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Wei X, Moreno-Hagelsieb G, Glick BR, Doxey AC. Comparative analysis of adenylate isopentenyl transferase genes in plant growth-promoting bacteria and plant pathogenic bacteria. Heliyon 2023; 9:e13955. [PMID: 36938451 PMCID: PMC10018469 DOI: 10.1016/j.heliyon.2023.e13955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 02/01/2023] [Accepted: 02/06/2023] [Indexed: 03/09/2023] Open
Abstract
Cytokinin is a major phytohormone that has been used in agriculture as a plant-growth stimulating compound since its initial discovery in the 1960s. Isopentenyl transferase (IPT) is a rate-limiting enzyme for cytokinin biosynthesis, which is produced by plants as well as bacteria including both plant pathogenic species and plant growth-promoting bacteria (PGPB). It has been hypothesized that there may be differences in IPT function between plant pathogens and PGPB. However, a comprehensive comparison of IPT genes between plant pathogenic and PGPB species has not been performed. Here, we performed a global comparison of IPT genes across bacteria, analyzing their DNA sequences, codon usage, phyletic distribution, promoter structure and genomic context. We found that adenylate type IPT genes are highly specific to plant-associated bacteria and subdivide into two major clades: clade A, largely composed of proteobacterial plant pathogens; and clade B, largely composed of actinomycete PGPB species. Besides these phylogenetic differences, we identified several genomic features that suggest differences in IPT regulation between pathogens and PGPB. Pathogen-associated IPTs tended to occur in predicted virulence loci, whereas PGPB-associated IPTs tended to co-occur with other genes involved in cytokinin metabolism and degradation. Pathogen-associated IPTs also showed elevated gene copy numbers, significant deviation in codon usage patterns, and extended promoters, suggesting differences in regulation and activity levels. Our results are consistent with the hypothesis that differences in IPT regulation and activity exist between plant pathogens and PGPB, which determine their effect on plant host phenotypes through the control of cytokinin levels.
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Affiliation(s)
- Xin Wei
- Department of Biology, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | | | - Bernard R. Glick
- Department of Biology, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - Andrew C. Doxey
- Department of Biology, University of Waterloo, Waterloo, ON N2L 3G1, Canada
- Corresponding author.
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2
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Antoniadi I, Mateo-Bonmatí E, Pernisová M, Brunoni F, Antoniadi M, Villalonga MGA, Ament A, Karády M, Turnbull C, Doležal K, Pěnčík A, Ljung K, Novák O. IPT9, a cis-zeatin cytokinin biosynthesis gene, promotes root growth. FRONTIERS IN PLANT SCIENCE 2022; 13:932008. [PMID: 36311087 PMCID: PMC9616112 DOI: 10.3389/fpls.2022.932008] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 08/16/2022] [Indexed: 06/12/2023]
Abstract
Cytokinin and auxin are plant hormones that coordinate many aspects of plant development. Their interactions in plant underground growth are well established, occurring at the levels of metabolism, signaling, and transport. Unlike many plant hormone classes, cytokinins are represented by more than one active molecule. Multiple mutant lines, blocking specific parts of cytokinin biosynthetic pathways, have enabled research in plants with deficiencies in specific cytokinin-types. While most of these mutants have confirmed the impeding effect of cytokinin on root growth, the ipt29 double mutant instead surprisingly exhibits reduced primary root length compared to the wild type. This mutant is impaired in cis-zeatin (cZ) production, a cytokinin-type that had been considered inactive in the past. Here we have further investigated the intriguing ipt29 root phenotype, opposite to known cytokinin functions, and the (bio)activity of cZ. Our data suggest that despite the ipt29 short-root phenotype, cZ application has a negative impact on primary root growth and can activate a cytokinin response in the stele. Grafting experiments revealed that the root phenotype of ipt29 depends mainly on local signaling which does not relate directly to cytokinin levels. Notably, ipt29 displayed increased auxin levels in the root tissue. Moreover, analyses of the differential contributions of ipt2 and ipt9 to the ipt29 short-root phenotype demonstrated that, despite its deficiency on cZ levels, ipt2 does not show any root phenotype or auxin homeostasis variation, while ipt9 mutants were indistinguishable from ipt29. We conclude that IPT9 functions may go beyond cZ biosynthesis, directly or indirectly, implicating effects on auxin homeostasis and therefore influencing plant growth.
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Affiliation(s)
- Ioanna Antoniadi
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Eduardo Mateo-Bonmatí
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Markéta Pernisová
- Plant Sciences Core Facility, Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology (CEITEC), and NCBR, Faculty of Science, Masaryk University, Brno, Czechia
| | - Federica Brunoni
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, Sweden
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences, Olomouc, Czechia
- Laboratory of Growth Regulators, Faculty of Science, Palacký University, Olomouc, Czechia
| | - Mariana Antoniadi
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, Sweden
| | | | - Anita Ament
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences, Olomouc, Czechia
- Laboratory of Growth Regulators, Faculty of Science, Palacký University, Olomouc, Czechia
| | - Michal Karády
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences, Olomouc, Czechia
- Laboratory of Growth Regulators, Faculty of Science, Palacký University, Olomouc, Czechia
| | - Colin Turnbull
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Karel Doležal
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences, Olomouc, Czechia
- Laboratory of Growth Regulators, Faculty of Science, Palacký University, Olomouc, Czechia
- Department of Chemical Biology, Faculty of Science, Palacký University, Olomouc, Czechia
| | - Aleš Pěnčík
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences, Olomouc, Czechia
- Laboratory of Growth Regulators, Faculty of Science, Palacký University, Olomouc, Czechia
| | - Karin Ljung
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Ondřej Novák
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, Sweden
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences, Olomouc, Czechia
- Laboratory of Growth Regulators, Faculty of Science, Palacký University, Olomouc, Czechia
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3
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Anand G, Gupta R, Marash I, Leibman-Markus M, Bar M. Cytokinin production and sensing in fungi. Microbiol Res 2022; 262:127103. [DOI: 10.1016/j.micres.2022.127103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 06/07/2022] [Accepted: 06/22/2022] [Indexed: 10/17/2022]
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4
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Paschoal D, Costa JL, da Silva EM, da Silva FB, Capelin D, Ometto V, Aricetti JA, Carvalho GG, Pimpinato RF, de Oliveira RF, Carrera E, López-Díaz I, Rossi ML, Tornisielo V, Caldana C, Riano-Pachon DM, Cesarino I, Teixeira PJPL, Figueira A. Infection by Moniliophthora perniciosa reprograms tomato Micro-Tom physiology, establishes a sink, and increases secondary cell wall synthesis. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:3651-3670. [PMID: 35176760 DOI: 10.1093/jxb/erac057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 02/15/2022] [Indexed: 06/14/2023]
Abstract
Witches' broom disease of cacao is caused by the pathogenic fungus Moniliophthora perniciosa. By using tomato (Solanum lycopersicum) cultivar Micro-Tom (MT) as a model system, we investigated the physiological and metabolic consequences of M. perniciosa infection to determine whether symptoms result from sink establishment during infection. Infection of MT by M. perniciosa caused reductions in root biomass and fruit yield, a decrease in leaf gas exchange, and down-regulation of photosynthesis-related genes. The total leaf area and water potential decreased, while ABA levels, water conductance/conductivity, and ABA-related gene expression increased. Genes related to sugar metabolism and those involved in secondary cell wall deposition were up-regulated upon infection, and the concentrations of sugars, fumarate, and amino acids increased. 14C-glucose was mobilized towards infected MT stems, but not in inoculated stems of the MT line overexpressing CYTOKININ OXIDASE-2 (35S::AtCKX2), suggesting a role for cytokinin in establishing a sugar sink. The up-regulation of genes involved in cell wall deposition and phenylpropanoid metabolism in infected MT, but not in 35S::AtCKX2 plants, suggests establishment of a cytokinin-mediated sink that promotes tissue overgrowth with an increase in lignin. Possibly, M. perniciosa could benefit from the accumulation of secondary cell walls during its saprotrophic phase of infection.
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Affiliation(s)
- Daniele Paschoal
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, SP, 13400-970, Brazil
- Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, Piracicaba, SP, 13418-900, Brazil
| | - Juliana L Costa
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, SP, 13400-970, Brazil
| | - Eder M da Silva
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, SP, 13400-970, Brazil
| | - Fábia B da Silva
- Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, Piracicaba, SP, 13418-900, Brazil
| | - Diogo Capelin
- Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, Piracicaba, SP, 13418-900, Brazil
| | - Vitor Ometto
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, SP, 13400-970, Brazil
| | - Juliana A Aricetti
- Laboratório Nacional de Biorrenováveis, Centro Nacional de Pesquisa em Energia e Materiais, Campinas, SP, 13083-100, Brazil
| | - Gabriel G Carvalho
- Instituto de Biociências, Universidade de São Paulo, São Paulo, SP, 05508-090, Brazil
| | - Rodrigo F Pimpinato
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, SP, 13400-970, Brazil
| | - Ricardo F de Oliveira
- Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, Piracicaba, SP, 13418-900, Brazil
| | - Esther Carrera
- Universitat Politècnica de València (UPV), Consejo Superior de Investigaciones Científicas (CSIC), Valencia, Spain
| | - Isabel López-Díaz
- Universitat Politècnica de València (UPV), Consejo Superior de Investigaciones Científicas (CSIC), Valencia, Spain
| | - Mônica L Rossi
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, SP, 13400-970, Brazil
| | - Valdemar Tornisielo
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, SP, 13400-970, Brazil
| | - Camila Caldana
- Max Planck Institute for Molecular Plant Physiology, 14476 Potsdam-Golm, Germany
| | - Diego M Riano-Pachon
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, SP, 13400-970, Brazil
| | - Igor Cesarino
- Instituto de Biociências, Universidade de São Paulo, São Paulo, SP, 05508-090, Brazil
| | - Paulo J P L Teixeira
- Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, Piracicaba, SP, 13418-900, Brazil
| | - Antonio Figueira
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, SP, 13400-970, Brazil
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Dauda WP, Shanmugam V, Tyagi A, Solanke AU, Kumar V, Krishnan SG, Bashyal BM, Aggarwal R. Genome-Wide Identification and Characterisation of Cytokinin-O-Glucosyltransferase (CGT) Genes of Rice Specific to Potential Pathogens. PLANTS (BASEL, SWITZERLAND) 2022; 11:plants11070917. [PMID: 35406897 PMCID: PMC9002877 DOI: 10.3390/plants11070917] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 03/25/2022] [Accepted: 03/25/2022] [Indexed: 05/12/2023]
Abstract
Cytokinin glucosyltransferases (CGTs) are key enzymes of plants for regulating the level and function of cytokinins. In a genomic identification of rice CGTs, 41 genes with the plant secondary product glycosyltransferases (PSPG) motif of 44-amino-acid consensus sequence characteristic of plant uridine diphosphate (UDP)-glycosyltransferases (UGTs) were identified. In-silico physicochemical characterisation revealed that, though the CGTs belong to the same subfamily, they display varying molecular weights, ranging from 19.6 kDa to 59.7 kDa. The proteins were primarily acidic (87.8%) and hydrophilic (58.6%) and were observed to be distributed in the plastids (16), plasma membrane (13), mitochondria (5), and cytosol (4). Phylogenetic analysis of the CGTs revealed that their evolutionary relatedness ranged from 70-100%, and they aligned themselves into two major clusters. In a comprehensive analysis of the available transcriptomics data of rice samples representing different growth stages only the CGT, Os04g25440.1 was significantly expressed at the vegetative stage, whereas 16 other genes were highly expressed only at the reproductive growth stage. On the contrary, six genes, LOC_Os07g30610.1, LOC_Os04g25440.1, LOC_Os07g30620.1, LOC_Os04g25490.1, LOC_Os04g37820.1, and LOC_Os04g25800.1, were significantly upregulated in rice plants inoculated with Rhizoctonia solani (RS), Xoo (Xanthomonas oryzae pv. oryzae) and Mor (Magnaporthe oryzae). In a qRT-PCR analysis of rice sheath tissue susceptible to Rhizoctonia solani, Mor, and Xoo pathogens, compared to the sterile distilled water control, at 24 h post-infection only two genes displayed significant upregulation in response to all the three pathogens: LOC_Os07g30620.1 and LOC_Os04g25820.1. On the other hand, the expression of genes LOC_Os07g30610.1, LOC_Os04g25440, LOC_Os04g25490, and LOC_Os04g25800 were observed to be pathogen-specific. These genes were identified as the candidate-responsive CGT genes and could serve as potential susceptibility genes for facilitating pathogen infection.
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Affiliation(s)
- Wadzani Palnam Dauda
- ICAR-Indian Agricultural Research Institute, New Delhi 110012, India; (W.P.D.); (A.T.); (S.G.K.); (B.M.B.); (R.A.)
