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Chen J, Zhang X, Bernoux M, Rathjen JP, Dodds PN. Plant Toll/interleukin-1 receptor/resistance protein domains physically associate with enhanced disease susceptibility1 family proteins in immune signaling. iScience 2024; 27:108817. [PMID: 38533452 PMCID: PMC10964261 DOI: 10.1016/j.isci.2024.108817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2023] [Revised: 11/09/2023] [Accepted: 01/02/2024] [Indexed: 03/28/2024] Open
Abstract
Plant Toll/interleukin-1 receptor/resistance protein (TIR) type nucleotide-binding and leucine-rich repeat immune receptors (NLRs) require enhanced disease susceptibility 1 (EDS1) family proteins and the helper NLRs NRG1 and ADR1 for immune activation. We show that the NbEDS1-NbSAG101b-NbNRG1 signaling pathway in N. benthamiana is necessary for cell death signaling by TIR-NLRs from a range of plant species, suggesting a universal requirement for this module in TIR-NLR-mediated cell death in N. benthamiana. We also find that TIR domains physically associate with NbEDS1, NbPAD4, and NbSAG101 in planta, independently of each other. Furthermore, NbNRG1 associates with NbSAG101b, but not with other EDS1 family members, via its C-terminal EP domain. Physical interaction between activated TIRs and EDS1 signaling complexes may facilitate the transfer of low abundance products of TIR catalytic activity or alter TIR catalytic activity to favor the production of EDS1 heterodimer ligands.
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Affiliation(s)
- Jian Chen
- Commonwealth Scientific and Industrial Research Organization, Agriculture and Food, Canberra, ACT 2601, Australia
- Research School of Biology, The Australian National University, Canberra, ACT 2600, Australia
| | - Xiaoxiao Zhang
- Research School of Biology, The Australian National University, Canberra, ACT 2600, Australia
| | - Maud Bernoux
- Laboratoire des interactions plantes-microbes-environnement, Université de Toulouse, INRAE, CNRS, Castanet-Tolosan, France
| | - John P. Rathjen
- Research School of Biology, The Australian National University, Canberra, ACT 2600, Australia
| | - Peter N. Dodds
- Commonwealth Scientific and Industrial Research Organization, Agriculture and Food, Canberra, ACT 2601, Australia
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2
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Bernoux M, Chen J, Zhang X, Newell K, Hu J, Deslandes L, Dodds P. Subcellular localization requirements and specificities for plant immune receptor Toll-interleukin-1 receptor signaling. Plant J 2023. [PMID: 36932864 DOI: 10.1111/tpj.16195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 02/24/2023] [Accepted: 03/01/2023] [Indexed: 06/02/2023]
Abstract
Recent work shed light on how plant intracellular immune receptors of the nucleotide-binding leucine-rich repeat (NLR) family are activated upon pathogen effector recognition to trigger immune responses. Activation of Toll-interleukin-1 receptor (TIR) domain-containing NLRs (TNLs) induces receptor oligomerization and close proximity of the TIR domain, which is required for TIR enzymatic activity. TIR-catalyzed small signaling molecules bind to EDS1 family heterodimers and subsequently activate downstream helper NLRs, which function as Ca2+ permeable channel to activate immune responses eventually leading to cell death. Subcellular localization requirements of TNLs and signaling partners are not well understood, although they are required to understand fully the mechanisms underlying NLR early signaling. TNLs show diverse subcellular localization while EDS1 shows nucleocytosolic localization. Here, we studied the impact of TIR and EDS1 mislocalization on the signaling activation of different TNLs. In Nicotiana benthamiana, our results suggest that close proximity of TIR domains isolated from flax L6 and Arabidopsis RPS4 and SNC1 TNLs drives signaling activation from different cell compartments. Nevertheless, both Golgi-membrane anchored L6 and nucleocytosolic RPS4 have the same requirements for EDS1 subcellular localization in Arabidopsis thaliana. By using mislocalized variants of EDS1, we found that autoimmune L6 and RPS4 TIR domain can induce seedling cell death when EDS1 is present in the cytosol. However, when EDS1 is restricted to the nucleus, both induce a stunting phenotype but no cell death. Our data point out the importance of thoroughly investigating the dynamics of TNLs and signaling partners subcellular localization to understand TNL signaling fully.
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Affiliation(s)
- Maud Bernoux
- Laboratoire des Interactions Plantes-Microbes-Environnement (LIPME), UMR 2594/441 CNRS, INRAE, 31326, Castanet-Tolosan, France
| | - Jian Chen
- Agriculture and Food, Commonwealth Scientific and Industrial Research Organization, Canberra, ACT 2601, Australia
| | - Xiaoxiao Zhang
- Research School of Biology, Australian National University, Canberra, ACT 2601, Australia
| | - Kim Newell
- Agriculture and Food, Commonwealth Scientific and Industrial Research Organization, Canberra, ACT 2601, Australia
| | - Jian Hu
- Department of Biochemistry and Molecular Biology, College of Biological Sciences, China Agricultural University, Beijing, 100094, People's Republic of China
| | - Laurent Deslandes
- Laboratoire des Interactions Plantes-Microbes-Environnement (LIPME), UMR 2594/441 CNRS, INRAE, 31326, Castanet-Tolosan, France
| | - Peter Dodds
- Agriculture and Food, Commonwealth Scientific and Industrial Research Organization, Canberra, ACT 2601, Australia
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Bernoux M, Zetzsche H, Stuttmann J. Connecting the dots between cell surface- and intracellular-triggered immune pathways in plants. Curr Opin Plant Biol 2022; 69:102276. [PMID: 36001920 DOI: 10.1016/j.pbi.2022.102276] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 06/16/2022] [Accepted: 07/06/2022] [Indexed: 06/15/2023]
Abstract
Plants can detect microbial molecules via surface-localized pattern-recognition receptors (PRRs) and intracellular immune receptors from the nucleotide-binding, leucine-rich repeat receptor (NLR) family. The corresponding pattern-triggered (PTI) and effector-triggered (ETI) immunity were long considered separate pathways, although they converge on largely similar cellular responses, such as calcium influx and overlapping gene reprogramming. A number of studies recently uncovered genetic and molecular interconnections between PTI and ETI, highlighting the complexity of the plant immune network. Notably, PRR- and NLR-mediated immune responses require and potentiate each other to reach an optimal immune output. How PTI and ETI connect to confer robust immunity in different plant species, including crops will be an exciting future research area.
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Affiliation(s)
- Maud Bernoux
- Laboratoire des Interactions Plantes-Microbes-Environnement (LIPME), INRAE, CNRS, Université de Toulouse, F-31326 Castanet-Tolosan, France
| | - Holger Zetzsche
- Institute for Resistance Research and Stress Tolerance, Federal Research Centre for Cultivated Plants, Julius Kühn-Institute (JKI), Quedlinburg, Germany
| | - Johannes Stuttmann
- Institute for Biosafety in Plant Biotechnology, Federal Research Centre for Cultivated Plants, Julius Kühn-Institute (JKI), Quedlinburg, Germany.
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Tasset C, Bernoux M, Jauneau A, Pouzet C, Brière C, Kieffer-Jacquinod S, Rivas S, Marco Y, Deslandes L. Correction: Autoacetylation of the Ralstonia solanacearum Effector PopP2 Targets a Lysine Residue Essential for RRS1-R-Mediated Immunity in Arabidopsis. PLoS Pathog 2022; 18:e1010368. [PMID: 35235614 PMCID: PMC8890644 DOI: 10.1371/journal.ppat.1010368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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5
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Zhang X, Farah N, Rolston L, Ericsson DJ, Catanzariti A, Bernoux M, Ve T, Bendak K, Chen C, Mackay JP, Lawrence GJ, Hardham A, Ellis JG, Williams SJ, Dodds PN, Jones DA, Kobe B. Crystal structure of the Melampsora lini effector AvrP reveals insights into a possible nuclear function and recognition by the flax disease resistance protein P. Mol Plant Pathol 2018; 19:1196-1209. [PMID: 28817232 PMCID: PMC6638141 DOI: 10.1111/mpp.12597] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2017] [Revised: 08/15/2017] [Accepted: 08/15/2017] [Indexed: 05/23/2023]
Abstract
The effector protein AvrP is secreted by the flax rust fungal pathogen (Melampsora lini) and recognized specifically by the flax (Linum usitatissimum) P disease resistance protein, leading to effector-triggered immunity. To investigate the biological function of this effector and the mechanisms of specific recognition by the P resistance protein, we determined the crystal structure of AvrP. The structure reveals an elongated zinc-finger-like structure with a novel interleaved zinc-binding topology. The residues responsible for zinc binding are conserved in AvrP effector variants and mutations of these motifs result in a loss of P-mediated recognition. The first zinc-coordinating region of the structure displays a positively charged surface and shows some limited similarities to nucleic acid-binding and chromatin-associated proteins. We show that the majority of the AvrP protein accumulates in the plant nucleus when transiently expressed in Nicotiana benthamiana cells, suggesting a nuclear pathogenic function. Polymorphic residues in AvrP and its allelic variants map to the protein surface and could be associated with differences in recognition specificity. Several point mutations of residues on the non-conserved surface patch result in a loss of recognition by P, suggesting that these residues are required for recognition.
