1001
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Xin XF, He SY. Pseudomonas syringae pv. tomato DC3000: a model pathogen for probing disease susceptibility and hormone signaling in plants. ANNUAL REVIEW OF PHYTOPATHOLOGY 2013; 51:473-98. [PMID: 23725467 DOI: 10.1146/annurev-phyto-082712-102321] [Citation(s) in RCA: 357] [Impact Index Per Article: 32.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Since the early 1980s, various strains of the gram-negative bacterial pathogen Pseudomonas syringae have been used as models for understanding plant-bacterial interactions. In 1991, a P. syringae pathovar tomato (Pst) strain, DC3000, was reported to infect not only its natural host tomato but also Arabidopsis in the laboratory, a finding that spurred intensive efforts in the subsequent two decades to characterize the molecular mechanisms by which this strain causes disease in plants. Genomic analysis shows that Pst DC3000 carries a large repertoire of potential virulence factors, including proteinaceous effectors that are secreted through the type III secretion system and a polyketide phytotoxin called coronatine, which structurally mimics the plant hormone jasmonate (JA). Study of Pst DC3000 pathogenesis has not only provided several conceptual advances in understanding how a bacterial pathogen employs type III effectors to suppress plant immune responses and promote disease susceptibility but has also facilitated the discovery of the immune function of stomata and key components of JA signaling in plants. The concepts derived from the study of Pst DC3000 pathogenesis may prove useful in understanding pathogenesis mechanisms of other plant pathogens.
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Affiliation(s)
- Xiu-Fang Xin
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824, USA.
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1002
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Kovalchuk A, Keriö S, Oghenekaro AO, Jaber E, Raffaello T, Asiegbu FO. Antimicrobial defenses and resistance in forest trees: challenges and perspectives in a genomic era. ANNUAL REVIEW OF PHYTOPATHOLOGY 2013; 51:221-44. [PMID: 23682916 DOI: 10.1146/annurev-phyto-082712-102307] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Molecular pathology of forest trees for a long time lagged behind parallel studies on agricultural crop pathology. Recent technological advances have significantly contributed to the observed progress in this field. The first powerful impulse was provided by the completion of the black cottonwood genome sequence in 2006. Genomes of several other important tree species will be completed within a short time. Simultaneously, application of transcriptomics and next-generation sequencing (NGS) has resulted in the rapid accumulation of a vast amount of data on molecular interactions between trees and their microbial parasites. This review provides an overview of our current knowledge about these responses of forest trees to their pathogens, highlighting the achievements of the past decade, discussing the current state of the field, and emphasizing the prospects and challenges for the near future.
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Affiliation(s)
- Andriy Kovalchuk
- Department of Forest Sciences, Forest Pathology Research Laboratory, University of Helsinki, 00014 Helsinki, Finland.
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1003
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Mur LAJ, Prats E, Pierre S, Hall MA, Hebelstrup KH. Integrating nitric oxide into salicylic acid and jasmonic acid/ ethylene plant defense pathways. FRONTIERS IN PLANT SCIENCE 2013; 4:215. [PMID: 23818890 PMCID: PMC3694216 DOI: 10.3389/fpls.2013.00215] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 06/05/2013] [Indexed: 05/03/2023]
Abstract
Plant defense against pests and pathogens is known to be conferred by either salicylic acid (SA) or jasmonic acid (JA)/ethylene (ET) pathways, depending on infection or herbivore-grazing strategy. It is well attested that SA and JA/ET pathways are mutually antagonistic allowing defense responses to be tailored to particular biotic stresses. Nitric oxide (NO) has emerged as a major signal influencing resistance mediated by both signaling pathways but no attempt has been made to integrate NO into established SA/JA/ET interactions. NO has been shown to act as an inducer or suppressor of signaling along each pathway. NO will initiate SA biosynthesis and nitrosylate key cysteines on TGA-class transcription factors to aid in the initiation of SA-dependent gene expression. Against this, S-nitrosylation of NONEXPRESSOR OF PATHOGENESIS-RELATED PROTEINS1 (NPR1) will promote the NPR1 oligomerization within the cytoplasm to reduce TGA activation. In JA biosynthesis, NO will initiate the expression of JA biosynthetic enzymes, presumably to over-come any antagonistic effects of SA on JA-mediated transcription. NO will also initiate the expression of ET biosynthetic genes but a suppressive role is also observed in the S-nitrosylation and inhibition of S-adenosylmethionine transferases which provides methyl groups for ET production. Based on these data a model for NO action is proposed but we have also highlighted the need to understand when and how inductive and suppressive steps are used.
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Affiliation(s)
- Luis A. J. Mur
- Molecular Plant Pathology Group, Institute of Environmental and Rural Science, Aberystwyth UniversityAberystwyth, UK
- *Correspondence: Luis A. J. Mur, Molecular Plant Pathology Group, Institute of Environmental and Rural Science, Aberystwyth University, Edward Llwyd Building, Aberystwyth SY23 3DA, UK e-mail:
| | - Elena Prats
- Institute for Sustainable Agriculture, Spanish National Research CouncilCórdoba, Spain
| | - Sandra Pierre
- Molecular Plant Pathology Group, Institute of Environmental and Rural Science, Aberystwyth UniversityAberystwyth, UK
| | - Michael A. Hall
- Molecular Plant Pathology Group, Institute of Environmental and Rural Science, Aberystwyth UniversityAberystwyth, UK
| | - Kim H. Hebelstrup
- Section of Crop Genetics and Biotechnology, Department of Molecular Biology and Genetics Aarhus UniversitySlagelse, Denmark
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1004
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Bioassays for assessing jasmonate-dependent defenses triggered by pathogens, herbivorous insects, or beneficial rhizobacteria. Methods Mol Biol 2013; 1011:35-49. [PMID: 23615986 DOI: 10.1007/978-1-62703-414-2_4] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Jasmonates, together with other plant hormones, are important orchestrators of the plant immune system. The different hormone-controlled signaling pathways cross-communicate in an antagonistic or a synergistic manner, providing the plant with a powerful capacity to finely regulate its immune response. Jasmonic acid (JA) signaling is required for plant resistance to harmful organisms, such as necrotrophic pathogens and herbivorous insects. Furthermore, JA signaling is essential in interactions of plants with beneficial microbes that induce systemic resistance to pathogens and insects. The role of JA signaling components in plant immunity can be studied by performing bioassays with different interacting organisms. Determination of the level of resistance and the induction of defense responses in plants with altered JA components, through mutation or ectopic expression, will unveil novel mechanisms of JA signaling. We provide detailed protocols of bioassays with the model plant Arabidopsis thaliana challenged with the pathogens Botrytis cinerea and Pseudomonas syringae, the insect herbivore Pieris rapae, and the beneficial microbe Pseudomonas fluorescens. In addition, we describe pharmacological assays to study the modulation of JA-regulated responses by exogenous application of combinations of hormones, because a simultaneous rise in hormone levels occurs during interaction of plants with other organisms.
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1005
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Michelmore RW, Christopoulou M, Caldwell KS. Impacts of resistance gene genetics, function, and evolution on a durable future. ANNUAL REVIEW OF PHYTOPATHOLOGY 2013; 51:291-319. [PMID: 23682913 DOI: 10.1146/annurev-phyto-082712-102334] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Studies on resistance gene function and evolution lie at the confluence of structural and molecular biology, genetics, and plant breeding. However, knowledge from these disparate fields has yet to be extensively integrated. This review draws on ideas and information from these different fields to elucidate the influences driving the evolution of different types of resistance genes in plants and the concurrent evolution of virulence in pathogens. It provides an overview of the factors shaping the evolution of recognition, signaling, and response genes in the context of emerging functional information along with a consideration of the new opportunities for durable resistance enabled by high-throughput DNA sequencing technologies.
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1006
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Mur LAJ, Mandon J, Persijn S, Cristescu SM, Moshkov IE, Novikova GV, Hall MA, Harren FJM, Hebelstrup KH, Gupta KJ. Nitric oxide in plants: an assessment of the current state of knowledge. AOB PLANTS 2013; 5:pls052. [PMID: 23372921 PMCID: PMC3560241 DOI: 10.1093/aobpla/pls052] [Citation(s) in RCA: 223] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Accepted: 12/12/2012] [Indexed: 05/18/2023]
Abstract
BACKGROUND AND AIMS After a series of seminal works during the last decade of the 20th century, nitric oxide (NO) is now firmly placed in the pantheon of plant signals. Nitric oxide acts in plant-microbe interactions, responses to abiotic stress, stomatal regulation and a range of developmental processes. By considering the recent advances in plant NO biology, this review will highlight certain key aspects that require further attention. SCOPE AND CONCLUSIONS The following questions will be considered. While cytosolic nitrate reductase is an important source of NO, the contributions of other mechanisms, including a poorly defined arginine oxidizing activity, need to be characterized at the molecular level. Other oxidative pathways utilizing polyamine and hydroxylamine also need further attention. Nitric oxide action is dependent on its concentration and spatial generation patterns. However, no single technology currently available is able to provide accurate in planta measurements of spatio-temporal patterns of NO production. It is also the case that pharmaceutical NO donors are used in studies, sometimes with little consideration of the kinetics of NO production. We here include in planta assessments of NO production from diethylamine nitric oxide, S-nitrosoglutathione and sodium nitroprusside following infiltration of tobacco leaves, which could aid workers in their experiments. Further, based on current data it is difficult to define a bespoke plant NO signalling pathway, but rather NO appears to act as a modifier of other signalling pathways. Thus, early reports that NO signalling involves cGMP-as in animal systems-require revisiting. Finally, as plants are exposed to NO from a number of external sources, investigations into the control of NO scavenging by such as non-symbiotic haemoglobins and other sinks for NO should feature more highly. By crystallizing these questions the authors encourage their resolution through the concerted efforts of the plant NO community.
