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Liu Y, Chen Y, Li B, Jing Y, Tian S, Chen T. Revisiting Endoplasmic Reticulum Homeostasis, an Expanding Frontier Between Host Plants and Pathogens. PLANT, CELL & ENVIRONMENT 2025; 48:3281-3292. [PMID: 39722546 DOI: 10.1111/pce.15344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2024] [Revised: 12/05/2024] [Accepted: 12/10/2024] [Indexed: 12/28/2024]
Abstract
The endoplasmic reticulum (ER) serves as the primary site for protein biosynthesis and processing, with ER homeostasis being essential for the survival of plant cells. Numerous studies have underscored the pivotal role of the ER as a battleground for host-pathogen interactions. Pathogens secrete effectors to subvert the host ER and manipulate ER-mediated defense responses, fostering an infection-permissive environment for their proliferation. Plants respond to these challenges by triggering ER stress responses, including the unfolded protein response (UPR), autophagy, and cell death pathways, to combat pathogens and ensure survival. Consequently, plants are faced with a life-or-death decision, directly influencing the outcomes of pathogen infection. In this review, recent advances in manipulating host ER homeostasis by pathogens are introduced, further key counteracting strategies employed by host plants to maintain ER homeostasis during infection are summarized, and finally, several pending questions the studies involving both parties in this evolving field are proposed.
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Affiliation(s)
- Yuhan Liu
- State Key Laboratory of Plant Diversity and Specialty Crops, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- China National Botanical Garden, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yong Chen
- State Key Laboratory of Plant Diversity and Specialty Crops, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- China National Botanical Garden, Beijing, China
| | - Boqiang Li
- State Key Laboratory of Plant Diversity and Specialty Crops, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- China National Botanical Garden, Beijing, China
| | - Yanping Jing
- College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
| | - Shiping Tian
- State Key Laboratory of Plant Diversity and Specialty Crops, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- China National Botanical Garden, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Tong Chen
- State Key Laboratory of Plant Diversity and Specialty Crops, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- China National Botanical Garden, Beijing, China
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Qu J, Liu L, Zheng C, Guo Z, Sun D, Pan F, Lu J, Yin L. Plasmopara viticola Effector PvRXLR10 Targets a Host Phospholipase VvipPLA-IIδ2 to Suppress Plant Immunity in Grapevine. MOLECULAR PLANT PATHOLOGY 2025; 26:e70095. [PMID: 40375562 PMCID: PMC12081833 DOI: 10.1111/mpp.70095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2024] [Revised: 04/15/2025] [Accepted: 05/01/2025] [Indexed: 05/18/2025]
Abstract
Plasmopara viticola that causes grapevine downy mildew disease in viticulture regions is among the 10 most relevant pathogens worldwide. It secretes a large arsenal of effectors to facilitate colonisation by perturbing host immunity. However, the underlying mechanisms by which P. viticola effectors disturb grapevine defence are still largely unknown. In this study, we report that PvRXLR10, an RXLR effector with a WY domain, promotes P. viticola infection in grapevine and Phytophthora parasitica colonisation in Nicotiana benthamiana. PvRXLR10 interacts with a host patatin-like protein VvipPLA-IIδ2 with phospholipase A2 activity. The WY domain of PvRXLR10 is not responsible for cell death suppression in N. benthamiana but is necessary for PvRXLR10 interaction with VvipPLA-IIδ2. Overexpression and RNAi-mediated suppression of VvipPLA-IIδ2 expression in Vitis vinifera consistently showed that this protein positively regulates plant immunity in response to P. viticola infection. Interestingly, we found that VvipPLA-IIδ2 partially associates with PvRXLR10 at the endoplasmic reticulum (ER). Reverse transcription-quantitative PCR (RT-qPCR) analysis showed that the expression of VvipPLA-IIδ2 was suppressed by PvRXLR10 during P. viticola infection. The overexpression of VvipPLA-IIδ2 in V. vinifera induced higher expression of genes related to jasmonic acid (JA) biosynthesis, signalling pathways and defence response. The evidence indicates the important roles of VvipPLA-IIδ2 in grapevine immunity and P. viticola effector PvRXLR10 targets this protein to promote its infection.
