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Xu D, Tang W, Ma Y, Wang X, Yang Y, Wang X, Xie L, Huang S, Qin T, Tang W, Xu Z, Li L, Tang Y, Chen M, Ma Y. Arabidopsis G-protein β subunit AGB1 represses abscisic acid signaling via attenuation of the MPK3-VIP1 phosphorylation cascade. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:1615-1632. [PMID: 37988280 DOI: 10.1093/jxb/erad464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Accepted: 11/20/2023] [Indexed: 11/23/2023]
Abstract
Heterotrimeric G proteins play key roles in cellular processes. Although phenotypic analyses of Arabidopsis Gβ (AGB1) mutants have implicated G proteins in abscisic acid (ABA) signaling, the AGB1-mediated modules involved in ABA responses remain unclear. We found that a partial AGB1 protein was localized to the nucleus where it interacted with ABA-activated VirE2-interacting protein 1 (VIP1) and mitogen-activated protein kinase 3 (MPK3). AGB1 acts as an upstream negative regulator of VIP1 activity by initiating responses to ABA and drought stress, and VIP1 regulates the ABA signaling pathway in an MPK3-dependent manner in Arabidopsis. AGB1 outcompeted VIP1 for interaction with the C-terminus of MPK3, and prevented phosphorylation of VIP1 by MPK3. Importantly, ABA treatment reduced AGB1 expression in the wild type, but increased in vip1 and mpk3 mutants. VIP1 associates with ABA response elements present in the AGB1 promoter, forming a negative feedback regulatory loop. Thus, our study defines a new mechanism for fine-tuning ABA signaling through the interplay between AGB1 and MPK3-VIP1. Furthermore, it suggests a common G protein mechanism to receive and transduce signals from the external environment.
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Affiliation(s)
- Dongbei Xu
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences (CAAS)/National Key Facility for Crop Gene Resources and Genetic Improvement, Key Laboratory of Biology and Genetic Improvement of Triticeae Crops, Ministry of Agriculture, Beijing 100081, China
- College of Agronomy, Sichuan Agricultural University, Chengdu 611130, China
| | - Wensi Tang
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences (CAAS)/National Key Facility for Crop Gene Resources and Genetic Improvement, Key Laboratory of Biology and Genetic Improvement of Triticeae Crops, Ministry of Agriculture, Beijing 100081, China
| | - Yanan Ma
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences (CAAS)/National Key Facility for Crop Gene Resources and Genetic Improvement, Key Laboratory of Biology and Genetic Improvement of Triticeae Crops, Ministry of Agriculture, Beijing 100081, China
| | - Xia Wang
- College of Agronomy, Sichuan Agricultural University, Chengdu 611130, China
| | - Yanzhi Yang
- State Key Laboratory of Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences, School of Life Sciences, Peking University, Beijing 100871, China
| | - Xiaoting Wang
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences (CAAS)/National Key Facility for Crop Gene Resources and Genetic Improvement, Key Laboratory of Biology and Genetic Improvement of Triticeae Crops, Ministry of Agriculture, Beijing 100081, China
| | - Lina Xie
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences (CAAS)/National Key Facility for Crop Gene Resources and Genetic Improvement, Key Laboratory of Biology and Genetic Improvement of Triticeae Crops, Ministry of Agriculture, Beijing 100081, China
| | - Suo Huang
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences (CAAS)/National Key Facility for Crop Gene Resources and Genetic Improvement, Key Laboratory of Biology and Genetic Improvement of Triticeae Crops, Ministry of Agriculture, Beijing 100081, China
| | - Tengfei Qin
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences (CAAS)/National Key Facility for Crop Gene Resources and Genetic Improvement, Key Laboratory of Biology and Genetic Improvement of Triticeae Crops, Ministry of Agriculture, Beijing 100081, China
| | - Weilin Tang
- College of Agronomy, Sichuan Agricultural University, Chengdu 611130, China
| | - Zhaoshi Xu
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences (CAAS)/National Key Facility for Crop Gene Resources and Genetic Improvement, Key Laboratory of Biology and Genetic Improvement of Triticeae Crops, Ministry of Agriculture, Beijing 100081, China
| | - Lei Li
- State Key Laboratory of Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences, School of Life Sciences, Peking University, Beijing 100871, China
| | - Yimiao Tang
- Institute of Hybrid Wheat, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China
| | - Ming Chen
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences (CAAS)/National Key Facility for Crop Gene Resources and Genetic Improvement, Key Laboratory of Biology and Genetic Improvement of Triticeae Crops, Ministry of Agriculture, Beijing 100081, China
| | - Youzhi Ma
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences (CAAS)/National Key Facility for Crop Gene Resources and Genetic Improvement, Key Laboratory of Biology and Genetic Improvement of Triticeae Crops, Ministry of Agriculture, Beijing 100081, China
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Lai L, Ruan J, Xiao C, Yi P. The putative myristoylome of Physcomitrium patens reveals conserved features of myristoylation in basal land plants. PLANT CELL REPORTS 2023; 42:1107-1124. [PMID: 37052714 DOI: 10.1007/s00299-023-03016-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 04/03/2023] [Indexed: 05/12/2023]
Abstract
KEYMESSAGE The putative myristoylome of moss P. patens opens an avenue for studying myristoylation substrates in non-canonical model plants. A myristoylation signal was shown sufficient for membrane targeting and useful for membrane dynamics visualization during cell growth. N-myristoylation (MYR) is one form of lipid modification catalyzed by N-myristoyltransferase that enables protein-membrane association. MYR is highly conserved in all eukaryotes. However, the study of MYR is limited to a few models such as yeasts, humans, and Arabidopsis. Here, using prediction tools, we report the characterization of the putative myristoylome of the moss Physcomitrium patens. We show that basal land plants display a similar signature of MYR to Arabidopsis and may have organism-specific substrates. Phylogenetically, MYR signals have mostly co-evolved with protein function but also exhibit variability in an organism-specific manner. We also demonstrate that the MYR motif of a moss brassinosteroid-signaling kinase is an efficient plasma membrane targeting signal and labels lipid-rich domains in tip-growing cells. Our results provide insights into the myristoylome in a basal land plant and lay the foundation for future studies on MYR and its roles in plant evolution.