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Affiliation(s)
- Luis A. J. Mur
- Institute of Environmental and Rural Science, Aberystwyth University, Edward Llwyd Building, Aberystwyth SY23 3DA, UK
- Corresponding author's e-mail address:
| | - Julien Mandon
- Life Science Trace Gas Facility, Molecular and Laser Physics, Institute for Molecules and Materials, Radboud University, PO Box 9010, 6500 GL Nijmegen, The Netherlands
| | - Stefan Persijn
- Life Science Trace Gas Facility, Molecular and Laser Physics, Institute for Molecules and Materials, Radboud University, PO Box 9010, 6500 GL Nijmegen, The Netherlands
| | - Simona M. Cristescu
- Life Science Trace Gas Facility, Molecular and Laser Physics, Institute for Molecules and Materials, Radboud University, PO Box 9010, 6500 GL Nijmegen, The Netherlands
| | - Igor E. Moshkov
- Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, ul. Botanicheskaya 35, Moscow 127276, Russia
| | - Galina V. Novikova
- Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, ul. Botanicheskaya 35, Moscow 127276, Russia
| | - Michael A. Hall
- Institute of Environmental and Rural Science, Aberystwyth University, Edward Llwyd Building, Aberystwyth SY23 3DA, UK
| | - Frans J. M. Harren
- Life Science Trace Gas Facility, Molecular and Laser Physics, Institute for Molecules and Materials, Radboud University, PO Box 9010, 6500 GL Nijmegen, The Netherlands
| | - Kim H. Hebelstrup
- Department of Molecular Biology and Genetics, Section of Crop Genetics and Biotechnology, Aarhus University, Forsøgsvej 1, DK-4200 Slagelse, Denmark
| | - Kapuganti J. Gupta
- Department of Plant Sciences, University of Oxford, South Parks Road, Oxford OX1 3RB, UK
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1007
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Abstract
Ilarviruses were among the first 16 groups of plant viruses approved by ICTV. Like Alfalfa mosaic virus (AMV), bromoviruses, and cucumoviruses they are isometric viruses and possess a single-stranded, tripartite RNA genome. However, unlike these other three groups, ilarviruses were recognized as being recalcitrant subjects for research (their ready lability is reflected in the sigla used to create the group name) and were renowned as unpromising subjects for the production of antisera. However, it was recognized that they shared properties with AMV when the phenomenon of genome activation, in which the coat protein (CP) of the virus is required to be present to initiate infection, was demonstrated to cross group boundaries. The CP of AMV could activate the genome of an ilarvirus and vice versa. Development of the molecular information for ilarviruses lagged behind the knowledge available for the more extensively studied AMV, bromoviruses, and cucumoviruses. In the past 20 years, genomic data for most known ilarviruses have been developed facilitating their detection and allowing the factors involved in the molecular biology of the genus to be investigated. Much information has been obtained using Prunus necrotic ringspot virus and the more extensively studied AMV. A relationship between some ilarviruses and the cucumoviruses has been defined with the recognition that members of both genera encode a 2b protein involved in RNA silencing and long distance viral movement. Here, we present a review of the current knowledge of both the taxonomy and the molecular biology of this genus of agronomically and horticulturally important viruses.
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1008
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Dorantes-Acosta AE, Sánchez-Hernández CV, Arteaga-Vázquez MA. Biotic stress in plants: life lessons from your parents and grandparents. Front Genet 2012; 3:256. [PMID: 23230448 PMCID: PMC3515780 DOI: 10.3389/fgene.2012.00256] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Accepted: 10/31/2012] [Indexed: 12/27/2022] Open
Affiliation(s)
- A E Dorantes-Acosta
- Laboratorio de Epigenética y Biología del Desarrollo, Instituto de Biotecnología y Ecología Aplicada(INBIOTECA), Universidad Veracruzana. Xalapa, Veracruz. México
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1009
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Abstract
Ethylene (ET) is a gaseous phytohormone that participates in various plant physiological processes and essentially contributes to plant immunity. ET conducts its functions by regulating the expression of ET-responsive genes or in crosstalk with other hormones. Several recent studies have shown the significance of ET in the establishment and development of plant-microbe interactions. Therefore, it is not surprising that pathogens and mutualistic symbionts target ET synthesis or signaling to colonize plants. This review introduces the significance of ET metabolism in plant-microbe interactions, with an emphasis on its role in mutualistic symbioses.
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Affiliation(s)
- Behnam Khatabi
- Department of Entomology and Plant Pathology; University of Tennessee; Knoxville, TN USA
| | - Patrick Schäfer
- School of Life Sciences; University of Warwick; Coventry, UK
- Correspondence to: Patrick Schäfer,
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1010
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Gu XC, Chen JF, Xiao Y, Di P, Xuan HJ, Zhou X, Zhang L, Chen WS. Overexpression of allene oxide cyclase promoted tanshinone/phenolic acid production in Salvia miltiorrhiza. PLANT CELL REPORTS 2012; 31:2247-59. [PMID: 22926031 DOI: 10.1007/s00299-012-1334-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2012] [Revised: 08/01/2012] [Accepted: 08/08/2012] [Indexed: 05/08/2023]
Abstract
KEY MESSAGE This study provides a desirable candidate gene resource (SmAOC) to increase the content of valuable natural products via appropriate JA pathway genetic engineering. Jasmonates (JAs) are important signal molecules in plants. They regulate transcripts of defense and secondary biosynthetic metabolite genes in response to environmental stresses. Currently, JAs are widely used as elicitors to improve the content of useful secondary metabolism in plants. Synthesis of the naturally occurring enantiomer of various jasmonates is catalyzed by allene oxide cyclase (AOC, EC 5.3.99.6). Here, we cloned and characterized the AOC gene (SmAOC) from Salvia miltiorrhiza. As expected, SmAOC expression was induced by abiotic stimuli such as methyl jasmonate (MeJA), ultraviolet radiation (UV) and low temperature (4 °C) in S. miltiorrhiza plantlets. To demonstrate whether the engineered internal JAs pool by overexpressing AOC gene could promote secondary metabolism production, the SmAOC was incorporated into S. miltiorrhiza hairy roots. The results revealed that SmAOC overexpression significant enhanced the yields of tanshinone IIA, rosmarinic acid (RA) and lithospermic acid B (LAB) in S. miltiorrhiza hairy roots. In addition, expression levels for key genes involved in the biosynthetic pathway of diterpenes and phenolic acids were also altered. These suggest that genetic manipulation of AOC would be helpful for improving the production of valuable secondary metabolites by regulating the biosynthesis of JAs.
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Affiliation(s)
- Xiao-Ce Gu
- Department of Pharmacy, Changzheng Hospital, Second Military Medical University, Shanghai 200003, People's Republic of China
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1011
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Botanga CJ, Bethke G, Chen Z, Gallie DR, Fiehn O, Glazebrook J. Metabolite profiling of Arabidopsis inoculated with Alternaria brassicicola reveals that ascorbate reduces disease severity. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2012; 25:1628-38. [PMID: 23134520 DOI: 10.1094/mpmi-07-12-0179-r] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The interaction between the pathogenic ascomycete Alternaria brassicicola and Arabidopsis was investigated by metabolite profiling. The effect of A. brassicicola challenge on metabolite levels was substantial, with nearly 50% of detected compounds undergoing significant changes. Mutations blocking ethylene, jasmonic acid, or ethylene signaling had little effect on metabolite levels. The effects of altering levels of some metabolites were tested by exogenous application during A. brassicicola inoculation. Gamma amino-butyric acid (GABA) or xylitol promoted, while trehalose and ascorbate inhibited, disease severity. GABA promoted, and ascorbate strongly inhibited, fungal growth in culture. Arabidopsis vtc1 and vtc2 mutants, that have low levels of ascorbate, were more susceptible to A. brassicicola. Ascorbate levels declined following A. brassicicola inoculation while levels of dehydroascorbate increased, resulting in a shift of the redox balance between these compounds in the direction of oxidation. These results demonstrate that ascorbate is an important component of resistance to this pathogen.
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1012
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Sánchez-Vallet A, López G, Ramos B, Delgado-Cerezo M, Riviere MP, Llorente F, Fernández PV, Miedes E, Estevez JM, Grant M, Molina A. Disruption of abscisic acid signaling constitutively activates Arabidopsis resistance to the necrotrophic fungus Plectosphaerella cucumerina. PLANT PHYSIOLOGY 2012; 160:2109-24. [PMID: 23037505 PMCID: PMC3510135 DOI: 10.1104/pp.112.200154] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2012] [Accepted: 10/01/2012] [Indexed: 05/20/2023]
Abstract
Plant resistance to necrotrophic fungi is regulated by a complex set of signaling pathways that includes those mediated by the hormones salicylic acid (SA), ethylene (ET), jasmonic acid (JA), and abscisic acid (ABA). The role of ABA in plant resistance remains controversial, as positive and negative regulatory functions have been described depending on the plant-pathogen interaction analyzed. Here, we show that ABA signaling negatively regulates Arabidopsis (Arabidopsis thaliana) resistance to the necrotrophic fungus Plectosphaerella cucumerina. Arabidopsis plants impaired in ABA biosynthesis, such as the aba1-6 mutant, or in ABA signaling, like the quadruple pyr/pyl mutant (pyr1pyl1pyl2pyl4), were more resistant to P. cucumerina than wild-type plants. In contrast, the hab1-1abi1-2abi2-2 mutant impaired in three phosphatases that negatively regulate ABA signaling displayed an enhanced susceptibility phenotype to this fungus. Comparative transcriptomic analyses of aba1-6 and wild-type plants revealed that the ABA pathway negatively regulates defense genes, many of which are controlled by the SA, JA, or ET pathway. In line with these data, we found that aba1-6 resistance to P. cucumerina was partially compromised when the SA, JA, or ET pathway was disrupted in this mutant. Additionally, in the aba1-6 plants, some genes encoding cell wall-related proteins were misregulated. Fourier transform infrared spectroscopy and biochemical analyses of cell walls from aba1-6 and wild-type plants revealed significant differences in their Fourier transform infrared spectratypes and uronic acid and cellulose contents. All these data suggest that ABA signaling has a complex function in Arabidopsis basal resistance, negatively regulating SA/JA/ET-mediated resistance to necrotrophic fungi.
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1013
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Meldau S, Erb M, Baldwin IT. Defence on demand: mechanisms behind optimal defence patterns. ANNALS OF BOTANY 2012; 110:1503-14. [PMID: 23022676 PMCID: PMC3503495 DOI: 10.1093/aob/mcs212] [Citation(s) in RCA: 112] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Accepted: 08/22/2012] [Indexed: 05/20/2023]
Abstract
BACKGROUND The optimal defence hypothesis (ODH) predicts that tissues that contribute most to a plant's fitness and have the highest probability of being attacked will be the parts best defended against biotic threats, including herbivores. In general, young sink tissues and reproductive structures show stronger induced defence responses after attack from pathogens and herbivores and contain higher basal levels of specialized defensive metabolites than other plant parts. However, the underlying physiological mechanisms responsible for these developmentally regulated defence patterns remain unknown. SCOPE This review summarizes current knowledge about optimal defence patterns in above- and below-ground plant tissues, including information on basal and induced defence metabolite accumulation, defensive structures and their regulation by jasmonic acid (JA). Physiological regulations underlying developmental differences of tissues with contrasting defence patterns are highlighted, with a special focus on the role of classical plant growth hormones, including auxins, cytokinins, gibberellins and brassinosteroids, and their interactions with the JA pathway. By synthesizing recent findings about the dual roles of these growth hormones in plant development and defence responses, this review aims to provide a framework for new discoveries on the molecular basis of patterns predicted by the ODH. CONCLUSIONS Almost four decades after its formulation, we are just beginning to understand the underlying molecular mechanisms responsible for the patterns of defence allocation predicted by the ODH. A requirement for future advances will be to understand how developmental and defence processes are integrated.
