interference-mediated silencing of SlGGB1 resulted in smaller seeds, higher number of lateral roots, and pointy fruits. The silenced lines were hypersensitive to exogenous auxin, while levels of endogenous auxins were lower or similar to those of the wild type. SlGGB1-silenced plants also showed strong hyposensitivity to abscisic acid (ABA) during seed germination but not in other related assays. Transcriptome analysis of the transgenic seeds revealed abnormal expression of genes involved in ABA sensing, signaling, and response. We conclude that the type B Gγ subunit SlGGB1 mediates auxin and ABA signaling in tomato.
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Affiliation(s)
- Gayathery Subramaniam
- Plant Genetic Engineering Laboratory (G.S., Y.T., J.R.B.) and Centre for Integrative Legume Research (S.H., J.B.), School of Agriculture and Food Sciences, University of Queensland, Brisbane, Queensland 4072, Australia; andInstituto de Horticultura Subtropical y Mediterranea La Mayora, Consejo Superior de Investigaciones Científicas, Universidad de Malaga, Experimental Station La Mayora, 29750 Algarrobo-Costa, Malaga, Spain (C.L.-E.)
| | - Yuri Trusov
- Plant Genetic Engineering Laboratory (G.S., Y.T., J.R.B.) and Centre for Integrative Legume Research (S.H., J.B.), School of Agriculture and Food Sciences, University of Queensland, Brisbane, Queensland 4072, Australia; andInstituto de Horticultura Subtropical y Mediterranea La Mayora, Consejo Superior de Investigaciones Científicas, Universidad de Malaga, Experimental Station La Mayora, 29750 Algarrobo-Costa, Malaga, Spain (C.L.-E.)
| | - Carlos Lopez-Encina
- Plant Genetic Engineering Laboratory (G.S., Y.T., J.R.B.) and Centre for Integrative Legume Research (S.H., J.B.), School of Agriculture and Food Sciences, University of Queensland, Brisbane, Queensland 4072, Australia; andInstituto de Horticultura Subtropical y Mediterranea La Mayora, Consejo Superior de Investigaciones Científicas, Universidad de Malaga, Experimental Station La Mayora, 29750 Algarrobo-Costa, Malaga, Spain (C.L.-E.)
| | - Satomi Hayashi
- Plant Genetic Engineering Laboratory (G.S., Y.T., J.R.B.) and Centre for Integrative Legume Research (S.H., J.B.), School of Agriculture and Food Sciences, University of Queensland, Brisbane, Queensland 4072, Australia; andInstituto de Horticultura Subtropical y Mediterranea La Mayora, Consejo Superior de Investigaciones Científicas, Universidad de Malaga, Experimental Station La Mayora, 29750 Algarrobo-Costa, Malaga, Spain (C.L.-E.)
| | - Jacqueline Batley
- Plant Genetic Engineering Laboratory (G.S., Y.T., J.R.B.) and Centre for Integrative Legume Research (S.H., J.B.), School of Agriculture and Food Sciences, University of Queensland, Brisbane, Queensland 4072, Australia; andInstituto de Horticultura Subtropical y Mediterranea La Mayora, Consejo Superior de Investigaciones Científicas, Universidad de Malaga, Experimental Station La Mayora, 29750 Algarrobo-Costa, Malaga, Spain (C.L.-E.)
| | - José Ramón Botella
- Plant Genetic Engineering Laboratory (G.S., Y.T., J.R.B.) and Centre for Integrative Legume Research (S.H., J.B.), School of Agriculture and Food Sciences, University of Queensland, Brisbane, Queensland 4072, Australia; andInstituto de Horticultura Subtropical y Mediterranea La Mayora, Consejo Superior de Investigaciones Científicas, Universidad de Malaga, Experimental Station La Mayora, 29750 Algarrobo-Costa, Malaga, Spain (C.L.-E.)
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20
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Srivastava V, Weber JR, Malm E, Fouke BW, Bulone V. Proteomic Analysis of a Poplar Cell Suspension Culture Suggests a Major Role of Protein S-Acylation in Diverse Cellular Processes. FRONTIERS IN PLANT SCIENCE 2016; 7:477. [PMID: 27148305 PMCID: PMC4828459 DOI: 10.3389/fpls.2016.00477] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 03/24/2016] [Indexed: 05/03/2023]
Abstract
S-acylation is a reversible post-translational modification of proteins known to be involved in membrane targeting, subcellular trafficking, and the determination of a great variety of functional properties of proteins. The aim of this work was to identify S-acylated proteins in poplar. The use of an acyl-biotin exchange method and mass spectrometry allowed the identification of around 450 S-acylated proteins, which were subdivided into three major groups of proteins involved in transport, signal transduction, and response to stress, respectively. The largest group of S-acylated proteins was the protein kinase superfamily. Soluble N-ethylmaleimide-sensitive factor-activating protein receptors, band 7 family proteins and tetraspanins, all primarily related to intracellular trafficking, were also identified. In addition, cell wall related proteins, including cellulose synthases and other glucan synthases, were found to be S-acylated. Twenty four of the identified S-acylated proteins were also enriched in detergent-resistant membrane microdomains, suggesting S-acylation plays a key role in the localization of proteins to specialized plasma membrane subdomains. This dataset promises to enhance our current understanding of the various functions of S-acylated proteins in plants.
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Affiliation(s)
- Vaibhav Srivastava
- Division of Glycoscience, School of Biotechnology, Royal Institute of Technology, AlbaNova University CentreStockholm, Sweden
- *Correspondence: Vincent Bulone, ; Vaibhav Srivastava,
| | - Joseph R. Weber
- Roy J. Carver Biotechnology Centre, Institute for Genomic Biology, University of Illinois Urbana–ChampaignUrbana, IL, USA
| | - Erik Malm
- Division of Glycoscience, School of Biotechnology, Royal Institute of Technology, AlbaNova University CentreStockholm, Sweden
| | - Bruce W. Fouke
- Roy J. Carver Biotechnology Centre, Institute for Genomic Biology, University of Illinois Urbana–ChampaignUrbana, IL, USA
| | - Vincent Bulone
- Division of Glycoscience, School of Biotechnology, Royal Institute of Technology, AlbaNova University CentreStockholm, Sweden
- ARC Centre of Excellence in Plant Cell Walls and School of Agriculture, Food and Wine, The University of Adelaide, Waite CampusUrrbrae, SA, Australia
- *Correspondence: Vincent Bulone, ; Vaibhav Srivastava,
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Shi W, Zeng Q, Kunkel BN, Running MP. Arabidopsis Rab Geranylgeranyltransferases Demonstrate Redundancy and Broad Substrate Specificity in Vitro. J Biol Chem 2015; 291:1398-410. [PMID: 26589801 DOI: 10.1074/jbc.m115.673491] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Indexed: 11/06/2022] Open
Abstract
Posttranslational lipid modifications mediate the membrane attachment of Rab GTPases, facilitating their function in regulating intracellular vesicular trafficking. In Arabidopsis, most Rab GTPases have two C-terminal cysteines and potentially can be double-geranylgeranylated by heterodimeric Rab geranylgeranyltransferases (Rab-GGTs). Genes encoding two putative α subunits and two putative β subunits of Rab-GGTs have been annotated in the Arabidopsis thaliana genome, but little is known about Rab-GGT activity in Arabidopsis. In this study, we demonstrate that four different heterodimers can be formed between putative Arabidopsis Rab-GGT α subunits RGTA1/RGTA2 and β subunits RGTB1/RGTB2, but only RGTA1·RGTB1 and RGTA1·RGTB2 exhibit bona fide Rab-GGT activity, and they are biochemically redundant in vitro. We hypothesize that RGTA2 function might be disrupted by a 12-amino acid insertion in a conserved motif. We present evidence that Arabidopsis Rab-GGTs may have preference for prenylation of C-terminal cysteines in particular positions. We also demonstrate that Arabidopsis Rab-GGTs can not only prenylate a great variety of Rab GTPases in the presence of Rab escort protein but, unlike Rab-GGT in yeast and mammals, can also prenylate certain non-Rab GTPases independently of Rab escort protein. Our findings may help to explain some of the phenotypes of Arabidopsis protein prenyltransferase mutants.