- Crop Science Unit, Department of Agronomy, Federal University, Gashua 1005, Nigeria
| | - Veerubommu Shanmugam
- ICAR-Indian Agricultural Research Institute, New Delhi 110012, India; (W.P.D.); (A.T.); (S.G.K.); (B.M.B.); (R.A.)
- Correspondence:
| | - Aditya Tyagi
- ICAR-Indian Agricultural Research Institute, New Delhi 110012, India; (W.P.D.); (A.T.); (S.G.K.); (B.M.B.); (R.A.)
| | - Amolkumar U. Solanke
- ICAR-National Institute for Plant Biotechnology, New Delhi 110012, India; (A.U.S.); (V.K.)
| | - Vishesh Kumar
- ICAR-National Institute for Plant Biotechnology, New Delhi 110012, India; (A.U.S.); (V.K.)
| | - Subbaiyan Gopala Krishnan
- ICAR-Indian Agricultural Research Institute, New Delhi 110012, India; (W.P.D.); (A.T.); (S.G.K.); (B.M.B.); (R.A.)
| | - Bishnu Maya Bashyal
- ICAR-Indian Agricultural Research Institute, New Delhi 110012, India; (W.P.D.); (A.T.); (S.G.K.); (B.M.B.); (R.A.)
| | - Rashmi Aggarwal
- ICAR-Indian Agricultural Research Institute, New Delhi 110012, India; (W.P.D.); (A.T.); (S.G.K.); (B.M.B.); (R.A.)
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Maitra S, Brestic M, Bhadra P, Shankar T, Praharaj S, Palai JB, Shah MMR, Barek V, Ondrisik P, Skalický M, Hossain A. Bioinoculants-Natural Biological Resources for Sustainable Plant Production. Microorganisms 2021; 10:51. [PMID: 35056500 PMCID: PMC8780112 DOI: 10.3390/microorganisms10010051] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Revised: 12/21/2021] [Accepted: 12/23/2021] [Indexed: 11/22/2022] Open
Abstract
Agricultural sustainability is of foremost importance for maintaining high food production. Irresponsible resource use not only negatively affects agroecology, but also reduces the economic profitability of the production system. Among different resources, soil is one of the most vital resources of agriculture. Soil fertility is the key to achieve high crop productivity. Maintaining soil fertility and soil health requires conscious management effort to avoid excessive nutrient loss, sustain organic carbon content, and minimize soil contamination. Though the use of chemical fertilizers have successfully improved crop production, its integration with organic manures and other bioinoculants helps in improving nutrient use efficiency, improves soil health and to some extent ameliorates some of the constraints associated with excessive fertilizer application. In addition to nutrient supplementation, bioinoculants have other beneficial effects such as plant growth-promoting activity, nutrient mobilization and solubilization, soil decontamination and/or detoxification, etc. During the present time, high energy based chemical inputs also caused havoc to agriculture because of the ill effects of global warming and climate change. Under the consequences of climate change, the use of bioinputs may be considered as a suitable mitigation option. Bioinoculants, as a concept, is not something new to agricultural science, however; it is one of the areas where consistent innovations have been made. Understanding the role of bioinoculants, the scope of their use, and analysing their performance in various environments are key to the successful adaptation of this technology in agriculture.
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Affiliation(s)
- Sagar Maitra
- Department of Agronomy, M.S. Swaminathan School of Agriculture, Centurion University of Technology and Management, Paralakheundi 761 211, India; (S.M.); (T.S.); (S.P.); (J.B.P.)
| | - Marian Brestic
- Department of Plant Physiology, Slovak University of Agriculture, Tr. A. Hlinku 2, 949 01 Nitra, Slovakia;
- Department of Botany and Plant Physiology, Faculty of Agrobiology, Food, and Natural Resources, Czech University of Life Sciences Prague, Kamycka 129, 165 00 Prague, Czech Republic;
| | - Preetha Bhadra
- Department of Biotechnology, M.S. Swaminathan School of Agriculture, Centurion University of Technology and Management, Paralakheundi 761 211, India;
| | - Tanmoy Shankar
- Department of Agronomy, M.S. Swaminathan School of Agriculture, Centurion University of Technology and Management, Paralakheundi 761 211, India; (S.M.); (T.S.); (S.P.); (J.B.P.)
| | - Subhashisa Praharaj
- Department of Agronomy, M.S. Swaminathan School of Agriculture, Centurion University of Technology and Management, Paralakheundi 761 211, India; (S.M.); (T.S.); (S.P.); (J.B.P.)
| | - Jnana Bharati Palai
- Department of Agronomy, M.S. Swaminathan School of Agriculture, Centurion University of Technology and Management, Paralakheundi 761 211, India; (S.M.); (T.S.); (S.P.); (J.B.P.)
| | | | - Viliam Barek
- Department of Water Resources and Environmental Engineering, Faculty of Horticulture and Landscape Engineering, Slovak University of Agriculture, Tr. A. Hlinku 2, 949 01 Nitra, Slovakia;
| | - Peter Ondrisik
- Department of Plant Physiology, Slovak University of Agriculture, Tr. A. Hlinku 2, 949 01 Nitra, Slovakia;
| | - Milan Skalický
- Department of Botany and Plant Physiology, Faculty of Agrobiology, Food, and Natural Resources, Czech University of Life Sciences Prague, Kamycka 129, 165 00 Prague, Czech Republic;
| | - Akbar Hossain
- Bangladesh Wheat and Maize Research Institute, Dinajpur 5200, Bangladesh;
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Dabravolski SA, Isayenkov SV. Evolution of the Cytokinin Dehydrogenase (CKX) Domain. J Mol Evol 2021; 89:665-677. [PMID: 34757471 DOI: 10.1007/s00239-021-10035-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Accepted: 10/30/2021] [Indexed: 01/05/2023]
Abstract
Plant hormone cytokinins are important regulators of plant development, response to environmental stresses and interplay with other plant hormones. Cytokinin dehydrogenases (CKXs) are proteins responsible for the irreversible break-down of cytokinins to the adenine and aldehyde. Even though plant CKXs have been extensively studied, homologous proteins from other taxa remain mainly uncharacterised. Here we present our study on the molecular evolution and divergence of the CKX from bacteria, fungi, amoeba and viridiplantae. Although CKXs are present in eukaryotes and prokaryotes, they are missing in algae and metazoan taxa. The prevalent domain architecture consists of the FAD-binding and cytokinin binding domains, whereas some bacteria appear to have only cytokinin binding domain proteins. The CKXs play important role in the various aspects of plant life including control of plant development, response to biotic and abiotic stress, influence nutrition. Results of our study suggested that CKX originates from the FAD-linked C-terminal oxidase and has a defence-oriented function. The obtained results significantly extend the current understanding of the cytokinin dehydrogenases structure-function from the relationship to homologues from other taxa and provide a starting point baseline for their future functional characterization.
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Affiliation(s)
- Siarhei A Dabravolski
- Department of Clinical Diagnostics, Vitebsk State Academy of Veterinary Medicine [UO VGAVM], Dovatora str. 7/11, 21002, Vitebsk, Belarus
| | - Stanislav V Isayenkov
- International Research Centre for Environmental Membrane Biology, Foshan University, Foshan, China.
- Department of Plant Food Products and Biofortification, Institute of Food Biotechnology and Genomics, NAS of Ukraine, Osipovskogo str., 2a, Kyiv-123, Kyiv, 04123, Ukraine.
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Lopez JAV, Nogawa T, Yoshida K, Futamura Y, Osada H. 2-Methylthio-N7-methyl-cis-zeatin, a new antimalarial natural product isolated from a Streptomyces culture. Biosci Biotechnol Biochem 2021; 86:31-36. [PMID: 34734225 DOI: 10.1093/bbb/zbab192] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 10/26/2021] [Indexed: 11/14/2022]
Abstract
2-Methylthio-N7-methyl-cis-zeatin (1) was isolated from the culture broth of Streptomyces sp. 80H647 along with two known purine derivatives, 5'-methylthioinosine (2) and AT-265 (dealanylascamycin, 3). The structure elucidation of compound 1 was accomplished by HRMS and NMR analyses. It inhibited the growth of Plasmodium falciparum 3D7 with a GI50 of 2.4 μM and had no effect on the growth of Arabidopsis at 2 μM. This is the first report of an N7-methylated zeatin-type natural product from Streptomyces and as an antimalarial compound.
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Affiliation(s)
- Julius Adam V Lopez
- RIKEN Center for Sustainable Resource Science, Chemical Biology Research Group, 2-1 Hirosawa, Wako, Saitama, Japan
| | - Toshihiko Nogawa
- RIKEN Center for Sustainable Resource Science, Chemical Biology Research Group, 2-1 Hirosawa, Wako, Saitama, Japan
| | - Kazuko Yoshida
- RIKEN Center for Sustainable Resource Science, Chemical Biology Research Group, 2-1 Hirosawa, Wako, Saitama, Japan
| | - Yushi Futamura
- RIKEN Center for Sustainable Resource Science, Chemical Biology Research Group, 2-1 Hirosawa, Wako, Saitama, Japan
| | - Hiroyuki Osada
- RIKEN Center for Sustainable Resource Science, Chemical Biology Research Group, 2-1 Hirosawa, Wako, Saitama, Japan
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Singh D, Singla-Pareek SL, Pareek A. Two-component signaling system in plants: interaction network and specificity in response to stress and hormones. PLANT CELL REPORTS 2021; 40:2037-2046. [PMID: 34109469 DOI: 10.1007/s00299-021-02727-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 05/31/2021] [Indexed: 06/12/2023]
Abstract
Plants are exposed to various environmental challenges that can hamper their growth, development, and productivity. Being sedentary, plants cannot escape from these unfavorable environmental conditions and have evolved various signaling cascades to endure them. The two-component signaling (TCS) system is one such essential signaling circuitry present in plants regulating responses against multiple abiotic and biotic stresses. It is among the most ancient and evolutionary conserved signaling pathways in plants, which include membrane-bound histidine kinases (HKs), cytoplasmic histidine phosphotransfer proteins (Hpts), and nuclear or cytoplasmic response regulators (RRs). At the same time, TCS also involved in many signaling circuitries operative in plants in response to diverse hormones. These plant growth hormones play a significant role in diverse physiological and developmental processes, and their contribution to plant stress responses is coming up in a big way. Therefore, it is intriguing to know how TCS and various plant growth regulators, along with the key transcription factors, directly or indirectly control the responses of plants towards diverse stresses. The present review attempts to explore this relationship, hoping that this knowledge will contribute towards developing crop plants with enhanced climate resilience.
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Affiliation(s)
- Deepti Singh
- Stress Physiology and Molecular Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, Delhi, India
| | - Sneh Lata Singla-Pareek
- Plant Stress Biology, International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, Delhi, India
| | - Ashwani Pareek
- Stress Physiology and Molecular Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, Delhi, India.
- National Agri-Food Biotechnology Institute, Sahibzada Ajit Singh Nagar, Punjab, 140306, India.
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Pereyra-Bistraín LI, Ovando-Vázquez C, Rougon-Cardoso A, Alpuche-Solís ÁG. Comparative RNA-Seq Analysis Reveals Potentially Resistance-Related Genes in Response to Bacterial Canker of Tomato. Genes (Basel) 2021; 12:genes12111745. [PMID: 34828351 PMCID: PMC8618811 DOI: 10.3390/genes12111745] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Revised: 10/22/2021] [Accepted: 10/26/2021] [Indexed: 12/13/2022] Open
Abstract
Tomato is one of the most important crops for human consumption. Its production is affected by the actinomycete Clavibacter michiganensis subsp. michiganensis (Cmm), one of the most devastating bacterial pathogens of this crop. Several wild tomato species represent a source of natural resistance to Cmm. Here, we contrasted the transcriptomes of the resistant wild tomato species Solanum arcanum LA2157 and the susceptible species Solanum lycopersicum cv. Ailsa Craig, during the first 24 h of challenge with Cmm. We used three analyses approaches which demonstrated to be complementary: mapping to S. lycopersicum reference genome SL3.0; semi de novo transcriptome assembly; and de novo transcriptome assembly. In a global context, transcriptional changes seem to be similar between both species, although there are some specific genes only upregulated in S. arcanum during Cmm interaction, suggesting that the resistance regulatory mechanism probably diverged during the domestication process. Although S. lycopersicum showed enriched functional groups related to defense, S. arcanum displayed a higher number of induced genes related to bacterial, oomycete, and fungal defense at the first few hours of interaction. This study revealed genes that may contribute to the resistance phenotype in the wild tomato species, such as those that encode for a polyphenol oxidase E, diacyl glycerol kinase, TOM1-like protein 6, and an ankyrin repeat-containing protein, among others. This work will contribute to a better understanding of the defense mechanism against Cmm, and the development of new control methods.