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Affiliation(s)
- Xiaoxiao Zhang
- School of Chemistry and Molecular BiosciencesAustralian Infectious Diseases Research Centre and Institute for Molecular Bioscience, University of QueenslandBrisbaneQueensland 4072Australia
- Commonwealth Scientific and Industrial Research Organisation Agriculture and FoodCanberraAustralian Capital Territory 2601Australia
| | - Nadya Farah
- Division of Plant SciencesResearch School of Biology, Australian National University, ActonAustralian Capital Territory 2601Australia
| | - Laura Rolston
- Division of Plant SciencesResearch School of Biology, Australian National University, ActonAustralian Capital Territory 2601Australia
| | - Daniel J. Ericsson
- School of Chemistry and Molecular BiosciencesAustralian Infectious Diseases Research Centre and Institute for Molecular Bioscience, University of QueenslandBrisbaneQueensland 4072Australia
- Australian Synchrotron, Macromolecular crystallographyClaytonVictoria 3168Australia
| | - Ann‐Maree Catanzariti
- Division of Plant SciencesResearch School of Biology, Australian National University, ActonAustralian Capital Territory 2601Australia
| | - Maud Bernoux
- Commonwealth Scientific and Industrial Research Organisation Agriculture and FoodCanberraAustralian Capital Territory 2601Australia
| | - Thomas Ve
- School of Chemistry and Molecular BiosciencesAustralian Infectious Diseases Research Centre and Institute for Molecular Bioscience, University of QueenslandBrisbaneQueensland 4072Australia
- Institute for Glycomics, Griffith UniversitySouthportQueensland 4222Australia
| | - Katerina Bendak
- School of Molecular BioscienceUniversity of SydneySydneyNew South Wales 2006Australia
| | - Chunhong Chen
- Commonwealth Scientific and Industrial Research Organisation Agriculture and FoodCanberraAustralian Capital Territory 2601Australia
| | - Joel P. Mackay
- School of Molecular BioscienceUniversity of SydneySydneyNew South Wales 2006Australia
| | - Gregory J. Lawrence
- Commonwealth Scientific and Industrial Research Organisation Agriculture and FoodCanberraAustralian Capital Territory 2601Australia
| | - Adrienne Hardham
- Division of Plant SciencesResearch School of Biology, Australian National University, ActonAustralian Capital Territory 2601Australia
| | - Jeffrey G. Ellis
- Commonwealth Scientific and Industrial Research Organisation Agriculture and FoodCanberraAustralian Capital Territory 2601Australia
| | - Simon J. Williams
- School of Chemistry and Molecular BiosciencesAustralian Infectious Diseases Research Centre and Institute for Molecular Bioscience, University of QueenslandBrisbaneQueensland 4072Australia
- Division of Plant SciencesResearch School of Biology, Australian National University, ActonAustralian Capital Territory 2601Australia
| | - Peter N. Dodds
- Commonwealth Scientific and Industrial Research Organisation Agriculture and FoodCanberraAustralian Capital Territory 2601Australia
| | - David A. Jones
- Division of Plant SciencesResearch School of Biology, Australian National University, ActonAustralian Capital Territory 2601Australia
| | - Bostjan Kobe
- School of Chemistry and Molecular BiosciencesAustralian Infectious Diseases Research Centre and Institute for Molecular Bioscience, University of QueenslandBrisbaneQueensland 4072Australia
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6
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Chen J, Upadhyaya NM, Ortiz D, Sperschneider J, Li F, Bouton C, Breen S, Dong C, Xu B, Zhang X, Mago R, Newell K, Xia X, Bernoux M, Taylor JM, Steffenson B, Jin Y, Zhang P, Kanyuka K, Figueroa M, Ellis JG, Park RF, Dodds PN. Loss of AvrSr50 by somatic exchange in stem rust leads to virulence for Sr50 resistance in wheat. Science 2018; 358:1607-1610. [PMID: 29269475 DOI: 10.1126/science.aao4810] [Citation(s) in RCA: 120] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 11/03/2017] [Indexed: 01/03/2023]
Abstract
Race-specific resistance genes protect the global wheat crop from stem rust disease caused by Puccinia graminis f. sp. tritici (Pgt) but are often overcome owing to evolution of new virulent races of the pathogen. To understand virulence evolution in Pgt, we identified the protein ligand (AvrSr50) recognized by the Sr50 resistance protein. A spontaneous mutant of Pgt virulent to Sr50 contained a 2.5 mega-base pair loss-of-heterozygosity event. A haustorial secreted protein from this region triggers Sr50-dependent defense responses in planta and interacts directly with the Sr50 protein. Virulence alleles of AvrSr50 have arisen through DNA insertion and sequence divergence, and our data provide molecular evidence that in addition to sexual recombination, somatic exchange can play a role in the emergence of new virulence traits in Pgt.
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Affiliation(s)
- Jiapeng Chen
- Plant Breeding Institute, School of Life and Environmental Sciences, University of Sydney, Cobbitty, NSW, Australia.,Commonwealth Scientific and Industrial Research Organisation, Agriculture and Food, Canberra, ACT, Australia.,Judith and David Coffey Life Lab, Charles Perkins Centre, University of Sydney
| | - Narayana M Upadhyaya
- Commonwealth Scientific and Industrial Research Organisation, Agriculture and Food, Canberra, ACT, Australia
| | - Diana Ortiz
- Commonwealth Scientific and Industrial Research Organisation, Agriculture and Food, Canberra, ACT, Australia
| | - Jana Sperschneider
- Centre for Environment and Life Sciences, Commonwealth Scientific and Industrial Research Organisation, Agriculture and Food, Perth, WA, Australia
| | - Feng Li
- Department of Plant Pathology and The Stakman-Borlaug Center for Sustainable Plant Health, University of Minnesota, St. Paul, MN, USA
| | - Clement Bouton
- Biointeractions and Crop Protection, Rothamsted Research, Harpenden, AL5 2JQ, UK
| | - Susan Breen
- Commonwealth Scientific and Industrial Research Organisation, Agriculture and Food, Canberra, ACT, Australia
| | - Chongmei Dong
- Plant Breeding Institute, School of Life and Environmental Sciences, University of Sydney, Cobbitty, NSW, Australia
| | - Bo Xu
- Commonwealth Scientific and Industrial Research Organisation, Agriculture and Food, Canberra, ACT, Australia
| | - Xiaoxiao Zhang
- Commonwealth Scientific and Industrial Research Organisation, Agriculture and Food, Canberra, ACT, Australia
| | - Rohit Mago
- Commonwealth Scientific and Industrial Research Organisation, Agriculture and Food, Canberra, ACT, Australia
| | - Kim Newell
- Commonwealth Scientific and Industrial Research Organisation, Agriculture and Food, Canberra, ACT, Australia
| | - Xiaodi Xia
- Commonwealth Scientific and Industrial Research Organisation, Agriculture and Food, Canberra, ACT, Australia
| | - Maud Bernoux
- Commonwealth Scientific and Industrial Research Organisation, Agriculture and Food, Canberra, ACT, Australia
| | - Jennifer M Taylor
- Commonwealth Scientific and Industrial Research Organisation, Agriculture and Food, Canberra, ACT, Australia
| | - Brian Steffenson
- Department of Plant Pathology and The Stakman-Borlaug Center for Sustainable Plant Health, University of Minnesota, St. Paul, MN, USA
| | - Yue Jin
- Department of Plant Pathology and The Stakman-Borlaug Center for Sustainable Plant Health, University of Minnesota, St. Paul, MN, USA.,United States Department of Agriculture-Agricultural Research Service (USDA-ARS), Cereal Disease Laboratory, St. Paul, MN, USA
| | - Peng Zhang
- Plant Breeding Institute, School of Life and Environmental Sciences, University of Sydney, Cobbitty, NSW, Australia
| | - Kostya Kanyuka
- Biointeractions and Crop Protection, Rothamsted Research, Harpenden, AL5 2JQ, UK
| | - Melania Figueroa
- Department of Plant Pathology and The Stakman-Borlaug Center for Sustainable Plant Health, University of Minnesota, St. Paul, MN, USA
| | - Jeffrey G Ellis
- Commonwealth Scientific and Industrial Research Organisation, Agriculture and Food, Canberra, ACT, Australia
| | - Robert F Park
- Plant Breeding Institute, School of Life and Environmental Sciences, University of Sydney, Cobbitty, NSW, Australia
| | - Peter N Dodds
- Commonwealth Scientific and Industrial Research Organisation, Agriculture and Food, Canberra, ACT, Australia
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7
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Abstract
The first plant disease resistance (R) genes were identified and cloned more than two decades ago. Since then, many more R genes have been identified and characterized in numerous plant pathosystems. Most of these encode members of the large family of intracellular NLRs (NOD-like receptors), which also includes animal immune receptors. New discoveries in this expanding field of research provide new elements for our understanding of plant NLR function. But what do we know about plant NLR function today? Genetic, structural, and functional analyses have uncovered a number of commonalities and differences in pathogen recognition strategies as well as how NLRs are regulated and activate defense signaling, but many unknowns remain. This review gives an update on the latest discoveries and breakthroughs in this field, with an emphasis on structural findings and some comparison to animal NLRs, which can provide additional insights and paradigms in plant NLR function.