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Affiliation(s)
- Wan Shi
- From the Department of Biology, Washington University, Saint Louis, Missouri 63130
| | - Qin Zeng
- the Donald Danforth Plant Science Center, Saint Louis, Missouri 63132, and
| | - Barbara N Kunkel
- From the Department of Biology, Washington University, Saint Louis, Missouri 63130
| | - Mark P Running
- the Department of Biology, University of Louisville, Louisville, Kentucky 40292
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Aranda-Sicilia MN, Trusov Y, Maruta N, Chakravorty D, Zhang Y, Botella JR. Heterotrimeric G proteins interact with defense-related receptor-like kinases in Arabidopsis. JOURNAL OF PLANT PHYSIOLOGY 2015; 188:44-8. [PMID: 26414709 DOI: 10.1016/j.jplph.2015.09.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 08/14/2015] [Accepted: 09/09/2015] [Indexed: 05/05/2023]
Abstract
Heterotrimeric G proteins (G-proteins) are versatile signaling elements conserved in Eukaryotes. In animals G-proteins relay signals from 7-transmembrane spanning G protein-coupled receptors (GPCRs) to intracellular downstream effectors; however, the existence of GPCRs in plants is controversial. Contrastingly, a surplus of receptor-like kinases (RLKs) provides signal recognition at the plant cell surface. It is established that G proteins are involved in plant defense and suggested that they relay signals from defense-related RLKs. However, it is unclear how the signaling is conducted, as physical interaction between the RLKs and G proteins has not been demonstrated. Using yeast split-ubiquitin system and Bimolecular Fluorescence Complementation assays, we demonstrate physical interaction between the Gα, Gγ1 and Gγ2 subunits, and the defense-related RD-type receptor like kinases CERK1, BAK1 and BIR1. At the same time, no interaction was detected with the non-RD RLK FLS2. We hypothesize that G-proteins mediate signal transduction immediately downstream of the pathogenesis-related RLKs.
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Affiliation(s)
- María Nieves Aranda-Sicilia
- School of Agriculture and Food Sciences, University of Queensland, Brisbane, QLD 4072, Australia; Current address: Department of Plant Biochemistry, Molecular and Cell Biology, Estación Experimental del Zaidín, CSIC, 18008 Granada, Spain
| | - Yuri Trusov
- School of Agriculture and Food Sciences, University of Queensland, Brisbane, QLD 4072, Australia
| | - Natsumi Maruta
- School of Agriculture and Food Sciences, University of Queensland, Brisbane, QLD 4072, Australia
| | - David Chakravorty
- School of Agriculture and Food Sciences, University of Queensland, Brisbane, QLD 4072, Australia; Current address: Biology Department, Pennsylvania State University, University Park, PA 16802, USA
| | - Yuelin Zhang
- Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - José Ramón Botella
- School of Agriculture and Food Sciences, University of Queensland, Brisbane, QLD 4072, Australia.
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23
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Konrad SSA, Ott T. Molecular principles of membrane microdomain targeting in plants. TRENDS IN PLANT SCIENCE 2015; 20:351-61. [PMID: 25936559 DOI: 10.1016/j.tplants.2015.03.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2014] [Revised: 03/24/2015] [Accepted: 03/26/2015] [Indexed: 05/19/2023]
Abstract
Plasma membranes (PMs) are heterogeneous lipid bilayers comprising diverse subdomains. These sites can be labeled by various proteins in vivo and may serve as hotspots for signal transduction. They are found at apical, basal, and lateral membranes of polarized cells, at cell equatorial planes, or almost isotropically distributed throughout the PM. Recent advances in imaging technologies and understanding of mechanisms that allow proteins to target specific sites in PMs have provided insights into the dynamics and complexity of their specific segregation. Here we present a comprehensive overview of the different types of membrane microdomain and describe the molecular modes that determine site-directed targeting of membrane-resident proteins at the PM.
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Affiliation(s)
- Sebastian S A Konrad
- Ludwig-Maximilians-Universität München, Genetics, Großhaderner Str. 2-4, 82152 Planegg-Martinsried, Germany
| | - Thomas Ott
- Ludwig-Maximilians-Universität München, Genetics, Großhaderner Str. 2-4, 82152 Planegg-Martinsried, Germany.
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24
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Maruta N, Trusov Y, Brenya E, Parekh U, Botella JR. Membrane-localized extra-large G proteins and Gbg of the heterotrimeric G proteins form functional complexes engaged in plant immunity in Arabidopsis. PLANT PHYSIOLOGY 2015; 167:1004-16. [PMID: 25588736 PMCID: PMC4348786 DOI: 10.1104/pp.114.255703] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
In animals, heterotrimeric G proteins, comprising Ga, Gb, and Gg subunits, are molecular switches whose function tightly depends on Ga and Gbg interaction. Intriguingly, in Arabidopsis (Arabidopsis thaliana), multiple defense responses involve Gbg, but not Ga. We report here that the Gbg dimer directly partners with extra-large G proteins (XLGs) to mediate plant immunity. Arabidopsis mutants deficient in XLGs, Gb, and Gg are similarly compromised in several pathogen defense responses, including disease development and production of reactive oxygen species. Genetic analysis of double, triple, and quadruple mutants confirmed that XLGs and Gbg functionally interact in the same defense signaling pathways. In addition, mutations in XLG2 suppressed the seedling lethal and cell death phenotypes of BRASSINOSTEROID INSENSITIVE1-associated receptor kinase1-interacting receptor-like kinase1 mutants in an identical way as reported for Arabidopsis Gb-deficient mutants. Yeast (Saccharomyces cerevisiae) three-hybrid and bimolecular fluorescent complementation assays revealed that XLG2 physically interacts with all three possible Gbg dimers at the plasma membrane. Phylogenetic analysis indicated a close relationship between XLGs and plant Ga subunits, placing the divergence point at the dawn of land plant evolution. Based on these findings, we conclude that XLGs form functional complexes with Gbg dimers, although the mechanism of action of these complexes, including activation/deactivation, must be radically different form the one used by the canonical Ga subunit and are not likely to share the same receptors. Accordingly, XLGs expand the repertoire of heterotrimeric G proteins in plants and reveal a higher level of diversity in heterotrimeric G protein signaling.
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25
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Hurst CH, Hemsley PA. Current perspective on protein S-acylation in plants: more than just a fatty anchor? JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:1599-606. [PMID: 25725093 DOI: 10.1093/jxb/erv053] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Membranes are an important signalling platform in plants. The plasma membrane is the point where information about the external environment must be converted into intracellular signals, while endomembranes are important sites of protein trafficking, organization, compartmentalization, and intracellular signalling. This requires co-ordinating the spatial distribution of proteins, their activation state, and their interacting partners. This regulation frequently occurs through post-translational modification of proteins. Proteins that associate with the cell membrane do so through transmembrane domains, protein-protein interactions, lipid binding motifs/domains or use the post-translational addition of lipid groups as prosthetic membrane anchors. S-acylation is one such lipid modification capable of anchoring proteins to the membrane. Our current knowledge of S-acylation function in plants is fairly limited compared with other post-translational modifications and S-acylation in other organisms. However, it is becoming increasingly clear that S-acylation can act as more than just a simple membrane anchor: it can also act as a regulatory mechanism in signalling pathways in plants. S-acylation is, therefore, an ideal mechanism for regulating protein function at membranes. This review discusses our current knowledge of S-acylated proteins in plants, the interaction of different lipid modifications, and the general effects of S-acylation on cellular function.