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Affiliation(s)
- Linyu Lai
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, No. 24 South Section 1, Yihuan Road, Wuhou District, Chengdu, Sichuan, 610064, People's Republic of China
| | - Jingtong Ruan
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, No. 24 South Section 1, Yihuan Road, Wuhou District, Chengdu, Sichuan, 610064, People's Republic of China
| | - Chaowen Xiao
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, No. 24 South Section 1, Yihuan Road, Wuhou District, Chengdu, Sichuan, 610064, People's Republic of China
| | - Peishan Yi
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, No. 24 South Section 1, Yihuan Road, Wuhou District, Chengdu, Sichuan, 610064, People's Republic of China.
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Li M, Feng F, Feng H, Hu P, Xue Y, Xu T, Song E. VAMP4 regulates insulin levels by targeting secretory granules to lysosomes. J Cell Biol 2022; 221:213439. [PMID: 36053215 PMCID: PMC9441717 DOI: 10.1083/jcb.202110164] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 06/28/2022] [Accepted: 07/25/2022] [Indexed: 11/22/2022] Open
Abstract
Insulin levels are essential for the maintenance of glucose homeostasis, and deviations lead to pathoglycemia or diabetes. However, the metabolic mechanism controlling insulin quantity and quality is poorly understood. In pancreatic β cells, insulin homeostasis and release are tightly governed by insulin secretory granule (ISG) trafficking, but the required regulators and mechanisms are largely unknown. Here, we identified that VAMP4 controlled the insulin levels in response to glucose challenge. VAMP4 deficiency led to increased blood insulin levels and hyperresponsiveness to glucose. In β cells, VAMP4 is packaged into immature ISGs (iISGs) at trans-Golgi networks and subsequently resorted to clathrin-coated vesicles during granule maturation. VAMP4-positive iISGs and resorted vesicles then fuse with lysosomes facilitated by a SNARE complex consisting of VAMP4, STX7, STX8, and VTI1B, which ensures the breakdown of excess (pro)insulin and obsolete materials and thus maintenance of intracellular insulin homeostasis. Thus, VAMP4 is a key factor regulating the insulin levels and a potential target for the treatment of diabetes.
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Affiliation(s)
- Min Li
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China,Guangzhou Laboratory, Guangzhou, China,Bioland Laboratory (Guangzhou Regenerative Medicine and Health Guangdong Laboratory), Guangzhou, China,Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Fengping Feng
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Han Feng
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Pengkai Hu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Yanhong Xue
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Tao Xu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China,Guangzhou Laboratory, Guangzhou, China,Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China,Dr. Tao Xu:
| | - Eli Song
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China,Correspondence to Dr. Eli Song:
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RNA-Binding Protein MAC5A Is Required for Gibberellin-Regulated Stamen Development. Int J Mol Sci 2022; 23:ijms23042009. [PMID: 35216125 PMCID: PMC8874600 DOI: 10.3390/ijms23042009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 02/09/2022] [Accepted: 02/09/2022] [Indexed: 11/23/2022] Open
Abstract
The development of floral organs is coordinated by an elaborate network of homeotic genes, and gibberellin (GA) signaling is involved in floral organ development; however, the underlying molecular mechanisms remain elusive. In the present study, we found that MOS4-ASSOCIATED COMPLEX 5A (MAC5A), which is a protein containing an RNA-binding motif, was involved in the development of sepals, petals, and stamens; either the loss or gain of MAC5A function resulted in stamen malformation and a reduced seed set. The exogenous application of GA considerably exacerbated the defects in mac5a null mutants, including fewer stamens and male sterility. MAC5A was predominantly expressed in pollen grains and stamens, and overexpression of MAC5A affected the expression of homeotic genes such as APETALA1 (AP1), AP2, and AGAMOUS (AG). MAC5A may interact with RABBIT EARS (RBE), a repressor of AG expression in Arabidopsis flowers. The petal defect in rbe null mutants was at least partly rescued in mac5a rbe double mutants. These findings suggest that MAC5A is a novel factor that is required for the normal development of stamens and depends on the GA signaling pathway.