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Affiliation(s)
- Junjie Qu
- Guangxi Crop Genetic Improvement and Biotechnology Key LabGuangxi Academy of Agricultural SciencesNanningChina
| | - Lulu Liu
- Guangxi Crop Genetic Improvement and Biotechnology Key LabGuangxi Academy of Agricultural SciencesNanningChina
| | - Chengxu Zheng
- Guangxi Crop Genetic Improvement and Biotechnology Key LabGuangxi Academy of Agricultural SciencesNanningChina
| | - Zexi Guo
- Guangxi Crop Genetic Improvement and Biotechnology Key LabGuangxi Academy of Agricultural SciencesNanningChina
| | - Dayun Sun
- Guangxi Crop Genetic Improvement and Biotechnology Key LabGuangxi Academy of Agricultural SciencesNanningChina
| | - Fengying Pan
- Guangxi Crop Genetic Improvement and Biotechnology Key LabGuangxi Academy of Agricultural SciencesNanningChina
| | - Jiang Lu
- Center for Viticulture and Enology, School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghaiChina
| | - Ling Yin
- Guangxi Crop Genetic Improvement and Biotechnology Key LabGuangxi Academy of Agricultural SciencesNanningChina
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3
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Maul JE, Lydon J, Lakshman D, Willard C, Kong H, Roberts DP. Genomic and mutational analysis of Pseudomonas syringae pv. tagetis EB037 pathogenicity on sunflower. BMC Microbiol 2025; 25:43. [PMID: 39856564 PMCID: PMC11760712 DOI: 10.1186/s12866-024-03685-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2024] [Accepted: 12/03/2024] [Indexed: 01/27/2025] Open
Abstract
BACKGROUND Pseudomonas syringae pv. tagetis (Pstag) causes apical chlorosis on sunflower and various other plants of the Asteraceae family. Whole genome sequencing of Pstag strain EB037 and transposon-mutant derivatives, no longer capable of causing apical chlorosis, was conducted to improve understanding of the molecular basis of disease caused by this pathogen. RESULTS A tripartite pathogenicity island (TPI) for a Type III secretion system (T3SS) with the complete hrp-hrc gene cluster and conserved effector locus was detected in the Pstag genome. The exchange effector region of the TPI contained genes potentially functioning in detoxification of the environment as well as two integrases, but no previously described T3SS effector homologues. In all, the Pstag EB037 genome contained homologues for at least 44 T3SS effectors with 30 having known functions. Plasmids similar with pTagA and pTagB of P. syringae pv. tagetis ICMP 4091 were also identified in the Pstag genome. The pTagA-like plasmid contained a complete Type IV secretion system (T4SS) with associated putative killer protein. Mutational analysis using transposon insertions within genes functioning in the T3SS and T4SS confirmed the role of both secretion systems and these plasmids in apical chlorosis. Transposon mutagenesis identified an additional 22 genes in loci, including two more plasmid-bound loci, involved in apical chlorosis on sunflower; some with known importance in other plant or animal pathosystems. CONCLUSIONS Apical chlorosis disease caused by Pstag EB037 is the result of a complex set of mechanisms. This study identified a TPI and homologues for at least 44 T3SS effectors, 30 of which with known functions in disease, and another 20 genes in loci correlated with apical chlorosis on sunflower. Two plasmids were detected that were correlated with apical chlorosis disease, one of which contained a complete T4SS that was correlated with disease. To our knowledge, we provide the first direct evidence for a T4SS functioning in disease by a pathogenic P. syringae strain.