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Affiliation(s)
- Leonardo I. Pereyra-Bistraín
- División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica A.C., San Luis Potosí 78216, Mexico;
| | - Cesaré Ovando-Vázquez
- Centro Nacional de Supercómputo, Instituto Potosino de Investigación Científica y Tecnológica A.C., Consejo Nacional de Ciencia y Tecnología, San Luis Potosí 78216, Mexico;
| | - Alejandra Rougon-Cardoso
- Laboratory of Agrigenomic Sciences, Universidad Nacional Autónoma de México, ENES-León, León 37689, Mexico
- Correspondence: (A.R.-C.); (Á.G.A.-S.); Tel.: +52-(444)-834-2000 (Á.G.A.-S.)
| | - Ángel G. Alpuche-Solís
- División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica A.C., San Luis Potosí 78216, Mexico;
- Correspondence: (A.R.-C.); (Á.G.A.-S.); Tel.: +52-(444)-834-2000 (Á.G.A.-S.)
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11
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Wu D, Wang L, Zhang Y, Bai L, Yu F. Emerging roles of pathogen-secreted host mimics in plant disease development. Trends Parasitol 2021; 37:1082-1095. [PMID: 34627670 DOI: 10.1016/j.pt.2021.09.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 09/17/2021] [Accepted: 09/21/2021] [Indexed: 11/19/2022]
Abstract
Plant pathogens and parasites use multiple virulence factors to successfully infect plants. While most plant-pathogen interaction studies focus on pathogen effectors and their functions in suppressing plant immunity or interfering with normal cellular processes, other virulence factors likely also contribute. Here we highlight another important strategy used by pathogens to promote virulence: secretion of mimics of host molecules, including peptides, phytohormones, and small RNAs, which play diverse roles in plant development and stress responses. Pathogen-secreted mimics hijack the host endogenous signaling pathways, thereby modulating host cellular functions to the benefit of the pathogen and promoting infection. Understanding the mechanisms of pathogen-secreted host mimics will expand our knowledge of host-pathogen coevolution and interactions, while providing new targets for plant disease control.
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Affiliation(s)
- Dousheng Wu
- Hunan Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha, 410082, China
| | - Lifeng Wang
- Hunan Weed Science Key Laboratory, Hunan Academy of Agricultural Sciences, Changsha, 410125, China
| | - Yong Zhang
- College of Resources and Environment, Southwest University, Beibei, Chongqing, 400715, China
| | - Lianyang Bai
- Hunan Weed Science Key Laboratory, Hunan Academy of Agricultural Sciences, Changsha, 410125, China.
| | - Feng Yu
- Hunan Key Laboratory of Plant Functional Genomics and Developmental Regulation, College of Biology, Hunan University, Changsha, 410082, China.
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12
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Nguyen HN, Nguyen TQ, Kisiala AB, Emery RJN. Beyond transport: cytokinin ribosides are translocated and active in regulating the development and environmental responses of plants. PLANTA 2021; 254:45. [PMID: 34365553 DOI: 10.1007/s00425-021-03693-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 08/01/2021] [Indexed: 06/13/2023]
Abstract
Riboside type cytokinins are key components in cytokinin metabolism, transport, and sensitivity, making them important functional signals in plant growth and development and environmental stress responses. Cytokinin (CKs) are phytohormones that regulate multiple processes in plants and are critical for agronomy, as they are involved in seed filling and plant responses to biotic and abiotic stress. Among the over 30 identified CKs, there is uncertainty about the roles of many of the individual CK structural forms. Cytokinin free bases (CKFBs), have been studied in great detail, but, by comparison, roles of riboside-type CKs (CKRs) in CK metabolism and associated signaling pathways and their distal impacts on plant physiology remain largely unknown. Here, recent findings on CKR abundance, transport and localization, are summarized, and their importance in planta is discussed. The history of CKR analyses is reviewed, in the context of the determination of CK metabolic pathways, and research on CKR affinity for CK receptors, all of which yield essential insights into their functions. Recent studies suggest that CKR forms are a lot more than a group of transport CKs and, beyond this, they play important roles in plant development and responses to environmental stress. In this context, this review discusses the involvement of CKRs in plant development, and highlight the less anticipated functions of CKRs in abiotic stress tolerance. Based on this, possible mechanisms for CKR modes of action are proposed and experimental approaches to further uncover their roles and future biotechnological applications are suggested.
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Affiliation(s)
- Hai Ngoc Nguyen
- Department of Biology, Trent University, Peterborough, ON, K9L 0G2, Canada.
| | - Thien Quoc Nguyen
- Department of Biology, Trent University, Peterborough, ON, K9L 0G2, Canada
| | - Anna B Kisiala
- Department of Biology, Trent University, Peterborough, ON, K9L 0G2, Canada
| | - R J Neil Emery
- Department of Biology, Trent University, Peterborough, ON, K9L 0G2, Canada
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13
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Nguyen HN, Lai N, Kisiala AB, Emery RJN. Isopentenyltransferases as master regulators of crop performance: their function, manipulation, and genetic potential for stress adaptation and yield improvement. PLANT BIOTECHNOLOGY JOURNAL 2021; 19:1297-1313. [PMID: 33934489 PMCID: PMC8313133 DOI: 10.1111/pbi.13603] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 03/23/2021] [Accepted: 04/11/2021] [Indexed: 05/27/2023]
Abstract
Isopentenyltransferase (IPT) in plants regulates a rate-limiting step of cytokinin (CTK) biosynthesis. IPTs are recognized as key regulators of CTK homeostasis and phytohormone crosstalk in both biotic and abiotic stress responses. Recent research has revealed the regulatory function of IPTs in gene expression and metabolite profiles including source-sink modifications, energy metabolism, nutrient allocation and storage, stress defence and signalling pathways, protein synthesis and transport, and membrane transport. This suggests that IPTs play a crucial role in plant growth and adaptation. In planta studies of IPT-driven modifications indicate that, at a physiological level, IPTs improve stay-green characteristics, delay senescence, reduce stress-induced oxidative damage and protect photosynthetic machinery. Subsequently, these improvements often manifest as enhanced or stabilized crop yields and this is especially apparent under environmental stress. These mechanisms merit consideration of the IPTs as 'master regulators' of core cellular metabolic pathways, thus adjusting plant homeostasis/adaptive responses to altered environmental stresses, to maximize yield potential. If their expression can be adequately controlled, both spatially and temporally, IPTs can be a key driver for seed yield. In this review, we give a comprehensive overview of recent findings on how IPTs influence plant stress physiology and yield, and we highlight areas for future research.
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Affiliation(s)
| | - Nhan Lai
- School of BiotechnologyVietnam National UniversityHo Chi Minh CityVietnam
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14
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Costa JL, Paschoal D, da Silva EM, Silva JS, do Carmo RM, Carrera E, López-Díaz I, Rossi ML, Freschi L, Mieczkowski P, Peres LEP, Teixeira PJPL, Figueira A. Moniliophthora perniciosa, the causal agent of witches' broom disease of cacao, interferes with cytokinin metabolism during infection of Micro-Tom tomato and promotes symptom development. THE NEW PHYTOLOGIST 2021; 231:365-381. [PMID: 33826751 DOI: 10.1111/nph.17386] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Accepted: 03/25/2021] [Indexed: 06/12/2023]
Abstract
Moniliophthora perniciosa causes witches' broom disease of cacao and inflicts symptoms suggestive of hormonal imbalance. We investigated whether infection of the tomato (Solanum lycopersicum) model system Micro-Tom (MT) by the Solanaceae (S)-biotype of Moniliophthora perniciosa, which causes stem swelling and hypertrophic growth of axillary shoots, results from changes in host cytokinin metabolism. Inoculation of an MT-transgenic line that overexpresses the Arabidopsis CYTOKININ OXIDASE-2 gene (35S::AtCKX2) resulted in a reduction in disease incidence and stem diameter. RNA-sequencing analysis of infected MT and 35S::AtCKX2 revealed the activation of cytokinin-responsive marker genes when symptoms were conspicuous. The expression of an Moniliophthora perniciosa tRNA-ISOPENTENYL-TRANSFERASE suggests the production of isopentenyladenine (iP), detected in mycelia grown in vitro. Inoculated MT stems showed higher levels of dihydrozeatin and trans-zeatin but not iP. The application of benzyladenine induced symptoms similar to infection, whereas applying the cytokinin receptor inhibitors LGR-991 and PI55 decreased symptoms. Moniliophthora perniciosa produces iP that might contribute to cytokinin synthesis by the host, which results in vascular and cortex enlargement, axillary shoot outgrowth, reduction in root biomass and an increase in fruit locule number. This strategy may be associated with the manipulation of sink establishment to favour infection by the fungus.
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Affiliation(s)
- Juliana L Costa
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Av. Centenário 303, Piracicaba, SP, 13400-970, Brazil
| | - Daniele Paschoal
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Av. Centenário 303, Piracicaba, SP, 13400-970, Brazil
- Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, Av. Pádua Dias 9, Piracicaba, SP, 13418-900, Brazil
| | - Eder M da Silva
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Av. Centenário 303, Piracicaba, SP, 13400-970, Brazil
| | - Jamille S Silva
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Av. Centenário 303, Piracicaba, SP, 13400-970, Brazil
- Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, Av. Pádua Dias 9, Piracicaba, SP, 13418-900, Brazil
| | - Rafael M do Carmo
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Av. Centenário 303, Piracicaba, SP, 13400-970, Brazil
| | - Esther Carrera
- Instituto de Biología Molecular y Celular de Plantas, Universitat Politècnica de València (UPV), Consejo Superior de Investigaciones Científicas (CSIC), Ingeniero Fausto Elío s/n, Valencia, 46022, Spain
| | - Isabel López-Díaz
- Instituto de Biología Molecular y Celular de Plantas, Universitat Politècnica de València (UPV), Consejo Superior de Investigaciones Científicas (CSIC), Ingeniero Fausto Elío s/n, Valencia, 46022, Spain
| | - Mônica L Rossi
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Av. Centenário 303, Piracicaba, SP, 13400-970, Brazil
| | - Luciano Freschi
- Instituto de Biociências, Universidade de São Paulo, R. do Matão 321, São Paulo, SP, 05508-090, Brazil
| | - Piotr Mieczkowski
- University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599-7264, USA
| | - Lazaro E P Peres
- Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, Av. Pádua Dias 9, Piracicaba, SP, 13418-900, Brazil
| | - Paulo J P L Teixeira
- Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, Av. Pádua Dias 9, Piracicaba, SP, 13418-900, Brazil
- University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599-7264, USA
| | - Antonio Figueira
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Av. Centenário 303, Piracicaba, SP, 13400-970, Brazil
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15
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Frébortová J, Frébort I. Biochemical and Structural Aspects of Cytokinin Biosynthesis and Degradation in Bacteria. Microorganisms 2021; 9:microorganisms9061314. [PMID: 34208724 PMCID: PMC8234997 DOI: 10.3390/microorganisms9061314] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 06/11/2021] [Accepted: 06/14/2021] [Indexed: 11/16/2022] Open
Abstract
It has been known for quite some time that cytokinins, hormones typical of plants, are also produced and metabolized in bacteria. Most bacteria can only form the tRNA-bound cytokinins, but there are examples of plant-associated bacteria, both pathogenic and beneficial, that actively synthesize cytokinins to interact with their host. Similar to plants, bacteria produce diverse cytokinin metabolites, employing corresponding metabolic pathways. The identification of genes encoding the enzymes involved in cytokinin biosynthesis and metabolism facilitated their detailed characterization based on both classical enzyme assays and structural approaches. This review summarizes the present knowledge on key enzymes involved in cytokinin biosynthesis, modifications, and degradation in bacteria, and discusses their catalytic properties in relation to the presence of specific amino acid residues and protein structure.
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16
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Abstract
Covering: up to mid-2020 Terpenoids, also called isoprenoids, are the largest and most structurally diverse family of natural products. Found in all domains of life, there are over 80 000 known compounds. The majority of characterized terpenoids, which include some of the most well known, pharmaceutically relevant, and commercially valuable natural products, are produced by plants and fungi. Comparatively, terpenoids of bacterial origin are rare. This is counter-intuitive to the fact that recent microbial genomics revealed that almost all bacteria have the biosynthetic potential to create the C5 building blocks necessary for terpenoid biosynthesis. In this review, we catalogue terpenoids produced by bacteria. We collected 1062 natural products, consisting of both primary and secondary metabolites, and classified them into two major families and 55 distinct subfamilies. To highlight the structural and chemical space of bacterial terpenoids, we discuss their structures, biosynthesis, and biological activities. Although the bacterial terpenome is relatively small, it presents a fascinating dichotomy for future research. Similarities between bacterial and non-bacterial terpenoids and their biosynthetic pathways provides alternative model systems for detailed characterization while the abundance of novel skeletons, biosynthetic pathways, and bioactivies presents new opportunities for drug discovery, genome mining, and enzymology.
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Affiliation(s)
- Jeffrey D Rudolf
- Department of Chemistry, University of Florida, Gainesville, Florida 32611, USA.
| | - Tyler A Alsup
- Department of Chemistry, University of Florida, Gainesville, Florida 32611, USA.
| | - Baofu Xu
- Department of Chemistry, University of Florida, Gainesville, Florida 32611, USA.
| | - Zining Li
- Department of Chemistry, University of Florida, Gainesville, Florida 32611, USA.