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Affiliation(s)
- Xiaoxiao Zhang
- Commonwealth Scientific and Industrial Research Organisation, Agriculture and Food, Canberra, ACT 2601, Australia;
| | - Peter N Dodds
- Commonwealth Scientific and Industrial Research Organisation, Agriculture and Food, Canberra, ACT 2601, Australia;
| | - Maud Bernoux
- Commonwealth Scientific and Industrial Research Organisation, Agriculture and Food, Canberra, ACT 2601, Australia;
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8
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Zhang X, Bernoux M, Bentham AR, Newman TE, Ve T, Casey LW, Raaymakers TM, Hu J, Croll TI, Schreiber KJ, Staskawicz BJ, Anderson PA, Sohn KH, Williams SJ, Dodds PN, Kobe B. Multiple functional self-association interfaces in plant TIR domains. Proc Natl Acad Sci U S A 2017; 114:E2046-E2052. [PMID: 28159890 PMCID: PMC5347627 DOI: 10.1073/pnas.1621248114] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The self-association of Toll/interleukin-1 receptor/resistance protein (TIR) domains has been implicated in signaling in plant and animal immunity receptors. Structure-based studies identified different TIR-domain dimerization interfaces required for signaling of the plant nucleotide-binding oligomerization domain-like receptors (NLRs) L6 from flax and disease resistance protein RPS4 from Arabidopsis Here we show that the crystal structure of the TIR domain from the Arabidopsis NLR suppressor of npr1-1, constitutive 1 (SNC1) contains both an L6-like interface involving helices αD and αE (DE interface) and an RPS4-like interface involving helices αA and αE (AE interface). Mutations in either the AE- or DE-interface region disrupt cell-death signaling activity of SNC1, L6, and RPS4 TIR domains and full-length L6 and RPS4. Self-association of L6 and RPS4 TIR domains is affected by mutations in either region, whereas only AE-interface mutations affect SNC1 TIR-domain self-association. We further show two similar interfaces in the crystal structure of the TIR domain from the Arabidopsis NLR recognition of Peronospora parasitica 1 (RPP1). These data demonstrate that both the AE and DE self-association interfaces are simultaneously required for self-association and cell-death signaling in diverse plant NLRs.
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Affiliation(s)
- Xiaoxiao Zhang
- School of Chemistry and Molecular Biosciences, Australian Infectious Diseases Research Centre and Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD 4072, Australia
- Agriculture and Food, Commonwealth Scientific and Industrial Research Organisation, Canberra, ACT 2601, Australia
| | - Maud Bernoux
- Agriculture and Food, Commonwealth Scientific and Industrial Research Organisation, Canberra, ACT 2601, Australia;
| | - Adam R Bentham
- School of Chemistry and Molecular Biosciences, Australian Infectious Diseases Research Centre and Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD 4072, Australia
- School of Biological Sciences, Faculty of Science and Engineering, Flinders University, Adelaide, SA 5001, Australia
| | - Toby E Newman
- Department of Life Sciences, and School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, Pohang, Gyeongbuk 790-784, Republic of Korea
- Bioprotection Research Centre, Institute of Agriculture and Environment, Massey University, Palmerston North 4442, New Zealand
| | - Thomas Ve
- School of Chemistry and Molecular Biosciences, Australian Infectious Diseases Research Centre and Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD 4072, Australia
- Institute for Glycomics, Griffith University, Southport, QLD 4222, Australia
| | - Lachlan W Casey
- School of Chemistry and Molecular Biosciences, Australian Infectious Diseases Research Centre and Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD 4072, Australia
| | - Tom M Raaymakers
- Agriculture and Food, Commonwealth Scientific and Industrial Research Organisation, Canberra, ACT 2601, Australia
- Department of Biology, Plant-Microbe Interactions, Utrecht University, 3584 CH Utrecht, The Netherlands
| | - Jian Hu
- Agriculture and Food, Commonwealth Scientific and Industrial Research Organisation, Canberra, ACT 2601, Australia
- College of Biological Sciences, China Agricultural University, Beijing 100094, People's Republic of China
| | - Tristan I Croll
- School of Biomedical Sciences, Queensland University of Technology, Brisbane, QLD 4001, Australia
| | - Karl J Schreiber
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720
| | - Brian J Staskawicz
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720;
| | - Peter A Anderson
- School of Biological Sciences, Faculty of Science and Engineering, Flinders University, Adelaide, SA 5001, Australia
| | - Kee Hoon Sohn
- Department of Life Sciences, and School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, Pohang, Gyeongbuk 790-784, Republic of Korea
- Bioprotection Research Centre, Institute of Agriculture and Environment, Massey University, Palmerston North 4442, New Zealand
| | - Simon J Williams
- School of Chemistry and Molecular Biosciences, Australian Infectious Diseases Research Centre and Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD 4072, Australia;
- Research School of Biology, College of Medicine, Biology, and Environment, Australian National University, Canberra, ACT 0200, Australia
| | - Peter N Dodds
- Agriculture and Food, Commonwealth Scientific and Industrial Research Organisation, Canberra, ACT 2601, Australia;
| | - Bostjan Kobe
- School of Chemistry and Molecular Biosciences, Australian Infectious Diseases Research Centre and Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD 4072, Australia;
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Cesari S, Moore J, Chen C, Webb D, Periyannan S, Mago R, Bernoux M, Lagudah ES, Dodds PN. Cytosolic activation of cell death and stem rust resistance by cereal MLA-family CC-NLR proteins. Proc Natl Acad Sci U S A 2016; 113:10204-9. [PMID: 27555587 PMCID: PMC5018743 DOI: 10.1073/pnas.1605483113] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Plants possess intracellular immune receptors designated "nucleotide-binding domain and leucine-rich repeat" (NLR) proteins that translate pathogen-specific recognition into disease-resistance signaling. The wheat immune receptors Sr33 and Sr50 belong to the class of coiled-coil (CC) NLRs. They confer resistance against a broad spectrum of field isolates of Puccinia graminis f. sp. tritici, including the Ug99 lineage, and are homologs of the barley powdery mildew-resistance protein MLA10. Here, we show that, similarly to MLA10, the Sr33 and Sr50 CC domains are sufficient to induce cell death in Nicotiana benthamiana Autoactive CC domains and full-length Sr33 and Sr50 proteins self-associate in planta In contrast, truncated CC domains equivalent in size to an MLA10 fragment for which a crystal structure was previously determined fail to induce cell death and do not self-associate. Mutations in the truncated region also abolish self-association and cell-death signaling. Analysis of Sr33 and Sr50 CC domains fused to YFP and either nuclear localization or nuclear export signals in N benthamiana showed that cell-death induction occurs in the cytosol. In stable transgenic wheat plants, full-length Sr33 proteins targeted to the cytosol provided rust resistance, whereas nuclear-targeted Sr33 was not functional. These data are consistent with CC-mediated induction of both cell-death signaling and stem rust resistance in the cytosolic compartment, whereas previous research had suggested that MLA10-mediated cell-death and disease resistance signaling occur independently, in the cytosol and nucleus, respectively.
