1
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Planchais S, Camborde L, Jupin I. Protocols for Studying Protein Stability in an Arabidopsis Protoplast Transient Expression System. Methods Mol Biol 2023; 2581:179-199. [PMID: 36413318 DOI: 10.1007/978-1-0716-2784-6_13] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Protein stability influences many aspects of biology, and measuring their stability in vivo can provide important insights into biological systems.This chapter describes in detail two methods to assess the stability of a specific protein based on its transient expression in Arabidopsis protoplasts. First, a pulse-chase assay based on radioactive metabolic labeling of cellular proteins, followed by immunoprecipitation of the protein of interest. The decrease in radioactive signal is monitored over time and can be used to determine the protein's half-life.Alternatively, we also present a nonradioactive assay based on the use of reporter proteins, whose ratio can be quantified. This assay can be used to determine the relative stability of a protein of interest under specific conditions.
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Affiliation(s)
- Séverine Planchais
- Laboratoire de Virologie Moléculaire, Institut Jacques Monod, CNRS, UMR 7592, Univ. Paris-Diderot, Sorbonne Paris Cité, Paris, France
- Unité URF5 « Adaptation des Plantes aux Contraintes Environnementales : Réponses Ecophysiologiques et Moléculaires», Univ. Pierre-et-Marie-Curie, Paris, France
| | - Laurent Camborde
- Laboratoire de Virologie Moléculaire, Institut Jacques Monod, CNRS, UMR 7592, Univ. Paris-Diderot, Sorbonne Paris Cité, Paris, France
- Laboratoire de Recherche en Sciences Végétales, CNRS, Univ. Toulouse Paul Sabatier, Toulouse, France
| | - Isabelle Jupin
- Laboratoire de Virologie Moléculaire, Institut Jacques Monod, CNRS, UMR 7592, Univ. Paris-Diderot, Sorbonne Paris Cité, Paris, France.
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Liu B, Xie Y, Yin H, Zhou Z, Liu Q. Identification and Defensive Characterization of PmCYP720B11v2 from Pinus massoniana. Int J Mol Sci 2022; 23:6640. [PMID: 35743081 PMCID: PMC9223603 DOI: 10.3390/ijms23126640] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 06/08/2022] [Accepted: 06/13/2022] [Indexed: 02/04/2023] Open
Abstract
Pinus massoniana is a pioneer species for afforestation timber and oleoresin, while epidemics of pinewood nematode (PWN; Bursaphelenchus xylophilus) are causing a serious biotic disaster for P. massoniana in China. Importantly, resistant P. massoniana could leak copious oleoresin terpenoids to build particular defense fronts for survival when attacked by PWN. However, the defense mechanisms regulating this process remain unknown. Here, PmCYP720B11v2, a cytochrome P450 monooxygenase gene, was first identified and functionally characterized from resistant P. massoniana following PWN inoculation. The tissue-specific expression pattern and localization of PmCYP720B11v2 at the transcript and protein levels in resistant P. massoniana indicated that its upregulation in the stem supported its involvement in the metabolic processes of diterpene biosynthesis as a positive part of the defense against PWN attack. Furthermore, overexpression of PmCYP720B11v2 may enhance the growth and development of plants. In addition, PmCYP720B11v2 activated the metabolic flux of antioxidases and stress-responsive proteins under drought conditions and improved drought stress tolerance. Our results provide new insights into the favorable role of PmCYP720B11v2 in diterpene defense mechanisms in response to PWN attack in resistant P. massoniana and provide a novel metabolic engineering scenario to reform the stress tolerance potential of tobacco.
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Affiliation(s)
- Bin Liu
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China; (B.L.); (Y.X.)
- Zhejiang Provincial Key Laboratory of Tree Breeding, Hangzhou 311400, China
| | - Yini Xie
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China; (B.L.); (Y.X.)
- Zhejiang Provincial Key Laboratory of Tree Breeding, Hangzhou 311400, China
| | - Huanhuan Yin
- Zhengzhou Botanical Garden, Zhengzhou 450007, China;
| | - Zhichun Zhou
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China; (B.L.); (Y.X.)
- Zhejiang Provincial Key Laboratory of Tree Breeding, Hangzhou 311400, China
| | - Qinghua Liu
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou 311400, China; (B.L.); (Y.X.)
- Zhejiang Provincial Key Laboratory of Tree Breeding, Hangzhou 311400, China
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3
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Liu B, Liu Q, Zhou Z, Yin H, Xie Y. Overexpression of geranyl diphosphate synthase (PmGPPS1) boosts monoterpene and diterpene production involved in the response to pine wood nematode invasion. TREE PHYSIOLOGY 2022; 42:411-424. [PMID: 34378055 DOI: 10.1093/treephys/tpab103] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Accepted: 07/30/2021] [Indexed: 06/13/2023]
Abstract
Outbreaks of pine wood nematode (PWN; Bursaphelenchus xylophilus) represent a severe biotic epidemic for the Pinus massoniana in China. When invaded by the PWN, the resistant P. massoniana might secret abundant oleoresin terpenoid to form certain defensive fronts for survival. However, the regulatory mechanisms of this process remain unclear. Here, the geranyl diphosphate synthase (PmGPPS1) gene was identified from resistant P. massoniana. Tissue-specific expression patterns of PmGPPS1 at transcript and protein level in resistant P. massoniana were determined by quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry. Functional characteristics analysis of PmGPPS1 was performed on transgenic Nicotiana benthamiana by overexpression, as genetic transformation of P. massoniana is, so far, not possible. In summary, we identified and functionally characterized PmGPPS1 from the resistant P. massoniana following PWN inoculation. Tissue-specific expression patterns and localization of PmGPPS1 indicated that it may play a positive role involved in the metabolic and defensive processes of oleoresin terpenes production in response to PWN attack. Furthermore, overexpression of PmGPPS1 may enhance the production of monoterpene, among which limonene reduced the survival of PWN in vitro. In addition, PmGPPS1 upregulated the expression level of key genes involved in mevalonic acid (MVA) pathway, the methylerythritol phosphate (MEP) pathway and gibberellins (GAs) biosynthesis to boost the growth and development of tobacco through a feedback regulation mechanism. Our results offered new insights into the pivotal role of the PmGPPS1 involved in terpene-based defense mechanisms responding to the PWN invasion in resistant P. massoniana and provided a new metabolic engineering scenario to improve monoterpene production in tobacco.
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Affiliation(s)
- Bin Liu
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou, 311400, China
- Zhejiang Provincial Key Laboratory of Tree Breeding, Hangzhou, Zhejiang 311400, China
| | - Qinghua Liu
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou, 311400, China
- Zhejiang Provincial Key Laboratory of Tree Breeding, Hangzhou, Zhejiang 311400, China
| | - Zhichun Zhou
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou, 311400, China
- Zhejiang Provincial Key Laboratory of Tree Breeding, Hangzhou, Zhejiang 311400, China
| | - Hengfu Yin
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou, 311400, China
| | - Yini Xie
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou, 311400, China
- Zhejiang Provincial Key Laboratory of Tree Breeding, Hangzhou, Zhejiang 311400, China
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Li W, Feng Z, Zhang C. Ammonium transporter PsAMT1.2 from Populus simonii functions in nitrogen uptake and salt resistance. TREE PHYSIOLOGY 2021; 41:2392-2408. [PMID: 34002233 DOI: 10.1093/treephys/tpab071] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 05/12/2021] [Indexed: 06/12/2023]
Abstract
Ammonium (NH4+) is a primary nitrogen (N) source for many species, and NH4+ uptake is mediated by various transporters. However, the effects of NH4+ transporters on N uptake and metabolism under salt stress remain unclear. In the present study, we investigated the expression characteristics and transport function of PsAMT1.2 in Populus simonii and its role in ammonium uptake and metabolism under salt stress. PsAMT1.2 was localized in the plasma membrane highly expressed in the roots. Heterologous functionality tests demonstrated that PsAMT1.2 mediates NH4+ permeation across the plasma membrane in yeast mutants, restoring growth. A short-term NH4+ uptake experiment showed that PsAMT1.2 is a high-affinity NH4+ transporter with a Km value of 80.603 μM for NH4+. Compared with the wild type (WT, Populus tremula × Populus alba INRA 717-IB4 genotype), PsAMT1.2-overexpressing transgenic poplar grew better, with higher increases in stem height and relative chlorophyll content under both control and salt-stress conditions. PsAMT1.2 overexpression significantly increased the total NH4+ concentration and total N of whole plants under salt stress. The glutamate synthase (GS), glutamine synthetase (GOGAT) and glutamate dehydrogenase (GDH) activities and the total amino acids largely increased in the roots of PsAMT1.2-overexpressing transgenic plants compared with the WT plants under control conditions, suggesting that PsAMT1.2 overexpression promotes NH4+ assimilation and metabolism in poplar roots. Consistent with the increased total amino acid content, GS1.3, GS2 and Fd-GOGAT expression was upregulated in the roots and leaves of the PsAMT1.2-overexpressing transgenic plants compared with the WT plants under salt stress. Collectively, PsAMT1.2 encodes a high-affinity NH4+ transporter crucial to NH4+ uptake and metabolism under salt stress.
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Affiliation(s)
- Wenxin Li
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, 26 Xinong Road, Yangling 712100, China
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China
| | - Zimao Feng
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China
| | - Chunxia Zhang
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, 26 Xinong Road, Yangling 712100, China
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China
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Li J, Meng Y, Zhang K, Li Q, Li S, Xu B, Georgiev MI, Zhou M. Jasmonic acid-responsive RRTF1 transcription factor controls DTX18 gene expression in hydroxycinnamic acid amide secretion. PLANT PHYSIOLOGY 2021; 185:369-384. [PMID: 33721896 PMCID: PMC8133619 DOI: 10.1093/plphys/kiaa043] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 10/23/2020] [Indexed: 05/18/2023]
Abstract
Jasmonates (JAs) are plant hormones that regulate the biosynthesis of many secondary metabolites, such as hydroxycinnamic acid amides (HCAAs), through jasmonic acid (JA)-responsive transcription factors (TFs). HCAAs are renowned for their role in plant defense against pathogens. The multidrug and toxic compound extrusion transporter DETOXIFICATION18 (DTX18) has been shown to mediate the extracellular accumulation of HCAAs p-coumaroylagmatine (CouAgm) at the plant surface for defense response. However, little is known about the regulatory mechanism of DTX18 gene expression by TFs. Yeast one-hybrid screening using the DTX18 promoter as bait isolated the key positive regulator redox-responsive TF 1 (RRTF1), which is a member of the AP2/ethylene-response factor family of proteins. RRTF1 is a JA-responsive factor that is required for the transcription of the DTX18 gene, and it thus promotes CouAgm secretion at the plant surface. As a result, overexpression of RRTF1 caused increased resistance against the fungus Botrytis cinerea, whereas rrtf1 mutant plants were more susceptible. Using yeast two-hybrid screening, we identified the BTB/POZ-MATH (BPM) protein BPM1 as an interacting partner of RRTF1. The BPM family of proteins acts as substrate adaptors of CUL3-based E3 ubiquitin ligases, and we found that only BPM1 and BPM3 were able to interact with RRTF1. In addition, we demonstrated that RRTF1 was subjected to degradation through the 26S proteasome pathway and that JA stabilized RRTF1. Knockout of BPM1 and BPM3 in bpm1/3 double mutants enhanced RRTF1 accumulation and DTX18 gene expression, thus increasing resistance to the fungus B. cinerea. Our results provide a better understanding of the fine-tuned regulation of JA-induced TFs in HCAA accumulation.
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Affiliation(s)
- Jinbo Li
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China
- Life Science College, Luoyang Normal University, Luoyang 471934, China
| | - Yu Meng
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China
- College of Landscape and Travel, Hebei Agricultural University, Baoding 071001, China
| | - Kaixuan Zhang
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Qiong Li
- School of Nursing, Hunan University of Chinese Medicine, Changsha 410208, China
| | - Shijuan Li
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China
- College of Plant Pathology, Gansu Agricultural University, Lanzhou 730070, China
| | - Bingliang Xu
- College of Plant Pathology, Gansu Agricultural University, Lanzhou 730070, China
| | - Milen I Georgiev
- Laboratory of Metabolomics, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Plovdiv, Bulgaria
- Center of Plant Systems Biology and Biotechnology, Plovdiv, Bulgaria
| | - Meiliang Zhou
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China
- Author for communication: (M.Z.)