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17
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Nedvěd D, Hošek P, Klíma P, Hoyerová K. Differential Subcellular Distribution of Cytokinins: How Does Membrane Transport Fit into the Big Picture? Int J Mol Sci 2021; 22:3428. [PMID: 33810428 PMCID: PMC8037549 DOI: 10.3390/ijms22073428] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 03/02/2021] [Accepted: 03/22/2021] [Indexed: 12/17/2022] Open
Abstract
Cytokinins are a class of phytohormones, signalling molecules specific to plants. They act as regulators of diverse physiological processes in complex signalling pathways. It is necessary for plants to continuously regulate cytokinin distribution among different organs, tissues, cells, and compartments. Such regulatory mechanisms include cytokinin biosynthesis, metabolic conversions and degradation, as well as cytokinin membrane transport. In our review, we aim to provide a thorough picture of the latter. We begin by summarizing cytokinin structures and physicochemical properties. Then, we revise the elementary thermodynamic and kinetic aspects of cytokinin membrane transport. Next, we review which membrane-bound carrier proteins and protein families recognize cytokinins as their substrates. Namely, we discuss the families of "equilibrative nucleoside transporters" and "purine permeases", which translocate diverse purine-related compounds, and proteins AtPUP14, AtABCG14, AtAZG1, and AtAZG2, which are specific to cytokinins. We also address long-distance cytokinin transport. Putting all these pieces together, we finally discuss cytokinin distribution as a net result of these processes, diverse in their physicochemical nature but acting together to promote plant fitness.
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Affiliation(s)
- Daniel Nedvěd
- The Czech Academy of Sciences, Institute of Experimental Botany, 165 02 Prague, Czech Republic; (D.N.); (P.H.)
- Department of Biochemistry, Faculty of Science, Charles University, 128 00 Prague, Czech Republic
| | - Petr Hošek
- The Czech Academy of Sciences, Institute of Experimental Botany, 165 02 Prague, Czech Republic; (D.N.); (P.H.)
| | - Petr Klíma
- The Czech Academy of Sciences, Institute of Experimental Botany, 165 02 Prague, Czech Republic; (D.N.); (P.H.)
| | - Klára Hoyerová
- The Czech Academy of Sciences, Institute of Experimental Botany, 165 02 Prague, Czech Republic; (D.N.); (P.H.)
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18
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Abstract
Phytohormones mediate plant development and responses to stresses caused by biotic agents or abiotic factors. The functions of phytohormones in responses to viral infection have been intensively studied, and the emerging picture of complex mechanisms provides insights into the roles that phytohormones play in defense regulation as a whole. These hormone signaling pathways are not simple linear or isolated cascades, but exhibit crosstalk with each other. Here, we summarized the current understanding of recent advances for the classical defense hormones salicylic acid (SA), jasmonic acid (JA), and ethylene (ET) and also the roles of abscisic acid (ABA), auxin, gibberellic acid (GA), cytokinins (CKs), and brassinosteroids (BRs) in modulating plant–virus interactions.
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19
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Li B, Wang R, Wang S, Zhang J, Chang L. Diversified Regulation of Cytokinin Levels and Signaling During Botrytis cinerea Infection in Arabidopsis. FRONTIERS IN PLANT SCIENCE 2021; 12:584042. [PMID: 33643340 PMCID: PMC7902887 DOI: 10.3389/fpls.2021.584042] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 01/06/2021] [Indexed: 05/28/2023]
Abstract
Cytokinins (CKs) can modulate plant immunity to various pathogens, but how CKs are involved in plant defense responses to the necrotrophic pathogen Botrytis cinerea is still unknown. Here, we found that B. cinerea infection induced transcriptional changes in multiple genes involved in the biosynthesis, degradation, and signaling of CKs, as well as their contents, in pathogen-infected Arabidopsis leaves. Among the CKs, the gene expression of CYTOKININ OXIDASE/DEHYDROGENASE 5 (CKX5) was remarkably induced in the local infected leaves and the distant leaves of the same plant without pathogen inoculation. Cis-zeatin (cZ) and its riboside (cZR) accumulated considerably in infected leaves, suggesting an important role of the cis-zeatin type of CKs in the plant response to B. cinerea. Cytokinin double-receptor mutants were more susceptible to B. cinerea infection, whereas an exogenous CK treatment enhanced the expression levels of defense-related genes and of jasmonic acid (JA) and ethylene (ET), but not salicylic acid (SA), resulting in higher resistance of Arabidopsis to B. cinerea. Investigation of CK responses to B. cinerea infection in the JA biosynthesis mutant, jar1-1, and ET-insensitive mutant, ein2-1, showed that CK signaling and levels of CKs, namely, those of isopentenyladenine (iP), isopentenyladenine riboside (iPR), and trans-zeatin (tZ), were enhanced in jar1-1-infected leaves. By contrast, reductions in iP, iPR, tZ, and tZ riboside (tZR) as well as cZR contents occurred in ein2-1-infected leaves, whose transcript levels of CK signaling genes were likewise differentially regulated. The Arabidopsis Response Regulator 5 (ARR5) gene was upregulated in infected leaves of ein2-1 whereas another type-A response regulator, ARR16, was significantly downregulated, suggesting the existence of a complex regulation of CK signaling via the ET pathway. Accumulation of the cis-zeatin type of CKs in B. cinerea-infected leaves depended on ET but not JA pathways. Collectively, our findings provide evidence that CK responds to B. cinerea infection in a variety of ways that are differently modulated by JA and ET pathways in Arabidopsis.
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Affiliation(s)
- Beibei Li
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, China
| | - Ruolin Wang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, China
| | - Shiya Wang
- School of Biology and Agricultural Resources, Huanggang Normal University, Huanggang, China
| | - Jiang Zhang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, China
| | - Ling Chang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, China
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20
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The Hulks and the Deadpools of the Cytokinin Universe: A Dual Strategy for Cytokinin Production, Translocation, and Signal Transduction. Biomolecules 2021; 11:biom11020209. [PMID: 33546210 PMCID: PMC7913349 DOI: 10.3390/biom11020209] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 01/27/2021] [Accepted: 01/28/2021] [Indexed: 02/06/2023] Open
Abstract
Cytokinins are plant hormones, derivatives of adenine with a side chain at the N6-position. They are involved in many physiological processes. While the metabolism of trans-zeatin and isopentenyladenine, which are considered to be highly active cytokinins, has been extensively studied, there are others with less obvious functions, such as cis-zeatin, dihydrozeatin, and aromatic cytokinins, which have been comparatively neglected. To help explain this duality, we present a novel hypothesis metaphorically comparing various cytokinin forms, enzymes of CK metabolism, and their signalling and transporter functions to the comics superheroes Hulk and Deadpool. Hulk is a powerful but short-lived creation, whilst Deadpool presents a more subtle and enduring force. With this dual framework in mind, this review compares different cytokinin metabolites, and their biosynthesis, translocation, and sensing to illustrate the different mechanisms behind the two CK strategies. This is put together and applied to a plant developmental scale and, beyond plants, to interactions with organisms of other kingdoms, to highlight where future study can benefit the understanding of plant fitness and productivity.
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21
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Dolzblasz A, Banasiak A, Vereecke D. A sustained CYCLINB1;1 and STM expression in the neoplastic tissues induced by Rhodococcus fascians on Arabidopsis underlies the persistence of the leafy gall structure. PLANT SIGNALING & BEHAVIOR 2020; 15:1816320. [PMID: 32897774 PMCID: PMC7676816 DOI: 10.1080/15592324.2020.1816320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 08/21/2020] [Accepted: 08/25/2020] [Indexed: 06/11/2023]
Abstract
is a gram-positive phytopathogen that infects a wide range of plant species. The actinomycete induces the formation of neoplastic growths, termed leafy galls, that consist of a gall body covered by small shoots of which the outgrowth is arrested due to an extreme form of apical dominance. In our previous work, we demonstrated that in the developing gall, auxin drives the transdifferentiation of parenchyma cells into vascular elements. In this work, with the use of transgenic Arabidopsis thaliana plants carrying molecular reporters for cell division (pCYCB1;1:GUS) and meristematic activity (pSTM:GUS), we analyzed the fate of cells within the leafy gall. Our results indicate that the size of the gall body is determined by ongoing mitotic cell divisions as illustrated by strong CYCB1;1 expression combined with the de novo formation of new meristematic areas triggered by STM expression. The shoot meristems that develop in the peripheral parts of the gall are originating from high ectopic STM expression. Altogether the presented data provide further insight into the cellular events that accompany the development of leafy galls in response to R. fascians infection.
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Affiliation(s)
- Alicja Dolzblasz
- Department of Plant Developmental Biology, Faculty of Biological Sciences, Institute of Experimental Biology, University of Wroclaw, Wrocław, Poland
| | - Alicja Banasiak
- Department of Plant Developmental Biology, Faculty of Biological Sciences, Institute of Experimental Biology, University of Wroclaw, Wrocław, Poland
| | - Danny Vereecke
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
- Department of Entomology, Plant Pathology, and Weed Sciences, New Mexico State University, NM, USA
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22
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Gibb M, Kisiala AB, Morrison EN, Emery RJN. The Origins and Roles of Methylthiolated Cytokinins: Evidence From Among Life Kingdoms. Front Cell Dev Biol 2020; 8:605672. [PMID: 33240900 PMCID: PMC7680852 DOI: 10.3389/fcell.2020.605672] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Accepted: 10/19/2020] [Indexed: 12/24/2022] Open
Abstract
Cytokinins (CKs) are a group of adenine-derived, small signaling molecules of crucial importance for growth and multiple developmental processes in plants. Biological roles of classical CKs: isopentenyladenine (iP), trans and cis isomers of zeatin (tZ, cZ), and dihydrozeatin, have been studied extensively and their functions are well defined in many aspects of plant physiology. In parallel, extensive knowledge exists for genes involved in tRNA modifications that lead to the production of tRNA-bound methylthiolated CKs, especially in bacterial and mammalian systems. However, not much is known about the origins, fates, and possible functions of the unbound methylthiolated CKs (2MeS-CKs) in biological systems. 2MeS-CKs are the free base or riboside derivatives of iP or Z-type CKs, modified by the addition of a thiol group (–SH) at position 2 of the adenine ring that is subsequently methylated. Based on the evidence to date, these distinctive CK conjugates are derived exclusively via the tRNA degradation pathway. This review summarizes the knowledge on the probable steps involved in the biosynthesis of unbound 2MeS-CKs across diverse kingdoms of life. Furthermore, it provides examples of CK profiles of organisms from which the presence of 2MeS-CKs have been detected and confirms a close association and balance between the production of classical CKs and 2MeS-CKs. Finally, it discusses available reports regarding the possible physiological functions of 2MeS-CKs in different biological systems.
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Affiliation(s)
- Maya Gibb
- Department of Biology, Trent University, Peterborough, ON, Canada
| | - Anna B Kisiala
- Department of Biology, Trent University, Peterborough, ON, Canada
| | - Erin N Morrison
- Department of Biology, Trent University, Peterborough, ON, Canada
| | - R J Neil Emery
- Department of Biology, Trent University, Peterborough, ON, Canada
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Plant-Growth-Promoting Bacteria Mitigating Soil Salinity Stress in Plants. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10207326] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Soil deterioration has led to problems with the nutrition of the world’s population. As one of the most serious stressors, soil salinization has a negative effect on the quantity and quality of agricultural production, drawing attention to the need for environmentally friendly technologies to overcome the adverse effects. The use of plant-growth-promoting bacteria (PGPB) can be a key factor in reducing salinity stress in plants as they are already introduced in practice. Plants having halotolerant PGPB in their root surroundings improve in diverse morphological, physiological, and biochemical aspects due to their multiple plant-growth-promoting traits. These beneficial effects are related to the excretion of bacterial phytohormones and modulation of their expression, improvement of the availability of soil nutrients, and the release of organic compounds that modify plant rhizosphere and function as signaling molecules, thus contributing to the plant’s salinity tolerance. This review aims to elucidate mechanisms by which PGPB are able to increase plant tolerance under soil salinity.
