1
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Liang H, Lopez IJ, Sánchez-Hidalgo M, Genilloud O, van der Donk WA. Mechanistic Studies on Dehydration in Class V Lanthipeptides. ACS Chem Biol 2022; 17:2519-2527. [PMID: 36044589 PMCID: PMC9486802 DOI: 10.1021/acschembio.2c00458] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Lanthipeptides are ribosomally synthesized and post-translationally modified peptides characterized by lanthionine (Lan) and/or methyllanthionine (MeLan) residues. Four classes of enzymes have been identified to install these structures in a substrate peptide. Recently, a novel class of lanthipeptides was discovered that lack genes for known class I-IV lanthionine synthases in their biosynthetic gene cluster (BGC). In this study, the dehydration of Ser/Thr during the biosynthesis of the class V lanthipeptide cacaoidin was reconstituted in vitro. The aminoglycoside phosphotransferase-like enzyme CaoK iteratively phosphorylates Ser/Thr residues on the precursor peptide CaoA, followed by phosphate elimination catalyzed by the HopA1 effector-like protein CaoY to achieve eight successive dehydrations. CaoY shows sequence similarity to the OspF family proteins and the lyase domains of class III/IV lanthionine synthetases, and mutagenesis studies identified residues that are critical for catalysis. An AlphaFold prediction of the structure of the dehydration enzyme complex engaged with its substrate suggests the importance of hydrophobic interactions between the CaoA leader peptide and CaoK in enzyme-substrate recognition. This model is supported by site-directed mutagenesis studies.
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Affiliation(s)
- Haoqian Liang
- Department
of Biochemistry, University of Illinois
at Urbana—Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
| | - Isaiah J. Lopez
- Department
of Biochemistry, University of Illinois
at Urbana—Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
| | - Marina Sánchez-Hidalgo
- Fundación
MEDINA Centro de Excelencia en Investigación de Medicamentos
Innovadores en Andalucía, Avenida del Conocimiento, 34 Parque Tecnológico
de Ciencias de la Salud, Armilla, 18016 Granada, Spain
| | - Olga Genilloud
- Fundación
MEDINA Centro de Excelencia en Investigación de Medicamentos
Innovadores en Andalucía, Avenida del Conocimiento, 34 Parque Tecnológico
de Ciencias de la Salud, Armilla, 18016 Granada, Spain
| | - Wilfred A. van der Donk
- Department
of Biochemistry, University of Illinois
at Urbana—Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States,Department
of Chemistry and Howard Hughes Medical Institute, University of Illinois at Urbana—Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States,
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2
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Brauer EK, Ahsan N, Popescu GV, Thelen JJ, Popescu SC. Back From the Dead: The Atypical Kinase Activity of a Pseudokinase Regulator of Cation Fluxes During Inducible Immunity. FRONTIERS IN PLANT SCIENCE 2022; 13:931324. [PMID: 36035673 PMCID: PMC9403797 DOI: 10.3389/fpls.2022.931324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 05/27/2022] [Indexed: 06/15/2023]
Abstract
Pseudokinases are thought to lack phosphotransfer activity due to altered canonical catalytic residues within their kinase domain. However, a subset of pseudokinases maintain activity through atypical phosphotransfer mechanisms. The Arabidopsis ILK1 is a pseudokinase from the Raf-like MAP3K family and is the only known plant pseudokinase with confirmed protein kinase activity. ILK1 activity promotes disease resistance and molecular pattern-induced root growth inhibition through its stabilization of the HAK5 potassium transporter with the calmodulin-like protein CML9. ILK1 also has a kinase-independent function in salt stress suggesting that it interacts with additional proteins. We determined that members of the ILK subfamily are the sole pseudokinases within the Raf-like MAP3K family and identified 179 novel putative ILK1 protein interactors. We also identified 70 novel peptide targets for ILK1, the majority of which were phosphorylated in the presence of Mn2+ instead of Mg2+ in line with modifications in ILK1's DFG cofactor binding domain. Overall, the ILK1-targeted or interacting proteins included diverse protein types including transporters (HAK5, STP1), protein kinases (MEKK1, MEKK3), and a cytokinin receptor (AHK2). The expression of 31 genes encoding putative ILK1-interacting or phosphorylated proteins, including AHK2, were altered in the root and shoot in response to molecular patterns suggesting a role for these genes in immunity. We describe a potential role for ILK1 interactors in the context of cation-dependent immune signaling, highlighting the importance of K+ in MAMP responses. This work further supports the notion that ILK1 is an atypical kinase with an unusual cofactor dependence that may interact with multiple proteins in the cell.