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Glanc M, Van Gelderen K, Hoermayer L, Tan S, Naramoto S, Zhang X, Domjan D, Včelařová L, Hauschild R, Johnson A, de Koning E, van Dop M, Rademacher E, Janson S, Wei X, Molnár G, Fendrych M, De Rybel B, Offringa R, Friml J. AGC kinases and MAB4/MEL proteins maintain PIN polarity by limiting lateral diffusion in plant cells. Curr Biol 2021; 31:1918-1930.e5. [PMID: 33705718 PMCID: PMC8112251 DOI: 10.1016/j.cub.2021.02.028] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 01/22/2021] [Accepted: 02/12/2021] [Indexed: 12/22/2022]
Abstract
Polar subcellular localization of the PIN exporters of the phytohormone auxin is a key determinant of directional, intercellular auxin transport and thus a central topic of both plant cell and developmental biology. Arabidopsis mutants lacking PID, a kinase that phosphorylates PINs, or the MAB4/MEL proteins of unknown molecular function display PIN polarity defects and phenocopy pin mutants, but mechanistic insights into how these factors convey PIN polarity are missing. Here, by combining protein biochemistry with quantitative live-cell imaging, we demonstrate that PINs, MAB4/MELs, and AGC kinases interact in the same complex at the plasma membrane. MAB4/MELs are recruited to the plasma membrane by the PINs and in concert with the AGC kinases maintain PIN polarity through limiting lateral diffusion-based escape of PINs from the polar domain. The PIN-MAB4/MEL-PID protein complex has self-reinforcing properties thanks to positive feedback between AGC kinase-mediated PIN phosphorylation and MAB4/MEL recruitment. We thus uncover the molecular mechanism by which AGC kinases and MAB4/MEL proteins regulate PIN localization and plant development. MAB4/MEL proteins are recruited to the plasma membrane by PINs PINs, MAB4/MELs, and AGC kinases directly interact in a multiprotein complex PIN phosphorylation and MAB4/MEL recruitment form a positive feedback loop MAB4/MELs and AGC kinases maintain PIN polarity by limiting PIN lateral diffusion
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Affiliation(s)
- Matouš Glanc
- Institute of Science and Technology Austria (IST Austria), 3400 Klosterneuburg, Austria; Department of Experimental Plant Biology, Faculty of Science, Charles University, 12844 Prague, Czechia; Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium; VIB Center for Plant Systems Biology, 9052 Ghent, Belgium
| | - Kasper Van Gelderen
- Plant Developmental Genetics, Institute of Biology Leiden, Leiden University, 2333 BE Leiden, the Netherlands; Plant Ecophysiology, Institute of Environmental Biology, Utrecht University, 3584 CH Utrecht, the Netherlands
| | - Lukas Hoermayer
- Institute of Science and Technology Austria (IST Austria), 3400 Klosterneuburg, Austria
| | - Shutang Tan
- Institute of Science and Technology Austria (IST Austria), 3400 Klosterneuburg, Austria
| | - Satoshi Naramoto
- Department of Biological Sciences, Faculty of Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan
| | - Xixi Zhang
- Institute of Science and Technology Austria (IST Austria), 3400 Klosterneuburg, Austria
| | - David Domjan
- Institute of Science and Technology Austria (IST Austria), 3400 Klosterneuburg, Austria
| | - Ludmila Včelařová
- Institute of Science and Technology Austria (IST Austria), 3400 Klosterneuburg, Austria
| | - Robert Hauschild
- Institute of Science and Technology Austria (IST Austria), 3400 Klosterneuburg, Austria
| | - Alexander Johnson
- Institute of Science and Technology Austria (IST Austria), 3400 Klosterneuburg, Austria
| | - Edward de Koning
- Plant Developmental Genetics, Institute of Biology Leiden, Leiden University, 2333 BE Leiden, the Netherlands
| | - Maritza van Dop
- Plant Developmental Genetics, Institute of Biology Leiden, Leiden University, 2333 BE Leiden, the Netherlands
| | - Eike Rademacher
- Plant Developmental Genetics, Institute of Biology Leiden, Leiden University, 2333 BE Leiden, the Netherlands
| | - Stef Janson
- Plant Developmental Genetics, Institute of Biology Leiden, Leiden University, 2333 BE Leiden, the Netherlands
| | - Xiaoyu Wei
- Plant Developmental Genetics, Institute of Biology Leiden, Leiden University, 2333 BE Leiden, the Netherlands
| | - Gergely Molnár
- Institute of Science and Technology Austria (IST Austria), 3400 Klosterneuburg, Austria; Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, (BOKU), 1190 Vienna, Austria
| | - Matyáš Fendrych
- Institute of Science and Technology Austria (IST Austria), 3400 Klosterneuburg, Austria; Department of Experimental Plant Biology, Faculty of Science, Charles University, 12844 Prague, Czechia
| | - Bert De Rybel
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium; VIB Center for Plant Systems Biology, 9052 Ghent, Belgium
| | - Remko Offringa
- Plant Developmental Genetics, Institute of Biology Leiden, Leiden University, 2333 BE Leiden, the Netherlands.
| | - Jiří Friml
- Institute of Science and Technology Austria (IST Austria), 3400 Klosterneuburg, Austria.
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Liu B, Liu Q, Zhou Z, Yin H, Xie Y, Wei Y. Two terpene synthases in resistant Pinus massoniana contribute to defence against Bursaphelenchus xylophilus. PLANT, CELL & ENVIRONMENT 2021; 44:257-274. [PMID: 32833225 DOI: 10.1111/pce.13873] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Revised: 08/13/2020] [Accepted: 08/17/2020] [Indexed: 05/15/2023]
Abstract
Pine wood nematode (PWN; Bursaphelenchus xylophilus), a destructive pest of Pinus massoniana, is causing a severe epidemic of pine wilt disease in China. When invaded by PWN, resistant P. massoniana secretes an abundance of oleoresin terpenoids as a defensive strategy. However, regulatory mechanisms of this defence in resistant P. massoniana have yet to be elucidated. Here, we characterized two terpene synthase genes, α-pinene synthase (PmTPS4) and longifolene synthase (PmTPS21), identified in resistant P. massoniana and investigate the contribution of these genes to the oleoresin defence strategy in resistant masson pines. Up-regulation of these two genes in the stem supported their involvement in terpene biosynthesis as part of the defence against PWN. Recombinant protein expression revealed catalytic activity for the two PmTPSs, with PmTPS4 primarily producing α-pinene, while PmTPS21 produced α-pinene and longifolene simultaneously. The major enzymatic products of the two terpene synthases had inhibitory effects on PWN in vitro. We demonstrated that PmTPS4 and PmTPS21 played positive roles in terpene-defence mechanisms against PWN infestation. The major products of these terpene synthases could directly inhibit the survival rate of PWN in vitro. We revealed that PmTPS21 was a novel bifunctional enzyme capable of simultaneous production of both monoterpene and sesquiterpene.
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Affiliation(s)
- Bin Liu
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou, China
- Zhejiang Provincial Key Laboratory of Tree Breeding, Hangzhou, China
| | - Qinghua Liu
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou, China
- Zhejiang Provincial Key Laboratory of Tree Breeding, Hangzhou, China
| | - Zhichun Zhou
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou, China
- Zhejiang Provincial Key Laboratory of Tree Breeding, Hangzhou, China
| | - Hengfu Yin
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou, China
| | - Yini Xie
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou, China
- Zhejiang Provincial Key Laboratory of Tree Breeding, Hangzhou, China
| | - Yongcheng Wei
- Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou, China
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Li S, Xu B, Niu X, Lu X, Cheng J, Zhou M, Hooykaas PJJ. JAZ8 Interacts With VirE3 Attenuating Agrobacterium Mediated Root Tumorigenesis. FRONTIERS IN PLANT SCIENCE 2021; 12:685533. [PMID: 34868098 PMCID: PMC8639510 DOI: 10.3389/fpls.2021.685533] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 10/11/2021] [Indexed: 05/22/2023]
Abstract
Agrobacterium tumefaciens can cause crown gall tumors by transferring both an oncogenic piece of DNA (T-DNA) and several effector proteins into a wide range of host plants. For the translocated effector VirE3 multiple functions have been reported. It acts as a transcription factor in the nucleus binding to the Arabidopsis thaliana pBrp TFIIB-like protein to activate the expression of VBF, an F-box protein involved in degradation of the VirE2 and VIP1 proteins, facilitating Agrobacterium-mediated transformation. Also VirE3 has been found at the plasma membrane, where it could interact with VirE2. Here, we identified AtJAZ8 in a yeast two-hybrid screening with VirE3 as a bait and confirmed the interaction by pull-down and bimolecular fluorescence complementation assays. We also found that the deletion of virE3 reduced Agrobacterium virulence in a root tumor assay. Overexpression of virE3 in Arabidopsis enhanced tumorigenesis, whereas overexpression of AtJAZ8 in Arabidopsis significantly decreased the numbers of tumors formed. Further experiments demonstrated that AtJAZ8 inhibited the activity of VirE3 as a plant transcriptional regulator, and overexpression of AtJAZ8 in Arabidopsis activated AtPR1 gene expression while it repressed the expression of AtPDF1.2. Conversely, overexpression of virE3 in Arabidopsis suppressed the expression of AtPR1 whereas activated the expression of AtPDF1.2. Our results proposed a novel mechanism of counter defense signaling pathways used by Agrobacterium, suggesting that VirE3 and JAZ8 may antagonistically modulate the salicylic acid/jasmonic acid (SA/JA)-mediated plant defense signaling response during Agrobacterium infection.
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Affiliation(s)
- Shijuan Li
- College of Plant Protection, Gansu Agricultural University, Lanzhou, China
| | - Bingliang Xu
- College of Plant Protection, Gansu Agricultural University, Lanzhou, China
- *Correspondence: Bingliang Xu,
| | - Xiaolei Niu
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, College of Tropical Crops, Hainan University, Haikou, China
- Xiaolei Niu,
| | - Xiang Lu
- College of Agriculture, Guizhou University, Guiyang, China
| | - Jianping Cheng
- College of Agriculture, Guizhou University, Guiyang, China
| | - Meiliang Zhou
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
- Meiliang Zhou,
| | - Paul J. J. Hooykaas
- Department of Molecular and Developmental Genetics, Institute of Biology, Leiden University, Leiden, Netherlands
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Xiao Y, Offringa R. PDK1 regulates auxin transport and Arabidopsis vascular development through AGC1 kinase PAX. NATURE PLANTS 2020; 6:544-555. [PMID: 32393878 DOI: 10.1038/s41477-020-0650-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Accepted: 03/25/2020] [Indexed: 06/11/2023]
Abstract
The 3-phosphoinositide-dependent protein kinase 1 (PDK1) is a conserved master regulator of AGC kinases in eukaryotic organisms. pdk1 loss of function causes a lethal phenotype in animals and yeasts, but only mild phenotypic defects in Arabidopsis thaliana (Arabidopsis). The Arabidopsis genome contains two PDK1-encoding genes, PDK1 and PDK2. Here, we used clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9 (Cas9) to generate true loss-of-function pdk1 alleles, which, when combined with pdk2 alleles, showed severe developmental defects including fused cotyledons, a short primary root, dwarf stature and defects in male fertility. We obtained evidence that PDK1 is responsible for AGC1 kinase PROTEIN KINASE ASSOCIATED WITH BRX (PAX) activation by phosphorylation during vascular development, and that the PDK1 phospholipid-binding Pleckstrin Homology domain is not required for this process. Our data indicate that PDK1 regulates polar auxin transport by activating AGC1 clade kinases, resulting in PIN phosphorylation.
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Affiliation(s)
- Yao Xiao
- Plant Developmental Genetics, Institute of Biology Leiden, Leiden University, Leiden, the Netherlands
- Plant Systems Biology, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| | - Remko Offringa
- Plant Developmental Genetics, Institute of Biology Leiden, Leiden University, Leiden, the Netherlands.
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Wang Z, Wei X, Yang J, Li H, Ma B, Zhang K, Zhang Y, Cheng L, Ma F, Li M. Heterologous expression of the apple hexose transporter MdHT2.2 altered sugar concentration with increasing cell wall invertase activity in tomato fruit. PLANT BIOTECHNOLOGY JOURNAL 2020; 18:540-552. [PMID: 31350935 PMCID: PMC6953210 DOI: 10.1111/pbi.13222] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Revised: 07/17/2019] [Accepted: 07/19/2019] [Indexed: 05/08/2023]
Abstract
Sugar transporters are necessary to transfer hexose from cell wall spaces into parenchyma cells to boost hexose accumulation to high concentrations in fruit. Here, we have identified an apple hexose transporter (HTs), MdHT2.2, located in the plasma membrane, which is highly expressed in mature fruit. In a yeast system, the MdHT2.2 protein exhibited high 14 C-fructose and 14 C-glucose transport activity. In transgenic tomato heterologously expressing MdHT2.2, the levels of both fructose and glucose increased significantly in mature fruit, with sugar being unloaded via the apoplastic pathway, but the level of sucrose decreased significantly. Analysis of enzyme activity and the expression of genes related to sugar metabolism and transport revealed greatly up-regulated expression of SlLIN5, a key gene encoding cell wall invertase (CWINV), as well as increased CWINV activity in tomatoes transformed with MdHT2.2. Moreover, the levels of fructose, glucose and sucrose recovered nearly to those of the wild type in the sllin5-edited mutant of the MdHT2.2-expressing lines. However, the overexpression of MdHT2.2 decreased hexose levels and increased sucrose levels in mature leaves and young fruit, suggesting that the response pathway for the apoplastic hexose signal differs among tomato tissues. The present study identifies a new HTs in apple that is able to take up fructose and glucose into cells and confirms that the apoplastic hexose levels regulated by HT controls CWINV activity to alter carbohydrate partitioning and sugar content.