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24
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Gupta R, Pizarro L, Leibman‐Markus M, Marash I, Bar M. Cytokinin response induces immunity and fungal pathogen resistance, and modulates trafficking of the PRR LeEIX2 in tomato. MOLECULAR PLANT PATHOLOGY 2020; 21:1287-1306. [PMID: 32841497 PMCID: PMC7488468 DOI: 10.1111/mpp.12978] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 06/29/2020] [Accepted: 06/29/2020] [Indexed: 05/26/2023]
Abstract
Plant immunity is often defined by the immunity hormones: salicylic acid (SA), jasmonic acid (JA), and ethylene (ET). These hormones are well known for differentially regulating defence responses against pathogens. In recent years, the involvement of other plant growth hormones such as auxin, gibberellic acid, abscisic acid, and cytokinins (CKs) in biotic stresses has been recognized. Previous reports have indicated that endogenous and exogenous CK treatment can result in pathogen resistance. We show here that CK induces systemic immunity in tomato (Solanum lycopersicum), modulating cellular trafficking of the pattern recognition receptor (PRR) LeEIX2, which mediates immune responses to Xyn11 family xylanases, and promoting resistance to Botrytis cinerea and Oidium neolycopersici in an SA- and ET-dependent mechanism. CK perception within the host underlies its protective effect. Our results support the notion that CK promotes pathogen resistance by inducing immunity in the host.
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Affiliation(s)
- Rupali Gupta
- Department of Plant Pathology and Weed ResearchInstitute of Plant ProtectionAgricultural Research OrganizationRishon LeZionIsrael
| | - Lorena Pizarro
- Department of Plant Pathology and Weed ResearchInstitute of Plant ProtectionAgricultural Research OrganizationRishon LeZionIsrael
- School of Plant Sciences and Food SecurityTel Aviv UniversityTel AvivIsrael
- Present address:
Institute of Agri‐food, Animal and Environmental SciencesUniversidad de O'HigginsChile
| | - Meirav Leibman‐Markus
- Department of Plant Pathology and Weed ResearchInstitute of Plant ProtectionAgricultural Research OrganizationRishon LeZionIsrael
| | - Iftah Marash
- Department of Plant Pathology and Weed ResearchInstitute of Plant ProtectionAgricultural Research OrganizationRishon LeZionIsrael
- School of Plant Sciences and Food SecurityTel Aviv UniversityTel AvivIsrael
| | - Maya Bar
- Department of Plant Pathology and Weed ResearchInstitute of Plant ProtectionAgricultural Research OrganizationRishon LeZionIsrael
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25
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Oshchepkov MS, Kalistratova AV, Savelieva EM, Romanov GA, Bystrova NA, Kochetkov KA. Natural and synthetic cytokinins and their applications in biotechnology, agrochemistry and medicine. RUSSIAN CHEMICAL REVIEWS 2020. [DOI: 10.1070/rcr4921] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The review is devoted to cytokinins — classical plant hormones known for more than six decades. Nevertheless, different aspects of the action of cytokinins are still being investigated. Relevant studies produced interesting, often unexpected, results, which cast doubt on the old paradigms and open new prospects for the use of these phytohormones. Particular attention is given to recent advances in the applications of natural cytokinins and their synthetic analogues in biotechnology, agriculture, medicine and cosmetics. The chemical synthesis, properties and the possible use of artificial cytokinins are considered in detail. The review is aimed at researchers interested in the development and applications of new biologically active compounds with a wide spectrum of action on diverse biological objects, from plants to humans.
The bibliography includes 233 references.
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26
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Vylíčilová H, Bryksová M, Matušková V, Doležal K, Plíhalová L, Strnad M. Naturally Occurring and Artificial N9-Cytokinin Conjugates: From Synthesis to Biological Activity and Back. Biomolecules 2020; 10:biom10060832. [PMID: 32485963 PMCID: PMC7356397 DOI: 10.3390/biom10060832] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 05/26/2020] [Accepted: 05/26/2020] [Indexed: 01/18/2023] Open
Abstract
Cytokinins and their sugar or non-sugar conjugates are very active growth-promoting factors in plants, although they occur at very low concentrations. These compounds have been identified in numerous plant species. This review predominantly focuses on 9-substituted adenine-based cytokinin conjugates, both artificial and endogenous, sugar and non-sugar, and their roles in plants. Acquired information about their biological activities, interconversions, and metabolism improves understanding of their mechanisms of action and functions in planta. Although a number of 9-substituted cytokinins occur endogenously, many have also been prepared in laboratories to facilitate the clarification of their physiological roles and the determination of their biological properties. Here, we chart advances in knowledge of 9-substituted cytokinin conjugates from their discovery to current understanding and reciprocal interactions between biological properties and associated structural motifs. Current organic chemistry enables preparation of derivatives with better biological properties, such as improved anti-senescence, strong cell division stimulation, shoot forming, or more persistent stress tolerance compared to endogenous or canonical cytokinins. Many artificial cytokinin conjugates stimulate higher mass production than naturally occurring cytokinins, improve rooting, or simply have high stability or bioavailability. Thus, knowledge of the biosynthesis, metabolism, and activity of 9-substituted cytokinins in various plant species extends the scope for exploiting both natural and artificially prepared cytokinins in plant biotechnology, tissue culture, and agriculture.
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Affiliation(s)
- Hana Vylíčilová
- Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic; (H.V.); (M.B.); (V.M.); (K.D.)
| | - Magdaléna Bryksová
- Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic; (H.V.); (M.B.); (V.M.); (K.D.)
| | - Vlasta Matušková
- Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic; (H.V.); (M.B.); (V.M.); (K.D.)
| | - Karel Doležal
- Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic; (H.V.); (M.B.); (V.M.); (K.D.)
- Laboratory of Growth Regulators, Palacký University & Institute of Experimental Botany ASCR, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic;
| | - Lucie Plíhalová
- Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic; (H.V.); (M.B.); (V.M.); (K.D.)
- Laboratory of Growth Regulators, Palacký University & Institute of Experimental Botany ASCR, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic;
- Correspondence:
| | - Miroslav Strnad
- Laboratory of Growth Regulators, Palacký University & Institute of Experimental Botany ASCR, Šlechtitelů 27, CZ-783 71 Olomouc, Czech Republic;
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Savory EA, Weisberg AJ, Stevens DM, Creason AL, Fuller SL, Pearce EM, Chang JH. Phytopathogenic Rhodococcus Have Diverse Plasmids With Few Conserved Virulence Functions. Front Microbiol 2020; 11:1022. [PMID: 32523572 PMCID: PMC7261884 DOI: 10.3389/fmicb.2020.01022] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 04/27/2020] [Indexed: 11/13/2022] Open
Abstract
Rhodococcus is a genus of Gram-positive bacteria with species that can cause growth deformations to a large number of plant species. This ability to cause disease is hypothesized to be dependent on a cluster of three gene loci on an almost 200 kb-sized linear plasmid. To reevaluate the roles of some of the genes in pathogenicity, we constructed and characterized deletion mutants of fasR and four fas genes. Findings confirmed that fasR, which encodes a putative transcriptional regulator, is necessary for pathogenesis. However, three of the fas genes, implicated in the metabolism of plant growth promoting cytokinins, are dispensable for the ability of the pathogen to cause disease. We also used long-read sequencing technology to generate high quality genome sequences for two phytopathogenic strains in which virulence genes are diverged in sequence and/or hypothesized to have recombined into the chromosome. Surprisingly, findings showed that the two strains carry extremely diverse virulence plasmids. Ortholog clustering identified only 12 genes present on all three virulence plasmids. Rhodococcus requires a small number of horizontally acquired traits to be pathogenic and the transmission of the corresponding genes, via recombination and conjugation, has the potential to rapidly diversify plasmids and bacterial populations.
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Affiliation(s)
- Elizabeth A Savory
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, United States
| | - Alexandra J Weisberg
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, United States
| | - Danielle M Stevens
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, United States
| | - Allison L Creason
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, United States
| | - Skylar L Fuller
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, United States
| | - Emma M Pearce
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, United States
| | - Jeff H Chang
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, United States.,Center for Genome Research and Biocomputing, Oregon State University, Corvallis, OR, United States
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28
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Harris MO, Pitzschke A. Plants make galls to accommodate foreigners: some are friends, most are foes. THE NEW PHYTOLOGIST 2020; 225:1852-1872. [PMID: 31774564 DOI: 10.1111/nph.16340] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Accepted: 07/24/2019] [Indexed: 06/10/2023]
Abstract
At the colonization site of a foreign entity, plant cells alter their trajectory of growth and development. The resulting structure - a plant gall - accommodates various needs of the foreigner, which are phylogenetically diverse: viruses, bacteria, protozoa, oomycetes, true fungi, parasitic plants, and many types of animals, including rotifers, nematodes, insects, and mites. The plant species that make galls also are diverse. We assume gall production costs the plant. All is well if the foreigner provides a gift that makes up for the cost. Nitrogen-fixing nodule-inducing bacteria provide nutritional services. Gall wasps pollinate fig trees. Unfortunately for plants, most galls are made for foes, some of which are deeply studied pathogens and pests: Agrobacterium tumefaciens, Rhodococcus fascians, Xanthomonas citri, Pseudomonas savastanoi, Pantoea agglomerans, 'Candidatus' phytoplasma, rust fungi, Ustilago smuts, root knot and cyst nematodes, and gall midges. Galls are an understudied phenomenon in plant developmental biology. We propose gall inception for discovering unifying features of the galls that plants make for friends and foes, talk about molecules that plants and gall-inducers use to get what they want from each other, raise the question of whether plants colonized by arbuscular mycorrhizal fungi respond in a gall-like manner, and present a research agenda.
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Affiliation(s)
- Marion O Harris
- Department of Entomology, North Dakota State University, Fargo, ND, 58014, USA
| | - Andrea Pitzschke
- Department of Biosciences, Salzburg University, Hellbrunner Strasse 34, A-5020, Salzburg, Austria
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29
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Wang X, Lin S, Liu D, Gan L, McAvoy R, Ding J, Li Y. Evolution and roles of cytokinin genes in angiosperms 1: Do ancient IPTs play housekeeping while non-ancient IPTs play regulatory roles? HORTICULTURE RESEARCH 2020; 7:28. [PMID: 32140237 PMCID: PMC7049300 DOI: 10.1038/s41438-019-0211-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2019] [Revised: 06/04/2019] [Accepted: 06/05/2019] [Indexed: 05/07/2023]
Abstract
Isopentenyltransferase (IPT) genes, including those encoding ATP/ADP-IPTs and tRNA-IPTs, control the rate-limiting steps of the biosynthesis of N 6-(Δ2-isopentenyl)adenine (iP)-type and trans-zeatin (tZ)-type cytokinins and cis-zeatin (cZ)-type cytokinins, respectively. However, the evolution and roles of these IPTs in angiosperms are not well understood. Here, we report comprehensive analyses of the origins, evolution, expression patterns, and possible roles of ATP/ADP-IPTs and tRNA-IPTs in angiosperms. We found that Class I and II tRNA-IPTs likely coexisted in the last common ancestor of eukaryotes, while ATP/ADP-IPTs likely originated from a Class II tRNA-IPT before the divergence of angiosperms. tRNA-IPTs are conservatively retained as 2-3 copies, but ATP/ADP-IPTs exhibit considerable expansion and diversification. Additionally, tRNA-IPTs are constitutively expressed throughout the plant, whereas the expression of ATP/ADP-IPTs is tissue-specific and rapidly downregulated by abiotic stresses. Furthermore, previous studies and our present study indicate that ATP/ADP-IPTs and their products, iPs/tZs, may regulate responses to environmental stresses and organ development in angiosperms. We therefore hypothesize that tRNA-IPTs and the associated cZs play a housekeeping role, whereas ATP/ADP-IPTs and the associated iP/tZ-type cytokinins play regulatory roles in organ development and stress responses in angiosperms, which echoes the conclusions and hypothesis presented in the accompanying study by Wang, X. et al Evolution and roles of cytokinin genes in angiosperms 2: Do ancient CKXs play housekeeping roles while non-ancient CKXs play regulatory roles? Hortic Res 10.1038/s41438-020-0246-z.
