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Li Q, Wang G, Guan C, Yang D, Wang Y, Zhang Y, Ji J, Jin C, An T. Overexpression of LcSABP, an Orthologous Gene for Salicylic Acid Binding Protein 2, Enhances Drought Stress Tolerance in Transgenic Tobacco. FRONTIERS IN PLANT SCIENCE 2019; 10:200. [PMID: 30847000 PMCID: PMC6393331 DOI: 10.3389/fpls.2019.00200] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Accepted: 02/06/2019] [Indexed: 05/26/2023]
Abstract
Salicylic acid (SA) plays an essential role in the growth and development of plants, and in their response to abiotic stress. Previous studies have mostly focused on the effects of exogenously applied SA on the physiological response of plants to abiotic stresses; however, the underlying genetic mechanisms for the regulatory functions of endogenous SA in the defense response of plants remain unclear. In plants, SA binding protein 2 (SABP2), possessing methyl salicylate (MeSA) esterase activity, catalyzes the conversion of MeSA to SA. Herein, a SABP2-like gene, LcSABP, was cloned from Lycium chinense, which contained a complete open reading frame of 795 bp and encoded a protein of 264 amino acids that shared high sequence similarities with SABP2 orthologs from other plants. Overexpression of LcSABP enhanced the drought tolerance of transgenic tobacco plants. The results indicated that increased levels of LcSABP transcripts and endogenous SA content were involved in the enhanced drought tolerance. Physiological and biochemical studies further demonstrated that higher chlorophyll content, increased photosynthetic capacity, lower malondialdehyde content, and higher activities of superoxide dismutase, peroxidase, and catalase enhanced the drought tolerance of transgenic plants. Moreover, overexpression of LcSABP also increased the expression of reactive oxygen species (ROS)- and stress-responsive genes under drought stress. Overall, our results demonstrate that LcSABP plays a positive regulatory role in drought stress response by enhancing the endogenous SA content, promoting the scavenging of ROS, and regulating of the expression of stress-related transcription factor genes. Our findings indicate that LcSABP functions as a major regulator of the plant's response to drought stress through a SA-dependent defense pathway.
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Affiliation(s)
- Qian Li
- School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Gang Wang
- School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Chunfeng Guan
- School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Dan Yang
- School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Yurong Wang
- Division of Biological Sciences, University of California, San Diego, San Diego, CA, United States
| | - Yue Zhang
- School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Jing Ji
- School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Chao Jin
- School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Ting An
- School of Environmental Science and Engineering, Tianjin University, Tianjin, China
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Srivastava A, Zode SS, Pandey J, Srivastava K, Tandon P, Ayala AP, Bansal AK. A novel approach to design febuxostat-salicylic acid eutectic system: evaluation and characterization. CrystEngComm 2019. [DOI: 10.1039/c8ce01212a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The current study was aimed at investigating the febuxostat-salicylic acid (FXT-SAA) eutectic system using two polymorphs of FXT, form Q and form A.
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Affiliation(s)
| | - Sandeep S. Zode
- Department of Pharmaceutics
- National Institute of Pharmaceutical Education and Research (NIPER)
- S. A. S. Nagar
- India
| | - Jaya Pandey
- Department of Physics
- University of Lucknow
- Lucknow 226 007
- India
| | | | - Poonam Tandon
- Department of Physics
- University of Lucknow
- Lucknow 226 007
- India
| | - Alejandro P. Ayala
- Departamento de Física
- Universidade Federal do Ceará
- 60.455-900 Fortaleza
- Brazil
| | - Arvind K. Bansal
- Department of Pharmaceutics
- National Institute of Pharmaceutical Education and Research (NIPER)
- S. A. S. Nagar
- India
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53
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Chen J, Wang J, Chen W, Sun W, Peng M, Yuan Z, Shen S, Xie K, Jin C, Sun Y, Liu X, Fernie AR, Yu S, Luo J. Metabolome Analysis of Multi-Connected Biparental Chromosome Segment Substitution Line Populations. PLANT PHYSIOLOGY 2018; 178:612-625. [PMID: 30139795 PMCID: PMC6181037 DOI: 10.1104/pp.18.00490] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 08/14/2018] [Indexed: 05/05/2023]
Abstract
Metabolomic analysis coupled with advanced genetic populations represents a powerful tool with which to investigate the plant metabolome. However, genetic analyses of the rice (Oryza sativa) metabolome have been conducted mainly using natural accessions or a single biparental population. Here, the flag leaves from three interconnected chromosome segment substitution line populations with a common recurrent genetic background were used to dissect rice metabolic diversity. We effectively used multiple interconnected biparental populations, constructed by introducing genomic segments into Zhenshan 97 from ACC10 (A/Z), Minghui 63 (M/Z), and Nipponbare (N/Z), to map metabolic quantitative trait loci (mQTL). A total of 1,587 mQTL were generated, of which 684, 479, and 722 were obtained from the A/Z, M/Z, and N/Z chromosome segment substitution line populations, respectively, and we designated 99 candidate genes for 367 mQTL. In addition, 1,001 mQTL were generated specifically from joint linkage analysis with 25 candidate genes assigned. Several of these candidates were validated, such as LOC_Os07g01020 for the in vivo content of pyridoxine and its derivative and LOC_Os04g25980 for cis-zeatin glucosyltransferase activity. We propose a novel biosynthetic pathway for O-methylapigenin C-pentoside and demonstrated that LOC_Os04g11970 encodes a component of this pathway through fine-mapping. We postulate that the methylated apigenin may confer plant disease resistance. This study demonstrates the power of using multiple interconnected populations to generate a large number of veritable mQTL. The combined results are discussed in the context of functional metabolomics and the possible features of assigned candidates underlying respective metabolites.
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Affiliation(s)
- Jie Chen
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Jilin Wang
- Rice Research Institute, Jiangxi Academy of Agricultural Sciences, Nanchang 330200, China
| | - Wei Chen
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Wenqiang Sun
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Meng Peng
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China
| | - Zhiyang Yuan
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Shuangqian Shen
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China
| | - Kun Xie
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Cheng Jin
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China
| | - Yangyang Sun
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China
| | - Xianqing Liu
- College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Alisdair R Fernie
- Max-Planck-Institute of Molecular Plant Physiology, Potsdam-Golm 144776, Germany
- Center of Plant System Biology and Biotechnology, Plovdiv 4000, Bulgaria
| | - Sibin Yu
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Jie Luo
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China
- Institute of Tropical Agriculture and Forestry of Hainan University, Haikou, Hainan 572208, China
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Klessig DF, Choi HW, Dempsey DA. Systemic Acquired Resistance and Salicylic Acid: Past, Present, and Future. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2018; 31:871-888. [PMID: 29781762 DOI: 10.1094/mpmi-03-18-0067-cr] [Citation(s) in RCA: 233] [Impact Index Per Article: 38.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
This article is part of the Distinguished Review Article Series in Conceptual and Methodological Breakthroughs in Molecular Plant-Microbe Interactions. Salicylic acid (SA) is a critical plant hormone that regulates numerous aspects of plant growth and development as well as the activation of defenses against biotic and abiotic stress. Here, we present a historical overview of the progress that has been made to date in elucidating the role of SA in signaling plant immune responses. The ability of plants to develop acquired immunity after pathogen infection was first proposed in 1933. However, most of our knowledge about plant immune signaling was generated over the last three decades, following the discovery that SA is an endogenous defense signal. During this timeframe, researchers have identified i) two pathways through which SA can be synthesized, ii) numerous proteins that regulate SA synthesis and metabolism, and iii) some of the signaling components that function downstream of SA, including a large number of SA targets or receptors. In addition, it has become increasingly evident that SA does not signal immune responses by itself but, rather, as part of an intricate network that involves many other plant hormones. Future efforts to develop a comprehensive understanding of SA-mediated immune signaling will therefore need to close knowledge gaps that exist within the SA pathway itself as well as clarify how crosstalk among the different hormone signaling pathways leads to an immune response that is both robust and optimized for maximal efficacy, depending on the identity of the attacking pathogen.
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Affiliation(s)
| | - Hyong Woo Choi
- Boyce Thompson Institute, 533 Tower Rd, Ithaca, NY 14853, U.S.A
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Grosse‐Holz F, Kelly S, Blaskowski S, Kaschani F, Kaiser M, van der Hoorn RA. The transcriptome, extracellular proteome and active secretome of agroinfiltrated Nicotiana benthamiana uncover a large, diverse protease repertoire. PLANT BIOTECHNOLOGY JOURNAL 2018; 16:1068-1084. [PMID: 29055088 PMCID: PMC5902771 DOI: 10.1111/pbi.12852] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 10/06/2017] [Accepted: 10/15/2017] [Indexed: 05/06/2023]
Abstract
Infiltration of disarmed Agrobacterium tumefaciens into leaves of Nicotiana benthamiana (agroinfiltration) facilitates quick and safe production of antibodies, vaccines, enzymes and metabolites for industrial use (molecular farming). However, yield and purity of proteins produced by agroinfiltration are hampered by unintended proteolysis, restricting industrial viability of the agroinfiltration platform. Proteolysis may be linked to an immune response to agroinfiltration, but understanding of the response to agroinfiltration is limited. To identify the proteases, we studied the transcriptome, extracellular proteome and active secretome of agroinfiltrated leaves over a time course, with and without the P19 silencing inhibitor. Remarkably, the P19 expression had little effect on the leaf transcriptome and no effect on the extracellular proteome. 25% of the detected transcripts changed in abundance upon agroinfiltration, associated with a gradual up-regulation of immunity at the expense of photosynthesis. By contrast, 70% of the extracellular proteins increased in abundance, in many cases associated with increased efficiency of extracellular delivery. We detect a dynamic reprogramming of the proteolytic machinery upon agroinfiltration by detecting transcripts encoding for 975 different proteases and protease homologs. The extracellular proteome contains peptides derived from 196 proteases and protease homologs, and activity-based proteomics displayed 17 active extracellular Ser and Cys proteases in agroinfiltrated leaves. We discuss unique features of the N. benthamiana protease repertoire and highlight abundant extracellular proteases in agroinfiltrated leaves, being targets for reverse genetics. This data set increases our understanding of the plant response to agroinfiltration and indicates ways to improve a key expression platform for both plant science and molecular farming.
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Affiliation(s)
| | - Steven Kelly
- Department of Plant SciencesUniversity of OxfordOxfordUK
| | - Svenja Blaskowski
- Chemische BiologieZentrum für Medizinische BiotechnologieFakultät für BiologieUniversität Duisburg‐EssenEssenGermany
| | - Farnusch Kaschani
- Chemische BiologieZentrum für Medizinische BiotechnologieFakultät für BiologieUniversität Duisburg‐EssenEssenGermany
| | - Markus Kaiser
- Chemische BiologieZentrum für Medizinische BiotechnologieFakultät für BiologieUniversität Duisburg‐EssenEssenGermany
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56
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Carbohydrates, volatile and phenolic compounds composition, and antioxidant activity of calabura (Muntingia calabura L.) fruit. Food Res Int 2018; 108:264-273. [PMID: 29735056 DOI: 10.1016/j.foodres.2018.03.046] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 03/13/2018] [Accepted: 03/15/2018] [Indexed: 12/24/2022]
Abstract
Soluble carbohydrates, volatile and phenolic compounds from calabura fruit as well as its antioxidant activity were assessed. The low amount of fermentable oligo-, di-, and monosaccharides and polyols (FODMAPs) and similar amount of glucose and fructose allow us to classify the calabura berry as low-FODMAPs. The terpenes β-Farnesene and dendrolasin identified by SPME-GC-MS were the major volatile components. UHPLC-MS/MS analysis revelled gallic acid (5325 μg/g dw) and cyanidin-3-O-glucoside (171 μg/g dw) as the main phenolic compounds, followed by gentisic acid, gallocatechin, caffeic acid and protocatechuic acid. In addition, gallic acid was found mainly in esterified (2883 μg/g dw) and insoluble-bound (2272 μg/g dw) forms. Free and glycosylated forms showed however the highest antioxidant activity due to occurrence of flavonoids (0.28-27 μg/g dw) in these fractions, such as catechin, gallocatechin, epigallocatechin, naringenin, and quercetin. These findings clearly suggest that calabura is a berry with low energy value and attractive colour and flavour that may contribute to the intake of several bioactive compounds with antioxidant activity. Furthermore, this berry have great potential for use in the food industry and as functional food.
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57
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Poque S, Wu HW, Huang CH, Cheng HW, Hu WC, Yang JY, Wang D, Yeh SD. Potyviral Gene-Silencing Suppressor HCPro Interacts with Salicylic Acid (SA)-Binding Protein 3 to Weaken SA-Mediated Defense Responses. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2018; 31:86-100. [PMID: 29090655 DOI: 10.1094/mpmi-06-17-0128-fi] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
The viral infection process is a battle between host defense response and pathogen antagonizing action. Several studies have established a tight link between the viral RNA silencing suppressor (RSS) and the repression of salicylic acid (SA)-mediated defense responses, nonetheless host factors directly linking an RSS and the SA pathway remains unidentified. From yeast two-hybrid analysis, we identified an interaction between the potyviral RSS helper-component proteinase (HCPro) and SA-binding protein SABP3. Co-localization and bimolecular fluorescence complementation analyses validated the direct in vivo interaction between Turnip mosaic virus (TuMV) HCPro and the Arabidopsis homologue of SABP3, AtCA1. Additionally, transient expression of TuMV HCPro demonstrated its ability to act as a negative regulator of AtCA1. When the plants of the AtCA1 knockout mutant line were inoculated with TuMV, our results indicated that AtCA1 is essential to restrict viral spreading and accumulation, induce SA accumulation, and trigger the SA pathway. Unexpectedly, the AtCA1 overexpression line also displayed a similar phenotype, suggesting that the constitutive expression of AtCA1 antagonizes the SA pathway. Taken together, our results depict AtCA1 as an essential regulator of SA defense responses. Moreover, the interaction of potyviral HCPro with this regulator compromises the SA pathway to weaken host defense responses and facilitate viral infection.