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Affiliation(s)
- Zhengyang Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas/College of Horticulture/Shaanxi Key Laboratory of AppleNorthwest A&F UniversityYanglingShaanxiChina
| | - Xiaoyu Wei
- State Key Laboratory of Crop Stress Biology for Arid Areas/College of Horticulture/Shaanxi Key Laboratory of AppleNorthwest A&F UniversityYanglingShaanxiChina
| | - Jingjing Yang
- State Key Laboratory of Crop Stress Biology for Arid Areas/College of Horticulture/Shaanxi Key Laboratory of AppleNorthwest A&F UniversityYanglingShaanxiChina
| | - Huixia Li
- State Key Laboratory of Crop Stress Biology for Arid Areas/College of Horticulture/Shaanxi Key Laboratory of AppleNorthwest A&F UniversityYanglingShaanxiChina
| | - Baiquan Ma
- State Key Laboratory of Crop Stress Biology for Arid Areas/College of Horticulture/Shaanxi Key Laboratory of AppleNorthwest A&F UniversityYanglingShaanxiChina
| | - Kaikai Zhang
- State Key Laboratory of Crop Stress Biology for Arid Areas/College of Horticulture/Shaanxi Key Laboratory of AppleNorthwest A&F UniversityYanglingShaanxiChina
| | - Yanfeng Zhang
- Hybrid Rape Research Center of Shaanxi ProvinceYanglingChina
| | - Lailiang Cheng
- Section of HorticultureSchool of Integrative Plant ScienceCornell UniversityIthacaNYUSA
| | - Fengwang Ma
- State Key Laboratory of Crop Stress Biology for Arid Areas/College of Horticulture/Shaanxi Key Laboratory of AppleNorthwest A&F UniversityYanglingShaanxiChina
| | - Mingjun Li
- State Key Laboratory of Crop Stress Biology for Arid Areas/College of Horticulture/Shaanxi Key Laboratory of AppleNorthwest A&F UniversityYanglingShaanxiChina
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11
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Zhang X, Hooykaas PJJ. The Agrobacterium VirD5 protein hyperactivates the mitotic Aurora kinase in host cells. THE NEW PHYTOLOGIST 2019; 222:1551-1560. [PMID: 30667529 PMCID: PMC6667905 DOI: 10.1111/nph.15700] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 01/13/2019] [Indexed: 06/08/2023]
Abstract
Aided by translocated virulence proteins, Agrobacterium tumefaciens transforms plant cells with oncogenic T-DNA. In the host cells the virulence protein VirD5 moves to the nucleus, where it becomes localized at the kinetochores, and disturbs faithful chromosome segregation, but the molecular mechanism underlying this remains unknown. To gain more insight, we screened amongst the kinetochore proteins for VirD5 interactors using bimolecular fluorescence complementation assays, and tested chromosome segregation in yeast cells. We found that VirD5 interacts with the conserved mitotic Aurora kinase Ipl1 in yeast and likewise with plant Aurora kinases. In vitro VirD5 was found to stimulate the activity of Ipl1. Phosphorylation of substrates by Ipl1 in vivo is known to result in the detachment between kinetochore and spindle microtubule. This is necessary for error correction, but increased Ipl1/Aurora kinase activity is known to cause spindle instability, explaining enhanced chromosome mis-segregation seen in the presence of VirD5. That activation of the Ipl1/Aurora kinase at least partially underlies the toxicity of VirD5 became apparent by artificial boosting the activity of the specific counteracting phosphatase Glc7 in vivo, which relieved the toxicity. These findings reveal a novel mechanism by which a pathogenic bacterium manipulates host cells.
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Affiliation(s)
- Xiaorong Zhang
- Department of Molecular and Developmental GeneticsInstitute of BiologyLeiden UniversitySylviusweg 72Leiden2333BEthe Netherlands
| | - Paul J. J. Hooykaas
- Department of Molecular and Developmental GeneticsInstitute of BiologyLeiden UniversitySylviusweg 72Leiden2333BEthe Netherlands
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12
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Zhang S, Habets M, Breuninger H, Dolan L, Offringa R, van Duijn B. Evolutionary and Functional Analysis of a Chara Plasma Membrane H +-ATPase. FRONTIERS IN PLANT SCIENCE 2019; 10:1707. [PMID: 32038681 PMCID: PMC6985207 DOI: 10.3389/fpls.2019.01707] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 12/04/2019] [Indexed: 05/12/2023]
Abstract
H+-ATPases are the main transporters in plant and fungal plasma membranes (PMs), comparable to the Na+/K+ ATPases in animal cells. At the molecular level, most studies on the PM H+-ATPases have been focused on land plants and fungi (yeast). The research of PM H+-ATPases in green algae falls far behind due to the lack of genetic information. Here we studied a potential PM H+-ATPase (CHA1) from Chara australis, a species of green algae belonging to the division Charophyta, members of which are considered to be one of the closest ancestors of land plants. The gene encodes a 107 kDa protein with all 6 P-type ATPase-specific motifs and a long, diverse C-terminal domain. A new amino acid sequence motif R*****Q in transmembrane segment 5 was identified among the known PM H+-ATPases from Charophyta and Chlorophyta algae, which is different from the typical PM H+-ATPases in yeast or land plants. Complementation analysis in yeast showed that CHA1 could successfully reach the PM, and that proton pump activity was obtained when the last 77 up to 87 amino acids of the C-terminal domain were deleted. PM localization was confirmed in Arabidopsis protoplasts; however, deletion of more than 55 amino acids at the N-terminus or more than 98 amino acids at the C-terminus resulted in failure of CHA1 to reach the PM in yeast. These results suggest that an auto-inhibition domain is located in the C-terminal domain, and that CHA1 is likely to have a different regulation mechanism compared to the yeast and land plant PM H+-ATPases.
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Affiliation(s)
- Suyun Zhang
- Plant Biodynamics Laboratory, Institute of Biology Leiden, Leiden University, Leiden, Netherlands
- Plant Developmental Genetics, Institute of Biology Leiden, Leiden University, Leiden, Netherlands
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, China
| | - Myckel Habets
- Plant Developmental Genetics, Institute of Biology Leiden, Leiden University, Leiden, Netherlands
| | - Holger Breuninger
- Department of Plant Sciences, University of Oxford, Oxford, United Kingdom
| | - Liam Dolan
- Department of Plant Sciences, University of Oxford, Oxford, United Kingdom
| | - Remko Offringa
- Plant Developmental Genetics, Institute of Biology Leiden, Leiden University, Leiden, Netherlands
| | - Bert van Duijn
- Plant Biodynamics Laboratory, Institute of Biology Leiden, Leiden University, Leiden, Netherlands
- Research Department, Fytagoras BV, Leiden, Netherlands
- *Correspondence: Bert van Duijn,
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13
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Roushan MR, de Zeeuw MAM, Hooykaas PJJ, van Heusden GPH. Application of phiLOV2.1 as a fluorescent marker for visualization of Agrobacterium effector protein translocation. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2018; 96:685-699. [PMID: 30098065 DOI: 10.1111/tpj.14060] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 07/31/2018] [Indexed: 06/08/2023]
Abstract
Agrobacterium tumefaciens can genetically transform plants by translocating a piece of oncogenic DNA, called T-DNA, into host cells. Transfer is mediated by a type IV secretion system (T4SS). Besides the T-DNA, which is transferred in a single-stranded form and at its 5' end covalently bound to VirD2, several other effector proteins (VirE2, VirE3, VirD5, and VirF) are translocated into the host cells. The fate and function of the translocated proteins inside the host cell are only partly known. Therefore, several studies were conducted to visualize the translocation of the VirE2 protein. As GFP-tagged effector proteins are unable to pass the T4SS, other approaches like the split GFP system were used, but these require specific transgenic recipient cells expressing the complementary part of GFP. Here, we investigated whether use can be made of the photostable variant of LOV, phiLOV2.1, to visualize effector protein translocation from Agrobacterium to non-transgenic yeast and plant cells. We were able to visualize the translocation of all five effector proteins, both to yeast cells, and to cells in Nicotiana tabacum leaves and Arabidopsis thaliana roots. Clear signals were obtained that are easily distinguishable from the background, even in cases in which by comparison the split GFP system did not generate a signal.
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Affiliation(s)
- Mohammad Reza Roushan
- Department of Molecular and Developmental Genetics, Institute of Biology Leiden, Faculty of Science, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands
| | - Milou A M de Zeeuw
- Department of Molecular and Developmental Genetics, Institute of Biology Leiden, Faculty of Science, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands
| | - Paul J J Hooykaas
- Department of Molecular and Developmental Genetics, Institute of Biology Leiden, Faculty of Science, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands
| | - Gerard Paul H van Heusden
- Department of Molecular and Developmental Genetics, Institute of Biology Leiden, Faculty of Science, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands
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14
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Li J, Zhang K, Meng Y, Hu J, Ding M, Bian J, Yan M, Han J, Zhou M. Jasmonic acid/ethylene signaling coordinates hydroxycinnamic acid amides biosynthesis through ORA59 transcription factor. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2018; 95:444-457. [PMID: 29752755 DOI: 10.1111/tpj.13960] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 04/22/2018] [Accepted: 04/25/2018] [Indexed: 05/19/2023]
Abstract
Hydroxycinnamic acid amides (HCAAs) are a class of antimicrobial metabolites involved in plant defense against necrotrophic pathogens, including Alternaria brassicicola and Botrytis cinerea. The agmatine coumaryl transferase (AtACT) is the key enzyme that catalyzes the last reaction in the biosynthesis of HCAAs, including p-coumaroylagmatine (CouAgm) and feruloylagmatine in Arabidopsis thaliana. However, the regulatory mechanism of AtACT gene expression is currently unknown. Yeast one-hybrid screening using the AtACT promoter as bait isolated the key positive regulator ORA59 that is involved in jasmonic acid/ethylene (JA/ET)-mediated plant defense responses. AtACT gene expression and HCAAs biosynthesis were synergistically induced by a combination of JA and ET. In the AtACT promoter, two GCC-boxes function equivalently for trans-activation by ORA59 in Arabidopsis protoplasts, and mutation of either GCC-box abolished AtACT mRNA accumulation in transgenic plants. Site-directed mutation analysis demonstrated that the specific Leu residue at position 228 of the ORA59 EDLL motif mainly contributed to its transcriptional activity on AtACT gene expression. Importantly, MEDIATOR25 (MED25) and ORA59 homodimer are also required for ORA59-dependent activation of the AtACT gene. These results suggest that ORA59 and two functionally equivalent GCC-boxes form the regulatory module together with MED25 that enables AtACT gene expression and HCAAs biosynthesis to respond to simultaneous activation of the JA/ET signaling pathways.
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Affiliation(s)
- Jinbo Li
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
- Life Science College, Luoyang Normal University, Luoyang, 471934, China
| | - Kaixuan Zhang
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Yu Meng
- College of Landscape and Travel, Agricultural University of Hebei, Baoding, 071001, China
| | - Jianping Hu
- College of Agricultural Science, Xichang University, Xichang, 615000, Sichuan, China
| | - Mengqi Ding
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Jiahui Bian
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Mingli Yan
- School of Life Sciences, Hunan University of Science and Technology, Xiangtan, 411201, Hunan, China
| | - Jianming Han
- Life Science College, Luoyang Normal University, Luoyang, 471934, China
| | - Meiliang Zhou
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
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15
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Zhang K, Logacheva MD, Meng Y, Hu J, Wan D, Li L, Janovská D, Wang Z, Georgiev MI, Yu Z, Yang F, Yan M, Zhou M. Jasmonate-responsive MYB factors spatially repress rutin biosynthesis in Fagopyrum tataricum. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:1955-1966. [PMID: 29394372 PMCID: PMC6018783 DOI: 10.1093/jxb/ery032] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 01/16/2018] [Indexed: 05/17/2023]
Abstract
Jasmonates are plant hormones that induce the accumulation of many secondary metabolites, such as rutin in buckwheat, via regulation of jasmonate-responsive transcription factors. Here, we report on the identification of a clade of jasmonate-responsive subgroup 4 MYB transcription factors, FtMYB13, FtMYB14, FtMYB15, and FtMYB16, which directly repress rutin biosynthesis in Fagopyrum tataricum. Immunoblot analysis showed that FtMYB13, FtMYB14, and FtMYB15 could be degraded via the 26S proteasome in the COI1-dependent jasmonate signaling pathway, and that this degradation is due to the SID motif in their C-terminus. Yeast two-hybrid and bimolecular fluorescence complementation assays revealed that FtMYB13, FtMYB14, and FtMYB15 interact with the importin protein Sensitive to ABA and Drought 2 (FtSAD2) in stem and inflorescence. Furthermore, the key repressor of jasmonate signaling FtJAZ1 specifically interacts with FtMYB13. Point mutation analysis showed that the conserved Asp residue of the SID domain contributes to mediating protein-protein interaction. Protoplast transient activation assays demonstrated that FtMYB13, FtMYB14, and FtMYB15 directly repress phenylalanine ammonia lyase (FtPAL) gene expression, and FtSAD2 and FtJAZ1 significantly promote the repressing activity of FtMYBs. These findings may ultimately be promising for further engineering of plant secondary metabolism.