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Affiliation(s)
- Xiaojing Wang
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and the College of Horticulture, Nanjing Agricultural University, Nanjing, P. R. China
| | - Shanshan Lin
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and the College of Horticulture, Nanjing Agricultural University, Nanjing, P. R. China
| | - Decai Liu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and the College of Horticulture, Nanjing Agricultural University, Nanjing, P. R. China
| | - Lijun Gan
- College of Life Sciences, Nanjing Agricultural University, Nanjing, P. R. China
| | - Richard McAvoy
- Department of Plant Science and Landscape Architecture, University of Connecticut, Storrs, CT 06269 USA
| | - Jing Ding
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and the College of Horticulture, Nanjing Agricultural University, Nanjing, P. R. China
| | - Yi Li
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and the College of Horticulture, Nanjing Agricultural University, Nanjing, P. R. China
- Department of Plant Science and Landscape Architecture, University of Connecticut, Storrs, CT 06269 USA
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30
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Vereecke D, Zhang Y, Francis IM, Lambert PQ, Venneman J, Stamler RA, Kilcrease J, Randall JJ. Functional Genomics Insights Into the Pathogenicity, Habitat Fitness, and Mechanisms Modifying Plant Development of Rhodococcus sp. PBTS1 and PBTS2. Front Microbiol 2020; 11:14. [PMID: 32082278 PMCID: PMC7002392 DOI: 10.3389/fmicb.2020.00014] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Accepted: 01/06/2020] [Indexed: 01/05/2023] Open
Abstract
Pistachio Bushy Top Syndrome (PBTS) is a recently emerged disease that has strongly impacted the pistachio industry in California, Arizona, and New Mexico. The disease is caused by two bacteria, designated PBTS1 that is related to Rhodococcus corynebacterioides and PBTS2 that belongs to the species R. fascians. Here, we assessed the pathogenic character of the causative agents and examined their chromosomal sequences to predict the presence of particular functions that might contribute to the observed co-occurrence and their effect on plant hosts. In diverse assays, we confirmed the pathogenicity of the strains on "UCB-1" pistachio rootstock and showed that they can also impact the development of tobacco species, but concurrently inconsistencies in the ability to induce symptoms were revealed. We additionally evidence that fas genes are present only in a subpopulation of pure PBTS1 and PBTS2 cultures after growth on synthetic media, that these genes are easily lost upon cultivation in rich media, and that they are enriched for in an in planta environment. Analysis of the chromosomal sequences indicated that PBTS1 and PBTS2 might have complementary activities that would support niche partitioning. Growth experiments showed that the nutrient utilization pattern of both PBTS bacteria was not identical, thus avoiding co-inhabitant competition. PBTS2 appeared to have the potential to positively affect the habitat fitness of PBTS1 by improving its resistance against increased concentrations of copper and penicillins. Finally, mining the chromosomes of PBTS1 and PBTS2 suggested that the bacteria could produce cytokinins, auxins, and plant growth-stimulating volatiles and that PBTS2 might interfere with ethylene levels, in support of their impact on plant development. Subsequent experimentation supported these in silico predictions. Altogether, our data provide an explanation for the observed pathogenic behavior and unveil part of the strategies used by PBTS1 and PBTS2 to interact with plants.
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Affiliation(s)
- Danny Vereecke
- Entomology, Plant Pathology, and Weed Science, New Mexico State University, Las Cruces, NM, United States
| | - Yucheng Zhang
- Department of Plant Pathology, University of Florida, Gainesville, FL, United States
| | - Isolde M Francis
- Department of Biology, California State University, Bakersfield, CA, United States
| | - Paul Q Lambert
- Entomology, Plant Pathology, and Weed Science, New Mexico State University, Las Cruces, NM, United States
| | - Jolien Venneman
- Department of Plants and Crops, Ghent University, Ghent, Belgium
| | - Rio A Stamler
- Entomology, Plant Pathology, and Weed Science, New Mexico State University, Las Cruces, NM, United States
| | - James Kilcrease
- Entomology, Plant Pathology, and Weed Science, New Mexico State University, Las Cruces, NM, United States
| | - Jennifer J Randall
- Entomology, Plant Pathology, and Weed Science, New Mexico State University, Las Cruces, NM, United States
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31
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Cerbantez-Bueno VE, Zúñiga-Mayo VM, Reyes-Olalde JI, Lozano-Sotomayor P, Herrera-Ubaldo H, Marsch-Martinez N, de Folter S. Redundant and Non-redundant Functions of the AHK Cytokinin Receptors During Gynoecium Development. FRONTIERS IN PLANT SCIENCE 2020; 11:568277. [PMID: 33117412 PMCID: PMC7575793 DOI: 10.3389/fpls.2020.568277] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 09/17/2020] [Indexed: 05/17/2023]
Abstract
The phytohormone cytokinin is crucial for plant growth and development. The site of action of cytokinin in the plant is dependent on the expression of the cytokinin receptors. In Arabidopsis, there are three cytokinin receptors that present some overlap in expression pattern. Functional studies demonstrated that the receptors play highly redundant roles but also have specialized functions. Here, we focus on gynoecium development, which is the female reproductive part of the plant. Cytokinin signaling has been demonstrated to be important for reproductive development, positively affecting seed yield and fruit production. Most of these developmental processes are regulated by cytokinin during early gynoecium development. While some information is available, there is a gap in knowledge on cytokinin function and especially on the cytokinin receptors during early gynoecium development. Therefore, we studied the expression patterns and the role of the cytokinin receptors during gynoecium development. We found that the three receptors are expressed in the gynoecium and that they have redundant and specialized functions.
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Affiliation(s)
- Vincent E. Cerbantez-Bueno
- Unidad de Genómica Avanzada (UGA-LANGEBIO), Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Irapuato, Mexico
| | - Victor M. Zúñiga-Mayo
- Unidad de Genómica Avanzada (UGA-LANGEBIO), Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Irapuato, Mexico
| | - J. Irepan Reyes-Olalde
- Unidad de Genómica Avanzada (UGA-LANGEBIO), Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Irapuato, Mexico
| | - Paulina Lozano-Sotomayor
- Unidad de Genómica Avanzada (UGA-LANGEBIO), Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Irapuato, Mexico
| | - Humberto Herrera-Ubaldo
- Unidad de Genómica Avanzada (UGA-LANGEBIO), Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Irapuato, Mexico
| | | | - Stefan de Folter
- Unidad de Genómica Avanzada (UGA-LANGEBIO), Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Irapuato, Mexico
- *Correspondence: Stefan de Folter,
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32
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Abstract
Plants are under relentless challenge by pathogenic bacteria, fungi, and oomycetes, for whom they provide a resource of living space and nutrients. Upon detection of pathogens, plants carry out multiple layers of defense response, orchestrated by a tightly organized network of hormones. In this review, we provide an overview of the phytohormones involved in immunity and the ways pathogens manipulate their biosynthesis and signaling pathways. We highlight recent developments, including the discovery of a defense signaling molecule, new insights into hormone biosynthesis, and the increasing importance of signaling hubs at which hormone pathways intersect.
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Affiliation(s)
- Marco Bürger
- Plant Biology Laboratory, Salk Institute for Biological Studies, La Jolla, CA 92037, USA.
| | - Joanne Chory
- Howard Hughes Medical Institute, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
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33
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Virulent Rhodococcus fascians Produce Unique Methylated Cytokinins. PLANTS 2019; 8:plants8120582. [PMID: 31817945 PMCID: PMC6963480 DOI: 10.3390/plants8120582] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 12/05/2019] [Accepted: 12/05/2019] [Indexed: 12/15/2022]
Abstract
Some strains of Rhodococcus fascians exist only as epiphytes on the plant surface whereas others can become endophytic and cause various abnormalities including the release of multiple buds and reduced root growth. The abnormalities reflect the action of cytokinin. The strains that can become endophytic harbour a linear plasmid that carries cytokinin biosynthesis, activation and destruction genes. However, both epiphytic and endophytic forms can release cytokinin into culture, affect cytokinin metabolism within inoculated plants and enhance the expression of sugar and amino acid transporters and cell wall invertases, but only the endophytic form markedly affects the morphology of the plant. A unique methylated cytokinin, dimethylated N6-(∆2-isopentenyl)adenine (2-MeiP), operating in a high sugar environment, is the likely causative factor of the severe morphological abnormalities observed when plants are inoculated with R. fascians strains carrying the linear plasmid.
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Abstract
Plant age is a crucial factor in determining the outcome of a host-pathogen interaction. In successive developmental stages throughout their life cycles, plants face dynamic changes in biotic and abiotic conditions that create distinct ecological niches for host-pathogen interactions. As an adaptive strategy, plants have evolved intrinsic regulatory networks that integrate developmental signals with those from pathogen perception and defense activation. As a result, amplitude and timing of defense responses are optimized, so as to balance the cost and benefit of immunity activation. A general term "age-related resistance" refers to a gain of disease resistance against a certain pathogen when plants reach a relatively mature stage. Age-related resistance is a common observation on fruits, vegetables, and row crops for their resistance against viruses, bacteria, fungi, oomycetes pathogens, and insects. This review focuses on the recent advances in understanding the molecular mechanisms of how plants coordinate developmental timing and immune response.
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Affiliation(s)
- Lanxi Hu
- Department of Plant Pathology, University of Georgia, Athens, GA 30602
| | - Li Yang
- Department of Plant Pathology, University of Georgia, Athens, GA 30602
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35
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Thapa SP, Davis EW, Lyu Q, Weisberg AJ, Stevens DM, Clarke CR, Coaker G, Chang JH. The Evolution, Ecology, and Mechanisms of Infection by Gram-Positive, Plant-Associated Bacteria. ANNUAL REVIEW OF PHYTOPATHOLOGY 2019; 57:341-365. [PMID: 31283433 DOI: 10.1146/annurev-phyto-082718-100124] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Gram-positive bacteria are prominent members of plant-associated microbial communities. Although many are hypothesized to be beneficial, some are causative agents of economically important diseases of crop plants. Because the features of Gram-positive bacteria are fundamentally different relative to those of Gram-negative bacteria, the evolution and ecology as well as the mechanisms used to colonize and infect plants also differ. Here, we discuss recent advances in our understanding of Gram-positive, plant-associated bacteria and provide a framework for future research directions on these important plant symbionts.
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Affiliation(s)
- Shree P Thapa
- Department of Plant Pathology, University of California, Davis, California 95616, USA
| | - Edward W Davis
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon 97331, USA;
- Molecular and Cellular Biology Program, Oregon State University, Corvallis, Oregon 97331, USA
- Center for Genome Research and Biocomputing, Oregon State University, Corvallis, Oregon 97331, USA
| | - Qingyang Lyu
- Department of Plant Pathology, University of California, Davis, California 95616, USA
| | - Alexandra J Weisberg
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon 97331, USA;
| | - Danielle M Stevens
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon 97331, USA;
- Integrative Genetics and Genomics, University of California, Davis, California 95616, USA
| | - Christopher R Clarke
- Genetic Improvement for Fruits and Vegetables Laboratory, Agricultural Research Service, US Department of Agriculture, Beltsville, Maryland 20705, USA
| | - Gitta Coaker
- Department of Plant Pathology, University of California, Davis, California 95616, USA
| | - Jeff H Chang
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon 97331, USA;
- Molecular and Cellular Biology Program, Oregon State University, Corvallis, Oregon 97331, USA
- Center for Genome Research and Biocomputing, Oregon State University, Corvallis, Oregon 97331, USA
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Stringlis IA, Zhang H, Pieterse CMJ, Bolton MD, de Jonge R. Microbial small molecules - weapons of plant subversion. Nat Prod Rep 2019; 35:410-433. [PMID: 29756135 DOI: 10.1039/c7np00062f] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Covering: up to 2018 Plants live in close association with a myriad of microbes that are generally harmless. However, the minority of microbes that are pathogens can severely impact crop quality and yield, thereby endangering food security. By contrast, beneficial microbes provide plants with important services, such as enhanced nutrient uptake and protection against pests and diseases. Like pathogens, beneficial microbes can modulate host immunity to efficiently colonize the nutrient-rich niches within and around the roots and aerial tissues of a plant, a phenomenon mirroring the establishment of commensal microbes in the human gut. Numerous ingenious mechanisms have been described by which pathogenic and beneficial microbes in the plant microbiome communicate with their host, including the delivery of immune-suppressive effector proteins and the production of phytohormones, toxins and other bioactive molecules. Plants signal to their associated microbes via exudation of photosynthetically fixed carbon sources, quorum-sensing mimicry molecules and selective secondary metabolites such as strigolactones and flavonoids. Molecular communication thus forms an integral part of the establishment of both beneficial and pathogenic plant-microbe relations. Here, we review the current knowledge on microbe-derived small molecules that can act as signalling compounds to stimulate plant growth and health by beneficial microbes on the one hand, but also as weapons for plant invasion by pathogens on the other. As an exemplary case, we used comparative genomics to assess the small molecule biosynthetic capabilities of the Pseudomonas genus; a genus rich in both plant pathogenic and beneficial microbes. We highlight the biosynthetic potential of individual microbial genomes and the population at large, providing evidence for the hypothesis that the distinction between detrimental and beneficial microbes is increasingly fading. Knowledge on the biosynthesis and molecular activity of microbial small molecules will aid in the development of successful biological agents boosting crop resiliency in a sustainable manner and could also provide scientific routes to pathogen inhibition or eradication.
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Affiliation(s)
- Ioannis A Stringlis
- Plant-Microbe Interactions, Department of Biology, Science4Life, Utrecht University, Utrecht, The Netherlands.