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Affiliation(s)
- Sylvain Poque
- 1 Department of Plant Pathology, National Chung-Hsing University, Taichung City 40227, Taiwan, R.O.C
| | - Hui-Wen Wu
- 2 Agricultural Biotechnology Center, National Chung-Hsing University
| | - Chung-Hao Huang
- 1 Department of Plant Pathology, National Chung-Hsing University, Taichung City 40227, Taiwan, R.O.C
| | - Hao-Wen Cheng
- 3 NCHU-UCD Plant and Food Biotechnology Center, National Chung-Hsing University
| | - Wen-Chi Hu
- 3 NCHU-UCD Plant and Food Biotechnology Center, National Chung-Hsing University
| | - Jun-Yi Yang
- 4 Institute of Biochemistry, National Chung-Hsing University; and
| | - David Wang
- 5 Department of Forestry, National Chung-Hsing University
| | - Shyi-Dong Yeh
- 1 Department of Plant Pathology, National Chung-Hsing University, Taichung City 40227, Taiwan, R.O.C
- 2 Agricultural Biotechnology Center, National Chung-Hsing University
- 3 NCHU-UCD Plant and Food Biotechnology Center, National Chung-Hsing University
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58
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Jones BJ, Lim HY, Huang J, Kazlauskas RJ. Comparison of Five Protein Engineering Strategies for Stabilizing an α/β-Hydrolase. Biochemistry 2017; 56:6521-6532. [PMID: 29087185 DOI: 10.1021/acs.biochem.7b00571] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A review of the previous stabilization of α/β-hydrolase fold enzymes revealed many different strategies, but no comparison of strategies on the same enzyme. For this reason, we compared five strategies to identify stabilizing mutations in a model α/β-hydrolase fold enzyme, salicylic acid binding protein 2, to reversible denaturation by urea and to irreversible denaturation by heat. The five strategies included one location agnostic approach (random mutagenesis using error-prone polymerase chain reaction), two structure-based approaches [computational design (Rosetta, FoldX) and mutation of flexible regions], and two sequence-based approaches (addition of proline at locations where a more stable homologue has proline and mutation to consensus). All strategies identified stabilizing mutations, but the best balance of success rate, degree of stabilization, and ease of implementation was mutation to consensus. A web-based automated program that predicts substitutions needed to mutate to consensus is available at http://kazlab.umn.edu .
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Affiliation(s)
- Bryan J Jones
- Department of Biochemistry, Molecular Biology & Biophysics and The Biotechnology Institute, University of Minnesota , 1479 Gortner Avenue, Saint Paul, Minnesota 55108, United States
| | - Huey Yee Lim
- Department of Biochemistry, Molecular Biology & Biophysics and The Biotechnology Institute, University of Minnesota , 1479 Gortner Avenue, Saint Paul, Minnesota 55108, United States
| | - Jun Huang
- Department of Biochemistry, Molecular Biology & Biophysics and The Biotechnology Institute, University of Minnesota , 1479 Gortner Avenue, Saint Paul, Minnesota 55108, United States.,School of Biological and Chemical Engineering, Zhejiang University of Science and Technology , Hangzhou 310023, People's Republic of China
| | - Romas J Kazlauskas
- Department of Biochemistry, Molecular Biology & Biophysics and The Biotechnology Institute, University of Minnesota , 1479 Gortner Avenue, Saint Paul, Minnesota 55108, United States
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59
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Dimitriou PS, Denesyuk A, Takahashi S, Yamashita S, Johnson MS, Nakayama T, Denessiouk K. Alpha/beta-hydrolases: A unique structural motif coordinates catalytic acid residue in 40 protein fold families. Proteins 2017. [DOI: 10.1002/prot.25338] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Polytimi S. Dimitriou
- Structural Bioinformatics Laboratory, Biochemistry, Faculty of Science and Engineering; Åbo Akademi University; Turku 20520 Finland
| | - Alexander Denesyuk
- Structural Bioinformatics Laboratory, Biochemistry, Faculty of Science and Engineering; Åbo Akademi University; Turku 20520 Finland
- Institute for Biological Instrumentation of the Russian Academy of Sciences; Pushchino 142290 Russia
| | - Seiji Takahashi
- Department of Biomolecular Engineering, Graduate School of Engineering; Tohoku University; Sendai Miyagi 980-8579 Japan
| | - Satoshi Yamashita
- Division of Material Chemistry, Graduate School of Natural Science and Technology; Kanazawa University; Kanazawa Ishikawa 920-1192 Japan
| | - Mark S. Johnson
- Structural Bioinformatics Laboratory, Biochemistry, Faculty of Science and Engineering; Åbo Akademi University; Turku 20520 Finland
| | - Toru Nakayama
- Department of Biomolecular Engineering, Graduate School of Engineering; Tohoku University; Sendai Miyagi 980-8579 Japan
| | - Konstantin Denessiouk
- Structural Bioinformatics Laboratory, Biochemistry, Faculty of Science and Engineering; Åbo Akademi University; Turku 20520 Finland
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Dhandapani S, Jin J, Sridhar V, Sarojam R, Chua NH, Jang IC. Integrated metabolome and transcriptome analysis of Magnolia champaca identifies biosynthetic pathways for floral volatile organic compounds. BMC Genomics 2017; 18:463. [PMID: 28615048 PMCID: PMC5471912 DOI: 10.1186/s12864-017-3846-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 06/06/2017] [Indexed: 12/02/2022] Open
Abstract
Background Magnolia champaca, commonly known as champak is a well-known tree due to its highly fragrant flowers. Champak floral scent is attributed to a complex mix of volatile organic compounds (VOCs). These aromatic flowers are widely used in flavors and fragrances industry. Despite its commercial importance, the VOC biosynthesis pathways in these flowers are largely unknown. Here, we combine metabolite and RNA sequencing (RNA-seq) analyses of fully opened champak flowers to discover the active VOC biosynthesis pathways as well as floral scent-related genes. Results Volatile collection by headspace method and analysis by gas chromatography-mass spectrometry (GC-MS) identified a total of 43 VOCs from fully opened champak flowers, of which 46.9% were terpenoids, 38.9% were volatile esters and 5.2% belonged to phenylpropanoids/benzenoids. Sequencing and de novo assembly of champak flower transcriptome yielded 47,688 non-redundant unigenes. Transcriptome assembly was validated using standard polymerase chain reaction (PCR) based approach for randomly selected unigenes. The detailed profiles of VOCs led to the discovery of pathways and genes involved in floral scent biosynthesis from RNA-seq data. Analysis of expression levels of many floral-scent biosynthesis-related unigenes in flowers and leaves showed that most of them were expressed higher in flowers than in leaf tissues. Moreover, our metabolite-guided transcriptomics, in vitro and in vivo enzyme assays and transgenic studies identified (R)-linalool synthase that is essential for the production of major VOCs of champak flowers, (R)-linalool and linalool oxides. Conclusion As our study is the first report on transcriptome analysis of Magnolia champaca, this transcriptome dataset that serves as an important public information for functional genomics will not only facilitate better understanding of ecological functions of champak floral VOCs, but also provide biotechnological targets for sustainable production of champak floral scent. Electronic supplementary material The online version of this article (doi:10.1186/s12864-017-3846-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Savitha Dhandapani
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, 117604, Singapore.,Department of Biological Sciences, National University of Singapore, Singapore, 117543, Singapore
| | - Jingjing Jin
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, 117604, Singapore
| | - Vishweshwaran Sridhar
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, 117604, Singapore
| | - Rajani Sarojam
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, 117604, Singapore
| | - Nam-Hai Chua
- Laboratory of Plant Molecular Biology, The Rockefeller University, 1230 York Avenue, New York, NY, 10065, USA
| | - In-Cheol Jang
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, 117604, Singapore. .,Department of Biological Sciences, National University of Singapore, Singapore, 117543, Singapore.
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61
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Belt K, Huang S, Thatcher LF, Casarotto H, Singh KB, Van Aken O, Millar AH. Salicylic Acid-Dependent Plant Stress Signaling via Mitochondrial Succinate Dehydrogenase. PLANT PHYSIOLOGY 2017; 173:2029-2040. [PMID: 28209841 PMCID: PMC5373042 DOI: 10.1104/pp.16.00060] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 02/14/2017] [Indexed: 05/19/2023]
Abstract
Mitochondria are known for their role in ATP production and generation of reactive oxygen species, but little is known about the mechanism of their early involvement in plant stress signaling. The role of mitochondrial succinate dehydrogenase (SDH) in salicylic acid (SA) signaling was analyzed using two mutants: disrupted in stress response1 (dsr1), which is a point mutation in SDH1 identified in a loss of SA signaling screen, and a knockdown mutant (sdhaf2) for SDH assembly factor 2 that is required for FAD insertion into SDH1. Both mutants showed strongly decreased SA-inducible stress promoter responses and low SDH maximum capacity compared to wild type, while dsr1 also showed low succinate affinity, low catalytic efficiency, and increased resistance to SDH competitive inhibitors. The SA-induced promoter responses could be partially rescued in sdhaf2, but not in dsr1, by supplementing the plant growth media with succinate. Kinetic characterization showed that low concentrations of either SA or ubiquinone binding site inhibitors increased SDH activity and induced mitochondrial H2O2 production. Both dsr1 and sdhaf2 showed lower rates of SA-dependent H2O2 production in vitro in line with their low SA-dependent stress signaling responses in vivo. This provides quantitative and kinetic evidence that SA acts at or near the ubiquinone binding site of SDH to stimulate activity and contributes to plant stress signaling by increased rates of mitochondrial H2O2 production, leading to part of the SA-dependent transcriptional response in plant cells.
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Affiliation(s)
- Katharina Belt
- ARC Centre of Excellence in Plant Energy Biology, Faculty of Science, Bayliss Building M316, The University of Western Australia, 35 Stirling Highway, Crawley 6009, Western Australia, Australia (K.B., S.H., O.V.A., A.H.M.)
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Agriculture and Food, Wembley, Washington 6913, Australia (L.F.T., H.C., K.B.S.); and
- University of Western Australia Institute of Agriculture, University of Western Australia, Crawley, Washington 6009, Australia (K.B.S.)
| | - Shaobai Huang
- ARC Centre of Excellence in Plant Energy Biology, Faculty of Science, Bayliss Building M316, The University of Western Australia, 35 Stirling Highway, Crawley 6009, Western Australia, Australia (K.B., S.H., O.V.A., A.H.M.)
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Agriculture and Food, Wembley, Washington 6913, Australia (L.F.T., H.C., K.B.S.); and
- University of Western Australia Institute of Agriculture, University of Western Australia, Crawley, Washington 6009, Australia (K.B.S.)
| | - Louise F Thatcher
- ARC Centre of Excellence in Plant Energy Biology, Faculty of Science, Bayliss Building M316, The University of Western Australia, 35 Stirling Highway, Crawley 6009, Western Australia, Australia (K.B., S.H., O.V.A., A.H.M.)
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Agriculture and Food, Wembley, Washington 6913, Australia (L.F.T., H.C., K.B.S.); and
- University of Western Australia Institute of Agriculture, University of Western Australia, Crawley, Washington 6009, Australia (K.B.S.)
| | - Hayley Casarotto
- ARC Centre of Excellence in Plant Energy Biology, Faculty of Science, Bayliss Building M316, The University of Western Australia, 35 Stirling Highway, Crawley 6009, Western Australia, Australia (K.B., S.H., O.V.A., A.H.M.)
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Agriculture and Food, Wembley, Washington 6913, Australia (L.F.T., H.C., K.B.S.); and
- University of Western Australia Institute of Agriculture, University of Western Australia, Crawley, Washington 6009, Australia (K.B.S.)
| | - Karam B Singh
- ARC Centre of Excellence in Plant Energy Biology, Faculty of Science, Bayliss Building M316, The University of Western Australia, 35 Stirling Highway, Crawley 6009, Western Australia, Australia (K.B., S.H., O.V.A., A.H.M.)
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Agriculture and Food, Wembley, Washington 6913, Australia (L.F.T., H.C., K.B.S.); and
- University of Western Australia Institute of Agriculture, University of Western Australia, Crawley, Washington 6009, Australia (K.B.S.)
| | - Olivier Van Aken
- ARC Centre of Excellence in Plant Energy Biology, Faculty of Science, Bayliss Building M316, The University of Western Australia, 35 Stirling Highway, Crawley 6009, Western Australia, Australia (K.B., S.H., O.V.A., A.H.M.)
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Agriculture and Food, Wembley, Washington 6913, Australia (L.F.T., H.C., K.B.S.); and
- University of Western Australia Institute of Agriculture, University of Western Australia, Crawley, Washington 6009, Australia (K.B.S.)
| | - A Harvey Millar
- ARC Centre of Excellence in Plant Energy Biology, Faculty of Science, Bayliss Building M316, The University of Western Australia, 35 Stirling Highway, Crawley 6009, Western Australia, Australia (K.B., S.H., O.V.A., A.H.M.)
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Agriculture and Food, Wembley, Washington 6913, Australia (L.F.T., H.C., K.B.S.); and
- University of Western Australia Institute of Agriculture, University of Western Australia, Crawley, Washington 6009, Australia (K.B.S.)