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Affiliation(s)
- Elizabeth K. Brauer
- Boyce Thompson Institute for Plant Research, Ithaca, NY, United States
- Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, NY, United States
| | - Nagib Ahsan
- Department of Biochemistry, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
| | - George V. Popescu
- Boyce Thompson Institute for Plant Research, Ithaca, NY, United States
| | - Jay J. Thelen
- Department of Biochemistry, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
| | - Sorina C. Popescu
- Boyce Thompson Institute for Plant Research, Ithaca, NY, United States
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3
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Xiong H, Ma H, Zhao H, Yang L, Hu B, Wang J, Shi X, Zhang Y, Rennenberg H. Integrated physiological, proteome and gene expression analyses provide new insights into nitrogen remobilization in citrus trees. TREE PHYSIOLOGY 2022; 42:1628-1645. [PMID: 35225347 DOI: 10.1093/treephys/tpac024] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 02/22/2022] [Indexed: 06/14/2023]
Abstract
Nitrogen (N) remobilization is an important physiological process that supports the growth and development of trees. However, in evergreen broad-leaved tree species, such as citrus, the mechanisms of N remobilization are not completely understood. Therefore, we quantified the potential of N remobilization from senescing leaves of spring shoots to mature leaves of autumn shoots of citrus trees under different soil N availabilities and further explored the underlying N metabolism characteristics by physiological, proteome and gene expression analyses. Citrus exposed to low N had an approximately 38% N remobilization efficiency (NRE), whereas citrus exposed to high N had an NRE efficiency of only 4.8%. Integrated physiological, proteomic and gene expression analyses showed that photosynthesis, N and carbohydrate metabolism interact with N remobilization. The improvement of N metabolism and photosynthesis, the accumulation of proline and arginine, and delayed degradation of storage protein in senescing leaves are the result of sufficient N supply and low N remobilization. Proteome further showed that energy generation proteins and glutamate synthase were hub proteins affecting N remobilization. In addition, N requirement of mature leaves is likely met by soil supply at high N nutrition, thereby resulting in low N remobilization. These results provide insight into N remobilization mechanisms of citrus that are of significance for N fertilizer management in orchards.