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Affiliation(s)
- Stefan Meldau
- Department of Molecular Ecology, Max-Planck-Institute for Chemical Ecology, Jena, Germany.
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1014
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Affiliation(s)
| | - Thomas Dandekar
- Department of Bioinformatics, University of Würzburg, Würzburg, Germany
- * E-mail:
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1015
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Pieterse CM, Van der Does D, Zamioudis C, Leon-Reyes A, Van Wees SC. Hormonal Modulation of Plant Immunity. Annu Rev Cell Dev Biol 2012; 28:489-521. [DOI: 10.1146/annurev-cellbio-092910-154055] [Citation(s) in RCA: 1753] [Impact Index Per Article: 146.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Corné M.J. Pieterse
- Plant-Microbe Interactions, Institute of Environmental Biology, Department of Biology, Faculty of Science, Utrecht University, 3508 TB Utrecht, The Netherlands; , , ,
- Centre for BioSystems Genomics, 6700 AB Wageningen, The Netherlands
| | - Dieuwertje Van der Does
- Plant-Microbe Interactions, Institute of Environmental Biology, Department of Biology, Faculty of Science, Utrecht University, 3508 TB Utrecht, The Netherlands; , , ,
| | - Christos Zamioudis
- Plant-Microbe Interactions, Institute of Environmental Biology, Department of Biology, Faculty of Science, Utrecht University, 3508 TB Utrecht, The Netherlands; , , ,
| | - Antonio Leon-Reyes
- Laboratorio de Biotecnología Agrícola y de Alimentos, Universidad San Francisco de Quito, Quito, Ecuador;
| | - Saskia C.M. Van Wees
- Plant-Microbe Interactions, Institute of Environmental Biology, Department of Biology, Faculty of Science, Utrecht University, 3508 TB Utrecht, The Netherlands; , , ,
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1016
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Sanchez L, Courteaux B, Hubert J, Kauffmann S, Renault JH, Clément C, Baillieul F, Dorey S. Rhamnolipids elicit defense responses and induce disease resistance against biotrophic, hemibiotrophic, and necrotrophic pathogens that require different signaling pathways in Arabidopsis and highlight a central role for salicylic acid. PLANT PHYSIOLOGY 2012; 160:1630-41. [PMID: 22968829 PMCID: PMC3490604 DOI: 10.1104/pp.112.201913] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2012] [Accepted: 09/06/2012] [Indexed: 05/19/2023]
Abstract
Plant resistance to phytopathogenic microorganisms mainly relies on the activation of an innate immune response usually launched after recognition by the plant cells of microbe-associated molecular patterns. The plant hormones, salicylic acid (SA), jasmonic acid, and ethylene have emerged as key players in the signaling networks involved in plant immunity. Rhamnolipids (RLs) are glycolipids produced by bacteria and are involved in surface motility and biofilm development. Here we report that RLs trigger an immune response in Arabidopsis (Arabidopsis thaliana) characterized by signaling molecules accumulation and defense gene activation. This immune response participates to resistance against the hemibiotrophic bacterium Pseudomonas syringae pv tomato, the biotrophic oomycete Hyaloperonospora arabidopsidis, and the necrotrophic fungus Botrytis cinerea. We show that RL-mediated resistance involves different signaling pathways that depend on the type of pathogen. Ethylene is involved in RL-induced resistance to H. arabidopsidis and to P. syringae pv tomato whereas jasmonic acid is essential for the resistance to B. cinerea. SA participates to the restriction of all pathogens. We also show evidence that SA-dependent plant defenses are potentiated by RLs following challenge by B. cinerea or P. syringae pv tomato. These results highlight a central role for SA in RL-mediated resistance. In addition to the activation of plant defense responses, antimicrobial properties of RLs are thought to participate in the protection against the fungus and the oomycete. Our data highlight the intricate mechanisms involved in plant protection triggered by a new type of molecule that can be perceived by plant cells and that can also act directly onto pathogens.
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Affiliation(s)
- Lisa Sanchez
- Laboratoire de Stress, Défenses, et Reproduction des Plantes, L'Unité de Recherche Vignes et Vins de Champagne, Equipe d'Accueil 4707 (L.S., B.C., C.C., F.B., S.D.) and Institut de Chimie Moléculaire de Reims Unité Mixte de Recherche, Centre National de la Recherche Scientifique 6229, Institut Fédératif Recherche 53 (J.H., J.-H.R.), Université de Reims Champagne-Ardenne, F-51687 Reims cedex 2, France; and Institut de Biologie Moléculaire des Plantes, Centre National de la Recherche Scientifique, Unité Propre de Recherche 2357, F-67084 Strasbourg, France (S.K.)
| | - Barbara Courteaux
- Laboratoire de Stress, Défenses, et Reproduction des Plantes, L'Unité de Recherche Vignes et Vins de Champagne, Equipe d'Accueil 4707 (L.S., B.C., C.C., F.B., S.D.) and Institut de Chimie Moléculaire de Reims Unité Mixte de Recherche, Centre National de la Recherche Scientifique 6229, Institut Fédératif Recherche 53 (J.H., J.-H.R.), Université de Reims Champagne-Ardenne, F-51687 Reims cedex 2, France; and Institut de Biologie Moléculaire des Plantes, Centre National de la Recherche Scientifique, Unité Propre de Recherche 2357, F-67084 Strasbourg, France (S.K.)
| | - Jane Hubert
- Laboratoire de Stress, Défenses, et Reproduction des Plantes, L'Unité de Recherche Vignes et Vins de Champagne, Equipe d'Accueil 4707 (L.S., B.C., C.C., F.B., S.D.) and Institut de Chimie Moléculaire de Reims Unité Mixte de Recherche, Centre National de la Recherche Scientifique 6229, Institut Fédératif Recherche 53 (J.H., J.-H.R.), Université de Reims Champagne-Ardenne, F-51687 Reims cedex 2, France; and Institut de Biologie Moléculaire des Plantes, Centre National de la Recherche Scientifique, Unité Propre de Recherche 2357, F-67084 Strasbourg, France (S.K.)
| | | | - Jean-Hugues Renault
- Laboratoire de Stress, Défenses, et Reproduction des Plantes, L'Unité de Recherche Vignes et Vins de Champagne, Equipe d'Accueil 4707 (L.S., B.C., C.C., F.B., S.D.) and Institut de Chimie Moléculaire de Reims Unité Mixte de Recherche, Centre National de la Recherche Scientifique 6229, Institut Fédératif Recherche 53 (J.H., J.-H.R.), Université de Reims Champagne-Ardenne, F-51687 Reims cedex 2, France; and Institut de Biologie Moléculaire des Plantes, Centre National de la Recherche Scientifique, Unité Propre de Recherche 2357, F-67084 Strasbourg, France (S.K.)
| | - Christophe Clément
- Laboratoire de Stress, Défenses, et Reproduction des Plantes, L'Unité de Recherche Vignes et Vins de Champagne, Equipe d'Accueil 4707 (L.S., B.C., C.C., F.B., S.D.) and Institut de Chimie Moléculaire de Reims Unité Mixte de Recherche, Centre National de la Recherche Scientifique 6229, Institut Fédératif Recherche 53 (J.H., J.-H.R.), Université de Reims Champagne-Ardenne, F-51687 Reims cedex 2, France; and Institut de Biologie Moléculaire des Plantes, Centre National de la Recherche Scientifique, Unité Propre de Recherche 2357, F-67084 Strasbourg, France (S.K.)
| | - Fabienne Baillieul
- Laboratoire de Stress, Défenses, et Reproduction des Plantes, L'Unité de Recherche Vignes et Vins de Champagne, Equipe d'Accueil 4707 (L.S., B.C., C.C., F.B., S.D.) and Institut de Chimie Moléculaire de Reims Unité Mixte de Recherche, Centre National de la Recherche Scientifique 6229, Institut Fédératif Recherche 53 (J.H., J.-H.R.), Université de Reims Champagne-Ardenne, F-51687 Reims cedex 2, France; and Institut de Biologie Moléculaire des Plantes, Centre National de la Recherche Scientifique, Unité Propre de Recherche 2357, F-67084 Strasbourg, France (S.K.)
| | - Stéphan Dorey
- Laboratoire de Stress, Défenses, et Reproduction des Plantes, L'Unité de Recherche Vignes et Vins de Champagne, Equipe d'Accueil 4707 (L.S., B.C., C.C., F.B., S.D.) and Institut de Chimie Moléculaire de Reims Unité Mixte de Recherche, Centre National de la Recherche Scientifique 6229, Institut Fédératif Recherche 53 (J.H., J.-H.R.), Université de Reims Champagne-Ardenne, F-51687 Reims cedex 2, France; and Institut de Biologie Moléculaire des Plantes, Centre National de la Recherche Scientifique, Unité Propre de Recherche 2357, F-67084 Strasbourg, France (S.K.)
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1017
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Shearer HL, Cheng YT, Wang L, Liu J, Boyle P, Després C, Zhang Y, Li X, Fobert PR. Arabidopsis clade I TGA transcription factors regulate plant defenses in an NPR1-independent fashion. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2012; 25:1459-68. [PMID: 22876961 DOI: 10.1094/mpmi-09-11-0256] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Transcriptional reprogramming during induction of salicylic acid (SA)-mediated defenses is regulated primarily by NPR1 (NONEXPRESSOR OF PATHOGENESIS-RELATED GENES 1), likely through interactions with TGA bZIP transcription factors. To ascertain the contributions of clade I TGA factors (TGA1 and TGA4) to defense responses, a tga1-1 tga4-1 double mutant was constructed and challenged with Pseudomonas syringae and Hyaloperonospora arabidopsidis. Although the mutant displayed enhanced susceptibility to virulent P. syringae, it was not compromised in systemic acquired resistance against this pathogen or resistance against avirulent H. arabidopsidis. Microarray analysis of nonelicited and SA-treated plants indicated that clade I TGA factors regulate fewer genes than NPR1. Approximately half of TGA-dependent genes were regulated by NPR1 but, in all cases, the direction of change was opposite in the two mutants. In support of the microarray data, the NPR1-independent disease resistance observed in the autoimmune resistance (R) gene mutant snc1 is partly compromised by tga1-1 tga4-1 mutations, and a triple mutant of clade I TGA factors with npr1-1 is more susceptible than either parent. These results suggest that clade I TGA factors are required for resistance against virulent pathogens and avirulent pathogens mediated by at least some R gene specificities, acting substantially through NPR1-independent pathways.