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Xu W, Wu D, Yang T, Sun C, Wang Z, Han B, Wu S, Yu A, Chapman MA, Muraguri S, Tan Q, Wang W, Bao Z, Liu A, Li DZ. Genomic insights into the origin, domestication and genetic basis of agronomic traits of castor bean. Genome Biol 2021; 22:113. [PMID: 33874982 PMCID: PMC8056531 DOI: 10.1186/s13059-021-02333-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 03/29/2021] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Castor bean (Ricinus communis L.) is an important oil crop, which belongs to the Euphorbiaceae family. The seed oil of castor bean is currently the only commercial source of ricinoleic acid that can be used for producing about 2000 industrial products. However, it remains largely unknown regarding the origin, domestication, and the genetic basis of key traits of castor bean. RESULTS Here we perform a de novo chromosome-level genome assembly of the wild progenitor of castor bean. By resequencing and analyzing 505 worldwide accessions, we reveal that the accessions from East Africa are the extant wild progenitors of castor bean, and the domestication occurs ~ 3200 years ago. We demonstrate that significant genetic differentiation between wild populations in Kenya and Ethiopia is associated with past climate fluctuation in the Turkana depression ~ 7000 years ago. This dramatic change in climate may have caused the genetic bottleneck in wild castor bean populations. By a genome-wide association study, combined with quantitative trait locus analysis, we identify important candidate genes associated with plant architecture and seed size. CONCLUSIONS This study provides novel insights of domestication and genome evolution of castor bean, which facilitates genomics-based breeding of this important oilseed crop and potentially other tree-like crops in future.
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Affiliation(s)
- Wei Xu
- Department of Economic Plants and Biotechnology, Yunnan Key Laboratory for Wild Plant Resources, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
| | - Di Wu
- Department of Economic Plants and Biotechnology, Yunnan Key Laboratory for Wild Plant Resources, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
| | - Tianquan Yang
- Department of Economic Plants and Biotechnology, Yunnan Key Laboratory for Wild Plant Resources, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
| | - Chao Sun
- Department of Economic Plants and Biotechnology, Yunnan Key Laboratory for Wild Plant Resources, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
| | - Zaiqing Wang
- Department of Economic Plants and Biotechnology, Yunnan Key Laboratory for Wild Plant Resources, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
| | - Bing Han
- Department of Economic Plants and Biotechnology, Yunnan Key Laboratory for Wild Plant Resources, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
| | - Shibo Wu
- Department of Economic Plants and Biotechnology, Yunnan Key Laboratory for Wild Plant Resources, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
| | - Anmin Yu
- Key Laboratory for Forest Resource Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Southwest Forestry University, Kunming, 650224, China
| | - Mark A Chapman
- Biological Sciences and Centre for Underutilised Crops, University of Southampton, Southampton, SO17 1BJ, UK
| | - Sammy Muraguri
- Department of Economic Plants and Biotechnology, Yunnan Key Laboratory for Wild Plant Resources, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
| | - Qing Tan
- Department of Economic Plants and Biotechnology, Yunnan Key Laboratory for Wild Plant Resources, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
| | - Wenbo Wang
- Department of Economic Plants and Biotechnology, Yunnan Key Laboratory for Wild Plant Resources, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
| | - Zhigui Bao
- Shanghai OE Biotech Co., Ltd, Shanghai, 201114, China
| | - Aizhong Liu
- Key Laboratory for Forest Resource Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Southwest Forestry University, Kunming, 650224, China.
| | - De-Zhu Li
- Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China.
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Rasul F, Gupta S, Olas JJ, Gechev T, Sujeeth N, Mueller-Roeber B. Priming with a Seaweed Extract Strongly Improves Drought Tolerance in Arabidopsis. Int J Mol Sci 2021; 22:1469. [PMID: 33540571 PMCID: PMC7867171 DOI: 10.3390/ijms22031469] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Revised: 01/26/2021] [Accepted: 01/27/2021] [Indexed: 02/07/2023] Open
Abstract
Drought represents a major threat to plants in natural ecosystems and agricultural settings. The biostimulant Super Fifty (SF), produced from the brown alga Ascophyllum nodosum, enables ecologically friendly stress mitigation. We investigated the physiological and whole-genome transcriptome responses of Arabidopsis thaliana to drought stress after a treatment with SF. SF strongly decreased drought-induced damage. Accumulation of reactive oxygen species (ROS), which typically stifle plant growth during drought, was reduced in SF-primed plants. Relative water content remained high in SF-treated plants, whilst ion leakage, a measure of cell damage, was reduced compared to controls. Plant growth requires a functional shoot apical meristem (SAM). Expression of a stress-responsive negative growth regulator, RESPONSIVE TO DESICCATION 26 (RD26), was repressed by SF treatment at the SAM, consistent with the model that SF priming maintains the function of the SAM during drought stress. Accordingly, expression of the cell cycle marker gene HISTONE H4 (HIS4) was maintained at the SAMs of SF-primed plants, revealing active cell cycle progression after SF priming during drought. In accordance with this, CYCP2;1, which promotes meristem cell division, was repressed by drought but enhanced by SF. SF also positively affected stomatal behavior to support the tolerance to drought stress. Collectively, our data show that SF priming mitigates multiple cellular processes that otherwise impair plant growth under drought stress, thereby providing a knowledge basis for future research on crops.
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Affiliation(s)
- Fiaz Rasul
- Institute of Biochemistry and Biology, University of Potsdam, Karl Liebknecht Str. 24-25, 14476 Potsdam-Golm, Germany; (F.R.); (S.G.); (J.J.O.)