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Affiliation(s)
- Kaixuan Zhang
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Maria D Logacheva
- Department of Evolutionary Biochemistry, AN Belozersky Institute of Physico-Chemical Biology, MV Lomonosov Moscow State University, Moscow, Russia
| | - Yu Meng
- College of Landscape and Travel, Agricultural University of Hebei, Baoding, China
| | - Jianping Hu
- College of Agricultural Science, Xichang University, Xichang, Sichuan, China
| | - Dongpu Wan
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China
- College of Agriculture, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia, China
| | - Long Li
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China
- School of Life Sciences, Hunan University of Science and Technology, Xiangtan, Hunan, China
| | - Dagmar Janovská
- Department of Gene Bank, Crop Research Institute, Drnovská, Czech Republic
| | - Zhiyong Wang
- College of Agriculture, Hainan University, Haikou, Hainan, China
| | - Milen I Georgiev
- Group of Plant Cell Biotechnology and Metabolomics, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Plovdiv, Bulgaria
- Center of Plant Systems Biology and Biotechnology, Plovdiv, Bulgaria
| | - Zhuo Yu
- College of Agriculture, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia, China
| | - Fuyu Yang
- Grassland Institute, China Agricultural University, Beijing, China
| | - Mingli Yan
- School of Life Sciences, Hunan University of Science and Technology, Xiangtan, Hunan, China
| | - Meiliang Zhou
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China
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16
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Yao P, Sun Z, Li C, Zhao X, Li M, Deng R, Huang Y, Zhao H, Chen H, Wu Q. Overexpression of Fagopyrum tataricum FtbHLH2 enhances tolerance to cold stress in transgenic Arabidopsis. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2018; 125:85-94. [PMID: 29427891 DOI: 10.1016/j.plaphy.2018.01.028] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 01/20/2018] [Accepted: 01/26/2018] [Indexed: 05/20/2023]
Abstract
bHLH transcription factors play important roles in the abiotic stress response in plants, but their characteristics and functions in Tartary buckwheat (Fagopyrum tataricum), a traditional coarse cereal with a strong stress tolerance, haven't been sufficiently studied. Here, we found that the expression of a bHLH gene, FtbHLH2, was induced significantly by cold treatments in Tartary buckwheat seedlings. Subcellular localization indicated that FtbHLH2 localized in nucleus. Its overexpression in Arabidopsis increased tolerance to cold. The Arabidopsis plants overexpressing FtbHLH2 displayed higher root length and photosynthetic efficiency, and had lower malondialdehyde (MDA) and reactive oxygen species (ROS) after cold treatment compared to wild type (WT) plants. Meanwhile, the expression levels of some stress-related genes in transgenic plants were remarkably higher than that in wild type under normal and/or stress conditions. Furthermore, transgenic Arabidopsis lines with the FtbHLH2 promoter had higher GUS activity after cold stress. On the whole, the results suggest that FtbHLH2 may play a positive regulatory in cold stress of Tartary buckwheat.
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Affiliation(s)
- Panfeng Yao
- College of Life Science, Sichuan Agricultural University, Ya'an, 625014, Sichuan Province, China
| | - Zhaoxia Sun
- College of Agronomy, Shanxi Agricultural University, Shanxi Province, China
| | - Chenglei Li
- College of Life Science, Sichuan Agricultural University, Ya'an, 625014, Sichuan Province, China
| | - Xuerong Zhao
- College of Life Science, Sichuan Agricultural University, Ya'an, 625014, Sichuan Province, China
| | - Maofei Li
- College of Life Science, Sichuan Agricultural University, Ya'an, 625014, Sichuan Province, China
| | - Renyu Deng
- College of Life Science, Sichuan Agricultural University, Ya'an, 625014, Sichuan Province, China
| | - Yunji Huang
- College of Life Science, Sichuan Agricultural University, Ya'an, 625014, Sichuan Province, China
| | - Haixia Zhao
- College of Life Science, Sichuan Agricultural University, Ya'an, 625014, Sichuan Province, China
| | - Hui Chen
- College of Life Science, Sichuan Agricultural University, Ya'an, 625014, Sichuan Province, China
| | - Qi Wu
- College of Life Science, Sichuan Agricultural University, Ya'an, 625014, Sichuan Province, China.
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17
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Hussain RMF, Sheikh AH, Haider I, Quareshy M, Linthorst HJM. Arabidopsis WRKY50 and TGA Transcription Factors Synergistically Activate Expression of PR1. FRONTIERS IN PLANT SCIENCE 2018; 9:930. [PMID: 30057584 PMCID: PMC6053526 DOI: 10.3389/fpls.2018.00930] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Accepted: 06/11/2018] [Indexed: 05/18/2023]
Abstract
Arabidopsis PR1 is a salicylic acid (SA) inducible marker gene for systemic acquired resistance (SAR). However, the regulation of PR1 in plants is poorly understood. In this study, we showed that AtWRKY50 transcription factor binds to two promoter elements of PR1 via its DNA binding domain. Interestingly, the DNA-binding sites for AtWRKY50 deviate significantly from the consensus WRKY binding W-box. The binding sites are located in close proximity to the binding sites for TGA transcription factors. Transactivation experiments in Arabidopsis protoplasts derived from wild type, npr1-1 and tga256 mutant plants indicated that AtWRKY50 alone was able to induce expression of a PR1::β-glucuronidase (GUS) reporter gene, independent of TGAs or NPR1. However, co-expression of TGA2 or TGA5 with AtWRKY50 synergistically enhanced expression to high levels. Yeast-2-hybrid assays and bimolecular fluorescence complementation (BiFC) experiments revealed that AtWRKY50 could interact with TGA2 and TGA5. Using electrophoretic mobility shift assays (EMSA) it was established that AtWRKY50 and TGA2 or TGA5 simultaneously bind to the PR1 promoter. Taken together, these results support a role of AtWRKY50 in SA-induced expression of PR1. Highlights: AtWRKY50 specifically binds to LS10 region of PR1 promoter and interacts with TGAs to synergistically activate PR1 expression.
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Affiliation(s)
| | - Arsheed H. Sheikh
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
- *Correspondence: Arsheed H. Sheikh,
| | - Imran Haider
- Institute of Biology, Leiden University, Leiden, Netherlands
- Laboratory of Plant Physiology, Wageningen University, Wageningen, Netherlands
| | - Mussa Quareshy
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
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18
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Zhou M, Sun Z, Ding M, Logacheva MD, Kreft I, Wang D, Yan M, Shao J, Tang Y, Wu Y, Zhu X. FtSAD2 and FtJAZ1 regulate activity of the FtMYB11 transcription repressor of the phenylpropanoid pathway in Fagopyrum tataricum. THE NEW PHYTOLOGIST 2017; 216:814-828. [PMID: 28722263 DOI: 10.1111/nph.14692] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Accepted: 06/06/2017] [Indexed: 05/21/2023]
Abstract
Little is known about the molecular mechanism of the R2R3-MYB transcriptional repressors involved in plant phenylpropanoid metabolism. Here, we describe one R2R3-type MYB repressor, FtMYB11 from Fagopyrum tataricum. It contains the SID-like motif GGDFNFDL and it is regulated by both the importin protein 'Sensitive to ABA and Drought 2' (SAD2) and the jasmonates signalling cascade repressor JAZ protein. Yeast two hybrid and bimolecular fluorescence complementation assays demonstrated that FtMYB11 interacts with SAD2 and FtJAZ1. Protoplast transactivation assays demonstrated that FtMYB11 acts synergistically with FtSAD2 or FtJAZ1 and directly represses its target genes via the MYB-core element AATAGTT. Changing the Asp122 residue to Asn in the SID-like motif results in cytoplasmic localization of FtMYB11 because of loss of interaction with SAD2, while changing the Asp126 residue to Asn results in the loss of interaction with FtJAZ1. Overexpression of FtMYB11or FtMYB11D126N in F. tataricum hairy roots resulted in reduced accumulation of rutin, while overexpression of FtMYB11D122N in hairy roots did not lead to such a change. The results indicate that FtMYB11 acts as a regulator via interacting with FtSAD2 or FtJAZ1 to repress phenylpropanoid biosynthesis, and this repression depends on two conserved Asp residues of its SID-like motif.
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Affiliation(s)
- Meiliang Zhou
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
- College of Environmental Sciences, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Zhanmin Sun
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Mengqi Ding
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Maria D Logacheva
- Department of Evolutionary Biochemistry, AN Belozersky Institute of Physico-Chemical Biology, MV Lomonosov, Moscow State University, Moscow, Russia
| | - Ivan Kreft
- Nutrition Institute, Tržaška 40, SI-1000, Ljubljana, Slovenia
| | - Dan Wang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Mingli Yan
- School of Life Sciences, Hunan University of Science and Technology, Xiangtan, 411201, Hunan, China
| | - Jirong Shao
- College of Life Sciences, Sichuan Agricultural University, Yaan, 625014, Sichuan, China
| | - Yixiong Tang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Yanmin Wu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Xuemei Zhu
- College of Environmental Sciences, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
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19
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Yao PF, Li CL, Zhao XR, Li MF, Zhao HX, Guo JY, Cai Y, Chen H, Wu Q. Overexpression of a Tartary Buckwheat Gene, FtbHLH3, Enhances Drought/Oxidative Stress Tolerance in Transgenic Arabidopsis. FRONTIERS IN PLANT SCIENCE 2017; 8:625. [PMID: 28487715 PMCID: PMC5403918 DOI: 10.3389/fpls.2017.00625] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2017] [Accepted: 04/06/2017] [Indexed: 05/05/2023]
Abstract
bHLH (basic helix-loop-helix) transcription factors play important roles in the abiotic stress response in plants, but their characteristics and functions in tartary buckwheat (Fagopyrum tataricum), a flavonoid-rich cereal crop with a strong stress tolerance, have not been fully investigated. Here, a novel bHLH gene, designated FtbHLH3, was isolated and characterized. Expression analysis in tartary buckwheat revealed that FtbHLH3 was mainly induced by polyethylene glycol 6000 (PEG6000) and abscisic acid (ABA) treatments. Subcellular localization and a yeast one-hybrid assay indicated that FtbHLH3 has transcriptional activation activities. Overexpression of FtbHLH3 in Arabidopsis resulted in increased drought/oxidative tolerance, which was attributed to not only lower malondialdehyde (MDA), ion leakage (IL), and reactive oxygen species (ROS) but also higher proline (Pro) content, activities of antioxidant enzymes, and photosynthetic efficiency in transgenic lines compared to wild type (WT). Moreover, qRT-PCR analysis indicated that the expression of multiple stress-responsive genes in the transgenic lines was significantly higher than in WT under drought stress. In particular, the expression of AtNCED, a rate-limiting enzyme gene in ABA biosynthesis, was increased significantly under both normal and stress conditions. Additionally, an ABA-response-element (ABRE) was also found in the promoter regions. Furthermore, the transgenic Arabidopsis lines of the FtbHLH3 promoter had higher GUS activity after drought stress. In summary, our results indicated that FtbHLH3 may function as a positive regulator of drought/oxidative stress tolerance in transgenic Arabidopsis through an ABA-dependent pathway.
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Brikis CJ, Zarei A, Trobacher CP, DeEll JR, Akama K, Mullen RT, Bozzo GG, Shelp BJ. Ancient Plant Glyoxylate/Succinic Semialdehyde Reductases: GLYR1s Are Cytosolic, Whereas GLYR2s Are Localized to Both Mitochondria and Plastids. FRONTIERS IN PLANT SCIENCE 2017; 8:601. [PMID: 28484477 PMCID: PMC5399074 DOI: 10.3389/fpls.2017.00601] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 04/03/2017] [Indexed: 05/18/2023]
Abstract
Plant NADPH-dependent glyoxylate/succinic semialdehyde reductases 1 and 2 (GLYR1 and GLYR2) are considered to be involved in detoxifying harmful aldehydes, thereby preserving plant health during exposure to various abiotic stresses. Phylogenetic analysis revealed that the two GLYR isoforms appeared in the plant lineage prior to the divergence of the Chlorophyta and Streptophyta, which occurred approximately 750 million years ago. Green fluorescent protein fusions of apple (Malus x domestica Borkh.), rice (Oryza sativa L.) and Arabidopsis thaliana [L.] Heynh GLYRs were transiently expressed in tobacco (Nicotiana tabaccum L.) suspension cells or Arabidopsis protoplasts, as well in methoxyfenozide-induced, stably transformed Arabidopsis seedlings. The localization of apple GLYR1 confirmed that this isoform is cytosolic, whereas apple, rice and Arabidopsis GLYR2s were localized to both mitochondria and plastids. These findings highlight the potential involvement of GLYRs within distinct compartments of the plant cell.