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Affiliation(s)
- Stella Cesari
- Commonwealth Scientific and Industrial Research Organization Agriculture, Canberra, ACT 2601, Australia
| | - John Moore
- Commonwealth Scientific and Industrial Research Organization Agriculture, Canberra, ACT 2601, Australia
| | - Chunhong Chen
- Commonwealth Scientific and Industrial Research Organization Agriculture, Canberra, ACT 2601, Australia
| | - Daryl Webb
- Centre for Advanced Microscopy, Australian National University, Canberra, ACT 0200, Australia
| | - Sambasivam Periyannan
- Commonwealth Scientific and Industrial Research Organization Agriculture, Canberra, ACT 2601, Australia
| | - Rohit Mago
- Commonwealth Scientific and Industrial Research Organization Agriculture, Canberra, ACT 2601, Australia
| | - Maud Bernoux
- Commonwealth Scientific and Industrial Research Organization Agriculture, Canberra, ACT 2601, Australia
| | - Evans S Lagudah
- Commonwealth Scientific and Industrial Research Organization Agriculture, Canberra, ACT 2601, Australia
| | - Peter N Dodds
- Commonwealth Scientific and Industrial Research Organization Agriculture, Canberra, ACT 2601, Australia;
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10
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Bernoux M, Burdett H, Williams SJ, Zhang X, Chen C, Newell K, Lawrence GJ, Kobe B, Ellis JG, Anderson PA, Dodds PN. Comparative Analysis of the Flax Immune Receptors L6 and L7 Suggests an Equilibrium-Based Switch Activation Model. Plant Cell 2016; 28:146-59. [PMID: 26744216 PMCID: PMC4746675 DOI: 10.1105/tpc.15.00303] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Revised: 12/10/2015] [Accepted: 01/06/2016] [Indexed: 05/18/2023]
Abstract
NOD-like receptors (NLRs) are central components of the plant immune system. L6 is a Toll/interleukin-1 receptor (TIR) domain-containing NLR from flax (Linum usitatissimum) conferring immunity to the flax rust fungus. Comparison of L6 to the weaker allele L7 identified two polymorphic regions in the TIR and the nucleotide binding (NB) domains that regulate both effector ligand-dependent and -independent cell death signaling as well as nucleotide binding to the receptor. This suggests that a negative functional interaction between the TIR and NB domains holds L7 in an inactive/ADP-bound state more tightly than L6, hence decreasing its capacity to adopt the active/ATP-bound state and explaining its weaker activity in planta. L6 and L7 variants with a more stable ADP-bound state failed to bind to AvrL567 in yeast two-hybrid assays, while binding was detected to the signaling active variants. This contrasts with current models predicting that effectors bind to inactive receptors to trigger activation. Based on the correlation between nucleotide binding, effector interaction, and immune signaling properties of L6/L7 variants, we propose that NLRs exist in an equilibrium between ON and OFF states and that effector binding to the ON state stabilizes this conformation, thereby shifting the equilibrium toward the active form of the receptor to trigger defense signaling.
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Affiliation(s)
| | - Hayden Burdett
- School of Biological Sciences, Flinders University, Adelaide SA 5001, Australia
| | - Simon J Williams
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane QLD 4072, Australia
| | | | | | - Kim Newell
- CSIRO Agriculture, Canberra ACT 2601, Australia
| | | | - Bostjan Kobe
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane QLD 4072, Australia
| | | | - Peter A Anderson
- School of Biological Sciences, Flinders University, Adelaide SA 5001, Australia
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11
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Kobe B, Ve T, Williams S, Zhang X, Wan L, Alaidarous M, Bernoux M, Sohn KH, Jones J, Landsberg M, Dodds P. General mechanism of function of TIR domains. Acta Crystallogr A Found Adv 2015. [DOI: 10.1107/s2053273315099532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Cesari S, Bernoux M, Moncuquet P, Kroj T, Dodds PN. A novel conserved mechanism for plant NLR protein pairs: the "integrated decoy" hypothesis. Front Plant Sci 2014; 5:606. [PMID: 25506347 DOI: 10.3389/fpls.2014.00606/abstract] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 10/17/2014] [Indexed: 05/26/2023]
Abstract
Plant immunity is often triggered by the specific recognition of pathogen effectors by intracellular nucleotide-binding, leucine-rich repeat receptors (NLR). Plant NLRs contain an N-terminal signaling domain that is mostly represented by either a Toll-interleukin1 receptor (TIR) domain or a coiled coil (CC) domain. In many cases, single NLR proteins are sufficient for both effector recognition and signaling activation. However, many paired NLRs have now been identified where both proteins are required to confer resistance to pathogens. Recent detailed studies on the Arabidopsis thaliana TIR-NLR pair RRS1 and RPS4 and on the rice CC-NLR pair RGA4 and RGA5 have revealed for the first time how such protein pairs function together. In both cases, the paired partners interact physically to form a hetero-complex receptor in which each partner plays distinct roles in effector recognition or signaling activation, highlighting a conserved mode of action of NLR pairs across both monocotyledonous and dicotyledonous plants. We also describe an "integrated decoy" model for the function of these receptor complexes. In this model, a plant protein targeted by an effector has been duplicated and fused to one member of the NLR pair, where it acts as a bait to trigger defense signaling by the second NLR upon effector binding. This mechanism may be common to many other plant NLR pairs.
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Affiliation(s)
- Stella Cesari
- Institut National de la Recherche Agronomique, Unité Mixtes de Recherche Biology and Genetics of Plant-Pathogen Interactions Montpellier, France ; Centre de Coopération Internationale en Recherche Agronomique pour le Développement, Unité Mixtes de Recherche Biology and Genetics of Plant-Pathogen Interactions Montpellier, France ; Agriculture Flagship, Commonwealth Scientific and Industrial Research Organisation Canberra, ACT, Australia
| | - Maud Bernoux
- Agriculture Flagship, Commonwealth Scientific and Industrial Research Organisation Canberra, ACT, Australia
| | - Philippe Moncuquet
- Commonwealth Scientific and Industrial Research Organisation, Digital Productivity and Service Canberra, ACT, Australia
| | - Thomas Kroj
- Institut National de la Recherche Agronomique, Unité Mixtes de Recherche Biology and Genetics of Plant-Pathogen Interactions Montpellier, France ; Centre de Coopération Internationale en Recherche Agronomique pour le Développement, Unité Mixtes de Recherche Biology and Genetics of Plant-Pathogen Interactions Montpellier, France
| | - Peter N Dodds
- Agriculture Flagship, Commonwealth Scientific and Industrial Research Organisation Canberra, ACT, Australia
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Césari S, Kanzaki H, Fujiwara T, Bernoux M, Chalvon V, Kawano Y, Shimamoto K, Dodds P, Terauchi R, Kroj T. The NB-LRR proteins RGA4 and RGA5 interact functionally and physically to confer disease resistance. EMBO J 2014; 33:1941-59. [PMID: 25024433 PMCID: PMC4195788 DOI: 10.15252/embj.201487923] [Citation(s) in RCA: 222] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2014] [Revised: 05/20/2014] [Accepted: 06/05/2014] [Indexed: 12/27/2022] Open
Abstract
Plant resistance proteins of the class of nucleotide-binding and leucine-rich repeat domain proteins (NB-LRRs) are immune sensors which recognize pathogen-derived molecules termed avirulence (AVR) proteins. We show that RGA4 and RGA5, two NB-LRRs from rice, interact functionally and physically to mediate resistance to the fungal pathogen Magnaporthe oryzae and accomplish different functions in AVR recognition. RGA4 triggers an AVR-independent cell death that is repressed in the presence of RGA5 in both rice protoplasts and Nicotiana benthamiana. Upon recognition of the pathogen effector AVR-Pia by direct binding to RGA5, repression is relieved and cell death occurs. RGA4 and RGA5 form homo- and hetero-complexes and interact through their coiled-coil domains. Localization studies in rice protoplast suggest that RGA4 and RGA5 localize to the cytosol. Upon recognition of AVR-Pia, neither RGA4 nor RGA5 is re-localized to the nucleus. These results establish a model for the interaction of hetero-pairs of NB-LRRs in plants: RGA4 mediates cell death activation, while RGA5 acts as a repressor of RGA4 and as an AVR receptor.