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Nomura T. Function and application of a non-ester-hydrolyzing carboxylesterase discovered in tulip. Biosci Biotechnol Biochem 2017; 81:81-94. [DOI: 10.1080/09168451.2016.1240608] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Abstract
Plants have evolved secondary metabolite biosynthetic pathways of immense rich diversity. The genes encoding enzymes for secondary metabolite biosynthesis have evolved through gene duplication followed by neofunctionalization, thereby generating functional diversity. Emerging evidence demonstrates that some of those enzymes catalyze reactions entirely different from those usually catalyzed by other members of the same family; e.g. transacylation catalyzed by an enzyme similar to a hydrolytic enzyme. Tuliposide-converting enzyme (TCE), which we recently discovered from tulip, catalyzes the conversion of major defensive secondary metabolites, tuliposides, to antimicrobial tulipalins. The TCEs belong to the carboxylesterase family in the α/β-hydrolase fold superfamily, and specifically catalyze intramolecular transesterification, but not hydrolysis. This non-ester-hydrolyzing carboxylesterase is an example of an enzyme showing catalytic properties that are unpredictable from its primary structure. This review describes the biochemical and physiological aspects of tulipalin biogenesis, and the diverse functions of plant carboxylesterases in the α/β-hydrolase fold superfamily.
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Affiliation(s)
- Taiji Nomura
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, Imizu, Japan
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63
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Mindrebo JT, Nartey CM, Seto Y, Burkart MD, Noel JP. Unveiling the functional diversity of the alpha/beta hydrolase superfamily in the plant kingdom. Curr Opin Struct Biol 2016; 41:233-246. [PMID: 27662376 PMCID: PMC5687975 DOI: 10.1016/j.sbi.2016.08.005] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 08/21/2016] [Accepted: 08/22/2016] [Indexed: 12/13/2022]
Abstract
The alpha/beta hydrolase (ABH) superfamily is a widespread and functionally malleable protein fold recognized for its diverse biochemical activities across all three domains of life. ABH enzymes possess unexpected catalytic activity in the green plant lineage through selective alterations in active site architecture and chemistry. Furthermore, the ABH fold serves as the core structure for phytohormone and ligand receptors in the gibberellin, strigolactone, and karrikin signaling pathways in plants. Despite recent discoveries, the ABH family is sparsely characterized in plants, a sessile kingdom known to evolve complex and specialized chemical adaptations as survival responses to widely varying biotic and abiotic ecologies. This review calls attention to the ABH superfamily in the plant kingdom to highlight the functional adaptability of the ABH fold.
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Affiliation(s)
- Jeffrey T Mindrebo
- Department of Chemistry and Biochemistry, The University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA; Howard Hughes Medical Institute, The Salk Institute for Biological Studies, Jack H. Skirball Center for Chemical Biology and Proteomics, 10010 N. Torrey Pines Road, La Jolla, CA 92037, USA
| | - Charisse M Nartey
- Howard Hughes Medical Institute, The Salk Institute for Biological Studies, Jack H. Skirball Center for Chemical Biology and Proteomics, 10010 N. Torrey Pines Road, La Jolla, CA 92037, USA
| | - Yoshiya Seto
- Howard Hughes Medical Institute, The Salk Institute for Biological Studies, Jack H. Skirball Center for Chemical Biology and Proteomics, 10010 N. Torrey Pines Road, La Jolla, CA 92037, USA
| | - Michael D Burkart
- Department of Chemistry and Biochemistry, The University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Joseph P Noel
- Howard Hughes Medical Institute, The Salk Institute for Biological Studies, Jack H. Skirball Center for Chemical Biology and Proteomics, 10010 N. Torrey Pines Road, La Jolla, CA 92037, USA.
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64
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Rong D, Luo N, Mollet JC, Liu X, Yang Z. Salicylic Acid Regulates Pollen Tip Growth through an NPR3/NPR4-Independent Pathway. MOLECULAR PLANT 2016; 9:1478-1491. [PMID: 27575693 PMCID: PMC7513929 DOI: 10.1016/j.molp.2016.07.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 07/15/2016] [Accepted: 07/25/2016] [Indexed: 05/03/2023]
Abstract
Tip growth is a common strategy for the rapid elongation of cells to forage the environment and/or to target to long-distance destinations. In the model tip growth system of Arabidopsis pollen tubes, several small-molecule hormones regulate their elongation, but how these rapidly diffusing molecules control extremely localized growth remains mysterious. Here we show that the interconvertible salicylic acid (SA) and methylated SA (MeSA), well characterized for their roles in plant defense, oppositely regulate Arabidopsis pollen tip growth with SA being inhibitory and MeSA stimulatory. The effect of SA and MeSA was independent of known NPR3/NPR4 SA receptor-mediated signaling pathways. SA inhibited clathrin-mediated endocytosis in pollen tubes associated with an increased accumulation of less stretchable demethylated pectin in the apical wall, whereas MeSA did the opposite. Furthermore, SA and MeSA alter the apical activation of ROP1 GTPase, a key regulator of tip growth in pollen tubes, in an opposite manner. Interestingly, both MeSA methylesterase and SA methyltransferase, which catalyze the interconversion between SA and MeSA, are localized at the apical region of pollen tubes, indicating of the tip-localized production of SA and MeSA and consistent with their effects on the apical cellular activities. These findings suggest that local generation of a highly diffusible signal can regulate polarized cell growth, providing a novel mechanism of cell polarity control apart from the one involving protein and mRNA polarization.
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Affiliation(s)
- Duoyan Rong
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha 410082, China; Department of Botany and Plant Sciences, and Center for Plant Cell Biology, Institute of Integrated Genome Biology University of California, Riverside, CA 92521, USA
| | - Nan Luo
- Department of Botany and Plant Sciences, and Center for Plant Cell Biology, Institute of Integrated Genome Biology University of California, Riverside, CA 92521, USA
| | - Jean Claude Mollet
- Normandie Univ, UniRouen, Laboratoire Glycobiologie et Matrice Extracellulaire Végétale, Institute for Research and Innovation in Biomedicine, Végétal, Agronomie, Sol, et Innovation, 76821 Mont-Saint-Aignan, France
| | - Xuanming Liu
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan Province Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha 410082, China.
| | - Zhenbiao Yang
- Department of Botany and Plant Sciences, and Center for Plant Cell Biology, Institute of Integrated Genome Biology University of California, Riverside, CA 92521, USA.
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65
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Rabe F, Seitner D, Bauer L, Navarrete F, Czedik-Eysenberg A, Rabanal FA, Djamei A. Phytohormone sensing in the biotrophic fungus Ustilago maydis - the dual role of the transcription factor Rss1. Mol Microbiol 2016; 102:290-305. [PMID: 27387604 PMCID: PMC5082525 DOI: 10.1111/mmi.13460] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/05/2016] [Indexed: 12/30/2022]
Abstract
The phenolic compound salicylic acid (SA) is a key signalling molecule regulating local and systemic plant defense responses, mainly against biotrophs. Many microbial organisms, including pathogens, share the ability to degrade SA. However, the mechanism by which they perceive SA is unknown. Here we show that Ustilago maydis, the causal agent of corn smut disease, employs a so far uncharacterized SA sensing mechanism. We identified and characterized the novel SA sensing regulator, Rss1, a binuclear zinc cluster protein with dual functions as putative SA receptor and transcriptional activator regulating genes important for SA and tryptophan degradation. Rss1 represents a major component in the identified SA sensing pathway during the fungus' saprophytic stage. However, Rss1 does not have a detectable impact on virulence. The data presented in this work indicate that alternative or redundant sensing cascades exist that regulate the expression of SA-responsive genes in U. maydis during its pathogenic development.
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Affiliation(s)
- Franziska Rabe
- Vienna Biocenter (VBC), Gregor Mendel Institute (GMI), Austrian Academy of Sciences (OEAW), Dr. Bohr-Gasse 3, Vienna, 1030, Austria
| | - Denise Seitner
- Vienna Biocenter (VBC), Gregor Mendel Institute (GMI), Austrian Academy of Sciences (OEAW), Dr. Bohr-Gasse 3, Vienna, 1030, Austria
| | - Lisa Bauer
- Vienna Biocenter (VBC), Gregor Mendel Institute (GMI), Austrian Academy of Sciences (OEAW), Dr. Bohr-Gasse 3, Vienna, 1030, Austria
| | - Fernando Navarrete
- Vienna Biocenter (VBC), Gregor Mendel Institute (GMI), Austrian Academy of Sciences (OEAW), Dr. Bohr-Gasse 3, Vienna, 1030, Austria
| | - Angelika Czedik-Eysenberg
- Vienna Biocenter (VBC), Gregor Mendel Institute (GMI), Austrian Academy of Sciences (OEAW), Dr. Bohr-Gasse 3, Vienna, 1030, Austria
| | - Fernando A Rabanal
- Vienna Biocenter (VBC), Gregor Mendel Institute (GMI), Austrian Academy of Sciences (OEAW), Dr. Bohr-Gasse 3, Vienna, 1030, Austria
| | - Armin Djamei
- Vienna Biocenter (VBC), Gregor Mendel Institute (GMI), Austrian Academy of Sciences (OEAW), Dr. Bohr-Gasse 3, Vienna, 1030, Austria.
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66
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Ko M, Cho JH, Seo HH, Lee HH, Kang HY, Nguyen TS, Soh HC, Kim YS, Kim JI. Constitutive expression of a fungus-inducible carboxylesterase improves disease resistance in transgenic pepper plants. PLANTA 2016; 244:379-92. [PMID: 27074836 DOI: 10.1007/s00425-016-2514-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 03/30/2016] [Indexed: 05/10/2023]
Abstract
Resistance against anthracnose fungi was enhanced in transgenic pepper plants that accumulated high levels of a carboxylesterase, PepEST in anthracnose-susceptible fruits, with a concurrent induction of antioxidant enzymes and SA-dependent PR proteins. A pepper esterase gene (PepEST) is highly expressed during the incompatible interaction between ripe fruits of pepper (Capsicum annuum L.) and a hemibiotrophic anthracnose fungus (Colletotrichum gloeosporioides). In this study, we found that exogenous application of recombinant PepEST protein on the surface of the unripe pepper fruits led to a potentiated state for disease resistance in the fruits, including generation of hydrogen peroxide and expression of pathogenesis-related (PR) genes that encode mostly small proteins with antimicrobial activity. To elucidate the role of PepEST in plant defense, we further developed transgenic pepper plants overexpressing PepEST under the control of CaMV 35S promoter. Molecular analysis confirmed the establishment of three independent transgenic lines carrying single copy of transgenes. The level of PepEST protein was estimated to be approximately 0.002 % of total soluble protein in transgenic fruits. In response to the anthracnose fungus, the transgenic fruits displayed higher expression of PR genes, PR3, PR5, PR10, and PepThi, than non-transgenic control fruits did. Moreover, immunolocalization results showed concurrent localization of ascorbate peroxidase (APX) and PR3 proteins, along with the PepEST protein, in the infected region of transgenic fruits. Disease rate analysis revealed significantly low occurrence of anthracnose disease in the transgenic fruits, approximately 30 % of that in non-transgenic fruits. Furthermore, the transgenic plants also exhibited resistance against C. acutatum and C. coccodes. Collectively, our results suggest that overexpression of PepEST in pepper confers enhanced resistance against the anthracnose fungi by activating the defense signaling pathways.
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Affiliation(s)
- Moonkyung Ko
- Department of Biotechnology and Kumho Life Science Laboratory, Chonnam National University, Gwangju, 500-757, Republic of Korea
| | - Jung Hyun Cho
- Department of Biotechnology and Kumho Life Science Laboratory, Chonnam National University, Gwangju, 500-757, Republic of Korea
| | - Hyo-Hyoun Seo
- Department of Biotechnology and Kumho Life Science Laboratory, Chonnam National University, Gwangju, 500-757, Republic of Korea
| | - Hyun-Hwa Lee
- Department of Biology, Chosun University, Gwangju, 501-759, Republic of Korea
| | - Ha-Young Kang
- Department of Biotechnology and Kumho Life Science Laboratory, Chonnam National University, Gwangju, 500-757, Republic of Korea
| | - Thai Son Nguyen
- Department of Biotechnology and Kumho Life Science Laboratory, Chonnam National University, Gwangju, 500-757, Republic of Korea
| | - Hyun Cheol Soh
- Department of Biotechnology and Kumho Life Science Laboratory, Chonnam National University, Gwangju, 500-757, Republic of Korea
| | - Young Soon Kim
- Department of Biotechnology and Kumho Life Science Laboratory, Chonnam National University, Gwangju, 500-757, Republic of Korea.
| | - Jeong-Il Kim
- Department of Biotechnology and Kumho Life Science Laboratory, Chonnam National University, Gwangju, 500-757, Republic of Korea.
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67
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Zhao N, Lin H, Lan S, Jia Q, Chen X, Guo H, Chen F. VvMJE1 of the grapevine (Vitis vinifera) VvMES methylesterase family encodes for methyl jasmonate esterase and has a role in stress response. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2016; 102:125-32. [PMID: 26934101 DOI: 10.1016/j.plaphy.2016.02.027] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 02/12/2016] [Accepted: 02/16/2016] [Indexed: 05/10/2023]
Abstract
The known members of plant methyl esterase (MES) family catalyze the hydrolysis of a C-O ester linkage of methyl esters of several phytohormones including indole-3-acetic acid, salicylic acid and jasmonic acid. The genome of grapevine (Vitis vinifera) was found to contain 15 MES genes, designated VvMES1-15. In this report, VvMES5 was selected for molecular, biochemical and structural studies. VvMES5 is most similar to tomato methyl jasmonate esterase. E. coli-expressed recombinant VvMES5 displayed methyl jasmonate (MeJA) esterase activity, it was renamed VvMJE1. Under steady-state conditions, VvMJE1 exhibited an apparent Km value of 92.9 μM with MeJA. VvMJE1 was also shown to have lower activity with methyl salicylate (MeSA), another known substrate of the MES family, and only at high concentrations of the substrate. To understand the structural basis of VvMJE1 in discriminating MeJA and MeSA, a homolog model of VvMJE1 was made using the X-ray structure of tobacco SABP2, which encodes for methyl salicylate esterase, as a template. Interestingly, two bulky residues at the binding site and near the surface of tobacco SABP2 are replaced by relatively small residues in VvMJE1. Such a change enables the accommodation of a larger substrate MeJA in VvMJE1. The expression of VvMJE1 was compared in control grape plants and grape plants treated with one of the three stresses: heat, cold and UV-B. While the expression of VvMJE1 was not affected by heat treatment, its expression was significantly up-regulated by cold treatment and UV-B treatment. This result suggests that VvMJE1 has a role in response of grape plants to these two abiotic stresses.