- BioAtlantis Ltd., Clash Industrial Estate, V92 RWV5 Tralee, Ireland
| | - Saurabh Gupta
- Institute of Biochemistry and Biology, University of Potsdam, Karl Liebknecht Str. 24-25, 14476 Potsdam-Golm, Germany; (F.R.); (S.G.); (J.J.O.)
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany
| | - Justyna Jadwiga Olas
- Institute of Biochemistry and Biology, University of Potsdam, Karl Liebknecht Str. 24-25, 14476 Potsdam-Golm, Germany; (F.R.); (S.G.); (J.J.O.)
| | - Tsanko Gechev
- Center of Plant Systems Biology and Biotechnology (CPSBB), 139 Ruski Blvd., 4000 Plovdiv, Bulgaria;
- Department of Plant Physiology and Molecular Biology, University of Plovdiv, 24 Tsar Assen Str., 4000 Plovdiv, Bulgaria
| | | | - Bernd Mueller-Roeber
- Institute of Biochemistry and Biology, University of Potsdam, Karl Liebknecht Str. 24-25, 14476 Potsdam-Golm, Germany; (F.R.); (S.G.); (J.J.O.)
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany
- Center of Plant Systems Biology and Biotechnology (CPSBB), 139 Ruski Blvd., 4000 Plovdiv, Bulgaria;
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Tsugama D, Yoon HS, Fujino K, Liu S, Takano T. Protein phosphatase 2A regulates the nuclear accumulation of the Arabidopsis bZIP protein VIP1 under hypo-osmotic stress. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:6101-6112. [PMID: 31504762 PMCID: PMC6859724 DOI: 10.1093/jxb/erz384] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 08/16/2019] [Indexed: 05/21/2023]
Abstract
VIP1 is a bZIP transcription factor in Arabidopsis thaliana. When cells are exposed to mechanical stress, VIP1 transiently accumulates in the nucleus, where it regulates the expression of its target genes and suppresses mechanical stress-induced root waving. The nuclear-cytoplasmic shuttling of VIP1 is regulated by phosphorylation and calcium-dependent signaling, but specific regulators of these processes remain to be identified. Here, inhibitors of protein phosphatase 2A (PP2A) are shown to inhibit both the mechanical stress-induced dephosphorylation and nuclear accumulation of VIP1. The PP2A B subunit, which recruits substrates of PP2A holoenzyme, is classified into B, B', B'', and B''' families. Using bimolecular fluorescence complementation, in vitro pull-down, and yeast two-hybrid assays, we show that VIP1 interacts with at least two of the six members of the Arabidopsis PP2A B''-family subunit, which have calcium-binding EF-hand motifs. VIP1AAA, a constitutively nuclear-localized VIP1 variant with substitutions in putative phosphorylation sites of VIP1, suppressed the root waving induced by VIP1-SRDX (a repression domain-fused variant of VIP1). These results support the idea that VIP1 is dephosphorylated by PP2A and that the dephosphorylation suppresses the root waving. The phosphorylation sites of VIP1 and its homologs were narrowed down by in vitro phosphorylation, yeast two-hybrid, and protein subcellular localization assays.
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Affiliation(s)
- Daisuke Tsugama
- Asian Natural Environmental Science Center (ANESC), The University of Tokyo, Midori-cho, Nishitokyo-shi, Tokyo, Japan
- Laboratory of Crop Physiology, Research Faculty of Agriculture, Hokkaido University, Kita 9 Nishi 9 Kita-ku, Sapporo-shi, Hokkaido, Japan
- Correspondence:
| | - Hyuk Sung Yoon
- Asian Natural Environmental Science Center (ANESC), The University of Tokyo, Midori-cho, Nishitokyo-shi, Tokyo, Japan
- Laboratory of Crop Physiology, Research Faculty of Agriculture, Hokkaido University, Kita 9 Nishi 9 Kita-ku, Sapporo-shi, Hokkaido, Japan
| | - Kaien Fujino
- Laboratory of Crop Physiology, Research Faculty of Agriculture, Hokkaido University, Kita 9 Nishi 9 Kita-ku, Sapporo-shi, Hokkaido, Japan
| | - Shenkui Liu
- State Key Laboratory of Subtropical Silviculture, Zhejiang A & F University, Lin’an, Hangzhou, PR China
| | - Tetsuo Takano
- Asian Natural Environmental Science Center (ANESC), The University of Tokyo, Midori-cho, Nishitokyo-shi, Tokyo, Japan
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Bhaskara GB, Wong MM, Verslues PE. The flip side of phospho-signalling: Regulation of protein dephosphorylation and the protein phosphatase 2Cs. PLANT, CELL & ENVIRONMENT 2019; 42:2913-2930. [PMID: 31314921 DOI: 10.1111/pce.13616] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 06/21/2019] [Accepted: 06/29/2019] [Indexed: 05/12/2023]
Abstract
Protein phosphorylation is a key signalling mechanism and has myriad effects on protein function. Phosphorylation by protein kinases can be reversed by protein phosphatases, thus allowing dynamic control of protein phosphorylation. Although this may suggest a straightforward kinase-phosphatase relationship, plant genomes contain five times more kinases than phosphatases. Here, we examine phospho-signalling from a protein phosphatase centred perspective and ask how relatively few phosphatases regulate many phosphorylation sites. The most abundant class of plant phosphatases, the protein phosphatase 2Cs (PP2Cs), is surrounded by a web of regulation including inhibitor and activator proteins as well as posttranslational modifications that regulate phosphatase activity, control phosphatase stability, or determine the subcellular locations where the phosphatase is present and active. These mechanisms are best established for the Clade A PP2Cs, which are key components of stress and abscisic acid signalling. We also describe other PP2C clades and illustrate how these phosphatases are highly regulated and involved in a wide range of physiological functions. Together, these examples of multiple layers of phosphatase regulation help explain the unbalanced kinase-phosphatase ratio. Continued use of phosphoproteomics to examine phosphatase targets and phosphatase-kinase relationships will be important for deeper understanding of phosphoproteome regulation.