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Affiliation(s)
- Jude E Maul
- USDA-ARS, Sustainable Agricultural Systems Laboratory, Beltsville Agricultural Research Center, Beltsville, MD, 20705, USA
| | - John Lydon
- USDA-ARS, Sustainable Agricultural Systems Laboratory, Beltsville Agricultural Research Center, Beltsville, MD, 20705, USA
| | - Dilip Lakshman
- USDA-ARS, Sustainable Agricultural Systems Laboratory, Beltsville Agricultural Research Center, Beltsville, MD, 20705, USA
| | - Colin Willard
- USDA-ARS, Sustainable Agricultural Systems Laboratory, Beltsville Agricultural Research Center, Beltsville, MD, 20705, USA
| | - Hyesuk Kong
- USDA-ARS, Sustainable Agricultural Systems Laboratory, Beltsville Agricultural Research Center, Beltsville, MD, 20705, USA
- Present Address: Food and Drug Administration, Center for Biologics Evaluation and Research, Silver Spring, Beltsville, MD, 20993, USA
| | - Daniel P Roberts
- USDA-ARS, Sustainable Agricultural Systems Laboratory, Beltsville Agricultural Research Center, Beltsville, MD, 20705, USA.
- USDA-ARS, Office of National Programs, George Washington Carver Center, Beltsville, MD, 20705, USA.
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Chadha S, Menendez E, Montes N. Editorial: Women in microbe and virus interactions with plants: 2022/2023. Front Microbiol 2025; 15:1532112. [PMID: 39850136 PMCID: PMC11754181 DOI: 10.3389/fmicb.2024.1532112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2024] [Accepted: 12/02/2024] [Indexed: 01/25/2025] Open
Affiliation(s)
- Sonia Chadha
- Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Centre, Mumbai, India
- Homi Bhabha National Institute, Mumbai, India
| | - Esther Menendez
- Departamento de Microbiología y Genética, Universidad de Salamanca, Salamanca, Spain
- Institute for Agrobiotechnology Research (CIALE), Salamanca, Spain
- Unidad Asociada Grupo de Interacción Planta-Microorganismo, Universidad de Salamanca-IRNASA-CSIC, Salamanca, Spain
| | - Nuria Montes
- Servicio de Reumatología, Unidad de Metodología, Instituto de Investigación Sanitaria La Princesa (IIS-IP), Madrid, Spain
- Servicio de Reumatología, Hospital Universitario La Princesa, Madrid, Spain
- Plant Physiology, Pharmaceutical and Health Sciences Department, Faculty of Pharmacy, Universidad San Pablo-CEU, CEU-Universities, Boadilla del Monte, Spain
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Xiang H, Stojilkovic B, Gheysen G. Decoding Plant-Pathogen Interactions: A Comprehensive Exploration of Effector-Plant Transcription Factor Dynamics. MOLECULAR PLANT PATHOLOGY 2025; 26:e70057. [PMID: 39854033 PMCID: PMC11757022 DOI: 10.1111/mpp.70057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2024] [Revised: 01/07/2025] [Accepted: 01/09/2025] [Indexed: 01/26/2025]
Abstract
In the coevolutionary process between plant pathogens and hosts, pathogen effectors, primarily proteinaceous, engage in interactions with host proteins, such as plant transcription factors (TFs), during the infection process. This review delves into the intricate interplay between TFs and effectors, a key aspect in the prolonged and complex battle between plants and pathogens. Effectors strategically manipulate TFs using diverse tactics. These include modulating activity of TFs, influencing their incorporation into multimeric complexes, directly changing TF expression levels, promoting their degradation via the ubiquitin-proteasome system, and inducing their subcellular relocalization. The review systematically presents documented interactions, elucidating key mechanisms and their profound impact on host-pathogen dynamics. It emphasises the central role of TFs in plant defence and investigates the convergent evolution of effectors targeting TFs. By providing this overview, we offer valuable insights into this dynamic interaction landscape and suggest potential directions for future research.