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Affiliation(s)
- Stella Césari
- INRA UMR BGPI, Montpellier, France CIRAD UMR BGPI, Montpellier, France CSIRO Plant Industry, Canberra, ACT, Australia
| | | | - Tadashi Fujiwara
- Laboratory of Plant Molecular Genetics, Nara Institute of Science and Technology, Takayama Ikoma, Japan
| | | | - Véronique Chalvon
- INRA UMR BGPI, Montpellier, France CIRAD UMR BGPI, Montpellier, France
| | - Yoji Kawano
- Laboratory of Plant Molecular Genetics, Nara Institute of Science and Technology, Takayama Ikoma, Japan
| | - Ko Shimamoto
- Laboratory of Plant Molecular Genetics, Nara Institute of Science and Technology, Takayama Ikoma, Japan
| | - Peter Dodds
- CSIRO Plant Industry, Canberra, ACT, Australia
| | | | - Thomas Kroj
- INRA UMR BGPI, Montpellier, France CIRAD UMR BGPI, Montpellier, France
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14
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Williams S, Alaidarous M, Ve T, Zhang X, Valkov E, Bernoux M, Sohn K, Jones J, Dodds P, Kobe B. Common and distinct features of TIR domain function. Acta Crystallogr A Found Adv 2014. [DOI: 10.1107/s2053273314097575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
TIR (Toll/interleukin-1 receptor, resistance protein) domains feature in diverse proteins with functions in the immune system, such as animal TLRs (Toll-like receptors), plant NLRs (nucleotide binding, leucine-rich repeat) and bacterial virulence factors. It has been well established, especially through the work on TLRs, that signalling depends on regulated self-association of TIR domains. However, every single TIR domain structure has revealed a different association mode [1]. In the search for common features, we have targeted a number of TIR domains from mammals, plants and bacteria to characterize structurally. We have determined the crystal structures of the TIR domains from the human TLR adaptor protein MAL [1], the bacterial protein TcpB from Brucella melitensis [2] and the plant immune proteins L6 from flax [3] and SNC1, RPS4 and RRS1 from Arabidopsis (unpublished). In the case of the proteins RPS4 and RRS1, which work together as a protein complex to confer resistance to three different bacterial and fungal pathogens, we have determined, using linker-assisted crystallization, the first structure of a hetero-dimeric complex of TIR domains (Fig. 1). The association interface in this complex is conserved in the crystals of the TIR domains of RPS4 and RRS1 on their own, as well as in those of SNC1 and another Arabidopsis protein AT1G72930. Similarly, the dimerization interface observed in the structure of TcpB is conserved in the structure of the TIR domain-containing protein from Paracoccus denitrificans. We validated the association interfaces by site-directed mutagenesis coupled with a variety of cellular assays. As self-association is key to TIR domain function, our studies are finally revealing common features of the molecular function of TIR domains across phyla.
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Williams SJ, Sohn KH, Wan L, Bernoux M, Sarris PF, Segonzac C, Ve T, Ma Y, Saucet SB, Ericsson DJ, Casey LW, Lonhienne T, Winzor DJ, Zhang X, Coerdt A, Parker JE, Dodds PN, Kobe B, Jones JDG. Structural basis for assembly and function of a heterodimeric plant immune receptor. Science 2014; 344:299-303. [PMID: 24744375 DOI: 10.1126/science.1247357] [Citation(s) in RCA: 229] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Cytoplasmic plant immune receptors recognize specific pathogen effector proteins and initiate effector-triggered immunity. In Arabidopsis, the immune receptors RPS4 and RRS1 are both required to activate defense to three different pathogens. We show that RPS4 and RRS1 physically associate. Crystal structures of the N-terminal Toll-interleukin-1 receptor/resistance (TIR) domains of RPS4 and RRS1, individually and as a heterodimeric complex (respectively at 2.05, 1.75, and 2.65 angstrom resolution), reveal a conserved TIR/TIR interaction interface. We show that TIR domain heterodimerization is required to form a functional RRS1/RPS4 effector recognition complex. The RPS4 TIR domain activates effector-independent defense, which is inhibited by the RRS1 TIR domain through the heterodimerization interface. Thus, RPS4 and RRS1 function as a receptor complex in which the two components play distinct roles in recognition and signaling.
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Affiliation(s)
- Simon J Williams
- School of Chemistry and Molecular Biosciences and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, QLD 4072, Australia
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Cesari S, Bernoux M, Moncuquet P, Kroj T, Dodds PN. A novel conserved mechanism for plant NLR protein pairs: the "integrated decoy" hypothesis. Front Plant Sci 2014; 5:606. [PMID: 25506347 PMCID: PMC4246468 DOI: 10.3389/fpls.2014.00606] [Citation(s) in RCA: 231] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 10/17/2014] [Indexed: 05/18/2023]
Abstract
Plant immunity is often triggered by the specific recognition of pathogen effectors by intracellular nucleotide-binding, leucine-rich repeat receptors (NLR). Plant NLRs contain an N-terminal signaling domain that is mostly represented by either a Toll-interleukin1 receptor (TIR) domain or a coiled coil (CC) domain. In many cases, single NLR proteins are sufficient for both effector recognition and signaling activation. However, many paired NLRs have now been identified where both proteins are required to confer resistance to pathogens. Recent detailed studies on the Arabidopsis thaliana TIR-NLR pair RRS1 and RPS4 and on the rice CC-NLR pair RGA4 and RGA5 have revealed for the first time how such protein pairs function together. In both cases, the paired partners interact physically to form a hetero-complex receptor in which each partner plays distinct roles in effector recognition or signaling activation, highlighting a conserved mode of action of NLR pairs across both monocotyledonous and dicotyledonous plants. We also describe an "integrated decoy" model for the function of these receptor complexes. In this model, a plant protein targeted by an effector has been duplicated and fused to one member of the NLR pair, where it acts as a bait to trigger defense signaling by the second NLR upon effector binding. This mechanism may be common to many other plant NLR pairs.