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Affiliation(s)
| | - Min May Wong
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Paul E Verslues
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, 11529, Taiwan
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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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10
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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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11
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Ono S, Liu H, Tsuda K, Fukai E, Tanaka K, Sasaki T, Nonomura KI. EAT1 transcription factor, a non-cell-autonomous regulator of pollen production, activates meiotic small RNA biogenesis in rice anther tapetum. PLoS Genet 2018; 14:e1007238. [PMID: 29432414 PMCID: PMC5825165 DOI: 10.1371/journal.pgen.1007238] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 02/23/2018] [Accepted: 02/01/2018] [Indexed: 11/18/2022] Open
Abstract
The 24-nucleotides (nt) phased secondary small interfering RNA (phasiRNA) is a unique class of plant small RNAs abundantly expressed in monocot anthers at early meiosis. Previously, 44 intergenic regions were identified as the loci for longer precursor RNAs of 24-nt phasiRNAs (24-PHASs) in the rice genome. However, the regulatory mechanism that determines spatiotemporal expression of these RNAs has remained elusive. ETERNAL TAPETUM1 (EAT1) is a basic-helix-loop-helix (bHLH) transcription factor indispensable for induction of programmed cell death (PCD) in postmeiotic anther tapetum, the somatic nursery for pollen production. In this study, EAT1-dependent non-cell-autonomous regulation of male meiosis was evidenced from microscopic observation of the eat1 mutant, in which meiosis with aberrantly decondensed chromosomes was retarded but accomplished somehow, eventually resulting in abortive microspores due to an aberrant tapetal PCD. EAT1 protein accumulated in tapetal-cell nuclei at early meiosis and postmeiotic microspore stages. Meiotic EAT1 promoted transcription of 24-PHAS RNAs at 101 loci, and importantly, also activated DICER-LIKE5 (DCL5, previous DCL3b in rice) mRNA transcription that is required for processing of double-stranded 24-PHASs into 24-nt lengths. From the results of the chromatin-immunoprecipitation and transient expression analyses, another tapetum-expressing bHLH protein, TDR INTERACTING PROTEIN2 (TIP2), was suggested to be involved in meiotic small-RNA biogenesis. The transient assay also demonstrated that UNDEVELOPED TAPETUM1 (UDT1)/bHLH164 is a potential interacting partner of both EAT1 and TIP2 during early meiosis. This study indicates that EAT1 is one of key regulators triggering meiotic phasiRNA biogenesis in anther tapetum, and that other bHLH proteins, TIP2 and UDT1, also play some important roles in this process. Spatiotemporal expression control of these bHLH proteins is a clue to orchestrate precise meiosis progression and subsequent pollen production non-cell-autonomously.
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Affiliation(s)
- Seijiro Ono
- Experimental Farm, National Institute of Genetics, Yata, Mishima, Shizuoka, Japan
| | - Hua Liu
- Experimental Farm, National Institute of Genetics, Yata, Mishima, Shizuoka, Japan
| | - Katsutoshi Tsuda
- Experimental Farm, National Institute of Genetics, Yata, Mishima, Shizuoka, Japan
- Department of Genetics, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Yata, Mishima, Shizuoka, Japan
| | - Eigo Fukai
- Graduate School of Science and Technology, Niigata University, Ikarashi, Nishi-ku, Niigata, Japan
| | - Keisuke Tanaka
- NODAI Genome Research Center, Tokyo University of Agriculture, Sakuragaoka, Setagaya-ku, Tokyo, Japan
| | - Takuji Sasaki
- NODAI Research Institute, Tokyo University of Agriculture, Sakuragaoka, Setagaya-ku, Tokyo, Japan
| | - Ken-Ichi Nonomura
- Experimental Farm, National Institute of Genetics, Yata, Mishima, Shizuoka, Japan
- Department of Genetics, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Yata, Mishima, Shizuoka, Japan
- * E-mail:
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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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Xu DB, Chen M, Ma YN, Xu ZS, Li LC, Chen YF, Ma YZ. A G-protein β subunit, AGB1, negatively regulates the ABA response and drought tolerance by down-regulating AtMPK6-related pathway in Arabidopsis. PLoS One 2015; 10:e0116385. [PMID: 25635681 PMCID: PMC4312036 DOI: 10.1371/journal.pone.0116385] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Accepted: 12/05/2014] [Indexed: 01/08/2023] Open
Abstract
Heterotrimeric G-proteins are versatile regulators involved in diverse cellular processes in eukaryotes. In plants, the function of G-proteins is primarily associated with ABA signaling. However, the downstream effectors and the molecular mechanisms in the ABA pathway remain largely unknown. In this study, an AGB1 mutant (agb1-2) was found to show enhanced drought tolerance, indicating that AGB1 might negatively regulate drought tolerance in Arabidopsis. Data showed that AGB1 interacted with protein kinase AtMPK6 that was previously shown to phosphorylate AtVIP1, a transcription factor responding to ABA signaling. Our study found that transcript levels of three ABA responsive genes, AtMPK6, AtVIP1 and AtMYB44 (downstream gene of AtVIP1), were significantly up-regulated in agb1-2 lines after ABA or drought treatments. Other ABA-responsive and drought-inducible genes, such as RD29A (downstream gene of AtMYB44), were also up-regulated in agb1-2 lines. Furthermore, overexpression of AtVIP1 resulted in hypersensitivity to ABA at seed germination and seedling stages, and significantly enhanced drought tolerance in transgenic plants. These results suggest that AGB1 was involved in the ABA signaling pathway and drought tolerance in Arabidopsis through down-regulating the AtMPK6, AtVIP1 and AtMYB44 cascade.