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Affiliation(s)
- Huaye Xiong
- Center of Molecular Ecophysiology (CMEP), College of Resources and Environment, Southwest University, Chongqing 400716, China
| | - Haotian Ma
- Health Science Center, Xi' an Jiaotong University, Xi'an 710061, China
| | - Huanyu Zhao
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing 400716, China
| | - Linsheng Yang
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing 400716, China
| | - Bin Hu
- Center of Molecular Ecophysiology (CMEP), College of Resources and Environment, Southwest University, Chongqing 400716, China
| | - Jie Wang
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing 400716, China
| | - Xiaojun Shi
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing 400716, China
| | - Yueqiang Zhang
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing 400716, China
| | - Heinz Rennenberg
- Center of Molecular Ecophysiology (CMEP), College of Resources and Environment, Southwest University, Chongqing 400716, China
- Chair of Tree Physiology, Institute of Forest Sciences, Albert-Ludwigs-Universität Freiburg Georges-Köhler-Allee 53/54, 79110 Freiburg, Germany
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4
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Basu S, Huynh L, Zhang S, Rabara R, Nguyen H, Velásquez Guzmán J, Hao G, Miles G, Shi Q, Stover E, Gupta G. Two Liberibacter Proteins Combine to Suppress Critical Innate Immune Defenses in Citrus. FRONTIERS IN PLANT SCIENCE 2022; 13:869178. [PMID: 35586217 PMCID: PMC9108871 DOI: 10.3389/fpls.2022.869178] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 04/04/2022] [Indexed: 06/15/2023]
Abstract
We adopted a systems-based approach to determine the role of two Candidatus Liberibacter asiaticus (CLas) proteins, LasP 235 and Effector 3, in Huanglongbing (HLB) pathogenesis. While a published work suggests the involvement of these CLas proteins HLB pathogenesis, the exact structure-based mechanism of their action has not been elucidated. We conducted the following experiments to determine the structure-based mechanisms of action. First, we immunoprecipitated the interacting citrus protein partners of LasP 235 and Effector 3 from the healthy and CLas-infected Hamlin extracts and identified them by Liquid Chromatography with tandem mass spectrometry (LC-MS/MS). Second, we performed a split green fluorescent protein (GFP) assay in tobacco to validate that the interactions observed in vitro are also retained in planta. The notable in planta citrus targets of LasP 235 and Effector 3 include citrus innate immune proteins. Third, in vitro and in planta studies were performed to show that LasP 235 and Effector 3 interact with and inhibit the functions of multiple citrus proteins belonging to the innate immune pathways. These inhibitory interactions led to a high level of reactive oxygen species, blocking of bactericidal lipid transfer protein (LTP), and induction of premature programed cell death (PCD), all of which are beneficial to CLas lifecycle and HLB pathogenesis. Finally, we performed molecular dynamics simulations to visualize the interactions of LasP 235 and Effector 3, respectively, with LTP and Kunitz protease inhibitor. This led to the design of an LTP mimic, which sequestered and blocked LasP 235 and rescued the bactericidal activity of LTP thereby proving that LasP 235 , indeed, participates in HLB pathogenesis.
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Affiliation(s)
- Supratim Basu
- Biolab, New Mexico Consortium, Los Alamos, NM, United States
| | - Loan Huynh
- Biolab, New Mexico Consortium, Los Alamos, NM, United States
| | - Shujian Zhang
- Biolab, New Mexico Consortium, Los Alamos, NM, United States
| | - Roel Rabara
- Biolab, New Mexico Consortium, Los Alamos, NM, United States
| | - Hau Nguyen
- Biolab, New Mexico Consortium, Los Alamos, NM, United States
| | | | - Guixia Hao
- Horticulture and Breeding, U. S. Horticultural Research Laboratory, Fort Pierce, FL, United States
| | - Godfrey Miles
- Horticulture and Breeding, U. S. Horticultural Research Laboratory, Fort Pierce, FL, United States
| | - Qingchun Shi
- Horticulture and Breeding, U. S. Horticultural Research Laboratory, Fort Pierce, FL, United States
| | - Ed Stover
- Horticulture and Breeding, U. S. Horticultural Research Laboratory, Fort Pierce, FL, United States
| | - Goutam Gupta
- Biolab, New Mexico Consortium, Los Alamos, NM, United States
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5
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Delplace F, Huard-Chauveau C, Berthomé R, Roby D. Network organization of the plant immune system: from pathogen perception to robust defense induction. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 109:447-470. [PMID: 34399442 DOI: 10.1111/tpj.15462] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 07/29/2021] [Accepted: 08/10/2021] [Indexed: 06/13/2023]
Abstract
The plant immune system has been explored essentially through the study of qualitative resistance, a simple form of immunity, and from a reductionist point of view. The recent identification of genes conferring quantitative disease resistance revealed a large array of functions, suggesting more complex mechanisms. In addition, thanks to the advent of high-throughput analyses and system approaches, our view of the immune system has become more integrative, revealing that plant immunity should rather be seen as a distributed and highly connected molecular network including diverse functions to optimize expression of plant defenses to pathogens. Here, we review the recent progress made to understand the network complexity of regulatory pathways leading to plant immunity, from pathogen perception, through signaling pathways and finally to immune responses. We also analyze the topological organization of these networks and their emergent properties, crucial to predict novel immune functions and test them experimentally. Finally, we report how these networks might be regulated by environmental clues. Although system approaches remain extremely scarce in this area of research, a growing body of evidence indicates that the plant response to combined biotic and abiotic stresses cannot be inferred from responses to individual stresses. A view of possible research avenues in this nascent biology domain is finally proposed.