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Affiliation(s)
- Charlotte H Hurst
- Division of Plant Sciences, University of Dundee, The James Hutton Institute, Invergowrie, Dundee DD2 5DA, uk Cell and molecular sciences, The James Hutton Institute, Invergowrie, Dundee DD2 5DA, K
| | - Piers A Hemsley
- Division of Plant Sciences, University of Dundee, The James Hutton Institute, Invergowrie, Dundee DD2 5DA, uk Cell and molecular sciences, The James Hutton Institute, Invergowrie, Dundee DD2 5DA, K
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26
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Zhang YL, Li E, Feng QN, Zhao XY, Ge FR, Zhang Y, Li S. Protein palmitoylation is critical for the polar growth of root hairs in Arabidopsis. BMC PLANT BIOLOGY 2015; 15:50. [PMID: 25849075 PMCID: PMC4340681 DOI: 10.1186/s12870-015-0441-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 01/23/2015] [Indexed: 05/19/2023]
Abstract
BACKGROUND Protein palmitoylation, which is critical for membrane association and subcellular targeting of many signaling proteins, is catalyzed mainly by protein S-acyl transferases (PATs). Only a few plant proteins have been experimentally verified to be subject to palmitoylation, such as ROP GTPases, calcineurin B like proteins (CBLs), and subunits of heterotrimeric G proteins. However, emerging evidence from palmitoyl proteomics hinted that protein palmitoylation as a post-translational modification might be widespread. Nonetheless, due to the large number of genes encoding PATs and the lack of consensus motifs for palmitoylation, progress on the roles of protein palmitoylation in plants has been slow. RESULTS We combined pharmacological and genetic approaches to examine the role of protein palmitoylation in root hair growth. Multiple PATs from different endomembrane compartments may participate in root hair growth, among which the Golgi-localized PAT24/TIP GROWTH DEFECTIVE1 (TIP1) plays a major role while the tonoplast-localized PAT10 plays a secondary role in root hair growth. A specific inhibitor for protein palmitoylation, 2-bromopalmitate (2-BP), compromised root hair elongation and polarity. Using various probes specific for cellular processes, we demonstrated that 2-BP impaired the dynamic polymerization of actin microfilaments (MF), the asymmetric plasma membrane (PM) localization of phosphatidylinositol (4,5)-bisphosphate (PIP2), the dynamic distribution of RabA4b-positive post-Golgi secretion, and endocytic trafficking in root hairs. CONCLUSIONS By combining pharmacological and genetic approaches and using root hairs as a model, we show that protein palmitoylation, regulated by protein S-acyl transferases at different endomembrane compartments such as the Golgi and the vacuole, is critical for the polar growth of root hairs in Arabidopsis. Inhibition of protein palmitoylation by 2-BP disturbed key intracellular activities in root hairs. Although some of these effects are likely indirect, the cytological data reported here will contribute to a deep understanding of protein palmitoylation during tip growth in plants.
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Affiliation(s)
- Yu-Ling Zhang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai’an, 271018 China
| | - En Li
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai’an, 271018 China
| | - Qiang-Nan Feng
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai’an, 271018 China
| | - Xin-Ying Zhao
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai’an, 271018 China
| | - Fu-Rong Ge
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai’an, 271018 China
| | - Yan Zhang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai’an, 271018 China
| | - Sha Li
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai’an, 271018 China
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27
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Wolfenstetter S, Chakravorty D, Kula R, Urano D, Trusov Y, Sheahan MB, McCurdy DW, Assmann SM, Jones AM, Botella JR. Evidence for an unusual transmembrane configuration of AGG3, a class C Gγ subunit of Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2015; 81:388-98. [PMID: 25430066 PMCID: PMC4334566 DOI: 10.1111/tpj.12732] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 11/19/2014] [Accepted: 11/21/2014] [Indexed: 05/20/2023]
Abstract
Heterotrimeric G proteins are crucial for the perception of external signals and subsequent signal transduction in animal and plant cells. In both model systems, the complex comprises one Gα, one Gβ, and one Gγ subunit. However, in addition to the canonical Gγ subunits (class A), plants also possess two unusual, plant-specific classes of Gγ subunits (classes B and C) that have not yet been found in animals. These include Gγ subunits lacking the C-terminal CaaX motif (class B), which is important for membrane anchoring of the protein; the presence of such subunits gives rise to a flexible sub-population of Gβ/γ heterodimers that are not necessarily restricted to the plasma membrane. Plants also contain class C Gγ subunits, which are twice the size of canonical Gγ subunits, with a predicted transmembrane domain and a large cysteine-rich extracellular C-terminus. However, neither the presence of the transmembrane domain nor the membrane topology have been unequivocally demonstrated. Here, we provide compelling evidence that AGG3, a class C Gγ subunit of Arabidopsis, contains a functional transmembrane domain, which is sufficient but not essential for plasma membrane localization, and that the cysteine-rich C-terminus is extracellular.
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Affiliation(s)
- Susanne Wolfenstetter
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, United States of America
| | - David Chakravorty
- Plant Genetic Engineering Laboratory, School of Agriculture and Food Sciences, University of Queensland, Brisbane 4072, Australia
- Biology Department, 208 Mueller Laboratory, Pennsylvania State University, University Park, PA 16802, USA
| | - Ryan Kula
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, United States of America
| | - Daisuke Urano
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, United States of America
| | - Yuri Trusov
- Plant Genetic Engineering Laboratory, School of Agriculture and Food Sciences, University of Queensland, Brisbane 4072, Australia
| | - Michael B. Sheahan
- School of Environmental and Life Sciences, University of Newcastle, Callaghan, New South Wales, 2308 Australia
| | - David W. McCurdy
- School of Environmental and Life Sciences, University of Newcastle, Callaghan, New South Wales, 2308 Australia
| | - Sarah M. Assmann
- Biology Department, 208 Mueller Laboratory, Pennsylvania State University, University Park, PA 16802, USA
| | - Alan M. Jones
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, United States of America
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC 27599, United States of America
- To whom correspondence should be addressed.
| | - Jose R. Botella
- Plant Genetic Engineering Laboratory, School of Agriculture and Food Sciences, University of Queensland, Brisbane 4072, Australia
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28
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Gui J, Zheng S, Shen J, Li L. Grain setting defect1 (GSD1) function in rice depends on S-acylation and interacts with actin 1 (OsACT1) at its C-terminal. FRONTIERS IN PLANT SCIENCE 2015; 6:804. [PMID: 26483819 PMCID: PMC4590517 DOI: 10.3389/fpls.2015.00804] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 09/15/2015] [Indexed: 05/19/2023]
Abstract
Grain setting defect1 (GSD1), a plant-specific remorin protein specifically localized at the plasma membrane (PM) and plasmodesmata of phloem companion cells, affects grain setting in rice through regulating the transport of photoassimilates. Here, we show new evidence demonstrating that GSD1 is localized at the cytoplasmic face of the PM and a stretch of 45 amino acid residues at its C-terminal is required for its localization. Association with the PM is mediated by S-acylation of cysteine residues Cys-524 and Cys-527, in a sequence of 45 amino acid residues essential for GSD1 function in rice. Furthermore, the coiled-coil domain in GSD1 is necessary for sufficient interaction with OsACT1. Together, these results reveal that GSD1 attaches to the PM through S-acylation and interacts with OsACT1 through its coiled-coil domain structure to regulate plasmodesmata conductance for photoassimilate transport in rice.