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Affiliation(s)
| | - Adel Zarei
- Department of Plant Agriculture, University of Guelph, GuelphON, Canada
| | | | - Jennifer R. DeEll
- Ontario Ministry of Agriculture Food and Rural Affairs, SimcoeON, Canada
| | - Kazuhito Akama
- Department of Biological Science, Shimane UniversityMatsue, Japan
| | - Robert T. Mullen
- Department of Molecular and Cellular Biology, University of Guelph, GuelphON, Canada
| | - Gale G. Bozzo
- Department of Plant Agriculture, University of Guelph, GuelphON, Canada
| | - Barry J. Shelp
- Department of Plant Agriculture, University of Guelph, GuelphON, Canada
- *Correspondence: Barry J. Shelp,
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Arabidopsis aldehyde dehydrogenase 10 family members confer salt tolerance through putrescine-derived 4-aminobutyrate (GABA) production. Sci Rep 2016; 6:35115. [PMID: 27725774 PMCID: PMC5057122 DOI: 10.1038/srep35115] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 09/26/2016] [Indexed: 11/26/2022] Open
Abstract
Polyamines represent a potential source of 4-aminobutyrate (GABA) in plants exposed to abiotic stress. Terminal catabolism of putrescine in Arabidopsis thaliana involves amine oxidase and the production of 4-aminobutanal, which is a substrate for NAD+-dependent aminoaldehyde dehydrogenase (AMADH). Here, two AMADH homologs were chosen (AtALDH10A8 and AtALDH10A9) as candidates for encoding 4-aminobutanal dehydrogenase activity for GABA synthesis. The two genes were cloned and soluble recombinant proteins were produced in Escherichia coli. The pH optima for activity and catalytic efficiency of recombinant AtALDH10A8 with 3-aminopropanal as substrate was 10.5 and 8.5, respectively, whereas the optima for AtALDH10A9 were approximately 9.5. Maximal activity and catalytic efficiency were obtained with NAD+ and 3-aminopropanal, followed by 4-aminobutanal; negligible activity was obtained with betaine aldehyde. NAD+ reduction was accompanied by the production of GABA and β-alanine, respectively, with 4-aminobutanal and 3-aminopropanal as substrates. Transient co-expression systems using Arabidopsis cell suspension protoplasts or onion epidermal cells and several organelle markers revealed that AtALDH10A9 was peroxisomal, but AtALDH10A8 was cytosolic, although the N-terminal 140 amino acid sequence of AtALDH10A8 localized to the plastid. Root growth of single loss-of-function mutants was more sensitive to salinity than wild-type plants, and this was accompanied by reduced GABA accumulation.
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22
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Zhou Y, Sun X, Yang Y, Li X, Cheng Y, Yang Y. Expression of Stipa purpurea SpCIPK26 in Arabidopsis thaliana Enhances Salt and Drought Tolerance and Regulates Abscisic Acid Signaling. Int J Mol Sci 2016; 17:ijms17060966. [PMID: 27338368 PMCID: PMC4926498 DOI: 10.3390/ijms17060966] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 04/13/2016] [Accepted: 05/18/2016] [Indexed: 11/16/2022] Open
Abstract
Stipa purpurea (S. purpurea) is the dominant plant species in the alpine steppe of the Qinghai-Tibet Plateau, China. It is highly resistant to cold and drought conditions. However, the underlying mechanisms regulating the stress tolerance are unknown. In this study, a CIPK gene from S. purpurea (SpCIPK26) was isolated. The SpCIPK26 coding region consisted of 1392 bp that encoded 464 amino acids. The protein has a highly conserved catalytic structure and regulatory domain. The expression of SpCIPK26 was induced by drought and salt stress. SpCIPK26 overexpression in Arabidopsis thaliana (A. thaliana) plants provided increased tolerance to drought and salt stress in an abscisic acid (ABA)-dependent manner. Compared with wild-type A. thaliana plants, SpCIPK26-overexpressing plants had higher survival rates, water potentials, and photosynthetic efficiency (Fv/Fm), as well as lower levels of reactive oxygen species (ROS) following exposure to drought and salt stress. Gene expression analyses indicated stress-inducible genes (RD29A, RD29B, and ABF2) and a ROS-scavenger gene (CAT1) were upregulated in SpCIPK26-overexpressing plants after stress treatments. All of these marker genes are associated with ABA-responsive cis-acting elements. Additionally, the similarities in the gene expression patterns following ABA, mannitol, and NaCl treatments suggest SpCIPK26 has an important role during plant responses to drought and salt stress and in regulating ABA signaling.
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Affiliation(s)
- Yanli Zhou
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.
- Plant Germplasm and Genomics Center, the Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.
- University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Xudong Sun
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.
- Plant Germplasm and Genomics Center, the Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.
- Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.
| | - Yunqiang Yang
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.
- Plant Germplasm and Genomics Center, the Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.
- Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.
| | - Xiong Li
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.
- Plant Germplasm and Genomics Center, the Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.
- Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.
| | - Ying Cheng
- College of Horticulture and Landscape, Yunnan Agricultural University, Kunming 650201, China.
| | - Yongping Yang
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.
- Plant Germplasm and Genomics Center, the Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.
- University of Chinese Academy of Sciences, Beijing 100049, China.
- Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.
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Protocols for Studying Protein Stability in an Arabidopsis Protoplast Transient Expression System. Methods Mol Biol 2016; 1450:175-94. [PMID: 27424754 DOI: 10.1007/978-1-4939-3759-2_14] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Protein stability influences many aspects of biology, and measuring their stability in vivo can provide important insights into biological systems.This chapter describes in details two methods to assess the stability of a specific protein based on its transient expression in Arabidopsis protoplasts. First, a pulse-chase assay based on radioactive metabolic labeling of cellular proteins, followed by immunoprecipitation of the protein of interest. The decrease in radioactive signal is monitored over time and can be used to determine the protein's half-life.Alternatively, we also present a nonradioactive assay based on the use of reporter proteins, whose ratio can be quantified. This assay can be used to determine the relative stability of a protein of interest under specific conditions.
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24
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Niu X, Zhou M, Henkel CV, van Heusden GPH, Hooykaas PJJ. The Agrobacterium tumefaciens virulence protein VirE3 is a transcriptional activator of the F-box gene VBF. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2015; 84:914-924. [PMID: 26461850 DOI: 10.1111/tpj.13048] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 09/25/2015] [Accepted: 10/01/2015] [Indexed: 05/29/2023]
Abstract
During Agrobacterium tumefaciens-mediated transformation of plant cells a part of the tumour-inducing plasmid, T-DNA, is integrated into the host genome. In addition, a number of virulence proteins are translocated into the host cell. The virulence protein VirE3 binds to the Arabidopsis thaliana pBrp protein, a plant-specific general transcription factor of the TFIIB family. To study a possible role for VirE3 in transcriptional regulation, we stably expressed virE3 in A. thaliana under control of a tamoxifen-inducible promoter. By RNA sequencing we showed that upon expression of virE3 the RNA levels of 607 genes were increased more than three-fold and those of 132 genes decreased more than three-fold. One of the strongly activated genes was that encoding VBF (At1G56250), an F-box protein that may affect the levels of the VirE2 and VIP1 proteins. Using Arabidopsis cell suspension protoplasts we showed that VirE3 stimulates the VBF promoter, especially when co-expressed with pBrp. Although pBrp is localized at the external surface of plastids, co-expression of VirE3 and pBrp in Arabidopsis cell suspension protoplasts resulted in the accumulation of pBrp in the nucleus. Our results suggest that VirE3 affects the transcriptional machinery of the host cell to favour the transformation process.
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Affiliation(s)
- Xiaolei Niu
- Department of Molecular and Developmental Genetics, Institute of Biology, Leiden University, Sylviusweg 72, 2333BE, Leiden, The Netherlands
| | - Meiliang Zhou
- Department of Molecular and Developmental Genetics, Institute of Biology, Leiden University, Sylviusweg 72, 2333BE, Leiden, The Netherlands
| | - Christiaan V Henkel
- Department of Molecular and Developmental Genetics, Institute of Biology, Leiden University, Sylviusweg 72, 2333BE, Leiden, The Netherlands
| | - G Paul H van Heusden
- Department of Molecular and Developmental Genetics, Institute of Biology, Leiden University, Sylviusweg 72, 2333BE, Leiden, The Netherlands
| | - Paul J J Hooykaas
- Department of Molecular and Developmental Genetics, Institute of Biology, Leiden University, Sylviusweg 72, 2333BE, Leiden, The Netherlands
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25
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Zhou M, Sun Z, Wang C, Zhang X, Tang Y, Zhu X, Shao J, Wu Y. Changing a conserved amino acid in R2R3-MYB transcription repressors results in cytoplasmic accumulation and abolishes their repressive activity in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2015; 84:395-403. [PMID: 26332741 DOI: 10.1111/tpj.13008] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 08/16/2015] [Accepted: 08/20/2015] [Indexed: 05/11/2023]
Abstract
Sub-group 4 R2R3-type MYB transcription factors, including MYB3, MYB4, MYB7 and MYB32, act as repressors in phenylpropanoid metabolism. These proteins contain the conserved MYB domain and the ethylene-responsive element binding factor-associated amphiphilic repression (EAR) repression domain. Additionally, MYB4, MYB7 and MYB32 possess a putative zinc-finger domain and a conserved GY/FDFLGL motif in their C-termini. The protein 'sensitive to ABA and drought 2' (SAD2) recognizes the nuclear pore complex, which then transports the SAD2-MYB4 complex into the nucleus. Here, we show that the conserved GY/FDFLGL motif contributes to the interaction between MYB factors and SAD2. The Asp → Asn mutation in the GY/FDFLGL motif abolishes the interaction between MYB transcription factors and SAD2, and therefore they cannot be transported into the nucleus and cannot repress their target genes. We found that MYB4(D261N) loses the capacity to repress expression of the cinnamate 4-hydroxylase (C4H) gene and biosynthesis of sinapoyl malate. Our results indicate conservation among MYB transcription factors in terms of their interaction with SAD2. Therefore, the Asp → Asn mutation may be used to engineer transcription factors.
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Affiliation(s)
- Meiliang Zhou
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Zhanmin Sun
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Chenglong Wang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
- School of Life Science, Sichuan Agricultural University, Yaan, 625014, Sichuan, China
| | - Xinquan Zhang
- Grassland Science Department, Sichuan Agriculture University, Chengdu, 611130, Sichuan, China
| | - Yixiong Tang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Xuemei Zhu
- School of Resources and Environment, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Jirong Shao
- School of Life Science, Sichuan Agricultural University, Yaan, 625014, Sichuan, China
| | - Yanmin Wu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
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26
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Zarei A, Trobacher CP, Shelp BJ. NAD(+)-aminoaldehyde dehydrogenase candidates for 4-aminobutyrate (GABA) and β-alanine production during terminal oxidation of polyamines in apple fruit. FEBS Lett 2015; 589:2695-700. [PMID: 26296314 DOI: 10.1016/j.febslet.2015.08.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Revised: 08/04/2015] [Accepted: 08/06/2015] [Indexed: 10/23/2022]
Abstract
The last step of polyamine catabolism involves the oxidation of 3-aminopropanal or 4-aminobutanal via aminoaldehyde dehydrogenase. In this study, two apple (Malus x domestica) AMADH genes were selected (MdAMADH1 and MdAMADH2) as candidates for encoding 4-aminobutanal dehydrogenase activity. Maximal activity and catalytic efficiency were obtained with NAD(+) and 3-aminopropanal, followed by 4-aminobutanal, at pH 9.8. NAD(+) reduction was accompanied by the production of GABA and β-alanine, respectively, when 4-aminobutanal and 3-aminopropanal were utilized as substrates. MdAMADH2 was peroxisomal and MdAMADH1 cytosolic. These findings shed light on the potential role of apple AMADHs in 4-aminobutyrate and β-alanine production.