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1018
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Gutzat R, Mittelsten Scheid O. Epigenetic responses to stress: triple defense? CURRENT OPINION IN PLANT BIOLOGY 2012; 15:568-73. [PMID: 22960026 PMCID: PMC3508409 DOI: 10.1016/j.pbi.2012.08.007] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Accepted: 08/16/2012] [Indexed: 05/19/2023]
Abstract
Stressful conditions for plants can originate from numerous physical, chemical and biological factors, and plants have developed a plethora of survival strategies including developmental and morphological adaptations, specific signaling and defense pathways as well as innate and acquired immunity. While it has become clear in recent years that many stress responses involve epigenetic components, we are far from understanding the mechanisms and molecular interactions. Extending our knowledge is fundamental, not least for plant breeding and conservation biology. This review will highlight recent insights into epigenetic stress responses at the level of signaling, chromatin modification, and potentially heritable consequences.
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1019
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Nahar K, Kyndt T, Nzogela YB, Gheysen G. Abscisic acid interacts antagonistically with classical defense pathways in rice-migratory nematode interaction. THE NEW PHYTOLOGIST 2012; 196:901-913. [PMID: 22985247 DOI: 10.1111/j.1469-8137.2012.04310.x] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Accepted: 07/30/2012] [Indexed: 05/08/2023]
Abstract
Studies involving plant-nematode interactions provide an opportunity to unravel plant defense signaling in root tissues. In this study, we have characterized the roles of salicylate (SA), jasmonate (JA), ethylene (ET) and abscisic acid (ABA) in plant defense against the migratory nematode Hirschmanniella oryzae in the monocot model plant rice (Oryza sativa). Experiments with exogenous hormone applications, biosynthesis inhibition and mutant/transgenic lines were executed to test the effect on H. oryzae parasitism in rice roots. Our results demonstrate that an intact ET, JA and SA biosynthesis pathway is a prerequisite for defense against H. oryzae. By contrast, exogenous ABA treatment drastically compromised the rice defense towards this nematode. Gene expression analyses using quantitative reverse transcription polymerase chain reaction (qRT-PCR) demonstrate that the disease-inducing effect of ABA is likely to be the result of an antagonistic interaction between this hormone and the SA/JA/ET-dependent basal defense system. Collectively, in rice defense against H. oryzae, at least three pathways, namely SA, JA and ET, are important, while ABA plays a negative role in defense. Our results suggest that the balance of ABA and SA/JA/ET signaling is an important determinant for the outcome of the rice-H. oryzae interaction.
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Affiliation(s)
- Kamrun Nahar
- Department of Molecular Biotechnology, Ghent University, Coupure links 653, B-9000, Ghent, Belgium
| | - Tina Kyndt
- Department of Molecular Biotechnology, Ghent University, Coupure links 653, B-9000, Ghent, Belgium
| | - Yasinta Beda Nzogela
- Department of Molecular Biotechnology, Ghent University, Coupure links 653, B-9000, Ghent, Belgium
| | - Godelieve Gheysen
- Department of Molecular Biotechnology, Ghent University, Coupure links 653, B-9000, Ghent, Belgium
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1020
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Xia Y, Yu K, Gao QM, Wilson EV, Navarre D, Kachroo P, Kachroo A. Acyl CoA Binding Proteins are Required for Cuticle Formation and Plant Responses to Microbes. FRONTIERS IN PLANT SCIENCE 2012; 3:224. [PMID: 23060893 PMCID: PMC3465942 DOI: 10.3389/fpls.2012.00224] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2012] [Accepted: 09/17/2012] [Indexed: 05/18/2023]
Abstract
Fatty acids (FA) and lipids are well known regulators of plant defense. Our previous studies have shown that components of prokaryotic (plastidal) FA biosynthesis pathway regulate various aspects of plant defense. Here, we investigated the defense related roles of the soluble acyl CoA binding proteins (ACBPs), which are thought to facilitate the intracellular transport of FA/lipids. We show that ACBP3 and 4 are required for maintaining normal lipid levels and that ACBP3 contributes to the lipid flux between the prokaryotic and eukaryotic pathways. We also show that loss of ACBP3, 4, or 6 impair normal development of the cuticle and affect both basal and resistance protein-mediated defense against bacterial and fungal pathogens. Loss of ACBP3, 4, or 6 also inhibits the induction of systemic acquired resistance (SAR) due to the plants inability to generate SAR inducing signal(s). Together, these data show that ACBP3, ACBP4, and ACBP6 are required for cuticle development as well as defense against microbial pathogens.
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Affiliation(s)
- Ye Xia
- Department of Plant Pathology, University of KentuckyLexington, KY, USA
| | - Keshun Yu
- Department of Plant Pathology, University of KentuckyLexington, KY, USA
| | - Qing-ming Gao
- Department of Plant Pathology, University of KentuckyLexington, KY, USA
| | - Ella V. Wilson
- Department of Plant Pathology, University of KentuckyLexington, KY, USA
| | - Duroy Navarre
- U.S. Department of Agriculture, Agricultural Research Service, Washington State UniversityProsser, WA, USA
| | - Pradeep Kachroo
- Department of Plant Pathology, University of KentuckyLexington, KY, USA
| | - Aardra Kachroo
- Department of Plant Pathology, University of KentuckyLexington, KY, USA
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1021
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Mair A, Teige M. Shaping the pathogen response by protein kinase triggered oxidative burst. THE NEW PHYTOLOGIST 2012; 196:4-6. [PMID: 22924402 DOI: 10.1111/j.1469-8137.2012.04293.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Affiliation(s)
- Andrea Mair
- Department of Molecular Systems Biology, University of Vienna, Althanstr. 14, 1090, Vienna, Austria
| | - Markus Teige
- Department of Molecular Systems Biology, University of Vienna, Althanstr. 14, 1090, Vienna, Austria
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1022
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Hilbert M, Voll LM, Ding Y, Hofmann J, Sharma M, Zuccaro A. Indole derivative production by the root endophyte Piriformospora indica is not required for growth promotion but for biotrophic colonization of barley roots. THE NEW PHYTOLOGIST 2012; 196:520-534. [PMID: 22924530 DOI: 10.1111/j.1469-8137.2012.04275.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2012] [Accepted: 07/07/2012] [Indexed: 05/04/2023]
Abstract
Beneficial effects elicited by the root endophyte Piriformospora indica are widely known, but the mechanism by which these are achieved is still unclear. It is proposed that phytohormones produced by the fungal symbiont play a crucial role in the interaction with the plant roots. Biochemical analyses of the underlying biosynthetic pathways for auxin production have shown that, on tryptophan feeding, P. indica can produce the phytohormones indole-3-acetic acid (IAA) and indole-3-lactate (ILA) through the intermediate indole-3-pyruvic acid (IPA). Time course transcriptional analyses after exposure to tryptophan designated the piTam1 gene as a key player. A green fluorescence protein (GFP) reporter study and transcriptional analysis of colonized barley roots showed that piTam1 is induced during the biotrophic phase. Piriformospora indica strains in which the piTam1 gene was silenced via an RNA interference (RNAi) approach were compromised in IAA and ILA production and displayed reduced colonization of barley (Hordeum vulgare) roots in the biotrophic phase, but the elicitation of growth promotion was not affected compared with the wild-type situation. Our results suggest that IAA is involved in the establishment of biotrophy in P. indica-barley symbiosis and might represent a compatibility factor in this system.
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Affiliation(s)
- Magdalena Hilbert
- Department of Organismic Interactions, Max Planck Institute for Terrestrial Microbiology, Karl von Frisch Str. 10, 35043, Marburg, Germany
| | - Lars M Voll
- Department of Biology, Friedrich-Alexander University Erlangen-Nürnberg, Staudtstr. 5, 91058, Erlangen, Germany
| | - Yi Ding
- Department of Organismic Interactions, Max Planck Institute for Terrestrial Microbiology, Karl von Frisch Str. 10, 35043, Marburg, Germany
| | - Jörg Hofmann
- Department of Biology, Friedrich-Alexander University Erlangen-Nürnberg, Staudtstr. 5, 91058, Erlangen, Germany
| | - Monica Sharma
- Department of Mycology and Plant Pathology, Dr. YSP UHF, Nauni, Solan, HP, India
| | - Alga Zuccaro
- Department of Organismic Interactions, Max Planck Institute for Terrestrial Microbiology, Karl von Frisch Str. 10, 35043, Marburg, Germany
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1023
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Garcia AV, Al-Yousif M, Hirt H. Role of AGC kinases in plant growth and stress responses. Cell Mol Life Sci 2012; 69:3259-67. [PMID: 22847330 PMCID: PMC11114936 DOI: 10.1007/s00018-012-1093-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2012] [Revised: 07/09/2012] [Accepted: 07/09/2012] [Indexed: 12/20/2022]
Abstract
AGC kinases are important regulators of cell growth, metabolism, division, and survival in mammalian systems. Mutation or deregulation of members of this family of protein kinases contribute to the pathogenesis of many human diseases, including cancer and diabetes. Although AGC kinases are conserved in the plant kingdom, little is known about their molecular functions and targets. Some of the best-studied plant AGC kinases mediate auxin signaling and are thereby involved in the regulation of growth and morphogenesis. Furthermore, certain members are regulated by lipid-derived signals via the 3-phosphoinositide-dependent kinase 1 (PDK1) and the kinase target of rapamycin (TOR), similar to its animal counterparts. In this review, we discuss recent findings on plant AGC kinases that unravel important roles in the regulation of plant growth, immunity and cell death, and connections to stress-induced mitogen-activated protein kinase signaling cascades.
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Affiliation(s)
- Ana Victoria Garcia
- URGV Unité de Recherche en Génomique Végétale, UMR1165, ERL8196, INRA-UEVE-CNRS, 91057 Evry, France
| | | | - Heribert Hirt
- URGV Unité de Recherche en Génomique Végétale, UMR1165, ERL8196, INRA-UEVE-CNRS, 91057 Evry, France
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1024
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Zhou C, Han L, Fu C, Chai M, Zhang W, Li G, Tang Y, Wang ZY. Identification and characterization of petiolule-like pulvinus mutants with abolished nyctinastic leaf movement in the model legume Medicago truncatula. THE NEW PHYTOLOGIST 2012; 196:92-100. [PMID: 22891817 PMCID: PMC3504090 DOI: 10.1111/j.1469-8137.2012.04268.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Accepted: 07/10/2012] [Indexed: 05/21/2023]
Abstract
Leaves of many plant species open during the day and fold at night. Diurnal leaf movement, named nyctinasty, has been of great interest to researchers since Darwin's time. Nyctinastic leaf movement is generated by the pulvinus, which is a specialized motor organ located at the base of leaf and leaflet. The molecular basis and functional reason behind nyctinasty are unknown. In a forward screening of a retrotransposon-tagged mutant population of Medicago truncatula, four petiolule-like pulvinus (plp) mutant lines with defects in leaf movement were identified and characterized. Loss of function of PLP results in the change of pulvini to petiolules. PLP is specifically expressed in the pulvinus, as demonstrated by quantitative reverse-transcription polymerase chain reaction analysis, expression analysis of a PLP promoter-β-glucuronidase construct in transgenic plants and in situ hybridization. Microarray analysis revealed that the expression levels of many genes were altered in the mutant during the day and at night. Crosses between the plp mutant and several leaf pattern mutants showed that the developmental mechanisms of pulvini and leaf patterns are likely independent. Our results demonstrated that PLP plays a crucial role in the determination of pulvinus development. Leaf movement generated by pulvini may have an impact on plant vegetative growth.