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Affiliation(s)
- Dong-bei Xu
- College of Agriculture, Northwest A&F University, Yangling, Shaanxi, 712100, China
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences (CAAS)/National Key Facility for Crop Gene Resources and Genetic Improvement, Key Laboratory of Biology and Genetic Improvement of Triticeae Crops, Ministry of Agriculture, Beijing, 100081, China
| | - Ming Chen
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences (CAAS)/National Key Facility for Crop Gene Resources and Genetic Improvement, Key Laboratory of Biology and Genetic Improvement of Triticeae Crops, Ministry of Agriculture, Beijing, 100081, China
| | - Ya-nan Ma
- College of Agriculture, Northwest A&F University, Yangling, Shaanxi, 712100, China
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences (CAAS)/National Key Facility for Crop Gene Resources and Genetic Improvement, Key Laboratory of Biology and Genetic Improvement of Triticeae Crops, Ministry of Agriculture, Beijing, 100081, China
| | - Zhao-shi Xu
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences (CAAS)/National Key Facility for Crop Gene Resources and Genetic Improvement, Key Laboratory of Biology and Genetic Improvement of Triticeae Crops, Ministry of Agriculture, Beijing, 100081, China
| | - Lian-cheng Li
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences (CAAS)/National Key Facility for Crop Gene Resources and Genetic Improvement, Key Laboratory of Biology and Genetic Improvement of Triticeae Crops, Ministry of Agriculture, Beijing, 100081, China
| | - Yao-feng Chen
- College of Agriculture, Northwest A&F University, Yangling, Shaanxi, 712100, China
- * E-mail: (YC); (YZM)
| | - You-zhi Ma
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences (CAAS)/National Key Facility for Crop Gene Resources and Genetic Improvement, Key Laboratory of Biology and Genetic Improvement of Triticeae Crops, Ministry of Agriculture, Beijing, 100081, China
- * E-mail: (YC); (YZM)
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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: 51] [Impact Index Per Article: 5.1] [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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Abstract
Investigators studying G protein-coupled signaling--often called the best-understood pathway in the world owing to intense research in medical fields--have adopted plants as a new model to explore the plasticity and evolution of G signaling. Much research on plant G signaling has not disappointed. Although plant cells have most of the core elements found in animal G signaling, differences in network architecture and intrinsic properties of plant G protein elements make G signaling in plant cells distinct from the animal paradigm. In contrast to animal G proteins, plant G proteins are self-activating, and therefore regulation of G activation in plants occurs at the deactivation step. The self-activating property also means that plant G proteins do not need and therefore do not have typical animal G protein-coupled receptors. Targets of activated plant G proteins, also known as effectors, are unlike effectors in animal cells. The simpler repertoire of G signal elements in Arabidopsis makes G signaling easier to manipulate in a multicellular context.
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Affiliation(s)
- Daisuke Urano
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599
| | - Alan M. Jones
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599
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16
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Kansup J, Tsugama D, Liu S, Takano T. The Arabidopsis adaptor protein AP-3μ interacts with the G-protein β subunit AGB1 and is involved in abscisic acid regulation of germination and post-germination development. JOURNAL OF EXPERIMENTAL BOTANY 2013; 64:5611-21. [PMID: 24098050 PMCID: PMC3871816 DOI: 10.1093/jxb/ert327] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Heterotrimeric G-proteins (G-proteins) have been implicated in ubiquitous signalling mechanisms in eukaryotes. In plants, G-proteins modulate hormonal and stress responses and regulate diverse developmental processes. However, the molecular mechanisms of their functions are largely unknown. A yeast two-hybrid screen was performed to identify interacting partners of the Arabidopsis G-protein β subunit AGB1. One of the identified AGB1-interacting proteins is the Arabidopsis adaptor protein AP-3µ. The interaction between AGB1 and AP-3µ was confirmed by an in vitro pull-down assay and bimolecular fluorescence complementation assay. Two ap-3µ T-DNA insertional mutants were found to be hyposensitive to abscisic acid (ABA) during germination and post-germination growth, whereas agb1 mutants were hypersensitive to ABA. During seed germination, agb1/ap-3µ double mutants were more sensitive to ABA than the wild type but less sensitive than agb1 mutants. However, in post-germination growth, the double mutants were as sensitive to ABA as agb1 mutants. These data suggest that AP-3µ positively regulates the ABA responses independently of AGB1 in seed germination, while AP-3µ does require AGB1 to regulate ABA responses during post-germination growth.