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Affiliation(s)
- Florent Delplace
- Laboratoire des Interactions Plantes-Microbes-Environnement, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement, INRAE, CNRS, Université de Toulouse, Castanet-Tolosan, 31326, France
| | - Carine Huard-Chauveau
- Laboratoire des Interactions Plantes-Microbes-Environnement, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement, INRAE, CNRS, Université de Toulouse, Castanet-Tolosan, 31326, France
| | - Richard Berthomé
- Laboratoire des Interactions Plantes-Microbes-Environnement, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement, INRAE, CNRS, Université de Toulouse, Castanet-Tolosan, 31326, France
| | - Dominique Roby
- Laboratoire des Interactions Plantes-Microbes-Environnement, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement, INRAE, CNRS, Université de Toulouse, Castanet-Tolosan, 31326, France
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6
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Jeleńska J, Lee J, Manning AJ, Wolfgeher DJ, Ahn Y, Walters-Marrah G, Lopez IE, Garcia L, McClerklin SA, Michelmore RW, Kron SJ, Greenberg JT. Pseudomonas syringae effector HopZ3 suppresses the bacterial AvrPto1-tomato PTO immune complex via acetylation. PLoS Pathog 2021; 17:e1010017. [PMID: 34724007 PMCID: PMC8584673 DOI: 10.1371/journal.ppat.1010017] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 11/11/2021] [Accepted: 10/07/2021] [Indexed: 11/23/2022] Open
Abstract
The plant pathogen Pseudomonas syringae secretes multiple effectors that modulate plant defenses. Some effectors trigger defenses due to specific recognition by plant immune complexes, whereas others can suppress the resulting immune responses. The HopZ3 effector of P. syringae pv. syringae B728a (PsyB728a) is an acetyltransferase that modifies not only components of plant immune complexes, but also the Psy effectors that activate these complexes. In Arabidopsis, HopZ3 acetylates the host RPM1 complex and the Psy effectors AvrRpm1 and AvrB3. This study focuses on the role of HopZ3 during tomato infection. In Psy-resistant tomato, the main immune complex includes PRF and PTO, a RIPK-family kinase that recognizes the AvrPto effector. HopZ3 acts as a virulence factor on tomato by suppressing AvrPto1Psy-triggered immunity. HopZ3 acetylates AvrPto1Psy and the host proteins PTO, SlRIPK and SlRIN4s. Biochemical reconstruction and site-directed mutagenesis experiments suggest that acetylation acts in multiple ways to suppress immune signaling in tomato. First, acetylation disrupts the critical AvrPto1Psy-PTO interaction needed to initiate the immune response. Unmodified residues at the binding interface of both proteins and at other residues needed for binding are acetylated. Second, acetylation occurs at residues important for AvrPto1Psy function but not for binding to PTO. Finally, acetylation reduces specific phosphorylations needed for promoting the immune-inducing activity of HopZ3’s targets such as AvrPto1Psy and PTO. In some cases, acetylation competes with phosphorylation. HopZ3-mediated acetylation suppresses the kinase activity of SlRIPK and the phosphorylation of its SlRIN4 substrate previously implicated in PTO-signaling. Thus, HopZ3 disrupts the functions of multiple immune components and the effectors that trigger them, leading to increased susceptibility to infection. Finally, mass spectrometry used to map specific acetylated residues confirmed HopZ3’s unusual capacity to modify histidine in addition to serine, threonine and lysine residues. By secreting virulence proteins (effectors) into their hosts, pathogenic bacteria hijack host cellular processes to promote bacterial colonization and disease development. For the plant pathogen Pseudomonas syringae, the coordinated action of effectors often mediates modifications of host defense proteins to inhibit their function. However, plants have evolved the ability to induce innate immunity upon recognition of effector-induced modifications of host proteins. How do pathogens circumvent the