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Nouioui I, Cortés-albayay C, Carro L, Castro JF, Gtari M, Ghodhbane-Gtari F, Klenk HP, Tisa LS, Sangal V, Goodfellow M. Genomic Insights Into Plant-Growth-Promoting Potentialities of the Genus Frankia. Front Microbiol 2019; 10:1457. [PMID: 31333602 PMCID: PMC6624747 DOI: 10.3389/fmicb.2019.01457] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 06/11/2019] [Indexed: 12/19/2022] Open
Abstract
This study was designed to determine the plant growth promoting (PGP) potential of members of the genus Frankia. To this end, the genomes of 21 representative strains were examined for genes associated directly or indirectly with plant growth. All of the Frankia genomes contained genes that encoded for products associated with the biosynthesis of auxins [indole-3-glycerol phosphate synthases, anthranilate phosphoribosyltransferases (trpD), anthranilate synthases, and aminases (trpA and B)], cytokinins (11 well-conserved genes within the predicted biosynthetic gene cluster), siderophores, and nitrogenases (nif operon except for atypical Frankia) as well as genes that modulate the effects of biotic and abiotic environmental stress (e.g., alkyl hydroperoxide reductases, aquaporin Z, heat shock proteins). In contrast, other genes were associated with strains assigned to one or more of four host-specific clusters. The genes encoding for phosphate solubilization (e.g., low-affinity inorganic phosphate transporters) and lytic enzymes (e.g., cellulases) were found in Frankia cluster 1 genomes, while other genes were found only in cluster 3 genomes (e.g., alkaline phosphatases, extracellular endoglucanases, pectate lyases) or cluster 4 and subcluster 1c genomes (e.g., NAD(P) transhydrogenase genes). Genes encoding for chitinases were found only in the genomes of the type strains of Frankia casuarinae, F. inefficax, F. irregularis, and F. saprophytica. In short, these in silico genome analyses provide an insight into the PGP abilities of Frankia strains of known taxonomic provenance. This is the first study designed to establish the underlying genetic basis of cytokinin production in Frankia strains. Also, the discovery of additional genes in the biosynthetic gene cluster involved in cytokinin production opens up the prospect that Frankia may have novel molecular mechanisms for cytokinin biosynthesis.
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Affiliation(s)
- Imen Nouioui
- School of Natural and Environmental Sciences, Faculty of Science, Agriculture and Engineering, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Carlos Cortés-albayay
- School of Natural and Environmental Sciences, Faculty of Science, Agriculture and Engineering, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Lorena Carro
- Microbiology and Genetics Department, Universidad de Salamanca, Salamanca, Spain
| | - Jean Franco Castro
- The Chilean Collection of Microbial Genetic Resources (CChRGM), Instituto de Investigaciones Agropecuarias (INIA) – Quilamapu, Chillán, Chile
| | - Maher Gtari
- Institut National des Sciences Appliquées et de Technologie, Université de Carthage Centre Urbain Nord, Tunis, Tunisia
| | - Faten Ghodhbane-Gtari
- Institut National des Sciences Appliquées et de Technologie, Université de Carthage Centre Urbain Nord, Tunis, Tunisia
- Laboratoire Microorganismes et Biomolécules Actives, Faculté de Sciences de Tunis, Université de Tunis El Manar, Tunis, Tunisia
| | - Hans-Peter Klenk
- School of Natural and Environmental Sciences, Faculty of Science, Agriculture and Engineering, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Louis S. Tisa
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, NH, United States
| | - Vartul Sangal
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, United Kingdom
| | - Michael Goodfellow
- School of Natural and Environmental Sciences, Faculty of Science, Agriculture and Engineering, Newcastle University, Newcastle upon Tyne, United Kingdom
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Li Y, Liu J, Díaz-Cruz G, Cheng Z, Bignell DRD. Virulence mechanisms of plant-pathogenic Streptomyces species: an updated review. MICROBIOLOGY-SGM 2019; 165:1025-1040. [PMID: 31162023 DOI: 10.1099/mic.0.000818] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Gram-positive Actinobacteria from the genus Streptomyces are best known for their morphological complexity and for their ability to produce numerous bioactive specialized metabolites with useful applications in human and veterinary medicine and in agriculture. In contrast, the ability to infect living plant tissues and to cause diseases of root and tuber crops such as potato common scab (CS) is a rare attribute among members of this genus. Research on the virulence mechanisms of plant-pathogenic Streptomyces spp. has revealed the importance of the thaxtomin phytotoxins as key pathogenicity determinants produced by several species. In addition, other phytotoxic specialized metabolites may contribute to the development or severity of disease caused by Streptomyces spp., along with the production of phytohormones and secreted proteins. A thorough understanding of the molecular mechanisms of plant pathogenicity will enable the development of better management procedures for controlling CS and other plant diseases caused by the Streptomyces.
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Affiliation(s)
- Yuting Li
- Department of Biology, Memorial University of Newfoundland, St John's, NL A1B 3X9, Canada
| | - Jingyu Liu
- Department of Biology, Memorial University of Newfoundland, St John's, NL A1B 3X9, Canada
| | - Gustavo Díaz-Cruz
- Department of Biology, Memorial University of Newfoundland, St John's, NL A1B 3X9, Canada
| | - Zhenlong Cheng
- Department of Biology, Memorial University of Newfoundland, St John's, NL A1B 3X9, Canada
| | - Dawn R D Bignell
- Department of Biology, Memorial University of Newfoundland, St John's, NL A1B 3X9, Canada
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Lastochkina O, Seifikalhor M, Aliniaeifard S, Baymiev A, Pusenkova L, Garipova S, Kulabuhova D, Maksimov I. Bacillus Spp.: Efficient Biotic Strategy to Control Postharvest Diseases of Fruits and Vegetables. PLANTS 2019; 8:plants8040097. [PMID: 31013814 PMCID: PMC6524353 DOI: 10.3390/plants8040097] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Revised: 03/30/2019] [Accepted: 04/03/2019] [Indexed: 12/13/2022]
Abstract
: Postharvest diseases significantly reduce the shelf-life of harvested fruits/vegetables worldwide. Bacillus spp. are considered to be an eco-friendly and bio-safe alternative to traditional chemical fungicides/bactericides due to their intrinsic ability to induce native anti-stress pathways in plants. This review compiles information from multiple scientific databases (Scopus, ScienceDirect, GoogleScholar, ResearchGate, etc.) using the keywords "postharvest diseases", "Bacillus", "Bacillus subtilis", "biocontrol", "storage", "losses", and "fruits/vegetables". To date, numerous examples of successful Bacillus spp. application in controlling various postharvest-emerged pathogens of different fruits/vegetables during handling, transportation, and storage have been described in the literature. The mechanism/s of such action is/are still largely unknown; however, it is suggested that they include: i) competition for space/nutrients with pathogens; ii) production of various bio-active substances with antibiotic activity and cell wall-degrading compounds; and iii) induction of systemic resistance. With that, Bacillus efficiency may depend on various factors including strain characteristics (epiphytes or endophytes), application methods (before or after harvest/storage), type of pathogens/hosts, etc. Endophytic B. subtilis-based products can be more effective because they colonize internal plant tissues and are less dependent on external environmental factors while protecting cells inside. Nevertheless, the mechanism/s of Bacillus action on harvested fruits/vegetables is largely unknown and requires further detailed investigations to fully realize their potential in agricultural/food industries.
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Affiliation(s)
- Oksana Lastochkina
- Bashkir Research Institute of Agriculture, Ufa Federal Research Centre of the Russian Academy of Sciences, 450059 Ufa, Russia.
- Institute of Biochemistry and Genetics, Ufa Federal Research Centre of the Russian Academy of Sciences, 450054 Ufa, Russia.
| | - Maryam Seifikalhor
- Department of Plant Biology, Center of Excellence in Phylogeny of Living Organisms in Iran, School of Biology, College of Science, University of Tehran, Tehran 14155, Iran.
| | - Sasan Aliniaeifard
- Department of Horticulture, College of Aburaihan, University of Tehran, Pakdasht, Tehran 3391653775, Iran.
| | - Andrey Baymiev
- Institute of Biochemistry and Genetics, Ufa Federal Research Centre of the Russian Academy of Sciences, 450054 Ufa, Russia.
- Department of Biology, Bashkir State University, 450076 Ufa, Russia.
| | - Ludmila Pusenkova
- Bashkir Research Institute of Agriculture, Ufa Federal Research Centre of the Russian Academy of Sciences, 450059 Ufa, Russia.
| | - Svetlana Garipova
- Bashkir Research Institute of Agriculture, Ufa Federal Research Centre of the Russian Academy of Sciences, 450059 Ufa, Russia.
- Department of Biology, Bashkir State University, 450076 Ufa, Russia.
| | - Darya Kulabuhova
- Bashkir Research Institute of Agriculture, Ufa Federal Research Centre of the Russian Academy of Sciences, 450059 Ufa, Russia.
| | - Igor Maksimov
- Institute of Biochemistry and Genetics, Ufa Federal Research Centre of the Russian Academy of Sciences, 450054 Ufa, Russia.
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Cortleven A, Leuendorf JE, Frank M, Pezzetta D, Bolt S, Schmülling T. Cytokinin action in response to abiotic and biotic stresses in plants. PLANT, CELL & ENVIRONMENT 2019; 42:998-1018. [PMID: 30488464 DOI: 10.1111/pce.13494] [Citation(s) in RCA: 187] [Impact Index Per Article: 37.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 11/12/2018] [Accepted: 11/20/2018] [Indexed: 05/20/2023]
Abstract
The phytohormone cytokinin was originally discovered as a regulator of cell division. Later, it was described to be involved in regulating numerous processes in plant growth and development including meristem activity, tissue patterning, and organ size. More recently, diverse functions for cytokinin in the response to abiotic and biotic stresses have been reported. Cytokinin is required for the defence against high light stress and to protect plants from a novel type of abiotic stress caused by an altered photoperiod. Additionally, cytokinin has a role in the response to temperature, drought, osmotic, salt, and nutrient stress. Similarly, the full response to certain plant pathogens and herbivores requires a functional cytokinin signalling pathway. Conversely, different types of stress impact cytokinin homeostasis. The diverse functions of cytokinin in responses to stress and crosstalk with other hormones are described. Its emerging roles as a priming agent and as a regulator of growth-defence trade-offs are discussed.
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Affiliation(s)
- Anne Cortleven
- Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, D-14195, Berlin, Germany
| | - Jan Erik Leuendorf
- Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, D-14195, Berlin, Germany
| | - Manuel Frank
- Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, D-14195, Berlin, Germany
| | - Daniela Pezzetta
- Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, D-14195, Berlin, Germany
| | - Sylvia Bolt
- Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, D-14195, Berlin, Germany
| | - Thomas Schmülling
- Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, D-14195, Berlin, Germany
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41
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Daudu D, Kisiala A, Werner Ribeiro C, Mélin C, Perrot L, Clastre M, Courdavault V, Papon N, Oudin A, Courtois M, Dugé de Bernonville T, Gaucher M, Degrave A, Lanoue A, Lanotte P, Schouler C, Brisset MN, Emery RN, Pichon O, Carpin S, Giglioli-Guivarc’h N, Crèche J, Besseau S, Glévarec G. Setting-up a fast and reliable cytokinin biosensor based on a plant histidine kinase receptor expressed in Saccharomyces cerevisiae. J Biotechnol 2019; 289:103-111. [DOI: 10.1016/j.jbiotec.2018.11.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 11/14/2018] [Accepted: 11/16/2018] [Indexed: 12/21/2022]
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42
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Francis IM, Vereecke D. Plant-Associated Rhodococcus Species, for Better and for Worse. BIOLOGY OF RHODOCOCCUS 2019. [DOI: 10.1007/978-3-030-11461-9_13] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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43
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Jameson PE, Dhandapani P, Song J, Zatloukal M, Strnad M, Remus-Emsermann MNP, Schlechter RO, Novák O. The Cytokinin Complex Associated With Rhodococcus fascians: Which Compounds Are Critical for Virulence? FRONTIERS IN PLANT SCIENCE 2019; 10:674. [PMID: 31191583 PMCID: PMC6539147 DOI: 10.3389/fpls.2019.00674] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 05/03/2019] [Indexed: 05/22/2023]
Abstract
Virulent strains of Rhodococcus fascians cause a range of disease symptoms, many of which can be mimicked by application of cytokinin. Both virulent and avirulent strains produce a complex of cytokinins, most of which can be derived from tRNA degradation. To test the three current hypotheses regarding the involvement of cytokinins as virulence determinants, we used PCR to detect specific genes, previously associated with a linear virulence plasmid, including two methyl transferase genes (mt1 and mt2) and fas4 (dimethyl transferase), of multiple strains of R. fascians. We inoculated Pisum sativum (pea) seeds with virulent and avirulent strains of R. fascians, monitored the plants over time and compared these to mock-inoculated controls. We used RT-qPCR to monitor the expression of mt1, mt2, and fas4 in inoculated tissues and LC-MS/MS to obtain a comprehensive picture of the cytokinin complement of inoculated cotyledons, roots and shoots over time. The presence and expression of mt1 and mt2 was associated with those strains of R. fascians classed as virulent, and not those classed as avirulent. Expression of mt1, mt2, and fas4 peaked at 9 days post-inoculation (dpi) in cotyledons and at 15 dpi in shoots and roots developed from seeds inoculated with virulent strain 602. Pea plants inoculated with virulent and avirulent strains of R. fascians both contained cytokinins likely to have been derived from tRNA turnover including the 2-methylthio cytokinins and cis-zeatin-derivatives. Along with the isopentenyladenine-type cytokinins, the levels of these compounds did not correlate with virulence. Only the novel 1- and 2-methylated isopentenyladenine cytokinins were uniquely associated with infection by the virulent strains and are, therefore, the likely causative factors of the disease symptoms.