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Affiliation(s)
- Hui Xiang
- Faculty of Bioscience EngineeringGhent UniversityGentBelgium
| | - Boris Stojilkovic
- Faculty of Bioscience EngineeringGhent UniversityGentBelgium
- John Innes CentreNorwichUK
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Dong B, Liu Y, Huang G, Song A, Chen S, Jiang J, Chen F, Fang W. Plant NAC transcription factors in the battle against pathogens. BMC PLANT BIOLOGY 2024; 24:958. [PMID: 39396978 PMCID: PMC11472469 DOI: 10.1186/s12870-024-05636-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2024] [Accepted: 09/25/2024] [Indexed: 10/15/2024]
Abstract
BACKGROUND The NAC transcription factor family, which is recognized as one of the largest plant-specific transcription factor families, comprises numerous members that are widely distributed among various higher plant species and play crucial regulatory roles in plant immunity. RESULTS In this paper, we provided a detailed summary of the roles that NAC transcription factors play in plant immunity via plant hormone pathways and reactive oxygen species pathways. In addition, we conducted in-depth investigations into the interactions between NAC transcription factors and pathogen effectors to summarize the mechanism through which they regulate the expression of defense-related genes and ultimately affect plant disease resistance. CONCLUSIONS This paper presented a comprehensive overview of the crucial roles that NAC transcription factors play in regulating plant disease resistance through their involvement in diverse signaling pathways, acting as either positive or negative regulators, and thus provided references for further research on NAC transcription factors.
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Affiliation(s)
- Boxiao Dong
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs, Key Laboratory of State Forestry and Grassland Administration on Biology of Ornamental Plants in East China, College of Horticulture, Nanjing Agricultural University, No.1 Weigang, Nanjing, 210095, China
| | - Ye Liu
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs, Key Laboratory of State Forestry and Grassland Administration on Biology of Ornamental Plants in East China, College of Horticulture, Nanjing Agricultural University, No.1 Weigang, Nanjing, 210095, China.
- Zhongshan Biological Breeding Laboratory, No.50 Zhongling Street, Nanjing, 210014, Jiangsu, China.
| | - Gan Huang
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs, Key Laboratory of State Forestry and Grassland Administration on Biology of Ornamental Plants in East China, College of Horticulture, Nanjing Agricultural University, No.1 Weigang, Nanjing, 210095, China
| | - Aiping Song
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs, Key Laboratory of State Forestry and Grassland Administration on Biology of Ornamental Plants in East China, College of Horticulture, Nanjing Agricultural University, No.1 Weigang, Nanjing, 210095, China
- Zhongshan Biological Breeding Laboratory, No.50 Zhongling Street, Nanjing, 210014, Jiangsu, China
| | - Sumei Chen
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs, Key Laboratory of State Forestry and Grassland Administration on Biology of Ornamental Plants in East China, College of Horticulture, Nanjing Agricultural University, No.1 Weigang, Nanjing, 210095, China
- Zhongshan Biological Breeding Laboratory, No.50 Zhongling Street, Nanjing, 210014, Jiangsu, China
| | - Jiafu Jiang
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs, Key Laboratory of State Forestry and Grassland Administration on Biology of Ornamental Plants in East China, College of Horticulture, Nanjing Agricultural University, No.1 Weigang, Nanjing, 210095, China
- Zhongshan Biological Breeding Laboratory, No.50 Zhongling Street, Nanjing, 210014, Jiangsu, China
| | - Fadi Chen
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs, Key Laboratory of State Forestry and Grassland Administration on Biology of Ornamental Plants in East China, College of Horticulture, Nanjing Agricultural University, No.1 Weigang, Nanjing, 210095, China
- Zhongshan Biological Breeding Laboratory, No.50 Zhongling Street, Nanjing, 210014, Jiangsu, China
| | - Weimin Fang
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs, Key Laboratory of State Forestry and Grassland Administration on Biology of Ornamental Plants in East China, College of Horticulture, Nanjing Agricultural University, No.1 Weigang, Nanjing, 210095, China.
- Zhongshan Biological Breeding Laboratory, No.50 Zhongling Street, Nanjing, 210014, Jiangsu, China.