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Affiliation(s)
- Nan Zhao
- Department of Plant Sciences, University of Tennessee, Knoxville, TN 37996, USA.
| | - Hong Lin
- USDA Agricultural Research Service, Crop Diseases, Pests and Genetics Research Unit, 9611 S. Riverbend Avenue, Parlier, CA 93648, USA
| | - Suque Lan
- USDA Agricultural Research Service, Crop Diseases, Pests and Genetics Research Unit, 9611 S. Riverbend Avenue, Parlier, CA 93648, USA; Institute of Cereal and Oil Crops, Hebei Academy of Agricultural and Forestry Sciences, Shijiazhuang, China
| | - Qidong Jia
- Graduate School of Genome Science and Technology, University of Tennessee, Knoxville, TN 37996, USA
| | - Xinlu Chen
- Department of Plant Sciences, University of Tennessee, Knoxville, TN 37996, USA
| | - Hong Guo
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 37996, USA
| | - Feng Chen
- Department of Plant Sciences, University of Tennessee, Knoxville, TN 37996, USA; Graduate School of Genome Science and Technology, University of Tennessee, Knoxville, TN 37996, USA.
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68
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Li H, Pu H. Crystal structure of methylesterase family member 16 (MES16) from Arabidopsis thaliana. Biochem Biophys Res Commun 2016; 474:226-231. [PMID: 27109476 DOI: 10.1016/j.bbrc.2016.04.115] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 04/20/2016] [Indexed: 11/19/2022]
Abstract
Methylesterase family member 16 (MES16) is an integral component of chlorophyll breakdown. It catalyzes the demethylation of fluorescent chlorophyll catabolite (FCC) and pheophorbide in vitro, and specifically demethylates FCC in vivo. Here we report the crystal structure of MES16 from Arabidopsis thaliana at 2.8 Å resolution. The structure confirm that MES16 is a member of the α/β-hydrolase superfamily with Ser-87, His-239, and Asp-211 as the catalytic triad. Our biochemical studies reveal that MES16 has esterase activity with methyl-indole acetic acid as the substrate, and the catalytically essential role of Ser-87 has been demonstrated.
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Affiliation(s)
- Hongmei Li
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, People's Republic of China.
| | - Hua Pu
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, People's Republic of China; University of Chinese Academy of Sciences, College of Life Science, Beijing, 101048, People's Republic of China
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69
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Manoharan RK, Shanmugam A, Hwang I, Park JI, Nou IS. Expression of salicylic acid-related genes in Brassica oleracea var. capitata during Plasmodiophora brassicae infection. Genome 2016; 59:379-91. [PMID: 27171821 DOI: 10.1139/gen-2016-0018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Brassica oleracea var. capitata (cabbage) is an important vegetable crop in Asian countries such as Korea, China, and Japan. Cabbage production is severely affected by clubroot disease caused by the soil-borne plant pathogen Plasmodiophora brassicae. During clubroot development, methyl salicylate (MeSA) is biosynthesized from salicylic acid (SA) by methyltransferase. In addition, methyl salicylate esterase (MES) plays a major role in the conversion of MeSA back into free SA. The interrelationship between MES and methytransferases during clubroot development has not been fully explored. To begin to examine these relationships, we investigated the expression of MES genes in disease-susceptible and disease-resistant plants during clubroot development. We identified three MES-encoding genes potentially involved in the defense against pathogen attack. We found that SS1 was upregulated in both the leaves and roots of B. oleracea during P. brassicae infection. These results support the conclusion that SA biosynthesis is suppressed during pathogen infection in resistant plants. We also characterized the expression of a B. oleracea BSMT gene, which appears to be involved in glycosylation rather than MeSA biosynthesis. Our results provide insight into the functions and interactions of genes for MES and methyltransferase during infection. Taken together, our findings indicate that MES genes are important candidates for use to control clubroot diseases.
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Affiliation(s)
- Ranjith Kumar Manoharan
- Department of Horticulture, Sunchon National University, 255 Jungang-ro, Suncheon, Jeonam 57922, Republic of Korea.,Department of Horticulture, Sunchon National University, 255 Jungang-ro, Suncheon, Jeonam 57922, Republic of Korea
| | - Ashokraj Shanmugam
- Department of Horticulture, Sunchon National University, 255 Jungang-ro, Suncheon, Jeonam 57922, Republic of Korea.,Department of Horticulture, Sunchon National University, 255 Jungang-ro, Suncheon, Jeonam 57922, Republic of Korea
| | - Indeok Hwang
- Department of Horticulture, Sunchon National University, 255 Jungang-ro, Suncheon, Jeonam 57922, Republic of Korea.,Department of Horticulture, Sunchon National University, 255 Jungang-ro, Suncheon, Jeonam 57922, Republic of Korea
| | - Jong-In Park
- Department of Horticulture, Sunchon National University, 255 Jungang-ro, Suncheon, Jeonam 57922, Republic of Korea.,Department of Horticulture, Sunchon National University, 255 Jungang-ro, Suncheon, Jeonam 57922, Republic of Korea
| | - Ill-Sup Nou
- Department of Horticulture, Sunchon National University, 255 Jungang-ro, Suncheon, Jeonam 57922, Republic of Korea.,Department of Horticulture, Sunchon National University, 255 Jungang-ro, Suncheon, Jeonam 57922, Republic of Korea
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70
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Šimpraga M, Takabayashi J, Holopainen JK. Language of plants: Where is the word? JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2016; 58:343-9. [PMID: 26563972 DOI: 10.1111/jipb.12447] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 11/06/2015] [Indexed: 05/03/2023]
Abstract
Plants emit biogenic volatile organic compounds (BVOCs) causing transcriptomic, metabolomic and behavioral responses in receiver organisms. Volatiles involved in such responses are often called "plant language". Arthropods having sensitive chemoreceptors can recognize language released by plants. Insect herbivores, pollinators and natural enemies respond to composition of volatiles from plants with specialized receptors responding to different types of compounds. In contrast, the mechanism of how plants "hear" volatiles has remained obscured. In a plant-plant communication, several individually emitted compounds are known to prime defense response in receiver plants with a specific manner according to the chemical structure of each volatile compound. Further, composition and ratio of volatile compounds in the plant-released plume is important in plant-insect and plant-plant interactions mediated by plant volatiles. Studies on volatile-mediated plant-plant signaling indicate that the signaling distances are rather short, usually not longer than one meter. Volatile communication from plants to insects such as pollinators could be across distances of hundreds of meters. As many of the herbivore induced VOCs have rather short atmospheric life times, we suggest that in long-distant communications with plant volatiles, reaction products in the original emitted compounds may have additional information value of the distance to emission source together with the original plant-emitted compounds.
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Affiliation(s)
- Maja Šimpraga
- Botanical Garden, Faculty of Science, Ghent University, Ledeganck 35, B-9000 Ghent, Belgium
- Department of Environmental Science, University of Eastern Finland, P.O. Box 1627 Kuopio, Finland
| | - Junji Takabayashi
- Center for Ecological Research, Kyoto University, 2-509-3 Hirano, Otsu, Shiga 520-2113, Japan
| | - Jarmo K Holopainen
- Department of Environmental Science, University of Eastern Finland, P.O. Box 1627 Kuopio, Finland
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71
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Schilmiller AL, Gilgallon K, Ghosh B, Jones AD, Last RL. Acylsugar Acylhydrolases: Carboxylesterase-Catalyzed Hydrolysis of Acylsugars in Tomato Trichomes. PLANT PHYSIOLOGY 2016; 170:1331-44. [PMID: 26811191 PMCID: PMC4775116 DOI: 10.1104/pp.15.01348] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Accepted: 01/23/2016] [Indexed: 05/05/2023]
Abstract
Glandular trichomes of cultivated tomato (Solanum lycopersicum) and many other species throughout the Solanaceae produce and secrete mixtures of sugar esters (acylsugars) on the plant aerial surfaces. In wild and cultivated tomato, these metabolites consist of a sugar backbone, typically glucose or sucrose, and two to five acyl chains esterified to various positions on the sugar core. The aliphatic acyl chains vary in length and branching and are transferred to the sugar by a series of reactions catalyzed by acylsugar acyltransferases. A phenotypic screen of a set of S. lycopersicum M82 × Solanum pennellii LA0716 introgression lines identified a dominant genetic locus on chromosome 5 from the wild relative that affected total acylsugar levels. Genetic mapping revealed that the reduction in acylsugar levels was consistent with the presence and increased expression of two S. pennellii genes (Sopen05g030120 and Sopen05g030130) encoding putative carboxylesterase enzymes of the α/β-hydrolase superfamily. These two enzymes, named ACYLSUGAR ACYLHYDROLASE1 (ASH1) and ASH2, were shown to remove acyl chains from specific positions of certain types of acylsugars in vitro. A survey of related genes in M82 and LA0716 identified another trichome-expressed ASH gene on chromosome 9 (M82, Solyc09g075710; LA0716, Sopen09g030520) encoding a protein with similar activity. Characterization of the in vitro activities of the SpASH enzymes showed reduced activities with acylsugars produced by LA0716, presumably contributing to the high-level production of acylsugars in the presence of highly expressed SpASH genes.
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Affiliation(s)
- Anthony L Schilmiller
- Department of Biochemistry and Molecular Biology (A.L.S, K.G., B.G., A.D.J., R.L.L.), Department of Chemistry (A.D.J.), and Department of Plant Biology (R.L.L.), Michigan State University, East Lansing, Michigan 48824-1319
| | - Karin Gilgallon
- Department of Biochemistry and Molecular Biology (A.L.S, K.G., B.G., A.D.J., R.L.L.), Department of Chemistry (A.D.J.), and Department of Plant Biology (R.L.L.), Michigan State University, East Lansing, Michigan 48824-1319
| | - Banibrata Ghosh
- Department of Biochemistry and Molecular Biology (A.L.S, K.G., B.G., A.D.J., R.L.L.), Department of Chemistry (A.D.J.), and Department of Plant Biology (R.L.L.), Michigan State University, East Lansing, Michigan 48824-1319
| | - A Daniel Jones
- Department of Biochemistry and Molecular Biology (A.L.S, K.G., B.G., A.D.J., R.L.L.), Department of Chemistry (A.D.J.), and Department of Plant Biology (R.L.L.), Michigan State University, East Lansing, Michigan 48824-1319
| | - Robert L Last
- Department of Biochemistry and Molecular Biology (A.L.S, K.G., B.G., A.D.J., R.L.L.), Department of Chemistry (A.D.J.), and Department of Plant Biology (R.L.L.), Michigan State University, East Lansing, Michigan 48824-1319
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Devamani T, Rauwerdink AM, Lun-zer M, Jones BJ, Mooney JL, Tan MAO, Zhang ZJ, Xu JH, Dean AM, Kazlauskas RJ. Catalytic Promiscuity of Ancestral Esterases and Hydroxynitrile Lyases. J Am Chem Soc 2016; 138:1046-56. [PMID: 26736133 PMCID: PMC5466365 DOI: 10.1021/jacs.5b12209] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Catalytic promiscuity is a useful, but accidental, enzyme property, so finding catalytically promiscuous enzymes in nature is inefficient. Some ancestral enzymes were branch points in the evolution of new enzymes and are hypothesized to have been promiscuous. To test the hypothesis that ancestral enzymes were more promiscuous than their modern descendants, we reconstructed ancestral enzymes at four branch points in the divergence hydroxynitrile lyases (HNL's) from esterases ∼ 100 million years ago. Both enzyme types are α/β-hydrolase-fold enzymes and have the same catalytic triad, but differ in reaction type and mechanism. Esterases catalyze hydrolysis via an acyl enzyme intermediate, while lyases catalyze an elimination without an intermediate. Screening ancestral enzymes and their modern descendants with six esterase substrates and six lyase substrates found higher catalytic promiscuity among the ancestral enzymes (P < 0.01). Ancestral esterases were more likely to catalyze a lyase reaction than modern esterases, and the ancestral HNL was more likely to catalyze ester hydrolysis than modern HNL's. One ancestral enzyme (HNL1) along the path from esterase to hydroxynitrile lyases was especially promiscuous and catalyzed both hydrolysis and lyase reactions with many substrates. A broader screen tested mechanistically related reactions that were not selected for by evolution: decarboxylation, Michael addition, γ-lactam hydrolysis and 1,5-diketone hydrolysis. The ancestral enzymes were more promiscuous than their modern descendants (P = 0.04). Thus, these reconstructed ancestral enzymes are catalytically promiscuous, but HNL1 is especially so.