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Affiliation(s)
- Jeeraporn Kansup
- Asian Natural Environmental Science Center, The University of Tokyo, Nishitokyo, Tokyo 188-0002, Japan
| | - Daisuke Tsugama
- Asian Natural Environmental Science Center, The University of Tokyo, Nishitokyo, Tokyo 188-0002, Japan
- Laboratory of Plant Molecular Genetics, Graduate School of Agricultural and Life Sciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113–8657, Japan
- * Present address: Biology Department, 208 Mueller Laboratory, Pennsylvania State University, University Park, PA 16802, USA
| | - Shenkui Liu
- Alkali Soil Natural Environmental Science Center, Northeast Forestry University, Harbin 150040, China
| | - Tetsuo Takano
- Asian Natural Environmental Science Center, The University of Tokyo, Nishitokyo, Tokyo 188-0002, Japan
- To whom correspondence should be addressed. E-mail:
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17
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Tsugama D, Liu S, Takano T. A bZIP protein, VIP1, interacts with Arabidopsis heterotrimeric G protein β subunit, AGB1. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2013; 71:240-6. [PMID: 23974356 DOI: 10.1016/j.plaphy.2013.07.024] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Accepted: 07/31/2013] [Indexed: 05/05/2023]
Abstract
Heterotrimeric G proteins (Gα, Gβ, Gγ) are signaling molecules conserved among eukaryotic species. The G proteins transmit signals via protein-protein interactions. By a yeast two-hybrid screen, we identified a bZIP protein, VIP1, as an Arabidopsis thaliana Gβ (AGB1)-interacting partner. The interaction between AGB1 and VIP1 was confirmed by an in vitro GST pull-down assay and a bimolecular fluorescence complementation (BiFC) assay. VIP1 was previously reported to be a regulator of osmosensory signaling. Interestingly, the BiFC pattern between AGB1 and VIP1 was speckled when cells were incubated in a hypotonic solution, but not when cells were incubated in a mannitol-containing hypertonic solution, suggesting that the subcellular localization of the AGB1-VIP1 complex is regulated by extracellular osmolarity and/or turgor pressure.
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Affiliation(s)
- Daisuke Tsugama
- Asian Natural Environmental Science Center (ANESC), The University of Tokyo, 1-1-1 Midori-cho, Nishitokyo-shi, Tokyo, 188-0002, Japan
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18
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Tsugama D, Liu S, Takano T. Arabidopsis heterotrimeric G protein β subunit, AGB1, regulates brassinosteroid signalling independently of BZR1. JOURNAL OF EXPERIMENTAL BOTANY 2013; 64:3213-23. [PMID: 23814276 PMCID: PMC3733146 DOI: 10.1093/jxb/ert159] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The Arabidopsis thaliana heterotrimeric G protein β subunit, AGB1, is involved in both abscisic acid (ABA) signalling and brassinosteroid (BR) signalling, but it is unclear how AGB1 regulates these signalling pathways. A key transcription factor downstream of BR, BZR1, and its gain-of-function mutant, bzr1-1, were overexpressed in an AGB1-null mutant, agb1-1, to examine their effects on the BR hyposensitivity and the ABA hypersensitivity of agb1-1, and to examine whether AGB1 regulates the functions of BZR1. Because the amino acid sequence of AGB1 contains 17 putative modification motifs of glycogen synthase kinase 3/SHAGGY-like protein kinases (GSKs), which are known components of BR signalling, the interaction between AGB1 and one of the Arabidopsis GSKs, BIN2, was examined. Expression of bzr1-1 alleviated the effects of a BR biosynthesis inhibitor, brassinazole, in both the wild type and agb1-1, and overexpression of BZR1 alleviated the effects of ABA in both the wild type and agb1-1. AGB1 did not affect the phosphorylation state of BZR1 in vivo. AGB1 interacted with BIN2 in vitro, but did not affect the phosphorylation state of BIN2. The results suggest that AGB1 interacts with BIN2, but regulates the BR signalling in a BZR1-independent manner.
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Affiliation(s)
- Daisuke Tsugama
- Asian Natural Environmental Science Center (ANESC), The University of Tokyo, 1-1-1 Midori-cho, Nishitokyo-shi, Tokyo 188-0002, Japan
| | - Shenkui Liu
- Alkali Soil Natural Environmental Science Center (ASNESC), Northeast Forestry University, Harbin 150040, PR China
| | - Tetsuo Takano
- Asian Natural Environmental Science Center (ANESC), The University of Tokyo, 1-1-1 Midori-cho, Nishitokyo-shi, Tokyo 188-0002, Japan
- *To whom correspondence should be addressed. E-mail:
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Urano D, Chen JG, Botella JR, Jones AM. Heterotrimeric G protein signalling in the plant kingdom. Open Biol 2013. [PMID: 23536550 DOI: 10.1098/rsob.12.0186] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2023] Open
Abstract
In animals, heterotrimeric G proteins, comprising α-, β-and γ-subunits, perceive extracellular stimuli through cell surface receptors, and transmit signals to ion channels, enzymes and other effector proteins to affect numerous cellular behaviours. In plants, G proteins have structural similarities to the corresponding molecules in animals but transmit signals by atypical mechanisms and effector proteins to control growth, cell proliferation, defence, stomate movements, channel regulation, sugar sensing and some hormonal responses. In this review, we summarize the current knowledge on the molecular regulation of plant G proteins, their effectors and the physiological functions studied mainly in two model organisms: Arabidopsis thaliana and rice (Oryza sativa). We also look at recent progress on structural analyses, systems biology and evolutionary studies.