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7
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Cervantes-Pérez SA, Zogli P, Amini S, Thibivilliers S, Tennant S, Hossain MS, Xu H, Meyer I, Nooka A, Ma P, Yao Q, Naldrett MJ, Farmer A, Martin O, Bhattacharya S, Kläver J, Libault M. Single-cell transcriptome atlases of soybean root and mature nodule reveal new regulatory programs that control the nodulation process. PLANT COMMUNICATIONS 2024; 5:100984. [PMID: 38845198 PMCID: PMC11369782 DOI: 10.1016/j.xplc.2024.100984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2024] [Revised: 05/21/2024] [Accepted: 06/03/2024] [Indexed: 07/14/2024]
Abstract
The soybean root system is complex. In addition to being composed of various cell types, the soybean root system includes the primary root, the lateral roots, and the nodule, an organ in which mutualistic symbiosis with N-fixing rhizobia occurs. A mature soybean root nodule is characterized by a central infection zone where atmospheric nitrogen is fixed and assimilated by the symbiont, resulting from the close cooperation between the plant cell and the bacteria. To date, the transcriptome of individual cells isolated from developing soybean nodules has been established, but the transcriptomic signatures of cells from the mature soybean nodule have not yet been characterized. Using single-nucleus RNA-seq and Molecular Cartography technologies, we precisely characterized the transcriptomic signature of soybean root and mature nodule cell types and revealed the co-existence of different sub-populations of B. diazoefficiens-infected cells in the mature soybean nodule, including those actively involved in nitrogen fixation and those engaged in senescence. Mining of the single-cell-resolution nodule transcriptome atlas and the associated gene co-expression network confirmed the role of known nodulation-related genes and identified new genes that control the nodulation process. For instance, we functionally characterized the role of GmFWL3, a plasma membrane microdomain-associated protein that controls rhizobial infection. Our study reveals the unique cellular complexity of the mature soybean nodule and helps redefine the concept of cell types when considering the infection zone of the soybean nodule.
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Affiliation(s)
| | - Prince Zogli
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, NE 68503, USA
| | - Sahand Amini
- Division of Plant Science and Technology, College of Agriculture, Food, and Natural Resources, University of Missouri-Columbia, Columbia, MO 65211, USA; Interdisciplinary Plant Group of Missouri-Columbia, Columbia, MO 65211, USA
| | - Sandra Thibivilliers
- Division of Plant Science and Technology, College of Agriculture, Food, and Natural Resources, University of Missouri-Columbia, Columbia, MO 65211, USA; Interdisciplinary Plant Group of Missouri-Columbia, Columbia, MO 65211, USA
| | - Sutton Tennant
- Division of Plant Science and Technology, College of Agriculture, Food, and Natural Resources, University of Missouri-Columbia, Columbia, MO 65211, USA; Interdisciplinary Plant Group of Missouri-Columbia, Columbia, MO 65211, USA
| | - Md Sabbir Hossain
- Division of Plant Science and Technology, College of Agriculture, Food, and Natural Resources, University of Missouri-Columbia, Columbia, MO 65211, USA; Interdisciplinary Plant Group of Missouri-Columbia, Columbia, MO 65211, USA
| | - Hengping Xu
- Division of Plant Science and Technology, College of Agriculture, Food, and Natural Resources, University of Missouri-Columbia, Columbia, MO 65211, USA; Interdisciplinary Plant Group of Missouri-Columbia, Columbia, MO 65211, USA
| | - Ian Meyer
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, NE 68503, USA
| | - Akash Nooka
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, NE 68503, USA
| | - Pengchong Ma
- School of Computing, University of Nebraska-Lincoln, Lincoln, NE 68503, USA
| | - Qiuming Yao
- School of Computing, University of Nebraska-Lincoln, Lincoln, NE 68503, USA
| | - Michael J Naldrett
- Proteomics and Metabolomics Facility, Center for Biotechnology, University of Nebraska-Lincoln, Lincoln, NE 68588, USA
| | - Andrew Farmer
- National Center for Genome Resources, Santa Fe, NM 87505, USA
| | - Olivier Martin
- INRAE, Université Paris-Saclay, Institut des Sciences des Plantes de Paris Saclay, IPS2, Batiment 630 Plateau du Moulon, Rue Noetzlin, 91192 Gif sur Yvette Cedex, France
| | | | | | - Marc Libault
- Division of Plant Science and Technology, College of Agriculture, Food, and Natural Resources, University of Missouri-Columbia, Columbia, MO 65211, USA; Interdisciplinary Plant Group of Missouri-Columbia, Columbia, MO 65211, USA.