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Affiliation(s)
- Titu Devamani
- University of Minnesota, Department of Biochemistry, Molecular Biology & Biophysics and The Biotechnology Institute, 1479 Gortner Avenue, Saint Paul, MN 55108 USA
| | - Alissa M. Rauwerdink
- University of Minnesota, Department of Biochemistry, Molecular Biology & Biophysics and The Biotechnology Institute, 1479 Gortner Avenue, Saint Paul, MN 55108 USA
| | - Mark Lun-zer
- University of Minnesota, Department of Ecology, Evolution & Behavior and The Biotechnology Institute, 1479 Gortner Avenue, Saint Paul, MN 55108 USA
| | - Bryan J. Jones
- University of Minnesota, Department of Biochemistry, Molecular Biology & Biophysics and The Biotechnology Institute, 1479 Gortner Avenue, Saint Paul, MN 55108 USA
| | - Joanna L. Mooney
- University of Minnesota, Department of Biochemistry, Molecular Biology & Biophysics and The Biotechnology Institute, 1479 Gortner Avenue, Saint Paul, MN 55108 USA
| | | | - Zhi-Jun Zhang
- East China University of Science and Technology, School of Biotechnology, Meilong Road 130, Shanghai 200237 P. R. China
| | - Jian-He Xu
- East China University of Science and Technology, School of Biotechnology, Meilong Road 130, Shanghai 200237 P. R. China
| | - Antony M. Dean
- University of Minnesota, Department of Ecology, Evolution & Behavior and The Biotechnology Institute, 1479 Gortner Avenue, Saint Paul, MN 55108 USA
- Sun Yat-sen University, Institute of Ecology and Evolution, No.135, Xinggang West Road, Guangzhou, 510275 P. R. China
| | - Romas J. Kazlauskas
- University of Minnesota, Department of Biochemistry, Molecular Biology & Biophysics and The Biotechnology Institute, 1479 Gortner Avenue, Saint Paul, MN 55108 USA
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73
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Hikage T, Yamagishi N, Takahashi Y, Saitoh Y, Yoshikawa N, Tsutsumi KI. Allelic variants of the esterase gene W14/15 differentially regulate overwinter survival in perennial gentian (Gentiana L.). Mol Genet Genomics 2015; 291:989-97. [PMID: 26701352 DOI: 10.1007/s00438-015-1160-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Accepted: 12/14/2015] [Indexed: 11/25/2022]
Abstract
Overwinter survival has to be under critical regulation in the lifecycle of herbaceous perennial plants. Gentians (Gentiana L.) maintain their perennial life style through producing dormant and freezing-tolerant overwinter buds (OWBs) to overcome cold winter. However, the mechanism acting on such an overwinter survival and the genes/proteins contributing to it have been poorly understood. Previously, we identified an OWB-enriched protein W14/15, a member of a group of α/β hydrolase fold superfamily that is implicated in regulation of hormonal action in plants. The W14/15 gene has more than ten variant types in Gentiana species. However, roles of the W14/15 gene in OWB survival and functional difference among those variants have been unclear. In the present study, we examined whether the W14/15 gene variants are involved in the mechanism acting on overwinter survival, by crossing experiments using cultivars carrying different W14/15 variant alleles and virus-induced gene silencing experiments. We found that particular types of the W14/15 variants (W15a types) contributed toward obtaining high ability of overwinter survival, while other types (W14b types) did not, or even interfered with the former type gene. This study demonstrates two findings; first, contribution of esterase genes to winter hardiness, and second, paired set or paired partner among the allelic variants determines the ability of overwinter survival.
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Affiliation(s)
- Takashi Hikage
- United Graduate School of Agricultural Sciences, Iwate University, Morioka, Iwate, 020-8550, Japan
- Hachimantai City Floricultural Research and Development Center, Hachimantai, Iwate, 028-7592, Japan
| | - Noriko Yamagishi
- United Graduate School of Agricultural Sciences, Iwate University, Morioka, Iwate, 020-8550, Japan
| | - Yui Takahashi
- Cryobiofrontier Research Center, Iwate University, Morioka, Iwate, 020-8550, Japan
| | - Yasushi Saitoh
- United Graduate School of Agricultural Sciences, Iwate University, Morioka, Iwate, 020-8550, Japan
- Cryobiofrontier Research Center, Iwate University, Morioka, Iwate, 020-8550, Japan
| | - Nobuyuki Yoshikawa
- United Graduate School of Agricultural Sciences, Iwate University, Morioka, Iwate, 020-8550, Japan
| | - Ken-Ichi Tsutsumi
- United Graduate School of Agricultural Sciences, Iwate University, Morioka, Iwate, 020-8550, Japan.
- Cryobiofrontier Research Center, Iwate University, Morioka, Iwate, 020-8550, Japan.
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74
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Rauwerdink A, Lunzer M, Devamani T, Jones B, Mooney J, Zhang ZJ, Xu JH, Kazlauskas RJ, Dean AM. Evolution of a Catalytic Mechanism. Mol Biol Evol 2015; 33:971-9. [PMID: 26681154 DOI: 10.1093/molbev/msv338] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The means by which superfamilies of specialized enzymes arise by gene duplication and functional divergence are poorly understood. The escape from adaptive conflict hypothesis, which posits multiple copies of a gene encoding a primitive inefficient and highly promiscuous generalist ancestor, receives support from experiments showing that resurrected ancestral enzymes are indeed more substrate-promiscuous than their modern descendants. Here, we provide evidence in support of an alternative model, the innovation-amplification-divergence hypothesis, which posits a single-copied ancestor as efficient and specific as any modern enzyme. We argue that the catalytic mechanisms of plant esterases and descendent acetone cyanohydrin lyases are incompatible with each other (e.g., the reactive substrate carbonyl must bind in opposite orientations in the active site). We then show that resurrected ancestral plant esterases are as catalytically specific as modern esterases, that the ancestor of modern acetone cyanohydrin lyases was itself only very weakly promiscuous, and that improvements in lyase activity came at the expense of esterase activity. These observations support the innovation-amplification-divergence hypothesis, in which an ancestor gains a weak promiscuous activity that is improved by selection at the expense of the ancestral activity, and not the escape from adaptive conflict in which an inefficient generalist ancestral enzyme steadily loses promiscuity throughout the transition to a highly active specialized modern enzyme.
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Affiliation(s)
- Alissa Rauwerdink
- Department of Biochemistry, Molecular Biology & Biophysics and the Biotechnology Institute, University of Minnesota
| | - Mark Lunzer
- Department of Biochemistry, Molecular Biology & Biophysics and the Biotechnology Institute, University of Minnesota
| | - Titu Devamani
- Department of Biochemistry, Molecular Biology & Biophysics and the Biotechnology Institute, University of Minnesota
| | - Bryan Jones
- Department of Biochemistry, Molecular Biology & Biophysics and the Biotechnology Institute, University of Minnesota
| | - Joanna Mooney
- Department of Biochemistry, Molecular Biology & Biophysics and the Biotechnology Institute, University of Minnesota
| | - Zhi-Jun Zhang
- Department of Biochemistry, Molecular Biology & Biophysics and the Biotechnology Institute, University of Minnesota Department of Biotechnology, East China University of Science and Technology, Shanghai, PR China
| | - Jian-He Xu
- Department of Biochemistry, Molecular Biology & Biophysics and the Biotechnology Institute, University of Minnesota Department of Biotechnology, East China University of Science and Technology, Shanghai, PR China
| | - Romas J Kazlauskas
- Department of Biochemistry, Molecular Biology & Biophysics and the Biotechnology Institute, University of Minnesota
| | - Antony M Dean
- Department of Biochemistry, Molecular Biology & Biophysics and the Biotechnology Institute, University of Minnesota Department of Ecology, Evolution and Behavior, University of Minnesota College of Ecology and Evolution, Sun Yat-Sen University, Guangzhou, PR China
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Wu F, Kerčmar P, Zhang C, Stöckigt J. Sarpagan-Ajmalan-Type Indoles: Biosynthesis, Structural Biology, and Chemo-Enzymatic Significance. THE ALKALOIDS. CHEMISTRY AND BIOLOGY 2015; 76:1-61. [PMID: 26827882 DOI: 10.1016/bs.alkal.2015.10.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The biosynthetic pathway of the monoterpenoid indole alkaloid ajmaline in the genus Rauvolfia, in particular Rauvolfia serpentina Benth. ex Kurz, is one of the few pathways that have been comprehensively uncovered. Every step in the progress of plant alkaloid biosynthesis research is due to the endeavors of several generations of scientists and the advancement of technologies. The tissue and cell suspension cultures developed in the 1970s by M.H. Zenk enabled the extraction of alkaloids and crude enzymes for use as experimental materials, thus establishing the foundation for further research on enzymatic reaction networks. In vivo NMR technology was first used in biosynthetic investigations in the 1990s following the invention of high-field cryo-NMR, which allowed the rapid and reliable detection of bioconversion processes within living plant cells. Shortly before, in 1988, a milestone was reached with the heterologous expression of the strictosidine synthase cDNA, which paved the way for the application of "reverse genetics" and "macromolecular crystallography." Both methods allowed the structural analysis of several Rauvolfia enzymes involved in ajmaline biosynthesis and expanded our knowledge of the enzyme mechanisms, substrate specificities, and structure-activity relationships. It also opened the door for rational enzyme engineering and metabolic steering. Today, the research focus of ajmaline biosynthesis is shifting from "delineation" to "utilization." The Pictet-Spenglerase strictosidine synthase, strictosidine glucosidase, together with raucaffricine glucosidase, as pioneers in this area, have become useful tools to generate "privileged structures" and "diversity oriented" syntheses, which may help to construct novel scaffolds and to set up libraries of sarpagan-ajmalan-type alkaloids in chemo-enzymatic approaches.
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Affiliation(s)
- Fangrui Wu
- Yunnan Provincial Key Laboratory of Entomological Biopharmaceutical R&D, Dali University, Dali, Yunnan, P.R. China; Department of Pharmacology, Baylor College of Medicine, Houston, TX, USA
| | | | - Chenggui Zhang
- Yunnan Provincial Key Laboratory of Entomological Biopharmaceutical R&D, Dali University, Dali, Yunnan, P.R. China
| | - Joachim Stöckigt
- Yunnan Provincial Key Laboratory of Entomological Biopharmaceutical R&D, Dali University, Dali, Yunnan, P.R. China; College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang, P.R. China
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76
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Dieryckx C, Gaudin V, Dupuy JW, Bonneu M, Girard V, Job D. Beyond plant defense: insights on the potential of salicylic and methylsalicylic acid to contain growth of the phytopathogen Botrytis cinerea. FRONTIERS IN PLANT SCIENCE 2015; 6:859. [PMID: 26528317 PMCID: PMC4607878 DOI: 10.3389/fpls.2015.00859] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 09/29/2015] [Indexed: 05/27/2023]
Abstract
Using Botrytis cinerea we confirmed in the present work several previous studies showing that salicylic acid, a main plant hormone, inhibits fungal growth in vitro. Such an inhibitory effect was also observed for the two salicylic acid derivatives, methylsalicylic and acetylsalicylic acid. In marked contrast, 5-sulfosalicylic acid was totally inactive. Comparative proteomics from treated vs. control mycelia showed that both the intracellular and extracellular proteomes were affected in the presence of salicylic acid or methylsalicylic acid. These data suggest several mechanisms that could potentially account for the observed fungal growth inhibition, notably pH regulation, metal homeostasis, mitochondrial respiration, ROS accumulation and cell wall remodeling. The present observations support a role played by the phytohormone SA and derivatives in directly containing the pathogen. Data are available via ProteomeXchange with identifier PXD002873.
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Affiliation(s)
- Cindy Dieryckx
- Laboratoire Mixte UMR 5240, Plateforme de Protéomique, Centre National de la Recherche ScientifiqueLyon, France
| | - Vanessa Gaudin
- Laboratoire Mixte UMR 5240, Plateforme de Protéomique, Centre National de la Recherche ScientifiqueLyon, France
| | - Jean-William Dupuy
- Plateforme Protéome, Centre de Génomique Fonctionnelle, Université de BordeauxBordeaux, France
| | - Marc Bonneu
- Plateforme Protéome, Centre de Génomique Fonctionnelle, Université de BordeauxBordeaux, France
| | - Vincent Girard
- Laboratoire Mixte UMR 5240, Plateforme de Protéomique, Centre National de la Recherche ScientifiqueLyon, France
| | - Dominique Job
- Laboratoire Mixte UMR 5240, Plateforme de Protéomique, Centre National de la Recherche ScientifiqueLyon, France
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77
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Rauwerdink A, Kazlauskas RJ. How the Same Core Catalytic Machinery Catalyzes 17 Different Reactions: the Serine-Histidine-Aspartate Catalytic Triad of α/β-Hydrolase Fold Enzymes. ACS Catal 2015; 5:6153-6176. [PMID: 28580193 DOI: 10.1021/acscatal.5b01539] [Citation(s) in RCA: 186] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Enzymes within a family often catalyze different reactions. In some cases, this variety stems from different catalytic machinery, but in other cases the machinery is identical; nevertheless, the enzymes catalyze different reactions. In this review, we examine the subset of α/β-hydrolase fold enzymes that contain the serine-histidine-aspartate catalytic triad. In spite of having the same protein fold and the same core catalytic machinery, these enzymes catalyze seventeen different reaction mechanisms. The most common reactions are hydrolysis of C-O, C-N and C-C bonds (Enzyme Classification (EC) group 3), but other enzymes are oxidoreductases (EC group 1), acyl transferases (EC group 2), lyases (EC group 4) or isomerases (EC group 5). Hydrolysis reactions often follow the canonical esterase mechanism, but eight variations occur where either the formation or cleavage of the acyl enzyme intermediate differs. The remaining eight mechanisms are lyase-type elimination reactions, which do not have an acyl enzyme intermediate and, in four cases, do not even require the catalytic serine. This diversity of mechanisms from the same catalytic triad stems from the ability of the enzymes to bind different substrates, from the requirements for different chemical steps imposed by these new substrates and, only in about half of the cases, from additional hydrogen bond partners or additional general acids/bases in the active site. This detailed analysis shows that binding differences and non-catalytic residues create new mechanisms and are essential for understanding and designing efficient enzymes.