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Affiliation(s)
- Stella Cesari
- Institut National de la Recherche Agronomique, Unité Mixtes de Recherche Biology and Genetics of Plant-Pathogen InteractionsMontpellier, France
- Centre de Coopération Internationale en Recherche Agronomique pour le Développement, Unité Mixtes de Recherche Biology and Genetics of Plant-Pathogen InteractionsMontpellier, France
- Agriculture Flagship, Commonwealth Scientific and Industrial Research OrganisationCanberra, ACT, Australia
| | - Maud Bernoux
- Agriculture Flagship, Commonwealth Scientific and Industrial Research OrganisationCanberra, ACT, Australia
| | - Philippe Moncuquet
- Commonwealth Scientific and Industrial Research Organisation, Digital Productivity and ServiceCanberra, ACT, Australia
| | - Thomas Kroj
- Institut National de la Recherche Agronomique, Unité Mixtes de Recherche Biology and Genetics of Plant-Pathogen InteractionsMontpellier, France
- Centre de Coopération Internationale en Recherche Agronomique pour le Développement, Unité Mixtes de Recherche Biology and Genetics of Plant-Pathogen InteractionsMontpellier, France
- *Correspondence: Thomas Kroj, Institut National de la Recherche Agronomique, Unité Mixtes de Recherche Biology and Genetics of Plant-Pathogen Interactions, TA A-54/K, Campus International de Baillarguet, 34398 Montpellier, France e-mail:
| | - Peter N. Dodds
- Agriculture Flagship, Commonwealth Scientific and Industrial Research OrganisationCanberra, ACT, Australia
- Peter N. Dodds, CSIRO Agriculture, Clunies Ross Street, GPO Box 1600, Canberra, ACT 2601, Australia e-mail:
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Wan L, Zhang X, Williams SJ, Ve T, Bernoux M, Sohn KH, Jones JDG, Dodds PN, Kobe B. Crystallization and preliminary X-ray diffraction analyses of the TIR domains of three TIR-NB-LRR proteins that are involved in disease resistance in Arabidopsis thaliana. Acta Crystallogr Sect F Struct Biol Cryst Commun 2013; 69:1275-80. [PMID: 24192368 PMCID: PMC3818052 DOI: 10.1107/s1744309113026614] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2013] [Accepted: 09/26/2013] [Indexed: 05/27/2023]
Abstract
The Toll/interleukin-1 receptor (TIR) domain is a protein-protein interaction domain that is found in both animal and plant immune receptors. The N-terminal TIR domain from the nucleotide-binding (NB)-leucine-rich repeat (LRR) class of plant disease-resistance (R) proteins has been shown to play an important role in defence signalling. Recently, the crystal structure of the TIR domain from flax R protein L6 was determined and this structure, combined with functional studies, demonstrated that TIR-domain homodimerization is a requirement for function of the R protein L6. To advance the molecular understanding of the function of TIR domains in R-protein signalling, the protein expression, purification, crystallization and X-ray diffraction analyses of the TIR domains of the Arabidopsis thaliana R proteins RPS4 (resistance to Pseudomonas syringae 4) and RRS1 (resistance to Ralstonia solanacearum 1) and the resistance-like protein SNC1 (suppressor of npr1-1, constitutive 1) are reported here. RPS4 and RRS1 function cooperatively as a dual resistance-protein system that prevents infection by three distinct pathogens. SNC1 is implicated in resistance pathways in Arabidopsis and is believed to be involved in transcriptional regulation through its interaction with the transcriptional corepressor TPR1 (Topless-related 1). The TIR domains of all three proteins have successfully been expressed and purified as soluble proteins in Escherichia coli. Plate-like crystals of the RPS4 TIR domain were obtained using PEG 3350 as a precipitant; they diffracted X-rays to 2.05 Å resolution, had the symmetry of space group P1 and analysis of the Matthews coefficient suggested that there were four molecules per asymmetric unit. Tetragonal crystals of the RRS1 TIR domain were obtained using ammonium sulfate as a precipitant; they diffracted X-rays to 1.75 Å resolution, had the symmetry of space group P4(1)2(1)2 or P4(3)2(1)2 and were most likely to contain one molecule per asymmetric unit. Crystals of the SNC1 TIR domain were obtained using PEG 3350 as a precipitant; they diffracted X-rays to 2.20 Å resolution and had the symmetry of space group P4(1)2(1)2 or P4(3)2(1)2, with two molecules predicted per asymmetric unit. These results provide a good foundation to advance the molecular and structural understanding of the function of the TIR domain in plant innate immunity.
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Affiliation(s)
- Li Wan
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience (Division of Chemistry and Structural Biology) and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, QLD 4072, Australia
| | - Xiaoxiao Zhang
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience (Division of Chemistry and Structural Biology) and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, QLD 4072, Australia
| | - Simon J. Williams
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience (Division of Chemistry and Structural Biology) and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, QLD 4072, Australia
| | - Thomas Ve
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience (Division of Chemistry and Structural Biology) and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, QLD 4072, Australia
| | - Maud Bernoux
- CSIRO Plant Industry, Canberra, ACT 2601, Australia
| | - Kee Hoon Sohn
- The Sainsbury Laboratory, Norwich Research Park, Norwich NR4 7UH, England
| | | | | | - Bostjan Kobe
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience (Division of Chemistry and Structural Biology) and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, QLD 4072, Australia
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Junior CC, Goulart RS, Albertini TZ, Feigl BJ, Cerri CEP, Vasconcelos JT, Bernoux M, D. Lanna DP, Cerri CC. Brazilian beef cattle feedlot manure management: A country survey1. J Anim Sci 2013; 91:1811-8. [DOI: 10.2527/jas.2012-5603] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- C. Costa Junior
- Laboratory of Biogeochemistry, Center of Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, CEP 13416-000 Brazil
| | - R. S. Goulart
- Merck Animal Health, São Paulo, CEP 04794-000 Brazil
| | - T. Z. Albertini
- Laboratory of Computational Mathematics, Embrapa Agriculture Informatics, Campinas, CEP 13083-886 Brazil
| | - B. J. Feigl
- Laboratory of Biogeochemistry, Center of Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, CEP 13416-000 Brazil
| | - C. E. P. Cerri
- Department of Soil Science, Luiz de Queiroz College of Agriculture, University of São Paulo, Piracicaba, CEP 13418-900 Brazil
| | | | - M. Bernoux
- UMR Eco & Sols, Institut de Recherche pour le Développement, Montpellier, 34060 France
| | - D. P. D. Lanna
- Department of Animal Production, Luiz de Queiroz College of Agriculture, University of São Paulo, Piracicaba, CEP 13418-900 Brazil
| | - C. C. Cerri
- Laboratory of Biogeochemistry, Center of Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, CEP 13416-000 Brazil
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Takemoto D, Rafiqi M, Hurley U, Lawrence GJ, Bernoux M, Hardham AR, Ellis JG, Dodds PN, Jones DA. N-terminal motifs in some plant disease resistance proteins function in membrane attachment and contribute to disease resistance. Mol Plant Microbe Interact 2012; 25:379-92. [PMID: 22046960 DOI: 10.1094/mpmi-11-10-0272] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
To investigate the role of N-terminal domains of plant disease resistance proteins in membrane targeting, the N termini of a number of Arabidopsis and flax disease resistance proteins were fused to green fluorescent protein (GFP) and the fusion proteins localized in planta using confocal microscopy. The N termini of the Arabidopsis RPP1-WsB and RPS5 resistance proteins and the PBS1 protein, which is required for RPS5 resistance, targeted GFP to the plasma membrane, and mutation of predicted myristoylation and potential palmitoylation sites resulted in a shift to nucleocytosolic localization. The N-terminal domain of the membrane-attached Arabidopsis RPS2 resistance protein was targeted incompletely to the plasma membrane. In contrast, the N-terminal domains of the Arabidopsis RPP1-WsA and flax L6 and M resistance proteins, which carry predicted signal anchors, were targeted to the endomembrane system, RPP1-WsA to the endoplasmic reticulum and the Golgi apparatus, L6 to the Golgi apparatus, and M to the tonoplast. Full-length L6 was also targeted to the Golgi apparatus. Site-directed mutagenesis of six nonconserved amino acid residues in the signal anchor domains of L6 and M was used to change the localization of the L6 N-terminal fusion protein to that of M and vice versa, showing that these residues control the targeting specificity of the signal anchor. Replacement of the signal anchor domain of L6 by that of M did not affect L6 protein accumulation or resistance against flax rust expressing AvrL567 but removal of the signal anchor domain reduced L6 protein accumulation and L6 resistance, suggesting that membrane attachment is required to stabilize the L6 protein.
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Affiliation(s)
- Daigo Takemoto
- Plant Science Division, Reearch School of Biology, The Australian National University, Canberra ACT 0200, Australia
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Bernoux M, Ellis JG, Dodds PN. New insights in plant immunity signaling activation. Curr Opin Plant Biol 2011; 14:512-8. [PMID: 21723182 PMCID: PMC3191233 DOI: 10.1016/j.pbi.2011.05.005] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2011] [Revised: 05/17/2011] [Accepted: 05/26/2011] [Indexed: 05/19/2023]
Abstract
Plant disease resistance can be triggered by specific recognition of microbial effectors by plant nucleotide binding-leucine rich repeat (NB-LRR) receptors. Over the last few years, many efforts have greatly improved the understanding of effector and NB-LRR function, but have left a lot of questions as to how effector perception activates NB-LRR induction of defense signaling. This review describes exciting new findings showing similarities and differences in function of diverse plant NB-LRR proteins in terms of pathogen recognition and where and how resistance proteins are activated. Localization studies have shown that some NB-LRRs can activate signaling from the cytosol while others act in the nucleus. Also, the structural determination of two NB-LRR signaling domains demonstrated that receptor oligomerization is fundamental for the activation of resistance signaling.