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8
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Bhandari DD, Brandizzi F. Logistics of defense: The contribution of endomembranes to plant innate immunity. J Cell Biol 2024; 223:e202307066. [PMID: 38551496 PMCID: PMC10982075 DOI: 10.1083/jcb.202307066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 03/15/2024] [Accepted: 03/18/2024] [Indexed: 04/02/2024] Open
Abstract
Phytopathogens cause plant diseases that threaten food security. Unlike mammals, plants lack an adaptive immune system and rely on their innate immune system to recognize and respond to pathogens. Plant response to a pathogen attack requires precise coordination of intracellular traffic and signaling. Spatial and/or temporal defects in coordinating signals and cargo can lead to detrimental effects on cell development. The role of intracellular traffic comes into a critical focus when the cell sustains biotic stress. In this review, we discuss the current understanding of the post-immune activation logistics of plant defense. Specifically, we focus on packaging and shipping of defense-related cargo, rerouting of intracellular traffic, the players enabling defense-related traffic, and pathogen-mediated subversion of these pathways. We highlight the roles of the cytoskeleton, cytoskeleton-organelle bridging proteins, and secretory vesicles in maintaining pathways of exocytic defense, acting as sentinels during pathogen attack, and the necessary elements for building the cell wall as a barrier to pathogens. We also identify points of convergence between mammalian and plant trafficking pathways during defense and highlight plant unique responses to illustrate evolutionary adaptations that plants have undergone to resist biotic stress.
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Affiliation(s)
- Deepak D. Bhandari
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI, USA
- Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI, USA
| | - Federica Brandizzi
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI, USA
- Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI, USA
- Department of Plant Biology, Michigan State University, East Lansing, MI, USA
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Niu MX, Feng CH, He F, Zhang H, Bao Y, Liu SJ, Liu X, Su Y, Liu C, Wang HL, Yin W, Xia X. The miR6445-NAC029 module regulates drought tolerance by regulating the expression of glutathione S-transferase U23 and reactive oxygen species scavenging in Populus. THE NEW PHYTOLOGIST 2024; 242:2043-2058. [PMID: 38515251 DOI: 10.1111/nph.19703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Accepted: 03/06/2024] [Indexed: 03/23/2024]
Abstract
MicroRNAs are essential in plant development and stress resistance, but their specific roles in drought stress require further investigation. Here, we have uncovered that a Populus-specific microRNAs (miRNA), miR6445, targeting NAC (NAM, ATAF, and CUC) family genes, is involved in regulating drought tolerance of poplar. The expression level of miR6445 was significantly upregulated under drought stress; concomitantly, seven targeted NAC genes showed significant downregulation. Silencing the expression of miR6445 by short tandem target mimic technology significantly decreased the drought tolerance in poplar. Furthermore, 5' RACE experiments confirmed that miR6445 directly targeted NAC029. The overexpression lines of PtrNAC029 (OE-NAC029) showed increased sensitivity to drought compared with knockout lines (Crispr-NAC029), consistent with the drought-sensitive phenotype observed in miR6445-silenced strains. PtrNAC029 was further verified to directly bind to the promoters of glutathione S-transferase U23 (GSTU23) and inhibit its expression. Both Crispr-NAC029 and PtrGSTU23 overexpressing plants showed higher levels of PtrGSTU23 transcript and GST activity while accumulating less reactive oxygen species (ROS). Moreover, poplars overexpressing GSTU23 demonstrated enhanced drought tolerance. Taken together, our research reveals the crucial role of the miR6445-NAC029-GSTU23 module in enhancing poplar drought tolerance by regulating ROS homeostasis. This finding provides new molecular targets for improving the drought resistance of trees.