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Affiliation(s)
- Alissa Rauwerdink
- Department of Biochemistry, Molecular Biology & Biophysics and The Biotechnology Institute, University of Minnesota, Saint Paul, Minnesota 55108, United States
| | - Romas J. Kazlauskas
- Department of Biochemistry, Molecular Biology & Biophysics and The Biotechnology Institute, University of Minnesota, Saint Paul, Minnesota 55108, United States
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78
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Dutt M, Barthe G, Irey M, Grosser J. Transgenic Citrus Expressing an Arabidopsis NPR1 Gene Exhibit Enhanced Resistance against Huanglongbing (HLB; Citrus Greening). PLoS One 2015; 10:e0137134. [PMID: 26398891 PMCID: PMC4580634 DOI: 10.1371/journal.pone.0137134] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2015] [Accepted: 08/12/2015] [Indexed: 11/18/2022] Open
Abstract
Commercial sweet orange cultivars lack resistance to Huanglongbing (HLB), a serious phloem limited bacterial disease that is usually fatal. In order to develop sustained disease resistance to HLB, transgenic sweet orange cultivars ‘Hamlin’ and ‘Valencia’ expressing an Arabidopsis thaliana NPR1 gene under the control of a constitutive CaMV 35S promoter or a phloem specific Arabidopsis SUC2 (AtSUC2) promoter were produced. Overexpression of AtNPR1 resulted in trees with normal phenotypes that exhibited enhanced resistance to HLB. Phloem specific expression of NPR1 was equally effective for enhancing disease resistance. Transgenic trees exhibited reduced diseased severity and a few lines remained disease-free even after 36 months of planting in a high-disease pressure field site. Expression of the NPR1 gene induced expression of several native genes involved in the plant defense signaling pathways. The AtNPR1 gene being plant derived can serve as a component for the development of an all plant T-DNA derived consumer friendly GM tree.
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Affiliation(s)
- Manjul Dutt
- Citrus Research and Education Center, University of Florida, Lake Alfred, Florida, United States of America
- * E-mail:
| | - Gary Barthe
- Citrus Research and Education Center, University of Florida, Lake Alfred, Florida, United States of America
| | - Michael Irey
- Southern Gardens Citrus, Clewiston, Florida, United States of America
| | - Jude Grosser
- Citrus Research and Education Center, University of Florida, Lake Alfred, Florida, United States of America
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79
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Yao J, Guo H, Chaiprasongsuk M, Zhao N, Chen F, Yang X, Guo H. Substrate-Assisted Catalysis in the Reaction Catalyzed by Salicylic Acid Binding Protein 2 (SABP2), a Potential Mechanism of Substrate Discrimination for Some Promiscuous Enzymes. Biochemistry 2015; 54:5366-75. [PMID: 26244568 DOI: 10.1021/acs.biochem.5b00638] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Although one of an enzyme's hallmarks is the high specificity for their natural substrates, substrate promiscuity has been reported more frequently. It is known that promiscuous enzymes generally show different catalytic efficiencies to different substrates, but our understanding of the origin of such differences is still lacking. Here we report the results of quantum mechanical/molecular mechanical simulations and an experimental study of salicylic acid binding protein 2 (SABP2). SABP2 has promiscuous esterase activity toward a series of substrates but shows a high activity toward its natural substrate, methyl salicylate (MeSA). Our results demonstrate that this enzyme may use substrate-assisted catalysis involving the hydroxyl group from MeSA to enhance the activity and achieve substrate discrimination.
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Affiliation(s)
- Jianzhuang Yao
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee , Knoxville, Tennessee 37996, United States
- UT/ORNL Center for Molecular Biophysics, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37830, United States
| | - Haobo Guo
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee , Knoxville, Tennessee 37996, United States
- UT/ORNL Center for Molecular Biophysics, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37830, United States
| | - Minta Chaiprasongsuk
- Department of Plant Sciences, University of Tennessee , Knoxville, Tennessee 37996, United States
| | - Nan Zhao
- Department of Plant Sciences, University of Tennessee , Knoxville, Tennessee 37996, United States
| | - Feng Chen
- Department of Plant Sciences, University of Tennessee , Knoxville, Tennessee 37996, United States
| | - Xiaohan Yang
- Biosciences Division, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
| | - Hong Guo
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee , Knoxville, Tennessee 37996, United States
- UT/ORNL Center for Molecular Biophysics, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37830, United States
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80
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Huang J, Jones BJ, Kazlauskas RJ. Stabilization of an α/β-Hydrolase by Introducing Proline Residues: Salicylic Acid Binding Protein 2 from Tobacco. Biochemistry 2015; 54:4330-41. [PMID: 26110207 PMCID: PMC4557962 DOI: 10.1021/acs.biochem.5b00333] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
α/β-Hydrolases are important enzymes for biocatalysis, but their stability often limits their application. We investigated a plant esterase, salicylic acid binding protein 2 (SABP2), as a model α/β-hydrolase. SABP2 shows typical stability to urea (unfolding free energy 6.9 ± 1.5 kcal/mol) and to heat inactivation (T1/2 15min 49.2 ± 0.5 °C). Denaturation in urea occurs in two steps, but heat inactivation occurs in a single step. The first unfolding step in urea eliminates catalytic activity. Surprisingly, we found that the first unfolding likely corresponds to the unfolding of the larger catalytic domain. Replacing selected amino acid residues with proline stabilized SABP2. Proline restricts the flexibility of the unfolded protein, thereby shifting the equilibrium toward the folded conformation. Seven locations for proline substitution were chosen either by amino acid sequence alignment with a more stable homologue or by targeting flexible regions in SABP2. Introducing proline in the catalytic domain stabilized SABP2 to the first unfolding in urea for three of five cases: L46P (+0.2 M urea), S70P (+0.1), and E215P (+0.9). Introducing proline in the cap domain did not stabilize SABP2 (two of two cases), supporting the assignment that the first unfolding corresponds to the catalytic domain. Proline substitutions in both domains stabilized SABP2 to heat inactivation: L46P (ΔT1/2 15min = +6.4 °C), S70P (+5.4), S115P (+1.8), S141P (+4.9), and E215P (+4.2). Combining substitutions did not further increase the stability to urea denaturation, but dramatically increased resistance to heat inactivation: L46P−S70P ΔT1/2 15min = +25.7 °C. This straightforward proline substitution approach may also stabilize other α/β-hydrolases.
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Affiliation(s)
- Jun Huang
- Department of Biochemistry, Molecular Biology & Biophysics and The Biotechnology Institute, University of Minnesota, 1479 Gortner Avenue, Saint Paul MN 55108 USA
- School of Biological and Chemical Engineering, Zhejiang University of Science and Technology, Hangzhou 310023, PR China
| | - Bryan J. Jones
- Department of Biochemistry, Molecular Biology & Biophysics and The Biotechnology Institute, University of Minnesota, 1479 Gortner Avenue, Saint Paul MN 55108 USA
| | - Romas J. Kazlauskas
- Department of Biochemistry, Molecular Biology & Biophysics and The Biotechnology Institute, University of Minnesota, 1479 Gortner Avenue, Saint Paul MN 55108 USA
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81
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Nomura T, Murase T, Ogita S, Kato Y. Molecular identification of tuliposide B-converting enzyme: a lactone-forming carboxylesterase from the pollen of tulip. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2015; 83:252-62. [PMID: 25997073 DOI: 10.1111/tpj.12883] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2014] [Revised: 04/23/2015] [Accepted: 05/12/2015] [Indexed: 05/10/2023]
Abstract
6-Tuliposides A (PosA) and B (PosB), which are the major secondary metabolites in tulip (Tulipa gesneriana), are enzymatically converted to the antimicrobial lactonized aglycons, tulipalins A (PaA) and B (PaB), respectively. We recently identified a PosA-converting enzyme (TCEA) as the first reported member of the lactone-forming carboxylesterases. Herein, we describe the identification of another lactone-forming carboxylesterase, PosB-converting enzyme (TCEB), which preferentially reacts with PosB to give PaB. This enzyme was isolated from tulip pollen, which showed high PosB-converting activity. Purified TCEB exhibited greater activity towards PosB than PosA, which was contrary to that of the TCEA. Novel cDNA (TgTCEB1) encoding the TCEB was isolated from tulip pollen. TgTCEB1 belonged to the carboxylesterase family and was approximately 50% identical to the TgTCEA polypeptides. Functional characterization of the recombinant enzyme verified that TgTCEB1 catalyzed the conversion of PosB to PaB with an activity comparable with the native TCEB. RT-qPCR analysis of each part of plant revealed that TgTCEB1 transcripts were limited almost exclusively to the pollen. Furthermore, the immunostaining of the anther cross-section using anti-TgTCEB1 polyclonal antibody verified that TgTCEB1 was specifically expressed in the pollen grains, but not in the anther cells. N-terminal transit peptide of TgTCEB1 was shown to function as plastid-targeted signal. Taken together, these results indicate that mature TgTCEB1 is specifically localized in plastids of pollen grains. Interestingly, PosB, the substrate of TgTCEB1, accumulated on the pollen surface, but not in the intracellular spaces of pollen grains.
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Affiliation(s)
- Taiji Nomura
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan
| | - Tatsunori Murase
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan
| | - Shinjiro Ogita
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan
| | - Yasuo Kato
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan
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82
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Ludwig-Müller J, Jülke S, Geiß K, Richter F, Mithöfer A, Šola I, Rusak G, Keenan S, Bulman S. A novel methyltransferase from the intracellular pathogen Plasmodiophora brassicae methylates salicylic acid. MOLECULAR PLANT PATHOLOGY 2015; 16:349-64. [PMID: 25135243 PMCID: PMC6638400 DOI: 10.1111/mpp.12185] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
The obligate biotrophic pathogen Plasmodiophora brassicae causes clubroot disease in Arabidopsis thaliana, which is characterized by large root galls. Salicylic acid (SA) production is a defence response in plants, and its methyl ester is involved in systemic signalling. Plasmodiophora brassicae seems to suppress plant defence reactions, but information on how this is achieved is scarce. Here, we profile the changes in SA metabolism during Arabidopsis clubroot disease. The accumulation of SA and the emission of methylated SA (methyl salicylate, MeSA) were observed in P. brassicae-infected Arabidopsis 28 days after inoculation. There is evidence that MeSA is transported from infected roots to the upper plant. Analysis of the mutant Atbsmt1, deficient in the methylation of SA, indicated that the Arabidopsis SA methyltransferase was not responsible for alterations in clubroot symptoms. We found that P. brassicae possesses a methyltransferase (PbBSMT) with homology to plant methyltransferases. The PbBSMT gene is maximally transcribed when SA production is highest. By heterologous expression and enzymatic analyses, we showed that PbBSMT can methylate SA, benzoic and anthranilic acids.
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Affiliation(s)
- Jutta Ludwig-Müller
- Institute of Botany, Technische Universität Dresden, 01062, Dresden, Germany
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Protein evolution analysis of S-hydroxynitrile lyase by complete sequence design utilizing the INTMSAlign software. Sci Rep 2015; 5:8193. [PMID: 25645341 PMCID: PMC4648443 DOI: 10.1038/srep08193] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Accepted: 01/12/2015] [Indexed: 01/05/2023] Open
Abstract
Development of software and methods for design of complete sequences of functional proteins could contribute to studies of protein engineering and protein evolution. To this end, we developed the INTMSAlign software, and used it to design functional proteins and evaluate their usefulness. The software could assign both consensus and correlation residues of target proteins. We generated three protein sequences with S-selective hydroxynitrile lyase (S-HNL) activity, which we call designed S-HNLs; these proteins folded as efficiently as the native S-HNL. Sequence and biochemical analysis of the designed S-HNLs suggested that accumulation of neutral mutations occurs during the process of S-HNLs evolution from a low-activity form to a high-activity (native) form. Taken together, our results demonstrate that our software and the associated methods could be applied not only to design of complete sequences, but also to predictions of protein evolution, especially within families such as esterases and S-HNLs.
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84
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Bektas Y, Eulgem T. Synthetic plant defense elicitors. FRONTIERS IN PLANT SCIENCE 2015; 5:804. [PMID: 25674095 PMCID: PMC4306307 DOI: 10.3389/fpls.2014.00804] [Citation(s) in RCA: 133] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 12/22/2014] [Indexed: 05/18/2023]
Abstract
To defend themselves against invading pathogens plants utilize a complex regulatory network that coordinates extensive transcriptional and metabolic reprogramming. Although many of the key players of this immunity-associated network are known, the details of its topology and dynamics are still poorly understood. As an alternative to forward and reverse genetic studies, chemical genetics-related approaches based on bioactive small molecules have gained substantial popularity in the analysis of biological pathways and networks. Use of such molecular probes can allow researchers to access biological space that was previously inaccessible to genetic analyses due to gene redundancy or lethality of mutations. Synthetic elicitors are small drug-like molecules that induce plant defense responses, but are distinct from known natural elicitors of plant immunity. While the discovery of some synthetic elicitors had already been reported in the 1970s, recent breakthroughs in combinatorial chemical synthesis now allow for inexpensive high-throughput screens for bioactive plant defense-inducing compounds. Along with powerful reverse genetics tools and resources available for model plants and crop systems, comprehensive collections of new synthetic elicitors will likely allow plant scientists to study the intricacies of plant defense signaling pathways and networks in an unparalleled fashion. As synthetic elicitors can protect crops from diseases, without the need to be directly toxic for pathogenic organisms, they may also serve as promising alternatives to conventional biocidal pesticides, which often are harmful for the environment, farmers and consumers. Here we are discussing various types of synthetic elicitors that have been used for studies on the plant immune system, their modes-of-action as well as their application in crop protection.