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Affiliation(s)
- Paula E. Jameson
- School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
- *Correspondence: Paula E. Jameson
| | - Pragathi Dhandapani
- School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
| | - Jiancheng Song
- School of Life Sciences, Yantai University, Yantai, China
| | - Marek Zatloukal
- Laboratory of Growth Regulators, The Czech Academy of Sciences, Faculty of Science, Institute of Experimental Botany & Palacký University, Olomouc, Czech Republic, China
| | - Miroslav Strnad
- Laboratory of Growth Regulators, The Czech Academy of Sciences, Faculty of Science, Institute of Experimental Botany & Palacký University, Olomouc, Czech Republic, China
| | | | - Rudolf O. Schlechter
- School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
| | - Ondrej Novák
- Laboratory of Growth Regulators, The Czech Academy of Sciences, Faculty of Science, Institute of Experimental Botany & Palacký University, Olomouc, Czech Republic, China
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44
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Ullah C, Unsicker SB, Reichelt M, Gershenzon J, Hammerbacher A. Accumulation of Catechin and Proanthocyanidins in Black Poplar Stems After Infection by Plectosphaerella populi: Hormonal Regulation, Biosynthesis and Antifungal Activity. FRONTIERS IN PLANT SCIENCE 2019; 10:1441. [PMID: 31803202 PMCID: PMC6873352 DOI: 10.3389/fpls.2019.01441] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 10/16/2019] [Indexed: 05/08/2023]
Abstract
Flavan-3-ols including the monomeric catechin and the polymeric proanthocyanidins (PAs) are abundant phenolic metabolites in poplar (Populus spp.) previously described to protect leaves against pathogen infection. However, it is not known whether stems are also defended in this way. Here we investigated flavan-3-ol accumulation, activity, and the regulation of formation in black poplar (P. nigra) stems after infection by a newly described fungal stem pathogen, Plectosphaerella populi, which forms canker-like lesions in stems. We showed that flavan-3-ol contents increased in P. populi-infected black poplar stems over the course of infection compared to non-infected controls. Transcripts of leucoanthocyanidin reductase (LAR) and anthocyanidin reductase (ANR) genes involved in the last steps of flavan-3-ol biosynthesis were also upregulated upon fungal infection indicating de novo biosynthesis. Amending culture medium with catechin and PAs reduced the mycelial growth of P. populi, suggesting that these metabolites act as anti-pathogen defenses in poplar in vivo. Among the hormones, salicylic acid (SA) was higher in P. populi-infected tissues compared to the non-infected controls over the course of infection studied, while jasmonic acid (JA) and JA-isoleucine (JA-Ile) levels were higher than controls only at the early stages of infection. Interestingly, cytokinins (CKs) were also upregulated in P. populi-infected stems. Poplar saplings treated with CK showed decreased levels of flavan-3-ols and SA in stems suggesting a negative association between CK and flavan-3-ol accumulation. Taken together, the sustained upregulation of SA in correlation with catechin and PA accumulation suggests that this is the dominant hormone inducing the formation of antifungal flavan-3-ols during P. populi infection of poplar stems.
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Affiliation(s)
- Chhana Ullah
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena, Germany
- *Correspondence: Chhana Ullah,
| | - Sybille B. Unsicker
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Michael Reichelt
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Jonathan Gershenzon
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Almuth Hammerbacher
- Department of Zoology and Entomology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria, South Africa
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45
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Spallek T, Gan P, Kadota Y, Shirasu K. Same tune, different song-cytokinins as virulence factors in plant-pathogen interactions? CURRENT OPINION IN PLANT BIOLOGY 2018; 44:82-87. [PMID: 29555490 DOI: 10.1016/j.pbi.2018.03.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 03/02/2018] [Accepted: 03/07/2018] [Indexed: 05/22/2023]
Abstract
Virulence factors are molecules that enable plant pathogens to infect and colonize host tissues successfully. These molecules co-evolve with host genes to ensure functionality and to avoid recognition by the host immune system. Some pathogens also produce the plant growth hormone cytokinin (CK) and other plant hormones that contribute to virulence without being subjected to the molecular arms race. Here, we summarize recent findings regarding the role of CKs during infection and the establishment of plant diseases. We discuss commonalities and differences in CK biosynthesis, perception, and activity in infections by different phytopathogenic bacteria, fungi, nematodes and parasitic plants. Finally, we attempt to answer the question if CKs can be classified as bona fide virulence factors.
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Affiliation(s)
- Thomas Spallek
- RIKEN Center for Sustainable Resource Science, Yokohama 230-0045, Japan.
| | - Pamela Gan
- RIKEN Center for Sustainable Resource Science, Yokohama 230-0045, Japan
| | - Yasuhiro Kadota
- RIKEN Center for Sustainable Resource Science, Yokohama 230-0045, Japan
| | - Ken Shirasu
- RIKEN Center for Sustainable Resource Science, Yokohama 230-0045, Japan; Graduate School of Science, The University of Tokyo, Bunkyo, Tokyo 113-0033, Japan.
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46
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Manipulation of cytokinin level in the ergot fungus Claviceps purpurea emphasizes its contribution to virulence. Curr Genet 2018; 64:1303-1319. [PMID: 29850931 DOI: 10.1007/s00294-018-0847-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 05/15/2018] [Accepted: 05/28/2018] [Indexed: 11/30/2022]
Abstract
Pathogen-derived cytokinins (CKs) have been recognized as important virulence factor in several host-pathogen interactions and it was demonstrated multiple times that phytopathogenic fungi form CKs via the tRNA degradation pathway. In contrast to previous studies, the focus of this study is on the second step of CK formation and CK degradation to improve our understanding of the biosynthesis in fungi on the one hand, and to understand CK contribution to the infection process of Claviceps purpurea on the other hand. The ergot fungus Claviceps purpurea is a biotrophic phytopathogen with a broad host range including economically important crops causing harvest intoxication upon infection. Its infection process is restricted to unfertilized ovaries without causing macroscopic defense symptoms. Thus, sophisticated host manipulation strategies are implicated. The cytokinin (CK) plant hormones are known to regulate diverse plant cell processes, and several plant pathogens alter CK levels during infection. C. purpurea synthesizes CKs via two mechanisms, and fungus-derived CKs influence the host-pathogen interaction but not fungus itself. CK deficiency in fungi with impact on virulence has only been achieved to date by deletion of a tRNA-ipt gene that is also involved in a process of translation regulation. To obtain a better understanding of CK biosynthesis and CKs' contribution to the plant-fungus interaction, we applied multiple approaches to generate strains with altered or depleted CK content. The first approach is based on deletion of the two CK phosphoribohydrolase (LOG)-encoding genes, which are believed to be essential for the release of active CKs. Single and double deletion strains were able to produce all types of CKs. Apparently, log gene products are dispensable for the formation of CKs and so alternative activation pathways must be present. The CK biosynthesis pathway remains unaffected in the second approach, because it is based on heterologous overexpression of CK-degrading enzymes from maize (ZmCKX1). Zmckx1 overexpressing C. purpurea strains shows strong CKX activity and drastically reduced CK levels. The strains are impaired in virulence, which reinforces the assumption that fungal-derived CKs are crucial for full virulence. Taken together, this study comprises the first analysis of a log depletion mutant that proved the presence of alternative cytokinin activation pathways in fungi and showed that heterologous CKX expression is a suitable approach for CK level reduction.
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47
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Vereecke D. Comment on "Evolutionary transitions between beneficial and phytopathogenic Rhodococcus challenge disease management". eLife 2018; 7:35238. [PMID: 29737966 PMCID: PMC5951678 DOI: 10.7554/elife.35238] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Accepted: 04/13/2018] [Indexed: 02/06/2023] Open
Abstract
I would like to report significant issues of concern regarding this paper (Savory et al., 2017).
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Affiliation(s)
- Danny Vereecke
- Department of Applied Biosciences, Ghent University, Ghent, Belgium
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48
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Tarkowská D, Strnad M. Isoprenoid-derived plant signaling molecules: biosynthesis and biological importance. PLANTA 2018; 247:1051-1066. [PMID: 29532163 DOI: 10.1007/s00425-018-2878-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 03/05/2018] [Indexed: 05/23/2023]
Abstract
The present review summarizes current knowledge of the biosynthesis and biological importance of isoprenoid-derived plant signaling compounds. Cellular organisms use chemical signals for intercellular communication to coordinate their growth, development, and responses to environmental cues. The skeletons of majority of plant signaling molecules, mediators of plant intercellular 'broadcasting', are built from C5 units of isoprene and therefore belong to a huge and diverse group of natural substances called isoprenoids (terpenoids). They fill many important roles in nature. This review summarizes current knowledge of the biosynthesis and biological importance of a group of isoprenoid-derived plant signaling compounds.
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Affiliation(s)
- Danuše Tarkowská
- Laboratory of Growth Regulators, Faculty of Science, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany AS CR, Palacký University, Šlechtitelů 27, 78371, Olomouc, Czechia.
| | - Miroslav Strnad
- Laboratory of Growth Regulators, Faculty of Science, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany AS CR, Palacký University, Šlechtitelů 27, 78371, Olomouc, Czechia
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49
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Tarkowská D, Strnad M. Isoprenoid-derived plant signaling molecules: biosynthesis and biological importance. PLANTA 2018; 247:1051-1066. [PMID: 29532163 DOI: 10.1007/s00425-018-2878] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 03/05/2018] [Indexed: 05/18/2023]
Abstract
The present review summarizes current knowledge of the biosynthesis and biological importance of isoprenoid-derived plant signaling compounds. Cellular organisms use chemical signals for intercellular communication to coordinate their growth, development, and responses to environmental cues. The skeletons of majority of plant signaling molecules, mediators of plant intercellular 'broadcasting', are built from C5 units of isoprene and therefore belong to a huge and diverse group of natural substances called isoprenoids (terpenoids). They fill many important roles in nature. This review summarizes current knowledge of the biosynthesis and biological importance of a group of isoprenoid-derived plant signaling compounds.
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Affiliation(s)
- Danuše Tarkowská
- Laboratory of Growth Regulators, Faculty of Science, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany AS CR, Palacký University, Šlechtitelů 27, 78371, Olomouc, Czechia.
| | - Miroslav Strnad
- Laboratory of Growth Regulators, Faculty of Science, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany AS CR, Palacký University, Šlechtitelů 27, 78371, Olomouc, Czechia
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Dolzblasz A, Banasiak A, Vereecke D. Neovascularization during leafy gall formation on Arabidopsis thaliana upon Rhodococcus fascians infection. PLANTA 2018; 247:215-228. [PMID: 28942496 DOI: 10.1007/s00425-017-2778-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Accepted: 07/24/2017] [Indexed: 06/07/2023]
Abstract
Extensive de novo vascularization of leafy galls emerging upon Rhodococcus fascians infection is achieved by fascicular/interfascicular cambium activity and transdifferentiation of parenchyma cells correlated with increased auxin signaling. A leafy gall consisting of fully developed yet growth-inhibited shoots, induced by the actinomycete Rhodococcus fascians, differs in structure compared to the callus-like galls induced by other bacteria. To get insight into the vascular development accompanying the emergence of the leafy gall, the anatomy of infected axillary regions of the inflorescence stem of wild-type Arabidopsis thaliana accession Col-0 plants and the auxin response in pDR5:GUS-tagged plants were followed in time. Based on our observations, three phases can be discerned during vascularization of the symptomatic tissue. First, existing fascicular cambium becomes activated and interfascicular cambium is formed giving rise to secondary vascular elements in a basipetal direction below the infection site in the main stem and in an acropetal direction in the entire side branch. Then, parenchyma cells in the region between both stems transdifferentiate acropetally towards the surface of the developing symptomatic tissue leading to the formation of xylem and vascularize the hyperplasia as they expand. Finally, parenchyma cells in the developing gall also transdifferentiate to vascular elements without any specific direction resulting in excessive vasculature disorderly distributed in the leafy gall. Prior to any apparent anatomical changes, a strong auxin response is mounted, implying that auxin is the signal that controls the vascular differentiation induced by the infection. To conclude, we propose the "sidetracking gall hypothesis" as we discuss the mechanisms driving the formation of superfluous vasculature of the emerging leafy gall.
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Affiliation(s)
- Alicja Dolzblasz
- Department of Plant Developmental Biology, Faculty of Biological Sciences, Institute of Experimental Biology, University of Wroclaw, Wroclaw, Poland.
| | - Alicja Banasiak
- Department of Plant Developmental Biology, Faculty of Biological Sciences, Institute of Experimental Biology, University of Wroclaw, Wroclaw, Poland
| | - Danny Vereecke
- Department of Applied Biosciences, Ghent University, Ghent, Belgium.
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