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Affiliation(s)
- Chuanen Zhou
- Forage Improvement Division, The Samuel Roberts Noble Foundation2510 Sam Noble Parkway, Ardmore, OK, 73401, USA
| | - Lu Han
- Forage Improvement Division, The Samuel Roberts Noble Foundation2510 Sam Noble Parkway, Ardmore, OK, 73401, USA
| | - Chunxiang Fu
- Forage Improvement Division, The Samuel Roberts Noble Foundation2510 Sam Noble Parkway, Ardmore, OK, 73401, USA
| | - Maofeng Chai
- Forage Improvement Division, The Samuel Roberts Noble Foundation2510 Sam Noble Parkway, Ardmore, OK, 73401, USA
| | - Wenzheng Zhang
- Forage Improvement Division, The Samuel Roberts Noble Foundation2510 Sam Noble Parkway, Ardmore, OK, 73401, USA
| | - Guifen Li
- Plant Biology Division, The Samuel Roberts Noble Foundation2510 Sam Noble Parkway, Ardmore, OK, 73401, USA
| | - Yuhong Tang
- Plant Biology Division, The Samuel Roberts Noble Foundation2510 Sam Noble Parkway, Ardmore, OK, 73401, USA
| | - Zeng-Yu Wang
- Forage Improvement Division, The Samuel Roberts Noble Foundation2510 Sam Noble Parkway, Ardmore, OK, 73401, USA
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1025
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Barna B, Fodor J, Harrach BD, Pogány M, Király Z. The Janus face of reactive oxygen species in resistance and susceptibility of plants to necrotrophic and biotrophic pathogens. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2012; 59:37-43. [PMID: 22321616 DOI: 10.1016/j.plaphy.2012.01.014] [Citation(s) in RCA: 99] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Accepted: 01/17/2012] [Indexed: 05/19/2023]
Abstract
Plant pathogens can be divided into biotrophs and necrotrophs according to their different life styles; biotrophs prefer living, while necrotrophs prefer dead cells for nutritional purposes. Therefore tissue necrosis caused by reactive oxygen species (ROS) during pathogen infection increases host susceptibility to necrotrophic, but resistance to biotrophic pathogen. Consequently, elevation of antioxidant capacity of plants enhances their tolerance to development of necroses caused by necrotrophic pathogens. Plant hormones can strongly influence induction of ROS and antioxidants, thereby influencing susceptibility or resistance of plants to pathogens. Pathogen-induced ROS themselves are considered as signaling molecules. Generally, salicylic acid (SA) signaling induces defense against biotrophic pathogens, whereas jasmonic acid (JA) against necrotrophic pathogens. Furthermore pathogens can modify plant's defense signaling network for their own benefit by changing phytohormone homeostasis. On the other hand, ROS are harmful also to the pathogens, consequently they try to defend themselves by elevating antioxidant activity and secreting ROS scavengers in the infected tissue. The Janus face nature of ROS and plant cell death on biotrophic and on necrotrophic pathogens is also supported by the experiments with BAX inhibitor-1 and the mlo mutation of Mlo gene in barley. It was found that ROS and elevated plant antioxidant activity play an important role in systemic acquired resistance (SAR) and induced systemic resistance (ISR), as well as in mycorrhiza induced abiotic and biotic stress tolerance of plants.
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Affiliation(s)
- B Barna
- Plant Protection Institute, Hungarian Academy of Sciences, P.O. Box 102, 1525 Budapest, Hungary.
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1026
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Ponce De León I, Schmelz EA, Gaggero C, Castro A, Álvarez A, Montesano M. Physcomitrella patens activates reinforcement of the cell wall, programmed cell death and accumulation of evolutionary conserved defence signals, such as salicylic acid and 12-oxo-phytodienoic acid, but not jasmonic acid, upon Botrytis cinerea infection. MOLECULAR PLANT PATHOLOGY 2012; 13:960-74. [PMID: 22551417 PMCID: PMC6638766 DOI: 10.1111/j.1364-3703.2012.00806.x] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The moss Physcomitrella patens is an evolutionarily basal model system suitable for the analysis of plant defence responses activated after pathogen assault. Upon infection with the necrotroph Botrytis cinerea, several defence mechanisms are induced in P. patens, including the fortification of the plant cell wall by the incorporation of phenolic compounds and the induced expression of related genes. Botrytis cinerea infection also activates the accumulation of reactive oxygen species and cell death with hallmarks of programmed cell death in moss tissues. Salicylic acid (SA) levels also increase after fungal infection, and treatment with SA enhances transcript accumulation of the defence gene phenylalanine ammonia-lyase (PAL) in P. patens colonies. The expression levels of the genes involved in 12-oxo-phytodienoic acid (OPDA) synthesis, including lipoxygenase (LOX) and allene oxide synthase (AOS), increase in P. patens gametophytes after pathogen assault, together with a rise in free linolenic acid and OPDA concentrations. However, jasmonic acid (JA) could not be detected in healthy or infected tissues of this plant. Our results suggest that, although conserved defence signals, such as SA and OPDA, are synthesized and are probably involved in the defence response of P. patens against B. cinerea infection, JA production appears to be missing. Interestingly, P. patens responds to OPDA and methyl jasmonate by reducing moss colony growth and rhizoid length, suggesting that jasmonate perception is present in mosses. Thus, P. patens can provide clues with regard to the evolution of different defence pathways in plants, including signalling and perception of OPDA and jasmonates in nonflowering and flowering plants.
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Affiliation(s)
- Inés Ponce De León
- Departamento de Biología Molecular, Instituto de Investigaciones Biológicas Clemente Estable, Avenida Italia 3318, CP 11600, Montevideo, Uruguay.
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1027
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Reitz MU, Bissue JK, Zocher K, Attard A, Hückelhoven R, Becker K, Imani J, Eichmann R, Schäfer P. The subcellular localization of Tubby-like proteins and participation in stress signaling and root colonization by the mutualist Piriformospora indica. PLANT PHYSIOLOGY 2012; 160:349-64. [PMID: 22751378 PMCID: PMC3498949 DOI: 10.1104/pp.112.201319] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Tubby and Tubby-like proteins (TLPs) were first discovered in mammals, where they are involved in the development and function of neuronal cells. Due to their importance as plasma membrane (PM)-tethered transcription factors or mediators of vesicle trafficking, their lack causes obesity and other disease syndromes. Phosphatidylinositol 4,5-bisphosphate binding of the carboxyl-terminal Tubby domain attaches these proteins to the PM and vesicles and is essential for function. TLPs are conserved across eukaryotic kingdoms including plants, suggesting fundamental biological functions of TLPs. Plant TLPs possess an amino-terminal F-box domain that distinguishes them from other eukaryotic TLPs. Arabidopsis (Arabidopsis thaliana) encodes 11 AtTLPs that fall into six phylogenetic clades. We identified the significance of AtTLPs for root colonization of Arabidopsis by the mutualistic fungus Piriformospora indica. Our results further indicate conserved phosphatidylinositol 4,5-bisphosphate-binding sites in the Tubby domains that are required for PM anchoring of AtTLPs. More detailed studies revealed phospholipase C-triggered release of AtTLP3 from the PM, indicating a conserved mechanism as reported for mammalian Tubby and TLP3. We further show that hydrogen peroxide stimulates the release of AtTLP3 from the PM, presumably for activating downstream events. Different from mammalian homologs, the amino-terminal part of almost all AtTLPs has nucleocytosolic and plastidial localization patterns. Thus, it is tempting to assume that TLPs translate reactive oxygen species currents into signaling not only for transcriptional regulation in the nucleus but also affect plastid-associated functions after release from the PM.
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1028
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Qi L, Yan J, Li Y, Jiang H, Sun J, Chen Q, Li H, Chu J, Yan C, Sun X, Yu Y, Li C, Li C. Arabidopsis thaliana plants differentially modulate auxin biosynthesis and transport during defense responses to the necrotrophic pathogen Alternaria brassicicola. THE NEW PHYTOLOGIST 2012; 195:872-882. [PMID: 22731664 DOI: 10.1111/j.1469-8137.2012.04208.x] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Although the role of auxin in biotrophic pathogenesis has been extensively studied, relatively little is known about its role in plant resistance to necrotrophs. Arabidopsis thaliana mutants defective in different aspects of the auxin pathway are generally more susceptible than wild-type plants to the necrotrophic pathogen Alternaria brassicicola. We show that A. brassicicola infection up-regulates auxin biosynthesis and down-regulates the auxin transport capacities of infected plants, these effects being partially dependent on JA signaling. We also show that these effects of A. brassicicola infection together lead to an enhanced auxin response in host plants. Application of IAA and MeJA together synergistically induces the expression of defense marker genes PDF1.2 (PLANT DEFENSIN 1.2) and HEL (HEVEIN-LIKE), suggesting that enhancement of JA-dependent defense signaling may be part of the auxin-mediated defense mechanism involved in resistance to necrotrophic pathogens. Our results provide molecular evidence supporting the hypothesis that JA and auxin interact positively in regulating plant resistance to necrotrophic pathogens and that activation of auxin signaling by JA may contribute to plant resistance to necrotrophic pathogens.