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Affiliation(s)
- Maud Bernoux
- CSIRO Plant Industry, Canberra, Australian Capital Territory 2601, Australia
| | - Jeffrey G. Ellis
- CSIRO Plant Industry, Canberra, Australian Capital Territory 2601, Australia
| | - Peter N. Dodds
- CSIRO Plant Industry, Canberra, Australian Capital Territory 2601, Australia
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Ve T, Williams S, Valkov E, Stamp A, Bernoux M, Hatters D, Ellis JG, Dodds PN, Kobe B. Structural basis of disease resistance in flax against flax rust. Acta Crystallogr A 2011. [DOI: 10.1107/s0108767311097091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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22
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Bernoux M, Ve T, Williams S, Warren C, Hatters D, Valkov E, Zhang X, Ellis JG, Kobe B, Dodds PN. Structural and functional analysis of a plant resistance protein TIR domain reveals interfaces for self-association, signaling, and autoregulation. Cell Host Microbe 2011; 9:200-211. [PMID: 21402359 DOI: 10.1016/j.chom.2011.02.009] [Citation(s) in RCA: 238] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2010] [Revised: 12/21/2010] [Accepted: 02/07/2011] [Indexed: 12/23/2022]
Abstract
The Toll/interleukin-1 receptor (TIR) domain occurs in animal and plant immune receptors. In the animal Toll-like receptors, homodimerization of the intracellular TIR domain is required for initiation of signaling cascades leading to innate immunity. By contrast, the role of the TIR domain in cytoplasmic nucleotide-binding/leucine-rich repeat (NB-LRR) plant immune resistance proteins is poorly understood. L6 is a TIR-NB-LRR resistance protein from flax (Linum usitatissimum) that confers resistance to the flax rust phytopathogenic fungus (Melampsora lini). We determine the crystal structure of the L6 TIR domain and show that, although dispensable for pathogenic effector protein recognition, the TIR domain alone is both necessary and sufficient for L6 immune signaling. We demonstrate that the L6 TIR domain self-associates, most likely forming a homodimer. Analysis of the structure combined with site-directed mutagenesis suggests that self-association is a requirement for immune signaling and reveals distinct surface regions involved in self-association, signaling, and autoregulation.
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Affiliation(s)
- Maud Bernoux
- CSIRO Plant Industry, Canberra, Australian Capital Territory 2601, Australia
| | - Thomas Ve
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience, Division of Chemistry and Structural Biology, University of Queensland, Brisbane, Queensland 4072, Australia; Centre for Infectious Disease Research, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Simon Williams
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience, Division of Chemistry and Structural Biology, University of Queensland, Brisbane, Queensland 4072, Australia; Centre for Infectious Disease Research, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Christopher Warren
- CSIRO Plant Industry, Canberra, Australian Capital Territory 2601, Australia
| | - Danny Hatters
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Eugene Valkov
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience, Division of Chemistry and Structural Biology, University of Queensland, Brisbane, Queensland 4072, Australia; Centre for Infectious Disease Research, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Xiaoxiao Zhang
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience, Division of Chemistry and Structural Biology, University of Queensland, Brisbane, Queensland 4072, Australia; Centre for Infectious Disease Research, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Jeffrey G Ellis
- CSIRO Plant Industry, Canberra, Australian Capital Territory 2601, Australia
| | - Bostjan Kobe
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience, Division of Chemistry and Structural Biology, University of Queensland, Brisbane, Queensland 4072, Australia; Centre for Infectious Disease Research, University of Queensland, Brisbane, Queensland 4072, Australia.
| | - Peter N Dodds
- CSIRO Plant Industry, Canberra, Australian Capital Territory 2601, Australia.
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Tasset C, Bernoux M, Jauneau A, Pouzet C, Brière C, Kieffer-Jacquinod S, Rivas S, Marco Y, Deslandes L. Autoacetylation of the Ralstonia solanacearum effector PopP2 targets a lysine residue essential for RRS1-R-mediated immunity in Arabidopsis. PLoS Pathog 2010; 6:e1001202. [PMID: 21124938 PMCID: PMC2987829 DOI: 10.1371/journal.ppat.1001202] [Citation(s) in RCA: 137] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2010] [Accepted: 10/21/2010] [Indexed: 12/23/2022] Open
Abstract
Type III effector proteins from bacterial pathogens manipulate components of host immunity to suppress defence responses and promote pathogen development. In plants, host proteins targeted by some effectors called avirulence proteins are surveyed by plant disease resistance proteins referred to as “guards”. The Ralstonia solanacearum effector protein PopP2 triggers immunity in Arabidopsis following its perception by the RRS1-R resistance protein. Here, we show that PopP2 interacts with RRS1-R in the nucleus of living plant cells. PopP2 belongs to the YopJ-like family of cysteine proteases, which share a conserved catalytic triad that includes a highly conserved cysteine residue. The catalytic cysteine mutant PopP2-C321A is impaired in its avirulence activity although it is still able to interact with RRS1-R. In addition, PopP2 prevents proteasomal degradation of RRS1-R, independent of the presence of an integral PopP2 catalytic core. A liquid chromatography/tandem mass spectrometry analysis showed that PopP2 displays acetyl-transferase activity leading to its autoacetylation on a particular lysine residue, which is well conserved among all members of the YopJ family. These data suggest that this lysine residue may correspond to a key binding site for acetyl-coenzyme A required for protein activity. Indeed, mutation of this lysine in PopP2 abolishes RRS1-R-mediated immunity. In agreement with the guard hypothesis, our results favour the idea that activation of the plant immune response by RRS1-R depends not only on the physical interaction between the two proteins but also on its perception of PopP2 enzymatic activity. Plant and animal bacterial pathogens have evolved to produce virulence factors, called type III effectors, which are injected into host cells to suppress host defences and provide an environment beneficial for pathogen growth. Type III effectors from pathogenic bacteria display enzymatic activities, often mimicking an endogenous eukaryotic activity, to target host signalling pathways. Elucidation of strategies used by pathogens to manipulate host protein activities is a subject of fundamental interest in pathology. PopP2 is a YopJ-like effector from the soil borne root pathogen Ralstonia solanacearum. Here, in addition to demonstrating PopP2 ability to stabilize the expression of its cognate Arabidopsis RRS1-R resistance protein and physically interact with it, we investigated the enzymatic activity of PopP2. Bacterial YopJ-like effectors are predicted to act as acetyl-transferases on host components. However, only two YopJ-like proteins from animal pathogens have been shown to be active acetyl-transferases. We show that PopP2 displays autoacetyl-transferase activity targeting a lysine residue well-conserved among YopJ-like family members. This lysine is a critical residue since its mutation prevents autoacetylation of PopP2 and abolishes its recognition by the host. This study provides new clues on the multiple properties displayed by bacterial type III effectors that may be used to target defense-related host components.