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Affiliation(s)
- Yasemin Bektas
- Center for Plant Cell Biology, Institute for Integrative Genome Biology – Department of Botany and Plant Sciences, University of CaliforniaRiverside, CA, USA
- Department of Biology, Faculty of Arts and Science, Gaziosmanpasa UniversityTokat, Turkey
| | - Thomas Eulgem
- Center for Plant Cell Biology, Institute for Integrative Genome Biology – Department of Botany and Plant Sciences, University of CaliforniaRiverside, CA, USA
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85
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Salicylic Acid Signaling in Plant Innate Immunity. PLANT HORMONE SIGNALING SYSTEMS IN PLANT INNATE IMMUNITY 2015. [DOI: 10.1007/978-94-017-9285-1_2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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86
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Bobik K, Burch-Smith TM. Chloroplast signaling within, between and beyond cells. FRONTIERS IN PLANT SCIENCE 2015; 6:781. [PMID: 26500659 PMCID: PMC4593955 DOI: 10.3389/fpls.2015.00781] [Citation(s) in RCA: 129] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 09/10/2015] [Indexed: 05/18/2023]
Abstract
The most conspicuous function of plastids is the oxygenic photosynthesis of chloroplasts, yet plastids are super-factories that produce a plethora of compounds that are indispensable for proper plant physiology and development. Given their origins as free-living prokaryotes, it is not surprising that plastids possess their own genomes whose expression is essential to plastid function. This semi-autonomous character of plastids requires the existence of sophisticated regulatory mechanisms that provide reliable communication between them and other cellular compartments. Such intracellular signaling is necessary for coordinating whole-cell responses to constantly varying environmental cues and cellular metabolic needs. This is achieved by plastids acting as receivers and transmitters of specific signals that coordinate expression of the nuclear and plastid genomes according to particular needs. In this review we will consider the so-called retrograde signaling occurring between plastids and nuclei, and between plastids and other organelles. Another important role of the plastid we will discuss is the involvement of plastid signaling in biotic and abiotic stress that, in addition to influencing retrograde signaling, has direct effects on several cellular compartments including the cell wall. We will also review recent evidence pointing to an intriguing function of chloroplasts in regulating intercellular symplasmic transport. Finally, we consider an intriguing yet less widely known aspect of plant biology, chloroplast signaling from the perspective of the entire plant. Thus, accumulating evidence highlights that chloroplasts, with their complex signaling pathways, provide a mechanism for exquisite regulation of plant development, metabolism and responses to the environment. As chloroplast processes are targeted for engineering for improved productivity the effect of such modifications on chloroplast signaling will have to be carefully considered in order to avoid unintended consequences on plant growth and development.
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Affiliation(s)
| | - Tessa M. Burch-Smith
- *Correspondence: Tessa M. Burch-Smith, Department of Biochemistry, Cellular and Molecular Biology, University of Tennessee, 1414 Cumberland Avenue, M407 Walters Life Science, Knoxville, TN 37932, USA,
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87
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Nedrud DM, Lin H, Lopez G, Padhi SK, Legatt GA, Kaz-Lauskas RJ. Uncovering divergent evolution of α/β-hydrolases: a surprising residue substitution needed to convert Hevea brasiliensis hydroxynitrile lyase into an esterase. Chem Sci 2014; 5:4265-4277. [PMID: 25346843 PMCID: PMC4206950 DOI: 10.1039/c4sc01544d] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Hevea brasiliensis hydroxynitrile lyase (HbHNL) and salicylic acid binding protein 2 (SABP2, an esterase) share 45% amino acid sequence identity, the same protein fold, and even the same catalytic triad of Ser-His-Asp. However, they catalyze different reactions: cleavage of hydroxynitriles and hydrolysis of esters, respectively. To understand how other active site differences in the two enzymes enable the same catalytic triad to catalyze different reactions, we substituted amino acid residues in HbHNL with the corresponding residues from SABP2, expecting hydroxynitrile lyase activity to decrease and esterase activity to increase. Previous mechanistic studies and x-ray crystallography suggested that esterase activity requires removal of an active site lysine and threonine from the hydroxynitrile lyase. The Thr11Gly Lys236Gly substitutions in HbHNL reduced hydroxynitrile lyase activity for cleavage of mandelonitrile 100-fold, but increased esterase activity only threefold to kcat ~ 0.1 min-1 for hydrolysis of p-nitrophenyl acetate. Adding a third substitution - Glu79His - increased esterase activity more than tenfold to kcat ~ 1.6 min-1. The specificity constant (kcat/KM) for this triple substitution variant versus wild type HbHNL shifted more than one million-fold from hydroxynitrile lyase activity (acetone cyanohydrin substrate) to esterase activity (p-nitrophenyl acetate substrate). The contribution of Glu79His to esterase activity was surprising since esterases and lipases contain many different amino acids at this position, including glutamate. Saturation mutagenesis at position 79 showed that 13 of 19 possible amino acid substitutions increased esterase activity, suggesting that removal of glutamate, not addition of histidine, increased esterase activity. Molecular modeling indicates that Glu79 disrupts esterase activity in HbHNL when its negatively charged side chain distorts the orientation of the catalytic histidine. Naturally occurring glutamate at the corresponding location of Candida lipases is uncharged due to other active site differences and does not cause the same distortion. This example of the fine tuning of the same catalytic triad for different types of catalysis by subtle interactions with other active site residues shows how difficult it is to design new catalytic reactions of enzymes.
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Affiliation(s)
- David M Nedrud
- University of Minnesota, Department of Biochemistry, Molecular Biology & Biophysics and The Biotechnology Institute, 1479 Gortner Avenue, Saint Paul, MN 55108 USA
| | - Hui Lin
- University of Minnesota, Department of Biochemistry, Molecular Biology & Biophysics and The Biotechnology Institute, 1479 Gortner Avenue, Saint Paul, MN 55108 USA
| | - Gilsinia Lopez
- University of Minnesota, Department of Biochemistry, Molecular Biology & Biophysics and The Biotechnology Institute, 1479 Gortner Avenue, Saint Paul, MN 55108 USA
| | - Santosh K Padhi
- University of Minnesota, Department of Biochemistry, Molecular Biology & Biophysics and The Biotechnology Institute, 1479 Gortner Avenue, Saint Paul, MN 55108 USA
| | - Graig A Legatt
- University of Minnesota, Department of Biochemistry, Molecular Biology & Biophysics and The Biotechnology Institute, 1479 Gortner Avenue, Saint Paul, MN 55108 USA
| | - Romas J Kaz-Lauskas
- University of Minnesota, Department of Biochemistry, Molecular Biology & Biophysics and The Biotechnology Institute, 1479 Gortner Avenue, Saint Paul, MN 55108 USA
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88
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Kumar D. Salicylic acid signaling in disease resistance. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2014; 228:127-34. [PMID: 25438793 DOI: 10.1016/j.plantsci.2014.04.014] [Citation(s) in RCA: 133] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 04/09/2014] [Accepted: 04/17/2014] [Indexed: 05/04/2023]
Abstract
Salicylic acid (SA) is a key plant hormone that mediates host responses against microbial pathogens. Identification and characterization of SA-interacting/binding proteins is a topic which has always excited scientists studying microbial defense response in plants. It is likely that discovery of a true receptor for SA may greatly advance understanding of this important signaling pathway. SABP2 with its high affinity for SA was previously considered to be a SA receptor. Despite a great deal work we may still not have true a receptor for SA. It is also entirely possible that there may be more than one receptor for SA. This scenario is more likely given the diverse role of SA in various physiological processes in plants including, modulation of opening and closing of stomatal aperture, flowering, seedling germination, thermotolerance, photosynthesis, and drought tolerance. Recent identification of NPR3, NPR4 and NPR1 as potential SA receptors and α-ketoglutarate dehydrogenase (KGDHE2), several glutathione S transferases (GSTF) such as SA binding proteins have generated more interest in this field. Some of these SA binding proteins may have direct/indirect role in plant processes other than pathogen defense signaling. Development and use of new techniques with higher specificity to identify SA-interacting proteins have shown great promise and have resulted in the identification of several new SA interactors. This review focuses on SA interaction/binding proteins identified so far and their likely role in mediating plant defenses.
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Affiliation(s)
- Dhirendra Kumar
- Department of Biological Sciences, East Tennessee State University, Box 70703, Johnson City, TN 37614, USA.
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89
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Attílio LB, Martins PK, Gómez-Krapp LM, Machado MA, Freitas-Astúa J. Genetic transformation of sweet oranges to over-express SABP2 gene. BMC Proc 2014. [PMCID: PMC4210677 DOI: 10.1186/1753-6561-8-s4-p109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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90
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Yan S, Dong X. Perception of the plant immune signal salicylic acid. CURRENT OPINION IN PLANT BIOLOGY 2014; 20:64-8. [PMID: 24840293 PMCID: PMC4143455 DOI: 10.1016/j.pbi.2014.04.006] [Citation(s) in RCA: 134] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 03/20/2014] [Accepted: 04/24/2014] [Indexed: 05/18/2023]
Abstract
Salicylic acid (SA) plays a central role in plant innate immunity. The diverse functions of this simple phenolic compound suggest that plants may have multiple SA receptors. Several SA-binding proteins have been identified using biochemical approaches. However, genetic evidence supporting that they are the bona fide SA receptors has not been forthcoming. Mutant screens revealed that NPR1 is a master regulator of SA-mediated responses. Although NPR1 cannot bind SA in a conventional ligand-binding assay, its homologs NPR3 and NPR4 bind SA and function as SA receptors. During pathogen challenge, the SA gradient generated at the infection site is sensed by NPR3 and NPR4, which serve as the adaptors for the Cullin 3-based E3 ubiquitin ligase to regulate NPR1 degradation. Consequently, NPR1 is degraded at the infection site to remove its inhibition on effector-triggered cell death and defense, whereas NPR1 accumulates in neighboring cells to promote cell survival and SA-mediated resistance.
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Affiliation(s)
- Shunping Yan
- Howard Hughes Medical Institute - Gordon and Betty Moore Foundation, Department of Biology, P.O. Box 90338, Duke University, Durham, NC 27708, USA
| | - Xinnian Dong
- Howard Hughes Medical Institute - Gordon and Betty Moore Foundation, Department of Biology, P.O. Box 90338, Duke University, Durham, NC 27708, USA.
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91
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Shah J, Chaturvedi R, Chowdhury Z, Venables B, Petros RA. Signaling by small metabolites in systemic acquired resistance. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2014; 79:645-58. [PMID: 24506415 DOI: 10.1111/tpj.12464] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Revised: 12/21/2013] [Accepted: 01/27/2014] [Indexed: 05/18/2023]
Abstract
Plants can retain the memory of a prior encounter with a pest. This memory confers upon a plant the ability to subsequently activate defenses more robustly when challenged by a pest. In plants that have retained the memory of a prior, localized, foliar infection by a pathogen, the pathogen-free distal organs develop immunity against subsequent infections by a broad-spectrum of pathogens. The long-term immunity conferred by this mechanism, which is termed systemic acquired resistance (SAR), is inheritable over a few generations. Signaling mediated by the phenolic metabolite salicylic acid (SA) is critical for the manifestation of SAR. Recent studies have described the involvement of additional small metabolites in SAR signaling, including methyl salicylate, the abietane diterpenoid dehydroabietinal, the lysine catabolite pipecolic acid, a glycerol-3-phosphate-dependent factor and the dicarboxylic acid azelaic acid. Many of these metabolites can be systemically transported through the plant and probably facilitate communication by the primary infected tissue with the distal tissues, which is essential for the activation of SAR. Some of these metabolites have been implicated in the SAR-associated rapid activation of defenses in response to subsequent exposure to the pathogen, a mechanism termed priming. Here, we summarize the role of these signaling metabolites in SAR, and the relationship between them and SA signaling in SAR.
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Affiliation(s)
- Jyoti Shah
- Department of Biological Sciences, University of North Texas, Denton, TX, 76203, USA
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92
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Zhu F, Xi DH, Yuan S, Xu F, Zhang DW, Lin HH. Salicylic acid and jasmonic acid are essential for systemic resistance against tobacco mosaic virus in Nicotiana benthamiana. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2014; 27:567-77. [PMID: 24450774 DOI: 10.1094/mpmi-11-13-0349-r] [Citation(s) in RCA: 116] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Systemic resistance is induced by pathogens and confers protection against a broad range of pathogens. Recent studies have indicated that salicylic acid (SA) derivative methyl salicylate (MeSA) serves as a long-distance phloem-mobile systemic resistance signal in tobacco, Arabidopsis, and potato. However, other experiments indicate that jasmonic acid (JA) is a critical mobile signal. Here, we present evidence suggesting both MeSA and methyl jasmonate (MeJA) are essential for systemic resistance against Tobacco mosaic virus (TMV), possibly acting as the initiating signals for systemic resistance. Foliar application of JA followed by SA triggered the strongest systemic resistance against TMV. Furthermore, we use a virus-induced gene-silencing-based genetics approach to investigate the function of JA and SA biosynthesis or signaling genes in systemic response against TMV infection. Silencing of SA or JA biosynthetic and signaling genes in Nicotiana benthamiana plants increased susceptibility to TMV. Genetic experiments also proved the irreplaceable roles of MeSA and MeJA in systemic resistance response. Systemic resistance was compromised when SA methyl transferase or JA carboxyl methyltransferase, which are required for MeSA and MeJA formation, respectively, were silenced. Moreover, high-performance liquid chromatography-mass spectrometry analysis indicated that JA and MeJA accumulated in phloem exudates of leaves at early stages and SA and MeSA accumulated at later stages, after TMV infection. Our data also indicated that JA and MeJA could regulate MeSA and SA production. Taken together, our results demonstrate that (Me)JA and (Me)SA are required for systemic resistance response against TMV.