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Affiliation(s)
- Linlin Qi
- State Key Laboratory of Plant Genomics, National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Datun Road, Beijing 100101, China
| | - Jiao Yan
- The State Key Laboratory of Crop Biology, Agronomy College, Shandong Agricultural University, Taian 271018, China
| | - Yanan Li
- State Key Laboratory of Plant Genomics, National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Datun Road, Beijing 100101, China
| | - Hongling Jiang
- State Key Laboratory of Plant Genomics, National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Datun Road, Beijing 100101, China
| | - Jiaqiang Sun
- State Key Laboratory of Plant Genomics, National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Datun Road, Beijing 100101, China
| | - Qian Chen
- State Key Laboratory of Plant Genomics, National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Datun Road, Beijing 100101, China
| | - Haoxuan Li
- State Key Laboratory of Plant Genomics, National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Datun Road, Beijing 100101, China
- College of Agriculture, Nanjing Agricultural University, Nanjing 201195, China
| | - Jinfang Chu
- State Key Laboratory of Plant Genomics, National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Datun Road, Beijing 100101, China
| | - Cunyu Yan
- State Key Laboratory of Plant Genomics, National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Datun Road, Beijing 100101, China
| | - Xiaohong Sun
- State Key Laboratory of Plant Genomics, National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Datun Road, Beijing 100101, China
| | - Yuanjie Yu
- The State Key Laboratory of Crop Biology, Agronomy College, Shandong Agricultural University, Taian 271018, China
| | - Changbao Li
- Vegetable Research Center, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China
| | - Chuanyou Li
- State Key Laboratory of Plant Genomics, National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Datun Road, Beijing 100101, China
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1029
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Marino D, Peeters N, Rivas S. Ubiquitination during plant immune signaling. PLANT PHYSIOLOGY 2012; 160:15-27. [PMID: 22689893 PMCID: PMC3440193 DOI: 10.1104/pp.112.199281] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Accepted: 06/09/2012] [Indexed: 05/18/2023]
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1030
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Wang H, Wijeratne A, Wijeratne S, Lee S, Taylor CG, St Martin SK, McHale L, Dorrance AE. Dissection of two soybean QTL conferring partial resistance to Phytophthora sojae through sequence and gene expression analysis. BMC Genomics 2012; 13:428. [PMID: 22925529 PMCID: PMC3443417 DOI: 10.1186/1471-2164-13-428] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2012] [Accepted: 08/14/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Phytophthora sojae is the primary pathogen of soybeans that are grown on poorly drained soils. Race-specific resistance to P. sojae in soybean is gene-for-gene, although in many areas of the US and worldwide there are populations that have adapted to the most commonly deployed resistance to P. sojae ( Rps) genes. Hence, this system has received increased attention towards identifying mechanisms and molecular markers associated with partial resistance to this pathogen. Several quantitative trait loci (QTL) have been identified in the soybean cultivar 'Conrad' that contributes to the expression of partial resistance to multiple P. sojae isolates. RESULTS In this study, two of the Conrad QTL on chromosome 19 were dissected through sequence and expression analysis of genes in both resistant (Conrad) and susceptible ('Sloan') genotypes. There were 1025 single nucleotide polymorphisms (SNPs) in 87 of 153 genes sequenced from Conrad and Sloan. There were 304 SNPs in 54 genes sequenced from Conrad compared to those from both Sloan and Williams 82, of which 11 genes had SNPs unique to Conrad. Eleven of 19 genes in these regions analyzed with qRT-PCR had significant differences in fold change of transcript abundance in response to infection with P. sojae in lines with QTL haplotype from the resistant parent compared to those with the susceptible parent haplotype. From these, 8 of the 11 genes had SNPs in the upstream, untranslated region, exon, intron, and/or downstream region. These 11 candidate genes encode proteins potentially involved in signal transduction, hormone-mediated pathways, plant cell structural modification, ubiquitination, and basal resistance. CONCLUSIONS These findings may indicate a complex defense network with multiple mechanisms underlying these two soybean QTL conferring resistance to P. sojae. SNP markers derived from these candidate genes can contribute to fine mapping of QTL and marker assisted breeding for resistance to P. sojae.
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Affiliation(s)
- Hehe Wang
- The Department of Plant Pathology, The Ohio State University, Wooster, OH 44691, USA
| | - Asela Wijeratne
- Molecular and Cellular Imaging Center, OARDC, Wooster, OH 44691, USA
| | - Saranga Wijeratne
- Molecular and Cellular Imaging Center, OARDC, Wooster, OH 44691, USA
| | - Sungwoo Lee
- Department of Horticulture and Crop Science, The Ohio State University, Columbus, OH 43210, USA
| | - Christopher G Taylor
- The Department of Plant Pathology, The Ohio State University, Wooster, OH 44691, USA
| | - Steven K St Martin
- Department of Horticulture and Crop Science, The Ohio State University, Columbus, OH 43210, USA
| | - Leah McHale
- Department of Horticulture and Crop Science, The Ohio State University, Columbus, OH 43210, USA
| | - Anne E Dorrance
- The Department of Plant Pathology, The Ohio State University, Wooster, OH 44691, USA
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1031
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Fabro G, Alvarez ME. Loss of compatibility might explain resistance of the Arabidopsis thaliana accession Te-0 to Golovinomyces cichoracearum. BMC PLANT BIOLOGY 2012; 12:143. [PMID: 22883024 PMCID: PMC3546952 DOI: 10.1186/1471-2229-12-143] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2012] [Accepted: 08/03/2012] [Indexed: 05/08/2023]
Abstract
BACKGROUND The establishment of compatibility between plants and pathogens requires compliance with various conditions, such as recognition of the right host, suppression of defence mechanisms, and maintenance of an environment allowing pathogen reproduction. To date, most of the plant factors required to sustain compatibility remain unknown, with the few best characterized being those interfering with defence responses. A suitable system to study host compatibility factors is the interaction between Arabidopsis thaliana and the powdery mildew (PM) Golovinomyces cichoracearum. As an obligate biotrophic pathogen, this fungus must establish compatibility in order to perpetuate. In turn, A. thaliana displays natural variation for susceptibility to this invader, with some accessions showing full susceptibility (Col-0), and others monogenic dominant resistance (Kas-1). Interestingly, Te-0, among other accessions, displays recessive partial resistance to this PM. RESULTS In this study, we characterized the interaction of G. cichoracearum with Te-0 plants to investigate the basis of this plant resistance. We found that Te-0's incompatibility was not associated with hyper-activation of host inducible defences. Te-0 plants allowed germination of conidia and development of functional haustoria, but could not support the formation of mature conidiophores. Using a suppressive subtractive hybridization technique, we identified plant genes showing differential expression between resistant Te-0 and susceptible Col-0 plants at the fungal pre-conidiation stage. CONCLUSIONS Te-0 resistance is likely caused by loss of host compatibility and not by stimulation of inducible defences. Conidiophores formation is the main constraint for completion of fungal life cycle in Te-0 plants. The system here described allowed the identification of genes proposed as markers for susceptibility to this PM.
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Affiliation(s)
- Georgina Fabro
- Centro de Investigaciones en Química Biológica de Córdoba CIQUIBIC, UNC-CONICET, Departamento de Química Biológica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Ciudad Universitaria, Córdoba, X5000HUA, Argentina
| | - María Elena Alvarez
- Centro de Investigaciones en Química Biológica de Córdoba CIQUIBIC, UNC-CONICET, Departamento de Química Biológica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Ciudad Universitaria, Córdoba, X5000HUA, Argentina
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1032
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Garg R, Tyagi AK, Jain M. Microarray analysis reveals overlapping and specific transcriptional responses to different plant hormones in rice. PLANT SIGNALING & BEHAVIOR 2012; 7:951-6. [PMID: 22827941 PMCID: PMC3474693 DOI: 10.4161/psb.20910] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Hormones exert pleiotropic effects on plant growth and development throughout the life cycle. Many of these effects are mediated at molecular level via altering gene expression. In this study, we investigated the exogenous effect of plant hormones, including auxin, cytokinin, abscisic acid, ethylene, salicylic acid and jasmonic acid, on the transcription of rice genes at whole genome level using microarray. Our analysis identified a total of 4171 genes involved in several biological processes, whose expression was altered significantly in the presence of different hormones. Further, 28% of these genes exhibited overlapping transcriptional responses in the presence of any two hormones, indicating crosstalk among plant hormones. In addition, we identified genes showing only a particular hormone-specific response, which can be used as hormone-specific markers. The results of this study will facilitate further studies in hormone biology in rice.
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1033
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1034
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Choi HW, Hwang BK. The pepper extracellular peroxidase CaPO2 is required for salt, drought and oxidative stress tolerance as well as resistance to fungal pathogens. PLANTA 2012; 235:1369-82. [PMID: 22210598 DOI: 10.1007/s00425-011-1580-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2011] [Accepted: 12/19/2011] [Indexed: 05/03/2023]
Abstract
In plants, biotic and abiotic stresses regulate the expression and activity of various peroxidase isoforms. Capsicum annuum EXTRACELLULAR PEROXIDASE 2 (CaPO2) was previously shown to play a role in local and systemic reactive oxygen species bursts and disease resistance during bacterial pathogen infection. Here, we report CaPO2 expression patterns and functions during conditions of biotic and abiotic stress. In pepper plants, CaPO2 expression was strongly induced by abscisic acid, but not by defense-related plant hormones such as salicylic acid, ethylene and jasmonic acid. CaPO2 was also strongly induced by abiotic and biotic stress treatments, including drought, cold, high salinity and infection by the hemibiotrophic fungal pathogen Colletotrichum coccodes. Loss-of-function of CaPO2 in virus-induced gene silenced pepper plants led to increased susceptibility to salt- and osmotic-induced stress. In contrast, CaPO2 overexpression in transgenic Arabidopsis thaliana plants conferred enhanced tolerance to high salt, drought, and oxidative stress, while also enhancing resistance to infection by the necrotrophic fungal pathogen Alternaria brassicicola. Taken together, these results provide evidence for the involvement of pepper extracellular peroxidase CaPO2 in plant defense responses to various abiotic stresses and plant fungal pathogens.
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Affiliation(s)
- Hyong Woo Choi
- Laboratory of Molecular Plant Pathology, School of Life Sciences and Biotechnology, Korea University, Anam-dong, Sungbuk-ku, Seoul 136-713, Republic of Korea
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1035
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Lahrmann U, Zuccaro A. Opprimo ergo sum--evasion and suppression in the root endophytic fungus Piriformospora indica. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2012; 25:727-37. [PMID: 22352718 DOI: 10.1094/mpmi-11-11-0291] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The genetically tractable endophytic fungus Piriformospora indica is able to colonize the root cortex of a great variety of different plant species with beneficial effects to its hosts, and it represents a suitable model system to study symbiotic interactions. Recent cytological studies in barley and Arabidopsis showed that, upon penetration of the root, P. indica establishes a biotrophic interaction during which fungal cells are encased by the host plasma membrane. Large-scale transcriptional analyses of fungal and plant responses have shown that perturbance of plant hormone homeostasis and secretion of fungal lectins and other small proteins (effectors) may be involved in the evasion and suppression of host defenses at these early colonization steps. At later stages, P. indica is found more often in moribund host cells where it secretes a large variety of hydrolytic enzymes that degrade proteins. This strategy of colonizing plants is reminiscent of that of hemibiotrophic fungi, although a defined shift to necrotrophy with massive host cell death is missing. Instead, the association with the plant root leads to beneficial effects for the host such as growth promotion, increased resistance to root as well as leaf pathogens, and increased tolerance to abiotic stresses. This review describes current advances in understanding the components of the P. indica endophytic lifestyle from molecular and genomic analyses.