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Affiliation(s)
| | | | | | - Laigeng Li
- *Correspondence: Laigeng Li, National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China,
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29
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Hemsley PA. The importance of lipid modified proteins in plants. THE NEW PHYTOLOGIST 2015; 205:476-89. [PMID: 25283240 DOI: 10.1111/nph.13085] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Accepted: 08/22/2014] [Indexed: 05/18/2023]
Abstract
Membranes have long been known to act as more than physical barriers within and between plant cells. Trafficking of membrane proteins, signalling from and across membranes, organisation of membranes and transport through membranes are all essential processes for plant cellular function. These processes rely on a myriad array of proteins regulated in a variety of manners and are frequently required to be directly associated with membranes. For integral membrane proteins, the mode of membrane association is readily apparent, but many peripherally associated membrane proteins are outwardly soluble proteins. In these cases the proteins are frequently modified by the addition of lipids allowing direct interaction with the hydrophobic core of membranes. These modifications include N-myristoylation, S-acylation (palmitoylation), prenylation and GPI anchors but until recently little was truly known about their function in plants. New data suggest that these modifications are able to act as more than just membrane anchors, and dynamic S-acylation in particular is emerging as a means of regulating protein function in a similar manner to phosphorylation. This review discusses how these modifications occur, their impact on protein function, how they are regulated, recent advances in the field and technical approaches for studying these modifications.
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Affiliation(s)
- Piers A Hemsley
- Division of Plant Sciences, University of Dundee, Dundee, UK; Cell and Molecular Sciences, The James Hutton Institute, Dundee, UK
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30
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Thole JM, Perroud PF, Quatrano RS, Running MP. Prenylation is required for polar cell elongation, cell adhesion, and differentiation in Physcomitrella patens. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2014; 78:441-451. [PMID: 24634995 DOI: 10.1111/tpj.12484] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Revised: 01/16/2014] [Accepted: 02/12/2014] [Indexed: 06/03/2023]
Abstract
Protein prenylation is required for a variety of growth and developmental processes in flowering plants. Here we report the consequences of loss of function of all known prenylation subunits in the moss Physcomitrella patens. As in Arabidopsis, protein farnesyltransferase and protein geranylgeranyltransferase type I are not required for viability. However, protein geranylgeranyltransferase type I activity is required for cell adhesion, polar cell elongation, and cell differentiation. Loss of protein geranylgeranyltransferase activity results in colonies of round, single-celled organisms that resemble unicellular algae. The loss of protein farnesylation is not as severe but also results in polar cell elongation and differentiation defects. The complete loss of Rab geranylgeranyltransferase activity appears to be lethal in P. patens. Labeling with antibodies to cell wall components support the lack of polarity establishment and the undifferentiated state of geranylgeranyltransferase type I mutant plants. Our results show that prenylated proteins play key roles in P. patens development and differentiation processes.
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Affiliation(s)
- Julie M Thole
- Donald Danforth Plant Science Center, 975 N Warson Road, Saint Louis, MO, 63132, USA
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31
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Running MP. The role of lipid post-translational modification in plant developmental processes. FRONTIERS IN PLANT SCIENCE 2014; 5:50. [PMID: 24600462 PMCID: PMC3927097 DOI: 10.3389/fpls.2014.00050] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2013] [Accepted: 02/01/2014] [Indexed: 05/06/2023]
Abstract
Most eukaryotic proteins are post-translationally modified, and modification has profound effects on protein function. One key modification is the attachment of a lipid group to certain amino acids; this typically facilitates subcellular targeting (association with a membrane) and protein-protein interactions (by virtue of the large hydrophobic moiety). Most widely recognized are lipid modifications of proteins involved in developmental signaling, but proteins with structural roles are also lipid-modified. The three known types of intracellular protein lipid modifications are S-acylation, N-myristoylation, and prenylation. In plants, genetic analysis of the enzymes involved, along with molecular analysis of select target proteins, has recently shed light on the roles of lipid modification in key developmental processes, such as meristem function, flower development, polar cell elongation, cell differentiation, and hormone responses. In addition, while lipid post-translational mechanisms are generally conserved among eukaryotes, plants differ in the nature and function of target proteins, the effects of lipid modification on target proteins, and the roles of lipid modification in developmental processes.
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Affiliation(s)
- Mark P. Running
- *Correspondence: Mark P. Running, Department of Biology, University of Louisville, Louisville, KY 40292, USA e-mail:
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32
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Qi B, Doughty J, Hooley R. A Golgi and tonoplast localized S-acyl transferase is involved in cell expansion, cell division, vascular patterning and fertility in Arabidopsis. THE NEW PHYTOLOGIST 2013; 200:444-456. [PMID: 23795888 PMCID: PMC3817529 DOI: 10.1111/nph.12385] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Accepted: 05/23/2013] [Indexed: 05/04/2023]
Abstract
S-acylation of eukaryotic proteins is the reversible attachment of palmitic or stearic acid to cysteine residues, catalysed by protein S-acyl transferases that share an Asp-His-His-Cys (DHHC) motif. Previous evidence suggests that in Arabidopsis S-acylation is involved in the control of cell size, polarity and the growth of pollen tubes and root hairs. Using a combination of yeast genetics, biochemistry, cell biology and loss of function genetics the roles of a member of the protein S-acyl transferase PAT family, AtPAT10 (At3g51390), have been explored. In keeping with its role as a PAT, AtPAT10 auto-S-acylates, and partially complements the yeast akr1 PAT mutant, and this requires Cys(192) of the DHHC motif. In Arabidopsis AtPAT10 is localized in the Golgi stack, trans-Golgi network/early endosome and tonoplast. Loss-of-function mutants have a pleiotropic phenotype involving cell expansion and division, vascular patterning, and fertility that is rescued by wild-type AtPAT10 but not by catalytically inactive AtPAT10C(192) A. This supports the hypothesis that AtPAT10 is functionally independent of the other Arabidopsis PATs. Our findings demonstrate a growing importance of protein S-acylation in plants, and reveal a Golgi and tonoplast located S-acylation mechanism that affects a range of events during growth and development in Arabidopsis.
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Affiliation(s)
- Baoxiu Qi
- Department of Biology and Biochemistry, University of BathClaverton Down, Bath, BA2 7AY, UK
- State Key Laboratory of Crop Biology, Shandong Agricultural UniversityShandong, 271018, China
| | - James Doughty
- Department of Biology and Biochemistry, University of BathClaverton Down, Bath, BA2 7AY, UK
| | - Richard Hooley
- Department of Biology and Biochemistry, University of BathClaverton Down, Bath, BA2 7AY, UK
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33
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Hemsley PA, Weimar T, Lilley K, Dupree P, Grierson C. Palmitoylation in plants: new insights through proteomics. PLANT SIGNALING & BEHAVIOR 2013; 8:25209. [PMID: 23759553 PMCID: PMC3999067 DOI: 10.4161/psb.25209] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Accepted: 05/29/2013] [Indexed: 05/20/2023]
Abstract
Palmitoylation is the post-translational addition of lipids to proteins though thioester bonds and acts to promote association with membranes. Palmitoylation also acts to target proteins to specific membrane compartments, control residence in and movement between membrane microdomains and regulate protein conformation and activity. Palmitoylation is unique among lipid modifications of proteins as it is reversible, allowing for dynamic control over all palmitoylation dependent processes. Palmitoylation cannot be predicted from protein sequence and as a result is understudied when compared with other post-translational modifications. We recently published a proteomic analysis of palmitoylation in plants and increased the number of proposed palmitoylated proteins in plants from ~30 to over 500. The wide range of identified proteins indicates that palmitoylation is likely important for a variety of different functions in plants. Many supposedly well characterized proteins were identified as palmitoylated and our new data provides novel insight into regulatory mechanisms and potential explanations for observed phenomena. These data represent a new resource for plant biologist and will allow the study of palmitoylated proteins in plants to expand and move forward.