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Affiliation(s)
- Meng-Xue Niu
- State Key Laboratory of Tree Genetics and Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China
| | - Cong-Hua Feng
- State Key Laboratory of Tree Genetics and Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China
| | - Fang He
- Key Laboratory of National Forestry & Grassland Administration on Forest Resources Conservation and Ecological Safety in the Upper Reaches of the Yangtze River, College of Forestry, Sichuan Agricultural University, Chengdu, 611130, China
| | - Han Zhang
- State Key Laboratory of Tree Genetics and Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China
| | - Yu Bao
- State Key Laboratory of Tree Genetics and Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China
| | - Shu-Jing Liu
- State Key Laboratory of Tree Genetics and Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China
| | - Xiao Liu
- State Key Laboratory of Tree Genetics and Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China
| | - Yanyan Su
- State Key Laboratory of Tree Genetics and Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China
| | - Chao Liu
- State Key Laboratory of Tree Genetics and Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China
| | - Hou-Ling Wang
- State Key Laboratory of Tree Genetics and Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China
| | - Weilun Yin
- State Key Laboratory of Tree Genetics and Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China
| | - Xinli Xia
- State Key Laboratory of Tree Genetics and Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China
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10
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Shu L, Li L, Jiang YQ, Yan J. Advances in membrane-tethered NAC transcription factors in plants. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2024; 342:112034. [PMID: 38365003 DOI: 10.1016/j.plantsci.2024.112034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 02/08/2024] [Accepted: 02/11/2024] [Indexed: 02/18/2024]
Abstract
Transcription factors are central components in cell signal transduction networks and are critical regulators for gene expression. It is estimated that approximately 10% of all transcription factors are membrane-tethered. MTFs (membrane-bound transcription factors) are latent transcription factors that are inherently anchored in the cellular membrane in a dormant form. When plants encounter environmental stimuli, they will be released from the membrane by intramembrane proteases or by the ubiquitin proteasome pathway and then were translocated to the nucleus. The capacity to instantly activate dormant transcription factors is a critical strategy for modulating diverse cellular functions in response to external or internal signals, which provides an important transcriptional regulatory network in response to sudden stimulus and improves plant survival. NTLs (NTM1-like) are a small subset of NAC (NAM, ATAF1/2, CUC2) transcription factors, which contain a conserved NAC domain at the N-terminus and a transmembrane domain at the C-terminus. In the past two decades, several NTLs have been identified from several species, and most of them are involved in both development and stress response. In this review, we review the reports and findings on NTLs in plants and highlight the mechanism of their nuclear import as well as their functions in regulating plant growth and stress response.
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Affiliation(s)
- Lin Shu
- College of Plant Protection, Henan Agricultural University, Zhengzhou, Henan province 450002, China
| | - Longhui Li
- College of Plant Protection, Henan Agricultural University, Zhengzhou, Henan province 450002, China
| | - Yuan-Qing Jiang
- State Key Laboratory of Crop Stress Biology for Arid Areas and, College of Life Sciences, Northwest A & F University, Yangling, Shaanxi province 712100, China
| | - Jingli Yan
- College of Plant Protection, Henan Agricultural University, Zhengzhou, Henan province 450002, China.