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Affiliation(s)
- Urs Lahrmann
- Max Planck Institute for Terrestrial Microbiology - Organismic Interations, Marburg, Germany
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1036
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Hemetsberger C, Herrberger C, Zechmann B, Hillmer M, Doehlemann G. The Ustilago maydis effector Pep1 suppresses plant immunity by inhibition of host peroxidase activity. PLoS Pathog 2012; 8:e1002684. [PMID: 22589719 PMCID: PMC3349748 DOI: 10.1371/journal.ppat.1002684] [Citation(s) in RCA: 251] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2011] [Accepted: 03/22/2012] [Indexed: 01/25/2023] Open
Abstract
The corn smut Ustilago maydis establishes a biotrophic interaction with its host plant maize. This interaction requires efficient suppression of plant immune responses, which is attributed to secreted effector proteins. Previously we identified Pep1 (Protein essential during penetration-1) as a secreted effector with an essential role for U. maydis virulence. pep1 deletion mutants induce strong defense responses leading to an early block in pathogenic development of the fungus. Using cytological and functional assays we show that Pep1 functions as an inhibitor of plant peroxidases. At sites of Δpep1 mutant penetrations, H₂O₂ strongly accumulated in the cell walls, coinciding with a transcriptional induction of the secreted maize peroxidase POX12. Pep1 protein effectively inhibited the peroxidase driven oxidative burst and thereby suppresses the early immune responses of maize. Moreover, Pep1 directly inhibits peroxidases in vitro in a concentration-dependent manner. Using fluorescence complementation assays, we observed a direct interaction of Pep1 and the maize peroxidase POX12 in vivo. Functional relevance of this interaction was demonstrated by partial complementation of the Δpep1 mutant defect by virus induced gene silencing of maize POX12. We conclude that Pep1 acts as a potent suppressor of early plant defenses by inhibition of peroxidase activity. Thus, it represents a novel strategy for establishing a biotrophic interaction.
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Affiliation(s)
| | | | - Bernd Zechmann
- Institute of Plant Sciences, Karl-Franzens University of Graz, Graz, Austria
| | - Morten Hillmer
- Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
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1037
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Eschen-Lippold L, Lübken T, Smolka U, Rosahl S. Characterization of potato plants with reduced StSYR1 expression. PLANT SIGNALING & BEHAVIOR 2012; 7:559-562. [PMID: 22516814 PMCID: PMC3419019 DOI: 10.4161/psb.19866] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Vesicle fusion processes in plants are important for both development and stress responses. Transgenic potato plants with reduced expression of SYNTAXIN-RELATED1 (StSYR1), a gene encoding the potato homolog of Arabidopsis PENETRATION1 (AtPEN1), display spontaneous necrosis and chlorosis at later stages of development. In accordance with this developmental defect, tuber number, weight and overall yield are significantly reduced in StSYR1-RNAi lines. Enhanced resistance of StSYR1-RNAi plants to Phytophthora infestans, the causal agent of late blight disease of potato, correlates with enhanced levels of salicylic acid, whereas levels of 12-oxophytodienoic acid and jasmonic acid are unaltered. Cultured cells of StSYR1-RNAi lines secrete at least two compounds which are not detectable in the supernatant of control cells, suggesting an involvement of StSYR1 in secretion processes to the apoplast.
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1038
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Erb M, Meldau S, Howe GA. Role of phytohormones in insect-specific plant reactions. TRENDS IN PLANT SCIENCE 2012; 17:250-9. [PMID: 22305233 PMCID: PMC3346861 DOI: 10.1016/j.tplants.2012.01.003] [Citation(s) in RCA: 506] [Impact Index Per Article: 42.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Revised: 12/20/2011] [Accepted: 01/05/2012] [Indexed: 05/17/2023]
Abstract
The capacity to perceive and respond is integral to biological immune systems, but to what extent can plants specifically recognize and respond to insects? Recent findings suggest that plants possess surveillance systems that are able to detect general patterns of cellular damage as well as highly specific herbivore-associated cues. The jasmonate (JA) pathway has emerged as the major signaling cassette that integrates information perceived at the plant-insect interface into broad-spectrum defense responses. Specificity can be achieved via JA-independent processes and spatio-temporal changes of JA-modulating hormones, including ethylene (ET), salicylic acid (SA), abscisic acid (ABA), auxin, cytokinins (CK), brassinosteroids (BR) and gibberellins (GB). The identification of receptors and ligands and an integrative view of hormone-mediated response systems are crucial to understand specificity in plant immunity to herbivores.
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Affiliation(s)
- Matthias Erb
- Root-Herbivore Interactions Group, Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, 07745 Jena, Germany.
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1039
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Thaler JS, Humphrey PT, Whiteman NK. Evolution of jasmonate and salicylate signal crosstalk. TRENDS IN PLANT SCIENCE 2012; 17:260-70. [PMID: 22498450 DOI: 10.1016/j.tplants.2012.02.010] [Citation(s) in RCA: 670] [Impact Index Per Article: 55.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2011] [Revised: 02/25/2012] [Accepted: 02/28/2012] [Indexed: 05/18/2023]
Abstract
The evolution of land plants approximately 470 million years ago created a new adaptive zone for natural enemies (attackers) of plants. In response to attack, plants evolved highly effective, inducible defense systems. Two plant hormones modulating inducible defenses are salicylic acid (SA) and jasmonic acid (JA). Current thinking is that SA induces resistance against biotrophic pathogens and some phloem feeding insects and JA induces resistance against necrotrophic pathogens, some phloem feeding insects and chewing herbivores. Signaling crosstalk between SA and JA commonly manifests as a reciprocal antagonism and may be adaptive, but this remains speculative. We examine evidence for and against adaptive explanations for antagonistic crosstalk, trace its phylogenetic origins and provide a hypothesis-testing framework for future research on the adaptive significance of SA-JA crosstalk.
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1040
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Berr A, Ménard R, Heitz T, Shen WH. Chromatin modification and remodelling: a regulatory landscape for the control of Arabidopsis defence responses upon pathogen attack. Cell Microbiol 2012; 14:829-39. [DOI: 10.1111/j.1462-5822.2012.01785.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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1041
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Maldonado-Calderón MT, Sepúlveda-García E, Rocha-Sosa M. Characterization of novel F-box proteins in plants induced by biotic and abiotic stress. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2012; 185-186:208-17. [PMID: 22325883 DOI: 10.1016/j.plantsci.2011.10.013] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Revised: 09/13/2011] [Accepted: 10/19/2011] [Indexed: 05/08/2023]
Abstract
Plants protect against pathogen infections by a combination of constitutive and induced strategies. The induction of plant defense involves the recognition of compounds derived from the pathogen or the plant itself, called elicitors. Looking for new genes involved in plant defense responses, we isolated a cDNA clone corresponding to an elicitor-induced mRNA from Phaseolus vulgaris cell suspension cultures. This clone, PvFBS1, encodes a protein with an F-box, therefore a putative component of an SCF ubiquitin ligase complex. PvFBS1 mRNA accumulates in leaves of whole plants in response to wounding or osmotic stress, as well as, following the application of methyl jasmonate (MeJA). salicylic acid (SA) or abscisic acid (ABA). Several sequences related to PvFBS1 were found in the GenBank. In Arabidopsis thaliana there are 4 genomic sequences coding for proteins with similarity to PvFBS1. One of them, AtFBS1, displays a pattern of induction analogous to the one observed for PvFBS1. A yeast two-hybrid assay proved that AtFBS1 was able to interact with ASK1, the component of the SCF complex that binds the F-box. A deletion of the F-box in AtFBS1 abolishes the ability of this protein to interact with ASK1. This demonstrates the functionality of the F-box contained in AtFBS1. Gene fusions to the GUS reporter gene revealed a complex regulation for AtFBS1 expression.
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Affiliation(s)
- María Teresa Maldonado-Calderón
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo Postal 510-3, Cuernavaca, Mor. 62250 Mexico.
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1042
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De Vleesschauwer D, Van Buyten E, Satoh K, Balidion J, Mauleon R, Choi IR, Vera-Cruz C, Kikuchi S, Höfte M. Brassinosteroids antagonize gibberellin- and salicylate-mediated root immunity in rice. PLANT PHYSIOLOGY 2012; 158:1833-46. [PMID: 22353574 PMCID: PMC3320189 DOI: 10.1104/pp.112.193672] [Citation(s) in RCA: 129] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Accepted: 02/15/2012] [Indexed: 05/18/2023]
Abstract
Brassinosteroids (BRs) are a unique class of plant steroid hormones that orchestrate myriad growth and developmental processes. Although BRs have long been known to protect plants from a suite of biotic and abiotic stresses, our understanding of the underlying molecular mechanisms is still rudimentary. Aiming to further decipher the molecular logic of BR-modulated immunity, we have examined the dynamics and impact of BRs during infection of rice (Oryza sativa) with the root oomycete Pythium graminicola. Challenging the prevailing view that BRs positively regulate plant innate immunity, we show that P. graminicola exploits BRs as virulence factors and hijacks the rice BR machinery to inflict disease. Moreover, we demonstrate that this immune-suppressive effect of BRs is due, at least in part, to negative cross talk with salicylic acid (SA) and gibberellic acid (GA) pathways. BR-mediated suppression of SA defenses occurred downstream of SA biosynthesis, but upstream of the master defense regulators NONEXPRESSOR OF PATHOGENESIS-RELATED GENES1 and OsWRKY45. In contrast, BR alleviated GA-directed immune responses by interfering at multiple levels with GA metabolism, resulting in indirect stabilization of the DELLA protein and central GA repressor SLENDER RICE1 (SLR1). Collectively, these data favor a model whereby P. graminicola coopts the plant BR pathway as a decoy to antagonize effectual SA- and GA-mediated defenses. Our results highlight the importance of BRs in modulating plant immunity and uncover pathogen-mediated manipulation of plant steroid homeostasis as a core virulence strategy.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Monica Höfte
- Laboratory of Phytopathology, Ghent University, B–9000 Ghent, Belgium (D.D.V., E.V.B., M.H.); Plant Genome Research Unit, Agrogenomics Research Center, National Institute of Agrobiological Sciences, Tsukuba 305–8602, Ibaraki, Japan (K.S., S.K.); Plant Breeding, Genetics, and Biotechnology Division (J.B., I.-R.C., C.V.-C.) and Crop Research Informatics Laboratory (R.M.), International Rice Research Institute, 1099 Metro Manila, Philippines
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1043
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Rayson S, Arciga-Reyes L, Wootton L, De Torres Zabala M, Truman W, Graham N, Grant M, Davies B. A role for nonsense-mediated mRNA decay in plants: pathogen responses are induced in Arabidopsis thaliana NMD mutants. PLoS One 2012; 7:e31917. [PMID: 22384098 PMCID: PMC3284524 DOI: 10.1371/journal.pone.0031917] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2011] [Accepted: 01/15/2012] [Indexed: 11/19/2022] Open
Abstract
Nonsense-mediated mRNA decay (NMD) is a conserved mechanism that targets aberrant mRNAs for destruction. NMD has also been found to regulate the expression of large numbers of genes in diverse organisms, although the biological role for this is unclear and few evolutionarily conserved targets have been identified. Expression analyses of three Arabidopsis thaliana lines deficient in NMD reveal that the vast majority of NMD-targeted transcripts are associated with response to pathogens. Congruently, NMD mutants, in which these transcripts are elevated, confer partial resistance to Pseudomonas syringae. These findings suggest a biological rationale for the regulation of gene expression by NMD in plants and suggest that manipulation of NMD could offer a new approach for crop protection. Amongst the few non-pathogen responsive NMD-targeted genes, one potential NMD targeted signal, the evolutionarily conserved upstream open reading frame (CuORF), was found to be hugely over-represented, raising the possibility that this feature could be used to target specific physiological mRNAs for control by NMD.