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Affiliation(s)
- Céline Tasset
- Laboratoire des Interactions Plantes Microorganismes (LIPM), UMR CNRS-INRA 2594/441, Castanet-Tolosan, France
| | - Maud Bernoux
- Laboratoire des Interactions Plantes Microorganismes (LIPM), UMR CNRS-INRA 2594/441, Castanet-Tolosan, France
| | - Alain Jauneau
- Institut Fédératif de Recherche 40, Plateforme Imagerie, Pôle de Biotechnologie Végétale, Castanet-Tolosan, France
| | - Cécile Pouzet
- Institut Fédératif de Recherche 40, Plateforme Imagerie, Pôle de Biotechnologie Végétale, Castanet-Tolosan, France
| | - Christian Brière
- Surfaces Cellulaires et Signalisation chez les Végétaux, Université de Toulouse, UMR CNRS-Université Paul Sabatier 5546, Castanet-Tolosan, France
| | | | - Susana Rivas
- Laboratoire des Interactions Plantes Microorganismes (LIPM), UMR CNRS-INRA 2594/441, Castanet-Tolosan, France
| | - Yves Marco
- Laboratoire des Interactions Plantes Microorganismes (LIPM), UMR CNRS-INRA 2594/441, Castanet-Tolosan, France
| | - Laurent Deslandes
- Laboratoire des Interactions Plantes Microorganismes (LIPM), UMR CNRS-INRA 2594/441, Castanet-Tolosan, France
- * E-mail:
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Rafiqi M, Bernoux M, Ellis JG, Dodds PN. In the trenches of plant pathogen recognition: Role of NB-LRR proteins. Semin Cell Dev Biol 2009; 20:1017-24. [PMID: 19398031 DOI: 10.1016/j.semcdb.2009.04.010] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2009] [Revised: 04/17/2009] [Accepted: 04/17/2009] [Indexed: 01/05/2023]
Abstract
As in nearly every discipline of plant biology, new insights are constantly changing our understanding of plant immunity. It is now clear that plant immunity is controlled by two layers of inducible responses: basal responses triggered by conserved microbial features and specific responses triggered by gene-for-gene recognition of pathogen effector proteins by host resistance (R) proteins. The nucleotide-binding domain leucine-rich repeat (NB-LRR) class of R proteins plays a major role in the combat against a wide range of plant pathogens. The variation that has been generated and is maintained within these conserved proteins has diversified their specificity, subcellular localisations, activation and recognition mechanisms, allowing them to specifically adapt to different plant-pathogen interaction systems. This review addresses recent advances in the molecular role of NB-LRR proteins in pathogen recognition and activation of plant defence responses.
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Affiliation(s)
- Maryam Rafiqi
- Plant Cell Biology Group, Research School of Biological Sciences, Australian National University, Canberra, ACT 2601, Australia.
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Bernoux M, Timmers T, Jauneau A, Brière C, de Wit PJGM, Marco Y, Deslandes L. RD19, an Arabidopsis cysteine protease required for RRS1-R-mediated resistance, is relocalized to the nucleus by the Ralstonia solanacearum PopP2 effector. Plant Cell 2008; 20:2252-64. [PMID: 18708476 PMCID: PMC2553607 DOI: 10.1105/tpc.108.058685] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2008] [Revised: 07/18/2008] [Accepted: 07/31/2008] [Indexed: 05/18/2023]
Abstract
Bacterial wilt, a disease impacting cultivated crops worldwide, is caused by the pathogenic bacterium Ralstonia solanacearum. PopP2 (for Pseudomonas outer protein P2) is an R. solanacearum type III effector that belongs to the YopJ/AvrRxv protein family and interacts with the Arabidopsis thaliana RESISTANT TO RALSTONIA SOLANACEARUM 1-R (RRS1-R) resistance protein. RRS1-R contains the Toll/Interleukin1 receptor-nucleotide binding site-Leu-rich repeat domains found in several cytoplasmic R proteins and a C-terminal WRKY DNA binding domain. In this study, we identified the Arabidopsis Cys protease RESPONSIVE TO DEHYDRATION19 (RD19) as being a PopP2-interacting protein whose expression is induced during infection by R. solanacearum. An Arabidopsis rd19 mutant in an RRS1-R genetic background is compromised in resistance to the bacterium, indicating that RD19 is required for RRS1-R-mediated resistance. RD19 normally localizes in mobile vacuole-associated compartments and, upon coexpression with PopP2, is specifically relocalized to the plant nucleus, where the two proteins physically interact. No direct physical interaction between RRS1-R and RD19 in the presence of PopP2 was detected in the nucleus as determined by Förster resonance energy transfer. We propose that RD19 associates with PopP2 to form a nuclear complex that is required for activation of the RRS1-R-mediated resistance response.
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Affiliation(s)
- Maud Bernoux
- Laboratoire des Interactions Plantes Microorganismes, Unité Mixte de Recherche, Centre National de la Recherche Scientifique-Institut National de la Recherche Agronomique 2594/441, F-31320 Castanet-Tolosan, France
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Bernoux M, Timmers T, Jauneau A, Brière C, de Wit PJGM, Marco Y, Deslandes L. RD19, an Arabidopsis cysteine protease required for RRS1-R-mediated resistance, is relocalized to the nucleus by the Ralstonia solanacearum PopP2 effector. Plant Cell 2008; 20:2252-2264. [PMID: 18708476 DOI: 10.2307/25224327] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Bacterial wilt, a disease impacting cultivated crops worldwide, is caused by the pathogenic bacterium Ralstonia solanacearum. PopP2 (for Pseudomonas outer protein P2) is an R. solanacearum type III effector that belongs to the YopJ/AvrRxv protein family and interacts with the Arabidopsis thaliana RESISTANT TO RALSTONIA SOLANACEARUM 1-R (RRS1-R) resistance protein. RRS1-R contains the Toll/Interleukin1 receptor-nucleotide binding site-Leu-rich repeat domains found in several cytoplasmic R proteins and a C-terminal WRKY DNA binding domain. In this study, we identified the Arabidopsis Cys protease RESPONSIVE TO DEHYDRATION19 (RD19) as being a PopP2-interacting protein whose expression is induced during infection by R. solanacearum. An Arabidopsis rd19 mutant in an RRS1-R genetic background is compromised in resistance to the bacterium, indicating that RD19 is required for RRS1-R-mediated resistance. RD19 normally localizes in mobile vacuole-associated compartments and, upon coexpression with PopP2, is specifically relocalized to the plant nucleus, where the two proteins physically interact. No direct physical interaction between RRS1-R and RD19 in the presence of PopP2 was detected in the nucleus as determined by Förster resonance energy transfer. We propose that RD19 associates with PopP2 to form a nuclear complex that is required for activation of the RRS1-R-mediated resistance response.
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Affiliation(s)
- Maud Bernoux
- Laboratoire des Interactions Plantes Microorganismes, Unité Mixte de Recherche, Centre National de la Recherche Scientifique-Institut National de la Recherche Agronomique 2594/441, F-31320 Castanet-Tolosan, France
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Feller C, Bernoux M. Historical advances in the study of global terrestrial soil organic carbon sequestration. Waste Manag 2007; 28:734-740. [PMID: 18032016 DOI: 10.1016/j.wasman.2007.09.022] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2007] [Accepted: 09/06/2007] [Indexed: 05/25/2023]
Abstract
This paper serves two purposes: it provides a summarized scientific history of carbon sequestration in relation to the soil-plant system and gives a commentary on organic wastes and SOC sequestration. The concept of soil organic carbon (SOC) sequestration has its roots in: (i) the experimental work of Lundegårdh, particularly his in situ measurements of CO2 fluxes at the soil-plant interface (1924, 1927, 1930); (ii) the first estimates of SOC stocks at the global level made by Waksman [Waksman, S.A., 1938. Humus. Origin, Chemical Composition and Importance in Nature, second ed. revised. Williams and Wilkins, Baltimore, p. 526] and Rubey [Rubey, W.W., 1951. Geologic history of sea water. Bulletin of the Geological Society of America 62, 1111-1148]; (iii) the need for models dealing with soil organic matter (SOM) or SOC dynamics beginning with a conceptual SOM model by De Saussure (1780-1796) followed by the mathematical models of Jenny [Jenny, H., 1941. Factors of Soil Formation: a System of Quantitative Pedology. Dover Publications, New York, p. 288], Hénin and Dupuis [Hénin, S., Dupuis, M., 1945. Essai de bilan de la matière organique. Annales d'Agronomie 15, 17-29] and more recently the RothC [Jenkinson, D.S., Rayner, J.H., 1977. The turnover of soil organic matter in some of the Rothamsted classical experiments. Soil Science 123 (5), 298-305] and Century [Parton, W.J., Schimel, D.S., Cole, C.V., Ojima, D.S., 1987. Analysis of factors controlling soil organic matter levels in great plains grasslands. Soil Science Society of America Journal 51 (5), 1173-1179] models. The establishment of a soil C sequestration balance is not straightforward and depends greatly on the origin and the composition of organic matter that is to be returned to the system. Wastes, which are important sources of organic carbon for soils, are taken as an example. For these organic materials the following factors have to be considered: the presence or absence of fossil C, the potential of direct and indirect emissions of non-CO2 greenhouse gases (CH4 and N2O) following application and the agro-system which is being used as a comparative reference.
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Affiliation(s)
- C Feller
- Institut de Recherche pour le Développement (IRD), UR SeqBio, ENSAM, 2 Place Viala, 34060 Montpellier cedex 1, France.
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