immune-inducing activity of certain effectors? They deploy more effectors to suppress these defenses. HopZ3, an acetyltransferase from P. syringae, is unique among plant pathogen effectors characterized so far in its ability to modify not only multiple components of the effector-triggered immune pathway, but also the triggering effector itself. Through the direct acetylation of residues involved in the interaction and activation of the bacterial effector AvrPto1Psy and tomato kinase PTO, HopZ3 modifications disrupt their binding and block phosphorylations necessary for immune induction. Additionally, HopZ3 acetylates other possible components in the PTO signaling pathway, including activation sites in SlRIPK kinase, leading to suppression of its activity and reduced phosphorylation of SlRIN4s. Our study emphasizes the importance of HopZ3-dependent acetylation of immune complexes and bacterial effectors across plant species in the suppression of effector-induced immunity.
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Affiliation(s)
- Joanna Jeleńska
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, Illinois, United States of America
| | - Jiyoung Lee
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, Illinois, United States of America
| | - Andrew J. Manning
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, Illinois, United States of America
| | - Donald J. Wolfgeher
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, Illinois, United States of America
| | - Youngjoo Ahn
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, Illinois, United States of America
| | - George Walters-Marrah
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, Illinois, United States of America
| | - Ivan E. Lopez
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, Illinois, United States of America
| | - Lissette Garcia
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, Illinois, United States of America
| | - Sheri A. McClerklin
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, Illinois, United States of America
| | - Richard W. Michelmore
- The Genome Center & Department of Plant Sciences, University of California, Davis, California, United States of America
| | - Stephen J. Kron
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, Illinois, United States of America
| | - Jean T. Greenberg
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, Illinois, United States of America
- * E-mail:
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7
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Manes N, Brauer EK, Hepworth S, Subramaniam R. MAMP and DAMP signaling contributes resistance to Fusarium graminearum in Arabidopsis. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:6628-6639. [PMID: 34405877 DOI: 10.1093/jxb/erab285] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Accepted: 08/06/2021] [Indexed: 05/19/2023]
Abstract
Plants perceive externally produced microbe-associated molecular patterns (MAMPs) and endogenously produced danger-associated molecular patterns (DAMPs) to activate inducible immunity. While several inducible immune responses have been observed during Fusarium graminearum infection, the identity of the signaling pathways involved is only partly known. We screened 227 receptor kinase and innate immune response genes in Arabidopsis to identify nine genes with a role in F. graminearum resistance. Resistance-promoting genes included the chitin receptors LYK5 and CERK1, and the reactive oxygen species (ROS)-producing NADPH oxidase RbohF, which were required for full inducible immune responses during infection. Two of the genes identified in our screen, APEX and the PAMP-induced peptide 1 (PIP1) DAMP receptor RLK7, repressed F. graminearum resistance. Both RbohF and RLK7 were required for full chitin-induced immune responses and PIP1 precursor expression was induced by chitin and F. graminearum infection. Together, this indicates that F. graminearum resistance is mediated by MAMP and DAMP signaling pathways and that chitin-induced signaling is enhanced by PIP1 perception and ROS production.