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Affiliation(s)
- Piers A. Hemsley
- Division of Plant Sciences; University of Dundee at the James Hutton Institute; Invergowrie, UK
- Cell and Molecular Sciences; James Hutton Institute; Invergowrie, UK
- Correspondence to: Piers A. Hemsley,
| | - Thilo Weimar
- Department of Biochemistry; University of Cambridge; Cambridge, UK
| | - Kathryn Lilley
- Cambridge Center for Proteomics; University of Cambridge; Cambridge, UK
| | - Paul Dupree
- Department of Biochemistry; University of Cambridge; Cambridge, UK
| | - Claire Grierson
- School of Biological Sciences; University of Bristol; Bristol, UK
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34
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Thung L, Chakravorty D, Trusov Y, Jones AM, Botella JR. Signaling specificity provided by the Arabidopsis thaliana heterotrimeric G-protein γ subunits AGG1 and AGG2 is partially but not exclusively provided through transcriptional regulation. PLoS One 2013; 8:e58503. [PMID: 23520518 PMCID: PMC3592790 DOI: 10.1371/journal.pone.0058503] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Accepted: 02/05/2013] [Indexed: 11/18/2022] Open
Abstract
The heterotrimeric G-protein complex in Arabidopsis thaliana consists of one α, one ß and three γ subunits. While two of the γ subunits, AGG1 and AGG2 have been shown to provide functional selectivity to the Gßγ dimer in Arabidopsis, it is unclear if such selectivity is embedded in their molecular structures or conferred by the different expression patterns observed in both subunits. In order to study the molecular basis for such selectivity we tested genetic complementation of AGG1- and AGG2 driven by the respectively swapped gene promoters. When expressed in the same tissues as AGG1, AGG2 rescues some agg1 mutant phenotypes such as the hypersensitivity to Fusarium oxysporum and D-mannitol as well as the altered levels of lateral roots, but does not rescue the early flowering phenotype. Similarly, AGG1 when expressed in the same tissues as AGG2 rescues the osmotic stress and lateral-root phenotypes observed in agg2 mutants but failed to rescue the heat-stress induction of flowering. The fact that AGG1 and AGG2 are functionally interchangeable in some pathways implies that, at least for those pathways, signaling specificity resides in the distinctive spatiotemporal expression patterns exhibited by each γ subunit. On the other hand, the lack of complementation for some phenotypes indicates that there are pathways in which signaling specificity is provided by differences in the primary AGG1 and AGG2 amino acid sequences.
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Affiliation(s)
- Leena Thung
- Plant Genetic Engineering Laboratory, School of Agriculture and Food Sciences, University of Queensland, Brisbane, Queensland, Australia
| | - David Chakravorty
- Plant Genetic Engineering Laboratory, School of Agriculture and Food Sciences, University of Queensland, Brisbane, Queensland, Australia
| | - Yuri Trusov
- Plant Genetic Engineering Laboratory, School of Agriculture and Food Sciences, University of Queensland, Brisbane, Queensland, Australia
| | - Alan M. Jones
- Departments of Biology and Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - José Ramón Botella
- Plant Genetic Engineering Laboratory, School of Agriculture and Food Sciences, University of Queensland, Brisbane, Queensland, Australia
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35
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Zhou LZ, Li S, Feng QN, Zhang YL, Zhao X, Zeng YL, Wang H, Jiang L, Zhang Y. Protein S-ACYL Transferase10 is critical for development and salt tolerance in Arabidopsis. THE PLANT CELL 2013; 25:1093-107. [PMID: 23482856 PMCID: PMC3634679 DOI: 10.1105/tpc.112.108829] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Revised: 02/11/2013] [Accepted: 02/17/2013] [Indexed: 05/18/2023]
Abstract
Protein S-acylation, commonly known as palmitoylation, is a reversible posttranslational modification that catalyzes the addition of a saturated lipid group, often palmitate, to the sulfhydryl group of a Cys. Palmitoylation regulates enzyme activity, protein stability, subcellular localization, and intracellular sorting. Many plant proteins are palmitoylated. However, little is known about protein S-acyl transferases (PATs), which catalyze palmitoylation. Here, we report that the tonoplast-localized PAT10 is critical for development and salt tolerance in Arabidopsis thaliana. PAT10 loss of function resulted in pleiotropic growth defects, including smaller leaves, dwarfism, and sterility. In addition, pat10 mutants are hypersensitive to salt stresses. We further show that PAT10 regulates the tonoplast localization of several calcineurin B-like proteins (CBLs), including CBL2, CBL3, and CBL6, whose membrane association also depends on palmitoylation. Introducing a C192S mutation within the highly conserved catalytic motif of PAT10 failed to complement pat10 mutants, indicating that PAT10 functions through protein palmitoylation. We propose that PAT10-mediated palmitoylation is critical for vacuolar function by regulating membrane association or the activities of tonoplast proteins.
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Affiliation(s)
- Liang-Zi Zhou
- State Key Laboratory of Crop Biology, Shandong Agricultural University, Tai'an 271018, Shandong, China
| | - Sha Li
- State Key Laboratory of Crop Biology, Shandong Agricultural University, Tai'an 271018, Shandong, China
| | - Qiang-Nan Feng
- State Key Laboratory of Crop Biology, Shandong Agricultural University, Tai'an 271018, Shandong, China
| | - Yu-Ling Zhang
- State Key Laboratory of Crop Biology, Shandong Agricultural University, Tai'an 271018, Shandong, China
| | - Xinying Zhao
- State Key Laboratory of Crop Biology, Shandong Agricultural University, Tai'an 271018, Shandong, China
| | - Yong-lun Zeng
- School of Life Sciences, Centre for Cell and Developmental Biology, The Chinese University of Hong Kong, Hong Kong 999077, China
| | - Hao Wang
- School of Life Sciences, Centre for Cell and Developmental Biology, The Chinese University of Hong Kong, Hong Kong 999077, China
| | - Liwen Jiang
- School of Life Sciences, Centre for Cell and Developmental Biology, The Chinese University of Hong Kong, Hong Kong 999077, China
| | - Yan Zhang
- State Key Laboratory of Crop Biology, Shandong Agricultural University, Tai'an 271018, Shandong, China
- Address correspondence to
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Hemsley PA, Weimar T, Lilley KS, Dupree P, Grierson CS. A proteomic approach identifies many novel palmitoylated proteins in Arabidopsis. THE NEW PHYTOLOGIST 2013; 197:805-814. [PMID: 23252521 DOI: 10.1111/nph.12077] [Citation(s) in RCA: 103] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Accepted: 10/31/2012] [Indexed: 05/06/2023]
Abstract
S-acylation (palmitoylation) is a poorly understood post-translational modification of proteins involving the addition of acyl lipids to cysteine residues. S-acylation promotes the association of proteins with membranes and influences protein stability, microdomain partitioning, membrane targeting and activation state. No consensus motif for S-acylation exists and it therefore requires empirical identification. Here, we describe a biotin switch isobaric tagging for relative and absolute quantification (iTRAQ)-based method to identify S-acylated proteins from Arabidopsis. We use these data to predict and confirm S-acylation of proteins not in our dataset. We identified c. 600 putative S-acylated proteins affecting diverse cellular processes. These included proteins involved in pathogen perception and response, mitogen-activated protein kinases (MAPKs), leucine-rich repeat receptor-like kinases (LRR-RLKs) and RLK superfamily members, integral membrane transporters, ATPases, soluble N-ethylmaleimide-sensitive factor-activating protein receptors (SNAREs) and heterotrimeric G-proteins. The prediction of S-acylation of related proteins was demonstrated by the identification and confirmation of S-acylation sites within the SNARE and LRR-RLK families. We showed that S-acylation of the LRR-RLK FLS2 is required for a full response to elicitation by the flagellin derived peptide flg22, but is not required for localization to the plasma membrane. Arabidopsis contains many more S-acylated proteins than previously thought. These data can be used to identify S-acylation sites in related proteins. We also demonstrated that S-acylation is required for full LRR-RLK function.