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Affiliation(s)
- Adel Zarei
- Department of Plant Agriculture, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
| | | | - Barry J Shelp
- Department of Plant Agriculture, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
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27
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Zarei A, Trobacher CP, Cooke AR, Meyers AJ, Hall JC, Shelp BJ. Apple fruit copper amine oxidase isoforms: peroxisomal MdAO1 prefers diamines as substrates, whereas extracellular MdAO2 exclusively utilizes monoamines. PLANT & CELL PHYSIOLOGY 2015; 56:137-47. [PMID: 25378687 DOI: 10.1093/pcp/pcu155] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
4-Aminobutyrate (GABA) accumulates in apple fruit during controlled atmosphere storage. A potential source of GABA is the polyamine putrescine, which can be oxidized via copper-containing amine oxidase (CuAO), resulting in the production 4-aminobutanal/Δ(1)-pyrroline, with the consumption of O2 and release of H2O2 and ammonia. Five putative CuAO genes (MdAO genes) were cloned from apple (Malus domestica Borkh. cv. Empire) fruit, and the deduced amino acid sequences found to contain the active sites typically conserved in CuAOs. Genes encoding two of these enzymes, MdAO1 and MdAO2, were highly expressed in apple fruit and selected for further analysis. Amino acid sequence analysis predicted the presence of a C-terminal peroxisomal targeting signal 1 tripeptide in MdAO1 and an N-terminal signal peptide and N-glycosylation site in MdAO2. Transient expression of green fluorescent fusion proteins in Arabidopsis protoplasts or onion epidermal cells revealed a peroxisomal localization for MdAO1 and an extracellular localization for MdAO2. The enzymatic activities of purified recombinant MdAO1 and MdAO2 were measured continuously as H2O2 production using a coupled reaction. MdAO1 did not use monoamines or polyamines and displayed high catalytic efficiency for 1,3-diaminopropane, putrescine and cadaverine, whereas MdAO2 exclusively utilized aliphatic and aromatic monoamines, including 2-phenylethylamine and tyramine. Together, these results indicate that MdAO1 may contribute to GABA production via putrescine oxidation in the peroxisome of apple fruit under controlled atmosphere conditions. MdAO2 seems to be involved in deamination of 2-phenylethylamine, which is a step in the biosynthesis of 2-phenylethanol, a contributor to fruit flavor and flower fragrance.
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Affiliation(s)
- Adel Zarei
- Department of Plant Agriculture, University of Guelph, 50 Stone Road E, Guelph, Canada N1G 2W1
| | - Christopher P Trobacher
- Department of Plant Agriculture, University of Guelph, 50 Stone Road E, Guelph, Canada N1G 2W1
| | - Alison R Cooke
- Department of Plant Agriculture, University of Guelph, 50 Stone Road E, Guelph, Canada N1G 2W1
| | - Ashley J Meyers
- School of Environmental Sciences, University of Guelph, 50 Stone Road E, Guelph, Canada N1G 2W1
| | - J Christopher Hall
- School of Environmental Sciences, University of Guelph, 50 Stone Road E, Guelph, Canada N1G 2W1
| | - Barry J Shelp
- Department of Plant Agriculture, University of Guelph, 50 Stone Road E, Guelph, Canada N1G 2W1
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28
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Bu Y, Zhao M, Sun B, Zhang X, Takano T, Liu S. An efficient method for stable protein targeting in grasses (Poaceae): a case study in Puccinellia tenuiflora. BMC Biotechnol 2014; 14:52. [PMID: 24898217 PMCID: PMC4064272 DOI: 10.1186/1472-6750-14-52] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2014] [Accepted: 05/26/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND An efficient transformation method is lacking for most non-model plant species to test gene function. Therefore, subcellular localization of proteins of interest from non-model plants is mainly carried out through transient transformation in homologous cells or in heterologous cells from model species such as Arabidopsis. Although analysis of expression patterns in model organisms like yeast and Arabidopsis can provide important clues about protein localization, these heterologous systems may not always faithfully reflect the native subcellular distribution in other species. On the other hand, transient expression in protoplasts from species of interest has limited ability for detailed sub-cellular localization analysis (e.g., those involving subcellular fractionation or sectioning and immunodetection), as it results in heterogeneous populations comprised of both transformed and untransformed cells. RESULTS We have developed a simple and reliable method for stable transformation of plant cell suspensions that are suitable for protein subcellular localization analyses in the non-model monocotyledonous plant Puccinellia tenuiflora. Optimization of protocols for obtaining suspension-cultured cells followed by Agrobacterium-mediated genetic transformation allowed us to establish stably transformed cell lines, which could be maintained indefinitely in axenic culture supplied with the proper antibiotic. As a case study, protoplasts of transgenic cell lines stably transformed with an ammonium transporter-green fluorescent protein (PutAMT1;1-GFP) fusion were successfully used for subcellular localization analyses in P. tenuiflora. CONCLUSIONS We present a reliable method for the generation of stably transformed P. tenuiflora cell lines, which, being available in virtually unlimited amounts, can be conveniently used for any type of protein subcellular localization analysis required. Given its simplicity, the method can be used as reference for other non-model plant species lacking efficient regeneration protocols.
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Affiliation(s)
| | | | | | | | | | - Shenkui Liu
- Key Laboratory of Saline-Alkali Vegetation Ecology Restoration in Oil Field (SAVER), Ministry of Education, Alkali Soil Natural Environmental Science Center (ASNESC), Northeast Forestry University, Hexing Road No, 26, Xiangfang District, Harbin City, Heilongjiang Province 150040, China.
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29
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Sakalis PA, van Heusden GPH, Hooykaas PJJ. Visualization of VirE2 protein translocation by the Agrobacterium type IV secretion system into host cells. Microbiologyopen 2014; 3:104-17. [PMID: 24376037 PMCID: PMC3937733 DOI: 10.1002/mbo3.152] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Revised: 11/07/2013] [Accepted: 11/20/2013] [Indexed: 01/28/2023] Open
Abstract
Type IV secretion systems (T4SS) can mediate the translocation of bacterial virulence proteins into host cells. The plant pathogen Agrobacterium tumefaciens uses a T4SS to deliver a VirD2-single stranded DNA complex as well as the virulence proteins VirD5, VirE2, VirE3, and VirF into host cells so that these become genetically transformed. Besides plant cells, yeast and fungi can efficiently be transformed by Agrobacterium. Translocation of virulence proteins by the T4SS has so far only been shown indirectly by genetic approaches. Here we report the direct visualization of VirE2 protein translocation by using bimolecular fluorescence complementation (BiFC) and Split GFP visualization strategies. To this end, we cocultivated Agrobacterium strains expressing VirE2 tagged with one part of a fluorescent protein with host cells expressing the complementary part, either fused to VirE2 (for BiFC) or not (Split GFP). Fluorescent filaments became visible in recipient cells 20-25 h after the start of the cocultivation indicative of VirE2 protein translocation. Evidence was obtained that filament formation was due to the association of VirE2 with the microtubuli.
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Affiliation(s)
- Philippe A Sakalis
- Institute of Biology, Leiden UniversitySylviusweg 72, Leiden, 2333 BE, The Netherlands
| | - G Paul H van Heusden
- Institute of Biology, Leiden UniversitySylviusweg 72, Leiden, 2333 BE, The Netherlands
| | - Paul J J Hooykaas
- Institute of Biology, Leiden UniversitySylviusweg 72, Leiden, 2333 BE, The Netherlands
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30
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Knip M, Hiemstra S, Sietsma A, Castelein M, de Pater S, Hooykaas P. DAYSLEEPER: a nuclear and vesicular-localized protein that is expressed in proliferating tissues. BMC PLANT BIOLOGY 2013; 13:211. [PMID: 24330683 PMCID: PMC4029315 DOI: 10.1186/1471-2229-13-211] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2012] [Accepted: 11/27/2013] [Indexed: 05/08/2023]
Abstract
BACKGROUND DAYSLEEPER is a domesticated transposase that is essential for development in Arabidopsis thaliana [Nature, 436:282-284, 2005]. It is derived from a hAT-superfamily transposon and contains many of the features found in the coding sequence of these elements [Nature, 436:282-284, 2005, Genetics, 158:949-957, 2001]. This work sheds light on the expression of this gene and localization of its product in protoplasts and in planta. Using deletion constructs, important domains in the protein were identified. RESULTS DAYSLEEPER is predominantly expressed in meristems, developing flowers and siliques. The protein is mainly localized in the nucleus, but can also be seen in discrete foci in the cytoplasm. Using several vesicular markers, we found that these foci belong to vesicular structures of the trans-golgi network, multivesicular bodies (MVB's) and late endosomes. The central region as well as both the N- and the C-terminus are essential to DAYSLEEPER function, since versions of DAYSLEEPER deleted for these regions are not able to complement the daysleeper phenotype. Like hAT-transposases, we show that DAYSLEEPER has a functionally conserved dimerization domain [J Biol Chem, 282:7563-7575, 2007]. CONCLUSIONS DAYSLEEPER has retained the global structure of hAT transposases and it seems that most of these conserved features are essential to DAYSLEEPER's cellular function. Although structurally similar, DAYSLEEPER seems to have broadened its range of action beyond the nucleus in comparison to transposases.
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Affiliation(s)
- Marijn Knip
- Department of Molecular and Developmental Genetics, Institute of Biology, Leiden University, Sylviusweg 72, Leiden 2333 BE, The Netherlands
- Current address: Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, Frederiksberg C 1871, Denmark
| | - Steven Hiemstra
- Department of Molecular and Developmental Genetics, Institute of Biology, Leiden University, Sylviusweg 72, Leiden 2333 BE, The Netherlands
- Current address: Department of Toxicology, Leiden/Amsterdam Center for Drug Research, Leiden University, Einsteinweg 55, Leiden 2333 CC, The Netherlands
| | - Afke Sietsma
- Department of Molecular and Developmental Genetics, Institute of Biology, Leiden University, Sylviusweg 72, Leiden 2333 BE, The Netherlands
- Current address: Department of Ecology and Physiology of Plants, Faculty of Earth and Life Sciences, Vrije Universiteit Amsterdam, de Boelelaan 1087, Amsterdam 1081 HV, The Netherlands
| | - Marina Castelein
- Department of Molecular and Developmental Genetics, Institute of Biology, Leiden University, Sylviusweg 72, Leiden 2333 BE, The Netherlands
| | - Sylvia de Pater
- Department of Molecular and Developmental Genetics, Institute of Biology, Leiden University, Sylviusweg 72, Leiden 2333 BE, The Netherlands
| | - Paul Hooykaas
- Department of Molecular and Developmental Genetics, Institute of Biology, Leiden University, Sylviusweg 72, Leiden 2333 BE, The Netherlands
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31
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Jiang F, Zhu J, Liu HL. Protoplasts: a useful research system for plant cell biology, especially dedifferentiation. PROTOPLASMA 2013; 250:1231-8. [PMID: 23719716 DOI: 10.1007/s00709-013-0513-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Accepted: 05/16/2013] [Indexed: 05/03/2023]
Abstract
As protoplasts have the characteristics of no cell walls, rapid population growth, and synchronicity, they are useful tools for research in many fields, especially cellular biology (Table 1). This article is an overview that focuses on the application of protoplasts to investigate the mechanisms of dedifferentiation, including changes in hormone signals, epigenetic changes, and organelle distribution during the dedifferentiation process. The article also emphasizes the wide range of uses for protoplasts in studying protein positions and signaling during different stresses. The examples provided help to show that protoplast systems, for example the mesophyll protoplast system of Arabidopsis, represent promising tools for studying developmental biology. Meanwhile, specific analysis of protoplast, which comes from different tissue, has specific advantages and limitations (Table 2), and it can provide recommendations to use this system.
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Affiliation(s)
- Fangwei Jiang
- School of Life Science and Technology, Tongji University, Shanghai, 200092, China
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Cole M, Jacobs B, Soubigou-Taconnat L, Balzergue S, Renou JP, Chandler JW, Werr W. Live imaging of DORNRÖSCHEN and DORNRÖSCHEN-LIKE promoter activity reveals dynamic changes in cell identity at the microcallus surface of Arabidopsis embryonic suspensions. PLANT CELL REPORTS 2013; 32:45-59. [PMID: 23011125 DOI: 10.1007/s00299-012-1339-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Revised: 08/24/2012] [Accepted: 08/29/2012] [Indexed: 06/01/2023]
Abstract
KEY MESSAGE : Transgenic DRN::erGFP and DRNL::erGFP reporters access the window from explanting Arabidopsis embryos to callus formation and provide evidence for the acquisition of shoot meristem cell fates at the microcalli surface. The DORNRÖSCHEN (DRN) and DORNRÖSCHEN-LIKE (DRNL) genes encode AP2-type transcription factors, which are activated shortly after fertilisation in the zygotic Arabidopsis embryo. We have monitored established transgenic DRN::erGFP and DRNL::erGFP reporter lines using live imaging, for expression in embryonic suspension cultures and our data show that transgenic fluorophore markers are suitable to resolve dynamic changes of cellular identity at the surface of microcalli and enable fluorescence-activated cell sorting. Although DRN::erGFP and DRNL::erGFP are both activated in surface cells, their promoter activity marks different cell identities based on real-time PCR experiments and whole transcriptome microarray data. These transcriptome analyses provide no evidence for the maintenance of embryogenic identity under callus-inducing high-auxin tissue culture conditions but are compatible with the acquisition of shoot meristem cell fates at the surface of suspension calli.