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Affiliation(s)
- Daisuke Urano
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA
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20
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Urano D, Chen JG, Botella JR, Jones AM. Heterotrimeric G protein signalling in the plant kingdom. Open Biol 2013; 3:120186. [PMID: 23536550 PMCID: PMC3718340 DOI: 10.1098/rsob.120186] [Citation(s) in RCA: 178] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Accepted: 03/05/2013] [Indexed: 12/18/2022] Open
Abstract
In animals, heterotrimeric G proteins, comprising α-, β-and γ-subunits, perceive extracellular stimuli through cell surface receptors, and transmit signals to ion channels, enzymes and other effector proteins to affect numerous cellular behaviours. In plants, G proteins have structural similarities to the corresponding molecules in animals but transmit signals by atypical mechanisms and effector proteins to control growth, cell proliferation, defence, stomate movements, channel regulation, sugar sensing and some hormonal responses. In this review, we summarize the current knowledge on the molecular regulation of plant G proteins, their effectors and the physiological functions studied mainly in two model organisms: Arabidopsis thaliana and rice (Oryza sativa). We also look at recent progress on structural analyses, systems biology and evolutionary studies.
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Affiliation(s)
- Daisuke Urano
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Jin-Gui Chen
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - José Ramón Botella
- Plant Genetic Engineering Laboratory, School of Agriculture and Food Sciences, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Alan M. Jones
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC 27599, USA
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21
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Traverso JA, Micalella C, Martinez A, Brown SC, Satiat-Jeunemaître B, Meinnel T, Giglione C. Roles of N-terminal fatty acid acylations in membrane compartment partitioning: Arabidopsis h-type thioredoxins as a case study. THE PLANT CELL 2013; 25:1056-77. [PMID: 23543785 PMCID: PMC3634677 DOI: 10.1105/tpc.112.106849] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Revised: 02/22/2013] [Accepted: 03/04/2013] [Indexed: 05/18/2023]
Abstract
N-terminal fatty acylations (N-myristoylation [MYR] and S-palmitoylation [PAL]) are crucial modifications affecting 2 to 4% of eukaryotic proteins. The role of these modifications is to target proteins to membranes. Predictive tools have revealed unexpected targets of these acylations in Arabidopsis thaliana and other plants. However, little is known about how N-terminal lipidation governs membrane compartmentalization of proteins in plants. We show here that h-type thioredoxins (h-TRXs) cluster in four evolutionary subgroups displaying strictly conserved N-terminal modifications. It was predicted that one subgroup undergoes only MYR and another undergoes both MYR and PAL. We used plant TRXs as a model protein family to explore the effect of MYR alone or MYR and PAL in the same family of proteins. We used a high-throughput biochemical strategy to assess MYR of specific TRXs. Moreover, various TRX-green fluorescent protein fusions revealed that MYR localized protein to the endomembrane system and that partitioning between this membrane compartment and the cytosol correlated with the catalytic efficiency of the N-myristoyltransferase acting at the N terminus of the TRXs. Generalization of these results was obtained using several randomly selected Arabidopsis proteins displaying a MYR site only. Finally, we demonstrated that a palmitoylatable Cys residue flanking the MYR site is crucial to localize proteins to micropatching zones of the plasma membrane.
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Affiliation(s)
- José A. Traverso
- Centre National de la Recherche Scientifique, Centre de Recherche de Gif, Institut des Sciences du Végétal, F-91198 Gif-sur-Yvette cedex, France
- Consejo Superior de Investigaciones Científicas, Estación Experimental del Zaidín, C/ Profesor Albareda 1, Granada, Spain
| | - Chiara Micalella
- Centre National de la Recherche Scientifique, Centre de Recherche de Gif, Institut des Sciences du Végétal, F-91198 Gif-sur-Yvette cedex, France
| | - Aude Martinez
- Centre National de la Recherche Scientifique, Centre de Recherche de Gif, Institut des Sciences du Végétal, F-91198 Gif-sur-Yvette cedex, France
| | - Spencer C. Brown
- Centre National de la Recherche Scientifique, Centre de Recherche de Gif, Institut des Sciences du Végétal, F-91198 Gif-sur-Yvette cedex, France
| | - Béatrice Satiat-Jeunemaître
- Centre National de la Recherche Scientifique, Centre de Recherche de Gif, Institut des Sciences du Végétal, F-91198 Gif-sur-Yvette cedex, France
| | - Thierry Meinnel
- Centre National de la Recherche Scientifique, Centre de Recherche de Gif, Institut des Sciences du Végétal, F-91198 Gif-sur-Yvette cedex, France
| | - Carmela Giglione
- Centre National de la Recherche Scientifique, Centre de Recherche de Gif, Institut des Sciences du Végétal, F-91198 Gif-sur-Yvette cedex, France
- Address correspondence to
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