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Affiliation(s)
- Piers A Hemsley
- School of Biological Science, University of Bristol, Woodland Road, Bristol, BS8 1UG, UK
| | - Thilo Weimar
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Kathryn S Lilley
- Cambridge Centre for Proteomics, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QR, UK
| | - Paul Dupree
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Claire S Grierson
- School of Biological Science, University of Bristol, Woodland Road, Bristol, BS8 1UG, UK
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Abstract
Protein prenylation, like other lipid posttranslational modifications of eukaryotic proteins, plays important roles in protein-membrane association and protein-protein interactions. In Arabidopsis, hundreds of proteins involved in a great variety of biological processes are potential prenylation substrates that need to be verified, including heterotrimeric G proteins and most Rop and Rab small GTPases. Also, genetic evidence suggests substrate cross-specificity among different prenyltransferases and/or the existence of unidentified prenylation players. In this chapter we describe a direct and flexible in vitro enzymatic assay designed for testing prenylation activity and substrate specificity in vitro. This protocol takes Arabidopsis Rab-GGT as example and starts with preparation of purified protein components of the reaction, followed by reconstitution of the prenylation reaction in vitro, and autoradiographic detection for qualitative and semiquantitative analysis.
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Affiliation(s)
- Wan Shi
- Washington University in Saint Louis, St. Louis, MO, USA
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Abstract
S-acylation is increasingly being recognized as an important posttranslational modification of proteins controlling activity, subcellular localization, microdomain residence, and stability. Heterotrimeric G-proteins and GPCRs are particularly well studied S-acylated proteins, and fast, cheap, reliable methods are required for the analysis of S-acylation states of these proteins. Various approaches have been developed to study S-acylation, but they are time consuming, expensive, frequently require radiolabels and generally only suitable for cell culture, making them impractical for work in plant systems. Here a rapid and inexpensive method is described for the analysis of the S-acylation state of AGG2 that can be performed on any cell or tissue sample using standard laboratory equipment and methods. This method is also applicable to any protein that can be detected by western blotting.
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Affiliation(s)
- Piers A Hemsley
- Division of Plant Sciences, College of Life Sciences, University of Dundee, Dundee, UK
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Sorek N, Akerman A, Yalovsky S. Analysis of protein prenylation and S-acylation using gas chromatography-coupled mass spectrometry. Methods Mol Biol 2013; 1043:121-134. [PMID: 23913042 DOI: 10.1007/978-1-62703-532-3_13] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Lipid modifications play a key role in protein targeting and function. The two Arabidopsis Gγ subunits, AGG1 and AGG2, have been shown to undergo prenylation (AGG1) and S-acylation (AGG2). Prenylation involves covalent nonreversible attachment of either farnesyl (15 carbons) or geranylgeranyl (20 carbons) isoprenoids to conserved cysteine residues at or near the C-terminus of proteins. S-acylation, frequently referred to as palmitoylation, involves the attachment of acyl fatty acids to thiol groups of cysteine residues through a reversible thioester bond. The procedures described below allow direct analysis of the prenyl and acyl moieties using gas chromatography-coupled mass spectrometry (GC-MS). These methods are based on (1) cleavage of prenyl groups with the Raney nickel catalyst and (2) analysis of protein S-acylation following cleavage of the acyl fatty acids from proteins by hydrogenation with platinum (IV) oxide. The hydrogenation under these conditions causes an acid transesterification of the acyl moieties, adding an ethyl group to the carboxyl head of the fatty acid. The addition of the ethyl group reduces the polarity of the fatty acids, allowing their efficient separation by gas chromatography.
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Affiliation(s)
- Nadav Sorek
- Energy Biosciences Institute, Berkeley, CA, USA
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Batistic O. Genomics and localization of the Arabidopsis DHHC-cysteine-rich domain S-acyltransferase protein family. PLANT PHYSIOLOGY 2012; 160:1597-612. [PMID: 22968831 PMCID: PMC3490592 DOI: 10.1104/pp.112.203968] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Accepted: 09/07/2012] [Indexed: 05/18/2023]
Abstract
Protein lipid modification of cysteine residues, referred to as S-palmitoylation or S-acylation, is an important secondary and reversible modification that regulates membrane association, trafficking, and function of target proteins. This enzymatic reaction is mediated by protein S-acyl transferases (PATs). Here, the phylogeny, genomic organization, protein topology, expression, and localization pattern of the 24 PAT family members from Arabidopsis (Arabidopsis thaliana) is described. Most PATs are expressed at ubiquitous levels and tissues throughout the development, while few genes are expressed especially during flower development preferentially in pollen and stamen. The proteins display large sequence and structural variations but exhibit a common protein topology that is preserved in PATs from various organisms. Arabidopsis PAT proteins display a complex targeting pattern and were detected at the endoplasmic reticulum, Golgi, endosomal compartments, and the vacuolar membrane. However, most proteins were targeted to the plasma membrane. This large concentration of plant PAT activity to the plasma membrane suggests that the plant cellular S-acylation machinery is functionally different compared with that of yeast (Saccharomyces cerevisiae) and mammalians.
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Affiliation(s)
- Oliver Batistic
- Institut für Biologie und Biotechnologie der Pflanzen, Universität Münster, 48149 Muenster, Germany.
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41
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Trusov Y, Chakravorty D, Botella JR. Diversity of heterotrimeric G-protein γ subunits in plants. BMC Res Notes 2012; 5:608. [PMID: 23113884 PMCID: PMC3508898 DOI: 10.1186/1756-0500-5-608] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Accepted: 10/15/2012] [Indexed: 12/13/2022] Open
Abstract
Background Heterotrimeric G-proteins, consisting of three subunits Gα, Gβ and Gγ are present in most eukaryotes and mediate signaling in numerous biological processes. In plants, Gγ subunits were shown to provide functional selectivity to G-proteins. Three unconventional Gγ subunits were recently reported in Arabidopsis, rice and soybean but no structural analysis has been reported so far. Their relationship with conventional Gγ subunits and taxonomical distribution has not been yet demonstrated. Results After an extensive similarity search through plant genomes, transcriptomes and proteomes we assembled over 200 non-redundant proteins related to the known Gγ subunits. Structural analysis of these sequences revealed that most of them lack the obligatory C-terminal prenylation motif (CaaX). According to their C-terminal structures we classified the plant Gγ subunits into three distinct types. Type A consists of Gγ subunits with a putative prenylation motif. Type B subunits lack a prenylation motif and do not have any cysteine residues in the C-terminal region, while type C subunits contain an extended C-terminal domain highly enriched with cysteines. Comparative analysis of C-terminal domains of the proteins, intron-exon arrangement of the corresponding genes and phylogenetic studies suggested a common origin of all plant Gγ subunits. Conclusion Phylogenetic analyses suggest that types C and B most probably originated independently from type A ancestors. We speculate on a potential mechanism used by those Gγ subunits lacking isoprenylation motifs to anchor the Gβγ dimer to the plasma membrane and propose a new flexible nomenclature for plant Gγ subunits. Finally, in the light of our new classification, we give a word of caution about the interpretation of Gγ research in Arabidopsis and its generalization to other plant species.