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Affiliation(s)
- Nimrat Manes
- Ottawa Research and Development Centre, Agriculture and Agri-Food Canada, Ottawa, ON K1A 0C6, Canada
- Carleton University, Department of Biology, 1125 Colonel By Dr., Ottawa, ON K1S 5B6, Canada
| | - Elizabeth K Brauer
- Ottawa Research and Development Centre, Agriculture and Agri-Food Canada, Ottawa, ON K1A 0C6, Canada
| | - Shelley Hepworth
- Carleton University, Department of Biology, 1125 Colonel By Dr., Ottawa, ON K1S 5B6, Canada
| | - Rajagopal Subramaniam
- Ottawa Research and Development Centre, Agriculture and Agri-Food Canada, Ottawa, ON K1A 0C6, Canada
- Carleton University, Department of Biology, 1125 Colonel By Dr., Ottawa, ON K1S 5B6, Canada
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8
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Delplace F, Huard-Chauveau C, Dubiella U, Khafif M, Alvarez E, Langin G, Roux F, Peyraud R, Roby D. Robustness of plant quantitative disease resistance is provided by a decentralized immune network. Proc Natl Acad Sci U S A 2020; 117:18099-18109. [PMID: 32669441 PMCID: PMC7395444 DOI: 10.1073/pnas.2000078117] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Quantitative disease resistance (QDR) represents the predominant form of resistance in natural populations and crops. Surprisingly, very limited information exists on the biomolecular network of the signaling machineries underlying this form of plant immunity. This lack of information may result from its complex and quantitative nature. Here, we used an integrative approach including genomics, network reconstruction, and mutational analysis to identify and validate molecular networks that control QDR in Arabidopsis thaliana in response to the bacterial pathogen Xanthomonas campestris To tackle this challenge, we first performed a transcriptomic analysis focused on the early stages of infection and using transgenic lines deregulated for the expression of RKS1, a gene underlying a QTL conferring quantitative and broad-spectrum resistance to XcampestrisRKS1-dependent gene expression was shown to involve multiple cellular activities (signaling, transport, and metabolism processes), mainly distinct from effector-triggered immunity (ETI) and pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) responses already characterized in Athaliana Protein-protein interaction network reconstitution then revealed a highly interconnected and distributed RKS1-dependent network, organized in five gene modules. Finally, knockout mutants for 41 genes belonging to the different functional modules of the network revealed that 76% of the genes and all gene modules participate partially in RKS1-mediated resistance. However, these functional modules exhibit differential robustness to genetic mutations, indicating that, within the decentralized structure of the QDR network, some modules are more resilient than others. In conclusion, our work sheds light on the complexity of QDR and provides comprehensive understanding of a QDR immune network.
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Affiliation(s)
- Florent Delplace
- Laboratoire des Interactions Plantes-Microorganismes, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement, CNRS, Université de Toulouse, 31326 Castanet-Tolosan, France
| | - Carine Huard-Chauveau
- Laboratoire des Interactions Plantes-Microorganismes, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement, CNRS, Université de Toulouse, 31326 Castanet-Tolosan, France
| | - Ullrich Dubiella
- Laboratoire des Interactions Plantes-Microorganismes, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement, CNRS, Université de Toulouse, 31326 Castanet-Tolosan, France
- KWS SAAT SE & Co, 37574 Einbeck, Germany
| | - Mehdi Khafif
- Laboratoire des Interactions Plantes-Microorganismes, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement, CNRS, Université de Toulouse, 31326 Castanet-Tolosan, France
| | - Eva Alvarez
- Laboratoire des Interactions Plantes-Microorganismes, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement, CNRS, Université de Toulouse, 31326 Castanet-Tolosan, France
| | - Gautier Langin
- Laboratoire des Interactions Plantes-Microorganismes, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement, CNRS, Université de Toulouse, 31326 Castanet-Tolosan, France
| | - Fabrice Roux
- Laboratoire des Interactions Plantes-Microorganismes, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement, CNRS, Université de Toulouse, 31326 Castanet-Tolosan, France
| | - Rémi Peyraud
- Laboratoire des Interactions Plantes-Microorganismes, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement, CNRS, Université de Toulouse, 31326 Castanet-Tolosan, France
- iMean, 31520 Toulouse, France
| | - Dominique Roby
- Laboratoire des Interactions Plantes-Microorganismes, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement, CNRS, Université de Toulouse, 31326 Castanet-Tolosan, France;
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