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Affiliation(s)
- Samantha Rayson
- Centre for Plant Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
| | - Luis Arciga-Reyes
- Centre for Plant Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
| | - Lucie Wootton
- Centre for Plant Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
| | | | - William Truman
- School of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Neil Graham
- Nottingham Arabidopsis Stock Centre, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, United Kingdom
| | - Murray Grant
- School of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Brendan Davies
- Centre for Plant Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
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1044
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Pseudomonas syringae type III effector repertoires: last words in endless arguments. Trends Microbiol 2012; 20:199-208. [PMID: 22341410 DOI: 10.1016/j.tim.2012.01.003] [Citation(s) in RCA: 157] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Revised: 12/20/2011] [Accepted: 01/04/2012] [Indexed: 01/10/2023]
Abstract
Many plant pathogens subvert host immunity by injecting compositionally diverse but functionally similar repertoires of cytoplasmic effector proteins. The bacterial pathogen Pseudomonas syringae is a model for exploring the functional structure of such repertoires. The pangenome of P. syringae encodes 57 families of effectors injected by the type III secretion system. Distribution of effector genes among phylogenetically diverse strains reveals a small set of core effectors targeting antimicrobial vesicle trafficking and a much larger set of variable effectors targeting kinase-based recognition processes. Complete disassembly of the 28-effector repertoire of a model strain and reassembly of a minimal functional repertoire reveals the importance of simultaneously attacking both processes. These observations, coupled with growing knowledge of effector targets in plants, support a model for coevolving molecular dialogs between effector repertoires and plant immune systems that emphasizes mutually-driven expansion of the components governing recognition.
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1045
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Kangasjärvi S, Neukermans J, Li S, Aro EM, Noctor G. Photosynthesis, photorespiration, and light signalling in defence responses. JOURNAL OF EXPERIMENTAL BOTANY 2012; 63:1619-36. [PMID: 22282535 DOI: 10.1093/jxb/err402] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Visible light is the basic energetic driver of plant biomass production through photosynthesis. The constantly fluctuating availability of light and other environmental factors means that the photosynthetic apparatus must be able to operate in a dynamic fashion appropriate to the prevailing conditions. Dynamic regulation is achieved through an array of homeostatic control mechanisms that both respond to and influence cellular energy and reductant status. In addition, light availability and quality are continuously monitored by plants through photoreceptors. Outside the laboratory growth room, it is within the context of complex changes in energy and signalling status that plants must regulate pathways to deal with biotic challenges, and this can be influenced by changes in the highly energetic photosynthetic pathways and in the turnover of the photosynthetic machinery. Because of this, defence responses are neither simple nor easily predictable, but rather conditioned by the nutritional and signalling status of the plant cell. This review discusses recent data and emerging concepts of how recognized defence pathways interact with and are influenced by light-dependent processes. Particular emphasis is placed on the potential roles of the chloroplast, photorespiration, and photoreceptor-associated pathways in regulating the outcome of interactions between plants and pathogenic organisms.
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Affiliation(s)
- Saijaliisa Kangasjärvi
- Department of Biochemistry and Food Chemistry, University of Turku, FI-20014 Turku, Finland.
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1046
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Analytical methods for tracing plant hormones. Anal Bioanal Chem 2012; 403:55-74. [PMID: 22215246 DOI: 10.1007/s00216-011-5623-x] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2011] [Revised: 11/27/2011] [Accepted: 11/28/2011] [Indexed: 12/22/2022]
Abstract
Plant hormones play important roles in regulating numerous aspects of plant growth, development, and response to stress. In the past decade, more analytical methods for the accurate identification and quantitative determination of trace plant hormones have been developed to better our understanding of the molecular mechanisms of plant hormones. As sample preparation is often the bottleneck in analysis of plant hormones in biological samples, this review firstly discusses sample preparation techniques after a brief introduction to the classes, roles, and methods used in the analysis of plant hormones. The analytical methods, especially chromatographic techniques and immuno-based methods, are reviewed in detail, and their corresponding advantages, limitations, applications, and prospects are also discussed. This review mainly covers reports published from 2000 to the present on methods for the analysis of plant hormones.
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1047
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Burch-Smith TM, Zambryski PC. Plasmodesmata paradigm shift: regulation from without versus within. ANNUAL REVIEW OF PLANT BIOLOGY 2012; 63:239-60. [PMID: 22136566 DOI: 10.1146/annurev-arplant-042811-105453] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Plant cells are surrounded by cellulosic cell walls, creating a potential challenge to resource sharing and information exchange between individual cells. To overcome this, plants have evolved channels called plasmodesmata that provide cytoplasmic continuity between each cell and its immediate neighbors. We first review plasmodesmata basics-their architecture, their origin, the types of cargo they transport, and their molecular components. The bulk of this review discusses the regulation of plasmodesmata formation and function. Historically, plasmodesmata research has focused intensely on uncovering regulatory or structural proteins that reside within or immediately adjacent to plasmodesmata. Recent findings, however, underscore that plasmodesmata are exquisitely sensitive to signals far removed from the plasmodesmal channel itself. Signals originating from molecules and pathways that regulate cellular homeostasis-such as reactive oxygen species, organelle-organelle signaling, and organelle-nucleus signaling-lead to astonishing alterations in gene expression that affect plasmodesmata formation and function.
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Affiliation(s)
- Tessa M Burch-Smith
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
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1048
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Kazan K, Manners JM. JAZ repressors and the orchestration of phytohormone crosstalk. TRENDS IN PLANT SCIENCE 2012; 17:22-31. [PMID: 22112386 DOI: 10.1016/j.tplants.2011.10.006] [Citation(s) in RCA: 229] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Revised: 10/24/2011] [Accepted: 10/26/2011] [Indexed: 05/18/2023]
Abstract
The JAZ (JASMONATE-ZIM DOMAIN) family proteins act as jasmonate (JA) co-receptors and transcriptional repressors in JA signalling in Arabidopsis (Arabidopsis thaliana). Recently, identification of JAZ-interacting proteins regulating different aspects of the JA pathway has shown that JAZ repressors have overlapping, but finely separated functions in JA signalling. In addition, new insights into suppression mechanisms employed by JAZ proteins have been uncovered. Here we first briefly review these recent findings and then highlight newly identified roles for JAZ proteins in orchestrating the crosstalk between JA and other hormone signalling pathways such as ethylene, gibberellin, salicylic acid and auxin. The emerging roles that JAZ proteins play in the regulation of diverse phytohormone signalling interactions illustrate the functional versatility of this protein family.
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Affiliation(s)
- Kemal Kazan
- Commonwealth Scientific and Industrial Research Organization, Plant Industry, Queensland Bioscience Precinct, St Lucia, Queensland 4067, Australia.
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1049
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Friedel S, Usadel B, von Wirén N, Sreenivasulu N. Reverse engineering: a key component of systems biology to unravel global abiotic stress cross-talk. FRONTIERS IN PLANT SCIENCE 2012; 3:294. [PMID: 23293646 PMCID: PMC3533172 DOI: 10.3389/fpls.2012.00294] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Accepted: 12/10/2012] [Indexed: 05/18/2023]
Abstract
Understanding the global abiotic stress response is an important stepping stone for the development of universal stress tolerance in plants in the era of climate change. Although co-occurrence of several stress factors (abiotic and biotic) in nature is found to be frequent, current attempts are poor to understand the complex physiological processes impacting plant growth under combinatory factors. In this review article, we discuss the recent advances of reverse engineering approaches that led to seminal discoveries of key candidate regulatory genes involved in cross-talk of abiotic stress responses and summarized the available tools of reverse engineering and its relevant application. Among the universally induced regulators involved in various abiotic stress responses, we highlight the importance of (i) abscisic acid (ABA) and jasmonic acid (JA) hormonal cross-talks and (ii) the central role of WRKY transcription factors (TF), potentially mediating both abiotic and biotic stress responses. Such interactome networks help not only to derive hypotheses but also play a vital role in identifying key regulatory targets and interconnected hormonal responses. To explore the full potential of gene network inference in the area of abiotic stress tolerance, we need to validate hypotheses by implementing time-dependent gene expression data from genetically engineered plants with modulated expression of target genes. We further propose to combine information on gene-by-gene interactions with data from physical interaction platforms such as protein-protein or TF-gene networks.
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Affiliation(s)
- Swetlana Friedel
- Leibniz Institute of Plant Genetics and Crop Plant ResearchGatersleben, Germany
| | - Björn Usadel
- RWTH Aachen UniversityAachen, Germany
- IBG-2: Plant Sciences, Institute of Bio- and Geosciences, Forschungszentrum JülichJülich, Germany
| | - Nicolaus von Wirén
- Leibniz Institute of Plant Genetics and Crop Plant ResearchGatersleben, Germany
| | - Nese Sreenivasulu
- Leibniz Institute of Plant Genetics and Crop Plant ResearchGatersleben, Germany
- *Correspondence: Nese Sreenivasulu, Leibniz Institute of Plant Genetics and Crop Plant Research, D-06466 Gatersleben, Germany. e-mail:
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1050
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Schwessinger B, Ronald PC. Plant innate immunity: perception of conserved microbial signatures. ANNUAL REVIEW OF PLANT BIOLOGY 2012; 63:451-82. [PMID: 22404464 DOI: 10.1146/annurev-arplant-042811-105518] [Citation(s) in RCA: 220] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Plants and animals sense conserved microbial signatures through receptors localized to the plasma membrane and cytoplasm. These receptors typically carry or associate with non-arginine-aspartate (non-RD) kinases that initiate complex signaling networks cumulating in robust defense responses. In plants, coregulatory receptor kinases have been identified that not only are critical for the innate immune response but also serve an essential function in other regulatory signaling pathways.
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