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Affiliation(s)
- Yuri Trusov
- Plant Genetic Engineering Laboratory, School of Agriculture and Food Sciences, University of Queensland, Brisbane, Queensland, 4072, Australia
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Li S, Liu W, Zhang X, Liu Y, Li N, Li Y. Roles of the Arabidopsis G protein γ subunit AGG3 and its rice homologs GS3 and DEP1 in seed and organ size control. PLANT SIGNALING & BEHAVIOR 2012; 7:1357-9. [PMID: 22902687 PMCID: PMC3493426 DOI: 10.4161/psb.21620] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The size of seeds and organs is coordinately determined by cell proliferation and cell expansion, but the mechanisms that set final seed and organ size are largely unknown in plants. In a recent study, we have demonstrated that the plant specific G protein γ subunit (AGG3) promotes seed and organ growth by increasing the period of proliferative growth in Arabidopsis. AGG3 is localized in plasma membrane and interacts with the G protein β subunit (AGB1). Homologs of AGG3 in rice (GS3 and DEP1/qPE9-1) have been identified as important quantitative trait loci for seed size and yield. However, rice GS3 and DEP1 influence seed and organ growth by restricting cell proliferation. Here, we discuss the possible molecular mechanisms by which Arabidopsis AGG3 and its rice homologs GS3 and DEP1 control seed and organ size.
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Li S, Liu Y, Zheng L, Chen L, Li N, Corke F, Lu Y, Fu X, Zhu Z, Bevan MW, Li Y. The plant-specific G protein γ subunit AGG3 influences organ size and shape in Arabidopsis thaliana. THE NEW PHYTOLOGIST 2012; 194:690-703. [PMID: 22380792 DOI: 10.1111/j.1469-8137.2012.04083.x] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
• Control of organ size and shape by cell proliferation and cell expansion is a fundamental developmental process, but the mechanisms that set the size and shape of determinate organs are largely unknown in plants. • Molecular, genetic, cytological and biochemical approaches were used to characterize the roles of the Arabidopsis thaliana G protein γ subunit (AGG3) gene in organ growth. • Here, we describe A. thaliana AGG3, which promotes petal growth by increasing the period of cell proliferation. Both the N-terminal region and the C-terminal domains of AGG3 are necessary for the function of AGG3. By contrast, analysis of a series of AGG3 derivatives with deletions in specific domains showed that the deletion of any of these domains cannot completely abolish the function of AGG3. The GFP-AGG3 fusion protein is localized to the plasma membrane. The predicted transmembrane domain plays an important role in the plasma membrane localization of AGG3. Genetic analyses revealed that AGG3 action requires a functional G protein α subunit (GPA1) and G protein β subunit (AGB1). • Our findings demonstrate that AGG3, GPA1 and AGB1 act in the same genetic pathway to influence organ size and shape in A. thaliana.
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Affiliation(s)
- Shengjun Li
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- Graduate School, Chinese Academy of Sciences, Beijing 100039, China
| | - Yaju Liu
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Leiying Zheng
- Centre of Bioenergy, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Liangliang Chen
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- Graduate School, Chinese Academy of Sciences, Beijing 100039, China
| | - Na Li
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Fiona Corke
- Department of Cell and Developmental Biology, John Innes Centre, Norwich NR4 7UH, UK
| | - Yaru Lu
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- College of Biological Sciences, Hebei Normal University, Shijiazhuang, China
| | - Xiangdong Fu
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Zhengge Zhu
- College of Biological Sciences, Hebei Normal University, Shijiazhuang, China
| | - Michael W Bevan
- Department of Cell and Developmental Biology, John Innes Centre, Norwich NR4 7UH, UK
| | - Yunhai Li
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
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Chakravorty D, Trusov Y, Zhang W, Acharya BR, Sheahan MB, McCurdy DW, Assmann SM, Botella JR. An atypical heterotrimeric G-protein γ-subunit is involved in guard cell K⁺-channel regulation and morphological development in Arabidopsis thaliana. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2011; 67:840-51. [PMID: 21575088 DOI: 10.1111/j.1365-313x.2011.04638.x] [Citation(s) in RCA: 154] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Currently, there are strong inconsistencies in our knowledge of plant heterotrimeric G-proteins that suggest the existence of additional members of the family. We have identified a new Arabidopsis G-protein γ-subunit (AGG3) that modulates morphological development and ABA-regulation of stomatal aperture. AGG3 strongly interacts with the Arabidopsis G-protein β-subunit in vivo and in vitro. Most importantly, AGG3-deficient mutants account for all but one of the 'orphan' phenotypes previously unexplained by the two known γ-subunits in Arabidopsis. AGG3 has unique characteristics never before observed in plant or animal systems, such as its size (more than twice that of canonical γ-subunits) and the presence of a C-terminal Cys-rich domain. AGG3 thus represent a novel class of G-protein γ-subunits, widely spread throughout the plant kingdom but not present in animals. Homologues of AGG3 in rice have been identified as important quantitative trait loci for grain size and yield, but due to the atypical nature of the proteins their identity as G-protein subunits was thus far unknown. Our work demonstrates a similar trend in seeds of Arabidopsis agg3 mutants, and implicates G-proteins in such a crucial agronomic trait. The discovery of this highly atypical subunit reinforces the emerging notion that plant and animal G-proteins have distinct as well as shared evolutionary pathways.
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Affiliation(s)
- David Chakravorty
- Plant Genetic Engineering Laboratory, School of Agriculture and Food Sciences, University of Queensland, Brisbane, Qld 4072, Australia
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Choudhury SR, Bisht NC, Thompson R, Todorov O, Pandey S. Conventional and novel Gγ protein families constitute the heterotrimeric G-protein signaling network in soybean. PLoS One 2011; 6:e23361. [PMID: 21853116 PMCID: PMC3154445 DOI: 10.1371/journal.pone.0023361] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2011] [Accepted: 07/13/2011] [Indexed: 12/22/2022] Open
Abstract
Heterotrimeric G-proteins comprised of Gα, Gβ and Gγ proteins are important signal transducers in all eukaryotes. The Gγ protein of the G-protein heterotrimer is crucial for its proper targeting at the plasma membrane and correct functioning. Gγ proteins are significantly smaller and more diverse than the Gα and Gβ proteins. In model plants Arabidopsis and rice that have a single Gα and Gβ protein, the presence of two canonical Gγ proteins provide some diversity to the possible heterotrimeric combinations. Our recent analysis of the latest version of the soybean genome has identified ten Gγ proteins which belong to three distinct families based on their C-termini. We amplified the full length cDNAs, analyzed their detailed expression profile by quantitative PCR, assessed their localization and performed yeast-based interaction analysis to evaluate interaction specificity with different Gβ proteins. Our results show that ten Gγ genes are retained in the soybean genome and have interesting expression profiles across different developmental stages. Six of the newly identified proteins belong to two plant-specific Gγ protein families. Yeast-based interaction analyses predict some degree of interaction specificity between different Gβ and Gγ proteins. This research thus identifies a highly diverse G-protein network from a plant species. Homologs of these novel proteins have been previously identified as QTLs for grain size and yield in rice.