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93
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Sharma P, Chatterjee M, Burman N, Khurana JP. Cryptochrome 1 regulates growth and development in Brassica through alteration in the expression of genes involved in light, phytohormone and stress signalling. PLANT, CELL & ENVIRONMENT 2014; 37:961-77. [PMID: 24117455 DOI: 10.1111/pce.12212] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Accepted: 10/01/2013] [Indexed: 05/19/2023]
Abstract
The blue light photoreceptors cryptochromes are ubiquitous in higher plants and are vital for regulating plant growth and development. In spite of being involved in controlling agronomically important traits like plant height and flowering time, cryptochromes have not been extensively characterized from agriculturally important crops. Here we show that overexpression of CRY1 from Brassica napus (BnCRY1), an oilseed crop, results in short-statured Brassica transgenics, likely to be less prone to wind and water lodging. The overexpression of BnCRY1 accentuates the inhibition of cell elongation in hypocotyls of transgenic seedlings. The analysis of hypocotyl growth inhibition and anthocyanin accumulation responses in BnCRY1 overexpressors substantiates that regulation of seedling photomorphogenesis by cry1 is dependent on light intensity. This study highlights that the photoactivated cry1 acts through coordinated induction and suppression of specific downstream genes involved in phytohormone synthesis or signalling, and those involved in cell wall modification, during de-etiolation of Brassica seedlings. The microarray-based transcriptome profiling also suggests that the overexpression of BnCRY1 alters abiotic/biotic stress signalling pathways; the transgenic seedlings were apparently oversensitive to abscisic acid (ABA) and mannitol.
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Affiliation(s)
- Pooja Sharma
- Interdisciplinary Centre for Plant Genomics and Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi, 110021, India
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94
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Tokunaga Y, Azetsu Y, Fukunaga K, Hatanaka T, Ito Y, Taki M. Pharmacophore generation from a drug-like core molecule surrounded by a library peptide via the 10BASEd-T on bacteriophage T7. Molecules 2014; 19:2481-96. [PMID: 24566316 PMCID: PMC6271298 DOI: 10.3390/molecules19022481] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Revised: 02/10/2014] [Accepted: 02/12/2014] [Indexed: 11/16/2022] Open
Abstract
We have achieved site-specific conjugation of several haloacetamide derivatives into designated cysteines on bacteriophage T7-displayed peptides, which are fused to T7 capsid protein gp10. This easiest gp10 based-thioetherification (10BASEd-T) undergoes almost quantitatively like a click reaction without side reaction or loss of phage infectivity. The post-translational modification yield, as well as the site-specificity, is quantitatively analyzed by a fluorescent densitometric analysis after gel electrophoresis. The detailed structure of the modified peptide on phage is identified with tandem mass spectrometry. Construction of such a peptide-fused phage library possessing non-natural core structures will be useful for future drug discovery. For this aim, we propose a novel concept of pharmacophore generation from a drug-like molecule (i.e., salicylic acid) conjugated with surrounding randomized peptides. By using the hybrid library, streptavidin-specific binders are isolated through four rounds of biopanning.
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Affiliation(s)
- Yuuki Tokunaga
- Department of Engineering Science, Bioscience and Technology Program, The Graduate School of Informatics and Engineering, The University of Electro-Communications (UEC), 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585, Japan.
| | - Yuuki Azetsu
- Department of Engineering Science, Bioscience and Technology Program, The Graduate School of Informatics and Engineering, The University of Electro-Communications (UEC), 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585, Japan.
| | - Keisuke Fukunaga
- Department of Engineering Science, Bioscience and Technology Program, The Graduate School of Informatics and Engineering, The University of Electro-Communications (UEC), 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585, Japan.
| | - Takaaki Hatanaka
- Department of Chemistry and Bioscience, Graduate School of Science and Engineering, Kagoshima University, 1-21-35 Korimoto, Kagoshima, Kagoshima 890-0065, Japan.
| | - Yuji Ito
- Department of Chemistry and Bioscience, Graduate School of Science and Engineering, Kagoshima University, 1-21-35 Korimoto, Kagoshima, Kagoshima 890-0065, Japan.
| | - Masumi Taki
- Department of Engineering Science, Bioscience and Technology Program, The Graduate School of Informatics and Engineering, The University of Electro-Communications (UEC), 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585, Japan.
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95
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Findling S, Fekete A, Warzecha H, Krischke M, Brandt H, Blume E, Mueller MJ, Berger S. Manipulation of methyl jasmonate esterase activity renders tomato more susceptible to Sclerotinia sclerotiorum. FUNCTIONAL PLANT BIOLOGY : FPB 2014; 41:133-143. [PMID: 32480973 DOI: 10.1071/fp13103] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Accepted: 07/24/2013] [Indexed: 06/11/2023]
Abstract
Jasmonic acid methyl ester has been discussed as a stress signal in plants. To investigate the relevance of reversible methylation of jasmonic acid, stress responses of transgenic tomato lines with altered expression and activity of methyl jasmonate esterase were analysed. No consistent changes in levels of methyl jasmonate, 12-oxo-phytodienoic acid, jasmonic acid, jasmonic acid isoleucine and expression of the jasmonate-responsive genes AOC and PINII between control line and RNAi as well as overexpressing lines were detectable under basal and wound-induced conditions. In contrast, reduction as well as enhancement of methyl jasmonate esterase activity resulted in increased susceptibility to the fungal pathogen Sclerotinia sclerotiorum despite higher levels of the hormonal active jasmonic acid isoleucine conjugate. Results suggest that methyl jasmonate esterase has a function in vivo in plant defence, which appears not to be related to its in vitro capacity to hydrolyse methyl jasmonate.
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Affiliation(s)
- Simone Findling
- Julius-von-Sachs-Institute for Biosciences, Pharm. Biology, Biocenter, University of Wuerzburg, Julius-von-Sachs-Platz 2, 97082 Wuerzburg, Germany
| | - Agnes Fekete
- Julius-von-Sachs-Institute for Biosciences, Pharm. Biology, Biocenter, University of Wuerzburg, Julius-von-Sachs-Platz 2, 97082 Wuerzburg, Germany
| | - Heribert Warzecha
- Present address: Technical University Darmstadt, Schnittspahnstr. 10, 64287 Darmstadt, Germany
| | - Markus Krischke
- Julius-von-Sachs-Institute for Biosciences, Pharm. Biology, Biocenter, University of Wuerzburg, Julius-von-Sachs-Platz 2, 97082 Wuerzburg, Germany
| | - Hendrik Brandt
- Julius-von-Sachs-Institute for Biosciences, Pharm. Biology, Biocenter, University of Wuerzburg, Julius-von-Sachs-Platz 2, 97082 Wuerzburg, Germany
| | - Ernst Blume
- Julius-von-Sachs-Institute for Biosciences, Pharm. Biology, Biocenter, University of Wuerzburg, Julius-von-Sachs-Platz 2, 97082 Wuerzburg, Germany
| | - Martin J Mueller
- Julius-von-Sachs-Institute for Biosciences, Pharm. Biology, Biocenter, University of Wuerzburg, Julius-von-Sachs-Platz 2, 97082 Wuerzburg, Germany
| | - Susanne Berger
- Julius-von-Sachs-Institute for Biosciences, Pharm. Biology, Biocenter, University of Wuerzburg, Julius-von-Sachs-Platz 2, 97082 Wuerzburg, Germany
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96
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Miura K, Tada Y. Regulation of water, salinity, and cold stress responses by salicylic acid. FRONTIERS IN PLANT SCIENCE 2014; 5:4. [PMID: 24478784 PMCID: PMC3899523 DOI: 10.3389/fpls.2014.00004] [Citation(s) in RCA: 281] [Impact Index Per Article: 28.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Accepted: 01/04/2014] [Indexed: 05/18/2023]
Abstract
Salicylic acid (SA) is a naturally occurring phenolic compound. SA plays an important role in the regulation of plant growth, development, ripening, and defense responses. The role of SA in the plant-pathogen relationship has been extensively investigated. In addition to defense responses, SA plays an important role in the response to abiotic stresses, including drought, low temperature, and salinity stresses. It has been suggested that SA has great agronomic potential to improve the stress tolerance of agriculturally important crops. However, the utility of SA is dependent on the concentration of the applied SA, the mode of application, and the state of the plants (e.g., developmental stage and acclimation). Generally, low concentrations of applied SA alleviate the sensitivity to abiotic stresses, and high concentrations of applied induce high levels of oxidative stress, leading to a decreased tolerance to abiotic stresses. In this article, the effects of SA on the water stress responses and regulation of stomatal closure are reviewed.
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Affiliation(s)
- Kenji Miura
- Faculty of Life and Environmental Sciences, University of TsukubaTsukuba, Japan
- *Correspondence: Kenji* Miura, Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8572, Japan e-mail:
| | - Yasuomi Tada
- Faculty of Agriculture, Kagawa UniversityKagawa, Japan
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97
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Seyfferth C, Tsuda K. Salicylic acid signal transduction: the initiation of biosynthesis, perception and transcriptional reprogramming. FRONTIERS IN PLANT SCIENCE 2014; 5:697. [PMID: 25538725 PMCID: PMC4260477 DOI: 10.3389/fpls.2014.00697] [Citation(s) in RCA: 144] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Accepted: 11/24/2014] [Indexed: 05/18/2023]
Abstract
The phytohormone salicylic acid (SA) is a small phenolic compound that regulates diverse physiological processes, in particular plant resistance against pathogens. Understanding SA-mediated signaling has been a major focus of plant research. Pathogen-induced SA is mainly synthesized via the isochorismate pathway in chloroplasts, with ICS1 (ISOCHORISMATE SYNTHASE 1) being a critical enzyme. Calcium signaling regulates activities of a subset of transcription factors thereby activating nuclear ICS1 expression. The produced SA triggers extensive transcriptional reprogramming in which NPR1 (NON-EXPRESSOR of PATHOGENESIS-RELATED GENES 1) functions as the central coactivator of TGA transcription factors. Recently, two alternative but not exclusive models for SA perception mechanisms were proposed. The first model is that NPR1 homologs, NPR3 and NPR4, perceive SA thereby regulating NPR1 protein accumulation. The second model describes that NPR1 itself perceives SA, triggering an NPR1 conformational change thereby activating SA-mediated transcription. Besides the direct SA binding, NPR1 is also regulated by SA-mediated redox changes and phosphorylation. Emerging evidence show that pathogen virulence effectors target SA signaling, further strengthening the importance of SA-mediated immunity.
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Affiliation(s)
| | - Kenichi Tsuda
- *Correspondence: Kenichi Tsuda, Department of Plant Microbe Interactions, Max Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, D-50829 Cologne, Germany e-mail:
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Király L, Künstler A, Bacsó R, Hafez Y, Király Z. Similarities and differences in plant and animal immune systems — what is inhibiting pathogens? ACTA ACUST UNITED AC 2013. [DOI: 10.1556/aphyt.48.2013.2.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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99
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Chen Y, Shen H, Wang M, Li Q, He Z. Salicyloyl-aspartate synthesized by the acetyl-amido synthetase GH3.5 is a potential activator of plant immunity in Arabidopsis. Acta Biochim Biophys Sin (Shanghai) 2013; 45:827-36. [PMID: 23842113 DOI: 10.1093/abbs/gmt078] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Salicylic acid (SA) plays a critical role in plant immunity responses against pathogen infection, especially in the establishment of systemic acquired resistance. Whether other forms of salicylates also function in plant immunity has not been explored. Our previous study has revealed that salicyloyl-aspartate (SA-Asp), the only reported endogenous SA-amino acid conjugate in plants, was highly accumulated in the Arabidopsis activation-tagged mutant gh3.5-1D after pathogen infection. In this study, we dissected SA-Asp production in Arabidopsis. In vitro biochemical experiments showed that the GH3.5 protein could catalyze the conjugation of SA with aspartic acid to form SA-Asp. SA-Asp is not converted into free SA and likely acts as a mobile molecule in plants. SA-Asp could induce pathogenesis-related (PR) gene expression and increase disease resistance to pathogenic Pseudomonas syringae. Our current study also supports the notion that GH3.5 is a multifunction enzyme in plant hormone metabolism.
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Affiliation(s)
- Ying Chen
- National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
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Kachroo A, Robin GP. Systemic signaling during plant defense. CURRENT OPINION IN PLANT BIOLOGY 2013; 16:527-33. [PMID: 23870750 DOI: 10.1016/j.pbi.2013.06.019] [Citation(s) in RCA: 141] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Revised: 06/24/2013] [Accepted: 06/25/2013] [Indexed: 05/18/2023]
Abstract
Systemic acquired resistance (SAR) is a type of pathogen-induced broad-spectrum resistance in plants. During SAR, primary infection-induced rapid generation and transportation of mobile signal(s) 'prepare' the rest of the plant for subsequent infections. Several, seemingly unrelated, mobile chemical inducers of SAR have been identified, at least two of which function in a feed-back regulatory loop with a lipid transfer-like protein. Signal(s) perception in the systemic tissues relies on the presence of an intact cuticle, the waxy layer covering all aerial parts of the plant. SAR results in chromatin modifications, which prime systemic tissues for enhanced and rapid signaling derived from salicylic acid, which along with its signaling components is key for SAR induction. This review summarizes recent findings related to SAR signal generation, movement, and perception.
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Affiliation(s)
- Aardra Kachroo
- Department of Plant Pathology, University of Kentucky, Lexington, KY 40546, United States.
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