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Affiliation(s)
- M Cole
- Institut für Entwicklungsbiologie, Biozentrum, Universität zu Köln, Zülpicher Str. 47b, 50674, Köln, Germany
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Knip M, de Pater S, Hooykaas PJJ. The SLEEPER genes: a transposase-derived angiosperm-specific gene family. BMC PLANT BIOLOGY 2012; 12:192. [PMID: 23067104 PMCID: PMC3499209 DOI: 10.1186/1471-2229-12-192] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Accepted: 09/22/2012] [Indexed: 05/20/2023]
Abstract
BACKGROUND DAYSLEEPER encodes a domesticated transposase from the hAT-superfamily, which is essential for development in Arabidopsis thaliana. Little is known about the presence of DAYSLEEPER orthologs in other species, or how and when it was domesticated. We studied the presence of DAYSLEEPER orthologs in plants and propose a model for the domestication of the ancestral DAYSLEEPER gene in angiosperms. RESULTS Using specific BLAST searches in genomic and EST libraries, we found that DAYSLEEPER-like genes (hereafter called SLEEPER genes) are unique to angiosperms. Basal angiosperms as well as grasses (Poaceae) and dicotyledonous plants possess such putative orthologous genes, but SLEEPER-family genes were not found in gymnosperms, mosses and algae. Most species contain more than one SLEEPER gene. All SLEEPERs contain a C2H2 type BED-zinc finger domain and a hATC dimerization domain. We designated 3 motifs, partly overlapping the BED-zinc finger and dimerization domain, which are hallmark features in the SLEEPER family. Although SLEEPER genes are structurally conserved between species, constructs with SLEEPER genes from grapevine and rice did not complement the daysleeper phenotype in Arabidopsis, when expressed under control of the DAYSLEEPER promoter. However these constructs did cause a dominant phenotype when expressed in Arabidopsis. Rice plant lines with an insertion in the RICESLEEPER1 or 2 locus displayed phenotypic abnormalities, indicating that these genes are functional and important for normal development in rice. We suggest a model in which we hypothesize that an ancestral hAT transposase was retrocopied and stably integrated in the genome during early angiosperm evolution. Evidence is also presented for more recent retroposition events of SLEEPER genes, such as an event in the rice genome, which gave rise to the RICESLEEPER1 and 2 genes. CONCLUSIONS We propose the ancestral SLEEPER gene was formed after a process of retro-transposition during the evolution of the first angiosperms. It may have acquired an important function early on, as mutation of two SLEEPER genes in rice, like the daysleeper mutant in A. thaliana gave a developmental phenotype indicative of their importance for normal plant development.
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Affiliation(s)
- Marijn Knip
- Department of Molecular and Developmental Genetics, Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands
| | - Sylvia de Pater
- Department of Molecular and Developmental Genetics, Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands
| | - Paul JJ Hooykaas
- Department of Molecular and Developmental Genetics, Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE, Leiden, The Netherlands
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Agrobacterium tumefaciens T-DNA Integration and Gene Targeting in Arabidopsis thaliana Non-Homologous End-Joining Mutants. ACTA ACUST UNITED AC 2012. [DOI: 10.1155/2012/989272] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
In order to study the role of AtKu70 and AtKu80 in Agrobacterium-mediated transformation and gene targeting, plant lines with a T-DNA insertion in AtKu80 or AtKu70 genes were functionally characterized. Such plant lines lacked both subunits, indicating that heterodimer formation between AtKu70 and AtKu80 is needed for the stability of the proteins. Homozygous mutants were phenotypically indistinguishable from wild-type plants and were fertile. However, they were hypersensitive to the genotoxic agent bleomycin, resulting in more DSBs as quantified in comet assays. They had lower end-joining efficiency, suggesting that NHEJ is a critical pathway for DSB repair in plants. Both Atku mutants and a previously isolated Atmre11 mutant were impaired in Agrobacterium T-DNA integration via floral dip transformation, indicating that AtKu70, AtKu80, and AtMre11 play an important role in T-DNA integration in Arabidopsis. The frequency of gene targeting was not significantly increased in the Atku80 and Atku70 mutants, but it was increased at least 10-fold in the Atmre11 mutant compared with the wild type.
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Zarei A, Körbes AP, Younessi P, Montiel G, Champion A, Memelink J. Two GCC boxes and AP2/ERF-domain transcription factor ORA59 in jasmonate/ethylene-mediated activation of the PDF1.2 promoter in Arabidopsis. PLANT MOLECULAR BIOLOGY 2011; 75:321-31. [PMID: 21246258 PMCID: PMC3044237 DOI: 10.1007/s11103-010-9728-y] [Citation(s) in RCA: 147] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2010] [Accepted: 12/27/2010] [Indexed: 05/18/2023]
Abstract
Plant defense against microbial pathogens depends on the action of several endogenously produced hormones, including jasmonic acid (JA) and ethylene (ET). In defense against necrotrophic pathogens, the JA and ET signaling pathways synergize to activate a specific set of defense genes including PLANT DEFENSIN1.2 (PDF1.2). The APETALA2/Ethylene Response Factor (AP2/ERF)-domain transcription factor ORA59 acts as the integrator of the JA and ET signaling pathways and is the key regulator of JA- and ET-responsive PDF1.2 expression. The present study was aimed at the identification of elements in the PDF1.2 promoter conferring the synergistic response to JA/ET and interacting with ORA59. We show that the PDF1.2 promoter was activated synergistically by JA and the ET-releasing agent ethephon due to the activity of two GCC boxes. ORA59 bound in vitro to these GCC boxes and trans-activated the PDF1.2 promoter in transient assays via these two boxes. Using the chromatin immunoprecipitation technique we were able to show that ORA59 bound the PDF1.2 promoter in vivo. Finally, we show that a tetramer of a single GCC box conferred JA/ethephon-responsive expression, demonstrating that the JA and ET signaling pathways converge to a single type of GCC box. Therefore ORA59 and two functionally equivalent GCC box binding sites form the module that enables the PDF1.2 gene to respond synergistically to simultaneous activation of the JA and ET signaling pathways.
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Affiliation(s)
- Adel Zarei
- Institute of Biology, Sylvius Laboratory, Leiden University, P.O. Box 9505, 2300 RA Leiden, The Netherlands
| | - Ana Paula Körbes
- Institute of Biology, Sylvius Laboratory, Leiden University, P.O. Box 9505, 2300 RA Leiden, The Netherlands
| | - Parisa Younessi
- Institute of Biology, Sylvius Laboratory, Leiden University, P.O. Box 9505, 2300 RA Leiden, The Netherlands
| | - Gregory Montiel
- Institute of Biology, Sylvius Laboratory, Leiden University, P.O. Box 9505, 2300 RA Leiden, The Netherlands
- Present Address: Laboratoire de Biologie et Pathologie Végétales, Université de Nantes, BP 92208, 44322 Nantes Cedex 3, France
| | - Antony Champion
- Institute of Biology, Sylvius Laboratory, Leiden University, P.O. Box 9505, 2300 RA Leiden, The Netherlands
- Present Address: Institut de Recherche pour le Développement, UMR Résistance des Plantes aux Bioagresseurs, BP 64501, 34394 Montpellier Cedex 5, France
| | - Johan Memelink
- Institute of Biology, Sylvius Laboratory, Leiden University, P.O. Box 9505, 2300 RA Leiden, The Netherlands
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Montiel G, Zarei A, Körbes AP, Memelink J. The Jasmonate-Responsive Element from the ORCA3 Promoter from Catharanthus roseus is Active in Arabidopsis and is Controlled by the Transcription Factor AtMYC2. ACTA ACUST UNITED AC 2011; 52:578-87. [DOI: 10.1093/pcp/pcr016] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Fusion with fluorescent proteins for subcellular localization of enzymes involved in plant alkaloid biosynthesis. Methods Mol Biol 2010. [PMID: 20552458 DOI: 10.1007/978-1-60761-723-5_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
To establish the role in alkaloid metabolism of candidate genes identified in silico or by Omics approaches, it may be essential to determine the subcellular localization of the encoded proteins. The fusion with fluorescent proteins (FP) may now be used as a quite effective and reliable tool to investigate this question. The methodology involves the choice of the FP, the design and production of the appropriate FP fusions, and the use of a transient or stable transformation protocol applied to a homologous or heterologous plant system. This chapter describes the application of this methodology to an enzyme involved in indole alkaloid biosynthesis, with general considerations on the development of the approach.
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Maraschin FDS, Memelink J, Offringa R. Auxin-induced, SCF(TIR1)-mediated poly-ubiquitination marks AUX/IAA proteins for degradation. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2009; 59:100-9. [PMID: 19309453 DOI: 10.1111/j.1365-313x.2009.03854.x] [Citation(s) in RCA: 128] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The plant hormone auxin (indole-3-acetic acid or IAA) regulates plant development by inducing rapid cellular responses and changes in gene expression. Auxin promotes the degradation of Aux/IAA transcriptional repressors, thereby allowing auxin response factors (ARFs) to activate the transcription of auxin-responsive genes. Auxin enhances the binding of Aux/IAA proteins to the receptor TIR1, which is an F-box protein that is part of the E3 ubiquitin ligase complex SCF(TIR1). Binding of Aux/IAA proteins leads to degradation via the 26S proteasome, but evidence for SCF(TIR1)-mediated poly-ubiquitination of Aux/IAA proteins is lacking. Here we used an Arabidopsis cell suspension-based protoplast system to find evidence for SCF(TIR1)-mediated ubiquitination of the Aux/IAA proteins SHY2/IAA3 and BDL/IAA12. Each of these proteins showed a distinct abundance and repressor activity when expressed in this cell system. Moreover, the amount of endogenous TIR1 protein appeared to be rate-limiting for a proper auxin response measured by the co-transfected DR5::GUS reporter construct. Co-transfection with 35S::TIR1 led to auxin-dependent degradation, and excess of 35S::TIR1 even led to degradation of Aux/IAAs in the absence of auxin treatment. Expression of the mutant tir1-1 protein or the related F-box protein COI1, which is involved in jasmonate signaling, had no effect on Aux/IAA degradation. Our results show that SHY2/IAA3 and BDL/IAA12 are poly-ubiquitinated and degraded in response to increased auxin or TIR1 levels. In conclusion, our data provide experimental support for the model that SCF(TIR1)-dependent poly-ubiquitination of Aux/IAA proteins marks these proteins for degradation by the 26S proteasome, leading to activation of auxin-responsive gene expression.
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Affiliation(s)
- Felipe dos Santos Maraschin
- Institute of Biology, Leiden University, Clusius Laboratorium, Wassenaarseweg 64, 2333 AL Leiden, The Netherlands
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Vert G, Barberon M, Zelazny E, Séguéla M, Briat JF, Curie C. Arabidopsis IRT2 cooperates with the high-affinity iron uptake system to maintain iron homeostasis in root epidermal cells. PLANTA 2009; 229:1171-9. [PMID: 19252923 DOI: 10.1007/s00425-009-0904-8] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2008] [Accepted: 02/06/2009] [Indexed: 05/20/2023]
Abstract
Iron is an essential nutrient for all organisms but toxic when present in excess. Consequently, plants carefully regulate their iron uptake, dependent on the FRO2 ferric reductase and the IRT1 transporter, to control its homeostasis. Arabidopsis IRT2 gene, whose expression is induced in root epidermis upon iron deprivation, was shown to encode a functional iron/zinc transporter in yeast, and proposed to function in iron acquisition from the soil. In this study, we demonstrate that, unlike its close homolog IRT1, IRT2 is not involved in iron absorption from the soil since overexpression of IRT2 does not rescue the iron uptake defect of irt1-1 mutant and since a null irt2 mutant shows no chlorosis in low iron. Consistently, an IRT2-green fluorescent fusion protein, transiently expressed in culture cells, localizes to intracellular vesicles. However, IRT2 appears strictly co-regulated with FRO2 and IRT1, supporting the view that IRT2 is an integral component of the root response to iron deficiency in root epidermal cells. We propose a model where IRT2 likely prevents toxicity from IRT1-dependent iron fluxes in epidermal cells, through compartmentalization.
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Affiliation(s)
- Grégory Vert
- Biochimie et Physiologie Moléculaire des Plantes, Institut de Biologie Intégrative des Plantes, CNRS UMR 5004, 2 place Viala, 34060, Montpellier Cedex 1, France
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40
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Robert HS, Quint A, Brand D, Vivian-Smith A, Offringa R. BTB and TAZ domain scaffold proteins perform a crucial function in Arabidopsis development. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2009; 58:109-21. [PMID: 19054356 DOI: 10.1111/j.1365-313x.2008.03764.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
In Arabidopsis, bric-a-brac, tramtrack and broad (BTB) domain scaffold proteins form a family of 80 proteins that have involvement in various signaling pathways. The five members of the subfamily of BTB AND TAZ DOMAIN proteins (BT1-BT5) have a typical domain structure that is only observed in land plants. Here, we present a functional analysis of the BT family, of which at least four members are encoded by auxin-responsive genes. BT1 is a short-lived protein that is characteristically targeted for degradation by the 26S proteasome. Expression pattern, gene structure and sequence analyses indicate that BT1 and BT2 are closely related. They both localize to the nucleus and the cytosol, whereas the remaining BT proteins were determined as cytosolic proteins. Detailed molecular and phenotypic analysis of plants segregating for null mutations in the BT family revealed substantial redundancy among the BT members, and highlighted that BT proteins perform crucial roles in both male and female gametophyte development. BT2 seems to be the predominant gene in this process, in which it is functionally replaced by BT3 and BT1 through reciprocal transcription regulation. Compensational expression alters the steady-state mRNA levels among the remaining BT family members when other BT members are lost, and this contributes towards functional redundancy. Our data provide a surprising example of functional redundancy among genes required during gametophyte development, something that could not be detected in the current screens for gametophyte mutants.