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Affiliation(s)
- Swarup Roy Choudhury
- Donald Danforth Plant Science Center, St. Louis, Missouri, United States of America
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Sorek N, Gutman O, Bar E, Abu-Abied M, Feng X, Running MP, Lewinsohn E, Ori N, Sadot E, Henis YI, Yalovsky S. Differential effects of prenylation and s-acylation on type I and II ROPS membrane interaction and function. PLANT PHYSIOLOGY 2011; 155:706-20. [PMID: 21139084 PMCID: PMC3032461 DOI: 10.1104/pp.110.166850] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2010] [Accepted: 11/30/2010] [Indexed: 05/21/2023]
Abstract
Prenylation primarily by geranylgeranylation is required for membrane attachment and function of type I Rho of Plants (ROPs) and Gγ proteins, while type II ROPs are attached to the plasma membrane by S-acylation. Yet, it is not known how prenylation affects ROP membrane interaction dynamics and what are the functional redundancy and specificity of type I and type II ROPs. Here, we have used the expression of ROPs in mammalian cells together with geranylgeranylation and CaaX prenylation-deficient mutants to answer these questions. Our results show that the mechanism of type II ROP S-acylation and membrane attachment is unique to plants and likely responsible for the viability of plants in the absence of CaaX prenylation activity. The prenylation of ROPs determines their steady-state distribution between the plasma membrane and the cytosol but has little effect on membrane interaction dynamics. In addition, the prenyl group type has only minor effects on ROP function. Phenotypic analysis of the CaaX prenylation-deficient pluripetala mutant epidermal cells revealed that type I ROPs affect cell structure primarily on the adaxial side, while type II ROPs are functional and induce a novel cell division phenotype in this genetic background. Taken together, our studies show how prenyl and S-acyl lipid modifications affect ROP subcellular distribution, membrane interaction dynamics, and function.
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Chen H, Xiong L. myo-Inositol-1-phosphate synthase is required for polar auxin transport and organ development. J Biol Chem 2010; 285:24238-47. [PMID: 20516080 DOI: 10.1074/jbc.m110.123661] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
myo-Inositol-1-phosphate synthase is a conserved enzyme that catalyzes the first committed and rate-limiting step in inositol biosynthesis. Despite its wide occurrence in all eukaryotes, the role of myo-inositol-1-phosphate synthase and de novo inositol biosynthesis in cell signaling and organism development has been unclear. In this study, we isolated loss-of-function mutants in the Arabidopsis MIPS1 gene from different ecotypes. It was found that all null mips1 mutants are defective in embryogenesis, cotyledon venation patterning, root growth, and root cap development. The mutant roots are also agravitropic and have reduced basipetal auxin transport. mips1 mutants have significantly reduced levels of major phosphatidylinositols and exhibit much slower rates of endocytosis. Treatment with brefeldin A induces slower PIN2 protein aggregation in mips1, indicating altered PIN2 trafficking. Our results demonstrate that MIPS1 is critical for maintaining phosphatidylinositol levels and affects pattern formation in plants likely through regulation of auxin distribution.
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Affiliation(s)
- Hao Chen
- Donald Danforth Plant Science Center, St. Louis, MO 63132, USA
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48
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Huizinga DH, Denton R, Koehler KG, Tomasello A, Wood L, Sen SE, Crowell DN. Farnesylcysteine lyase is involved in negative regulation of abscisic acid signaling in Arabidopsis. MOLECULAR PLANT 2010; 3:143-55. [PMID: 19969520 PMCID: PMC2807925 DOI: 10.1093/mp/ssp091] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2009] [Accepted: 09/22/2009] [Indexed: 05/21/2023]
Abstract
The Arabidopsis FCLY gene encodes a specific farnesylcysteine (FC) lyase, which is responsible for the oxidative metabolism of FC to farnesal and cysteine. In addition, fcly mutants with quantitative decreases in FC lyase activity exhibit an enhanced response to ABA. However, the enzymological properties of the FCLY-encoded enzyme and its precise role in ABA signaling remain unclear. Here, we show that recombinant Arabidopsis FC lyase expressed in insect cells exhibits high selectivity for FC as a substrate and requires FAD and molecular oxygen for activity. Arabidopsis FC lyase is also shown to undergo post-translational N-glycosylation. FC, which is a competitive inhibitor of isoprenylcysteine methyltransferase (ICMT), accumulates in fcly mutants. Moreover, the enhanced response of fcly mutants to ABA is reversed by ICMT overexpression. These observations support the hypothesis that the ABA hypersensitive phenotype of fcly plants is the result of FC accumulation and inhibition of ICMT.
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Affiliation(s)
- David H. Huizinga
- Department of Biology, Indiana University-Purdue University Indianapolis, 723 West Michigan Street, Indianapolis, IN 46202, USA
| | - Ryan Denton
- Department of Chemistry, Indiana University-Purdue University Indianapolis, 402 N. Blackford Street, Indianapolis, IN 46202, USA
| | - Kelly G. Koehler
- Department of Biology, Indiana University-Purdue University Indianapolis, 723 West Michigan Street, Indianapolis, IN 46202, USA
| | - Ashley Tomasello
- Department of Chemistry, The College of New Jersey, 2000 Pennington Road, Ewing, NJ 08628, USA
| | - Lyndsay Wood
- Department of Chemistry, The College of New Jersey, 2000 Pennington Road, Ewing, NJ 08628, USA
| | - Stephanie E. Sen
- Department of Chemistry, The College of New Jersey, 2000 Pennington Road, Ewing, NJ 08628, USA
| | - Dring N. Crowell
- Department of Biological Sciences, Idaho State University, 650 Memorial Drive, Pocatello, ID 83209, USA
- To whom correspondence should be addressed. E-mail , fax 208-282-4570, tel. 208-282-3171
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50
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Carland F, Nelson T. CVP2- and CVL1-mediated phosphoinositide signaling as a regulator of the ARF GAP SFC/VAN3 in establishment of foliar vein patterns. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2009; 59:895-907. [PMID: 19473324 DOI: 10.1111/j.1365-313x.2009.03920.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
In foliar organs of dicots, veins are arranged in a highly branched or reticulated pattern for efficient distribution of water, photosynthates and signaling molecules. Recent evidence suggests that the patterns rely in part on regulation of intracellular vesicle transport and cell polarity in selected cells during leaf development. The sorting of vesicle cargos to discrete cellular sites is regulated in yeast and animal cells by the binding of specific phosphoinositides (PIs). We report here that, in the plant Arabidopsis, specific PIs guide the vesicle traffic that is essential for polarized and continuous vein pattern formation. Mutations in SFC/VAN3, an ADP-ribosylation factor GTPase-activating protein (ARF GAP) with a PI-binding pleckstrin homology domain, result in discontinuous vein patterns. Plants with mutations in both CVP2 and CVL1, which encode inositol polyphosphate 5'-phosphatases that generate the specific PI ligand for the pleckstrin homology domain of SFC/VAN3, phosphatidylinositol-4-monophosphate (PI(4)P), have a discontinuous vein phenotype identical to that of sfc/van3 mutants. Single cvp2 or cvl1 mutants show weak and no discontinuous vein phenotypes, respectively, suggesting that they act redundantly. We propose that these two 5'-phosphatases regulate vein continuity and cell polarity by generating a specific PI ligand for SFC/VAN3.
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Affiliation(s)
- Francine Carland
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT 06520, USA
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