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MESH Headings
- Arabidopsis/genetics
- Arabidopsis/growth & development
- Arabidopsis/metabolism
- Arabidopsis Proteins/genetics
- Arabidopsis Proteins/metabolism
- Cloning, Molecular
- Cytosol/metabolism
- Gene Expression Regulation, Developmental
- Gene Expression Regulation, Plant
- Genes, Plant
- Germ Cells, Plant/cytology
- Germ Cells, Plant/growth & development
- Germ Cells, Plant/metabolism
- Inbreeding
- Multigene Family
- Multiprotein Complexes/genetics
- Multiprotein Complexes/metabolism
- Mutation
- Phenotype
- Proteasome Endopeptidase Complex/metabolism
- Protein Stability
- Protoplasts/cytology
- Protoplasts/metabolism
- RNA, Messenger/analysis
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Plant/genetics
- RNA, Plant/metabolism
- Seeds/genetics
- Seeds/growth & development
- Seeds/metabolism
- Species Specificity
- Transcription Factors/genetics
- Transcription Factors/metabolism
- Transcription, Genetic
- Transfection
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Affiliation(s)
- Hélène S Robert
- Department of Molecular and Developmental Genetics, Institute of Biology, Leiden University, Wassenaarseweg 64, 2333 AL Leiden, The Netherlands
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41
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Kohorn BD, Kobayashi M, Johansen S, Friedman HP, Fischer A, Byers N. Wall-associated kinase 1 (WAK1) is crosslinked in endomembranes, and transport to the cell surface requires correct cell-wall synthesis. J Cell Sci 2007; 119:2282-90. [PMID: 16723734 DOI: 10.1242/jcs.02968] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Arabidopsis thaliana wall-associated kinases (WAKs) bind to pectin with an extracellular domain and also contain a cytoplasmic protein kinase domain. WAKs are required for cell elongation and modulate sugar metabolism. This work shows that in leaf protoplasts a WAK1-GFP fusion protein accumulates in a cytoplasmic compartment that contains pectin. The WAK compartment contains markers for the Golgi, the site of pectin synthesis. The migration of WAK1-GFP to the cell surface is far slower than that of a cell surface receptor not associated with the cell wall, is influenced by the presence of fucose side chains on one or more unidentified molecules that might include pectin, and is dependent upon cellulose synthesis on the plasma membrane. WAK is crosslinked into a detergent-insoluble complex within the cytoplasmic compartment before it appears on the cell surface, and this is independent of fucose modification or cellulose synthesis. Thus, the assembly and crosslinking of WAKs may begin at an early stage within a cytoplasmic compartment rather than in the cell wall itself, and is coordinated with synthesis of surface cellulose.
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Affiliation(s)
- Bruce D Kohorn
- Department of Biology, Bowdoin College, Brunswick, ME 04011, USA.
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42
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Raghupathy MB, Griffiths JS, Stobbs LW, Brown DCW, Brandle JE, Wang A. Transfection of Arabidopsis protoplasts with a Plum pox virus (PPV) infectious clone for studying early molecular events associated with PPV infection. J Virol Methods 2006; 136:147-53. [PMID: 16777241 DOI: 10.1016/j.jviromet.2006.05.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2006] [Revised: 04/18/2006] [Accepted: 05/02/2006] [Indexed: 10/24/2022]
Abstract
The development of novel strategies against plant viral diseases relies on a better understanding of molecular virus-host interactions. Here, we report an easy, efficient and reproducible protocol for Arabidopsis protoplast isolation and transfection to study the infection and replication of a potyvirus, Plum pox virus (PPV). Macerozyme and cellulose were used to release protoplasts from Arabidopsis leaf tissues, and polyethylene glycol-mediated DNA uptake was employed for transfection of a PPV infectious clone. Protoplast viability was monitored by fluorescein diacetate staining, and transfection efficiency was estimated by transient expression of the green fluorescent protein. The protocol allowed production of 95% viable mesophyll protoplasts and a successful transfection rate of 35%. The system was used further in a time-course experiment to investigate PPV viral RNA accumulation. It was found that 3 h post-transfection (hpt) in the transfected protoplasts viral RNA increased by about 150-fold and progressively accumulated to reach the maximum at 12 hpt. Viral RNA then decreased dramatically at 24 hpt reaching 40% of its peak level. Considering the availability of the whole genome microarrays, and other genomic resources of Arabidopsis, the synchronized single-cell (protoplast) infection system will be useful for elucidating early molecular events associated with PPV infection.
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Affiliation(s)
- Mohan B Raghupathy
- Southern Crop Protection and Food Research Centre, Agriculture and Agri-Food Canada, 1391 Sandford St., London, Ontario, Canada N5V 4T3
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Kwon HK, Yokoyama R, Nishitani K. A proteomic approach to apoplastic proteins involved in cell wall regeneration in protoplasts of Arabidopsis suspension-cultured cells. PLANT & CELL PHYSIOLOGY 2005; 46:843-57. [PMID: 15769804 DOI: 10.1093/pcp/pci089] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
To clarify the mechanisms of cell wall construction, we used a proteomic approach to investigate the proteins secreted into cell wall spaces during cell wall regeneration from the protoplasts of Arabidopsis suspension-cultured cells. We focused on cell wall proteins loosely bound to the cell wall architecture and extractable with 1 M KCl solutions from: (i) native suspension cultured cells; (ii) protoplasts that had been allowed to regenerate their cell walls for 1 h; and (iii) protoplasts allowed to regenerate their cell walls for 3 h. We adopted a non-destructive extraction procedure without disrupting cellular integrity, thereby avoiding contamination from cytoplasmic proteins. Using two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) and matrix-assisted laser desorption ionization-time-of-flight/mass spectrometry (MALDI-TOF/MS), we separated, mapped and identified 71 proteins derived from the native cell wall, and 175 and 212 proteins derived from the 1 and 3 h regenerated protoplasts, respectively. Quite different sets of proteins with differing status of their post-translational modifications, including phosphorylation and glycosylation, were identified in the three protein fractions. This indicated dynamic in muro changes in the cell wall proteins during cell wall regeneration in the protoplasts. The analysis revealed a set of enzymes specifically involved in cell wall expansion and construction in suspension-cultured cells. This approach has also determined a set of cell wall proteins that had not been predicted to be localized in cell wall spaces.
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Affiliation(s)
- Hye-Kyoung Kwon
- Department of Developmental Biology and Neurosciences, Graduate School of Life Sciences, Tohoku University, Sendai, 980-8578 Japan
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Bink HHJ, Roepan SK, Pleij CWA. Two histidines of the coat protein of turnip yellow mosaic virus at the capsid interior are crucial for viability. Proteins 2004; 55:236-44. [PMID: 15048817 DOI: 10.1002/prot.10600] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
RNA-coat protein interactions in turnip yellow mosaic virus (TYMV) have been shown to involve low pK proton-donating groups. Two different types of interaction have been proposed. In the so-called type I interaction, protonated C-residues interact with acidic amino acids at low pH, thereby providing a rationale for the high C-content (38%) of the genomic RNA. The type II interaction involves charged histidines interacting with phosphates of the RNA backbone. Site-directed mutagenesis of the TYMV coat protein and subsequent in vivo analysis were performed to distinguish between these two types of RNA-protein interaction. The results reveal a prominent role for the histidines H68 and H180, since mutation to an alanine residue inhibits symptom development on secondary leaves, indicating that spreading of the virus in the plant is blocked. Viral RNA and coat protein synthesis are not altered, showing that these two histidines may play a role in the process of RNA encapsidation. Overexpression of the TYMV coat protein in Escherichia coli leads to the formation of bona fide capsids, showing that the two histidines are not critical in capsid assembly. Mutagenesis of the acidic amino acids D11, E135, and D143 to alanine apparently did not interfere with virus viability. The functional role of the histidines during the infection cycle is discussed in terms of the structure of the coat protein, both at the level of amino acid sequence conservation among the members of the Tymoviridae family and as the three-dimensional structure of the coat protein.
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Affiliation(s)
- Hugo H J Bink
- Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, Leiden, The Netherlands
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Bink HHJ, Schirawski J, Haenni AL, Pleij CWA. The 5'-proximal hairpin of turnip yellow mosaic virus RNA: its role in translation and encapsidation. J Virol 2003; 77:7452-8. [PMID: 12805444 PMCID: PMC164824 DOI: 10.1128/jvi.77.13.7452-7458.2003] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The RNA genome of turnip yellow mosaic virus (TYMV) consists of more than 6,000 nucleotides. During a study of the roles of the two hairpins located in its 90-nucleotide 5' untranslated region, it was observed that stabilization of the 5'-proximal hairpin leads to a delay in the development of symptoms on plants. This delay in symptom development for both locally and systemically infected leaves was found to be dependent on a change in the free energy of the hairpin caused by introduced mutations. A protoplast transfection assay revealed that the accumulation of plus-strand full-length RNA and subgenomic RNA, as well as protein expression levels, was affected by hairpin stability. Stabilization of this hairpin inhibited translation. A model is proposed in which a destabilized 5'-proximal hairpin allows maximal translation of the viral proteins. It is suggested that this hairpin may exist in close proximity to the 5' cap as long as its stability is low enough to enable translation. However, at an acidic pH, the hairpin structure becomes more stable and is functionally transformed into the initiation signal for viral packaging. Slightly acidic conditions can be found in chloroplasts, where TYMV assembly is driven by a low pH generated by active photosynthesis.
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Affiliation(s)
- Hugo H J Bink
- Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands
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46
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Prod'homme D, Le Panse S, Drugeon G, Jupin I. Detection and subcellular localization of the turnip yellow mosaic virus 66K replication protein in infected cells. Virology 2001; 281:88-101. [PMID: 11222099 DOI: 10.1006/viro.2000.0769] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Turnip yellow mosaic virus (TYMV) encodes a 206-kDa (206K) polyprotein with domains of methyltransferase, proteinase, NTPase/helicase, and RNA-dependent RNA polymerase (RdRp). In vitro, the 206K protein has been shown to undergo proteolytic processing, giving rise to the synthesis of 140-kDa (140K) and 66-kDa (66K) proteins, the latter comprising the RdRp protein domain. Antibodies were raised against the 66K protein and were used to detect the corresponding viral protein in infected cells; both leaf tissues and protoplasts were examined. The antiserum specifically recognized a protein of approximately 66 kDa, indicating that the cleavage observed in vitro is also functional in vivo. The 66K protein accumulates transiently during protoplast infection and localizes to cellular membrane fractions. Indirect immunofluorescence assays and electron microscopy of immunogold-decorated ultrathin sections of infected leaf tissue using anti-66K-specific antibody revealed labeling of membrane vesicles located at the chloroplast envelope.
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Affiliation(s)
- D Prod'homme
- Laboratoire de Virologie Moléculaire, Institut Jacques Monod, UMR 7592, CNRS, Universités Paris 6-Paris 7, 2 place Jussieu, 75251 Paris Cedex 05, France
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Schirawski J, Voyatzakis A, Zaccomer B, Bernardi F, Haenni AL. Identification and functional analysis of the turnip yellow mosaic tymovirus subgenomic promoter. J Virol 2000; 74:11073-80. [PMID: 11070002 PMCID: PMC113187 DOI: 10.1128/jvi.74.23.11073-11080.2000] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Most plant viruses rely on the production of subgenomic RNAs (sgRNAs) for the expression of their genes and survival in the plant. Although this is a widely adopted strategy among viruses, the mechanism(s) whereby sgRNA production occurs remains poorly defined. Turnip yellow mosaic tymovirus (TYMV) is a positive-stranded RNA virus that produces an sgRNA for the expression of its coat protein. Here we report that the subgenomic promoter sequence of TYMV is located on a 494-nucleotide fragment, containing previously identified highly conserved sequence elements, which are shown here to be essential for promoter function. After duplication, the subgenomic promoter can be inserted into the coat protein open reading frame, giving rise to the in vivo production of a second sgRNA. It is suggested that this promoter can function when contained on a different molecule than viral genomic RNA. This interesting trait may be of general use for plant and plant virus research.
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Affiliation(s)
- J Schirawski
- Institut Jacques Monod, 75251 Paris Cedex 05, France.
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