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11
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Liu J, Fan Y, Liu Y, He M, Sun Y, Zheng Q, Mi L, Liu J, Liu W, Tang N, Zhao X, Hu Z, Guo S, Yan D. APP1/NTL9-CalS8 module ensures proper phloem differentiation by stabilizing callose accumulation and symplastic communication. THE NEW PHYTOLOGIST 2024; 242:154-169. [PMID: 38375601 DOI: 10.1111/nph.19617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Accepted: 02/04/2024] [Indexed: 02/21/2024]
Abstract
Phloem sieve elements (PSE), the primary conduits collaborating with neighboring phloem pole pericycle (PPP) cells to facilitate unloading in Arabidopsis roots, undergo a series of developmental stages before achieving maturation and functionality. However, the mechanism that maintains the proper progression of these differentiation stages remains largely unknown. We identified a gain-of-function mutant altered phloem pole pericycle 1 Dominant (app1D), producing a truncated, nuclear-localized active form of NAC with Transmembrane Motif 1-like (NTL9). This mutation leads to ectopic expression of its downstream target CALLOSE SYNTHASE 8 (CalS8), thereby inducing callose accumulation, impeding SE differentiation, impairing phloem transport, and inhibiting root growth. The app1D phenotype could be reproduced by blocking the symplastic channels of cells within APP1 expression domain in wild-type (WT) roots. The WT APP1 is primarily membrane-tethered and dormant in the root meristem cells but entries into the nucleus in several cells in PPP near the unloading region, and this import is inhibited by blocking the symplastic intercellular transport in differentiating SE. Our results suggest a potential maintenance mechanism involving an APP1-CalS8 module, which induces CalS8 expression and modulates symplastic communication, and the proper activation of this module is crucial for the successful differentiation of SE in the Arabidopsis root.
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Affiliation(s)
- Jie Liu
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Academy for Advanced Interdisciplinary Studies, Henan University, Kaifeng, 475004, China
| | - Yongxiao Fan
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Academy for Advanced Interdisciplinary Studies, Henan University, Kaifeng, 475004, China
| | - Yao Liu
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Academy for Advanced Interdisciplinary Studies, Henan University, Kaifeng, 475004, China
| | - Meiqing He
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Academy for Advanced Interdisciplinary Studies, Henan University, Kaifeng, 475004, China
| | - Yanke Sun
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Academy for Advanced Interdisciplinary Studies, Henan University, Kaifeng, 475004, China
| | - Qi Zheng
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Academy for Advanced Interdisciplinary Studies, Henan University, Kaifeng, 475004, China
| | - Lingyu Mi
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Academy for Advanced Interdisciplinary Studies, Henan University, Kaifeng, 475004, China
| | - Junzhong Liu
- Center for Life Sciences, School of Life Sciences, State Key Laboratory of Conservation and Utilization of Bio-Resources in Yunnan, Yunnan University, Kunming, 650500, China
| | - Wencheng Liu
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Academy for Advanced Interdisciplinary Studies, Henan University, Kaifeng, 475004, China
| | - Ning Tang
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Academy for Advanced Interdisciplinary Studies, Henan University, Kaifeng, 475004, China
| | - Xiang Zhao
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Academy for Advanced Interdisciplinary Studies, Henan University, Kaifeng, 475004, China
| | - Zhubing Hu
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Academy for Advanced Interdisciplinary Studies, Henan University, Kaifeng, 475004, China
| | - Siyi Guo
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Academy for Advanced Interdisciplinary Studies, Henan University, Kaifeng, 475004, China
| | - Dawei Yan
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Academy for Advanced Interdisciplinary Studies, Henan University, Kaifeng, 475004, China
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12
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Ivanauskas A, Inaba J, Zhao Y, Bottner-Parker KD, Wei W. Differential Symptomology, Susceptibility, and Titer Dynamics Manifested by Phytoplasma-Infected Periwinkle and Tomato Plants. PLANTS (BASEL, SWITZERLAND) 2024; 13:787. [PMID: 38592808 PMCID: PMC10974080 DOI: 10.3390/plants13060787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 03/08/2024] [Accepted: 03/09/2024] [Indexed: 04/11/2024]
Abstract
Phytoplasmas are intracellular pathogenic bacteria that infect a wide range of plant species, including agriculturally important crops and ornamental trees. However, our understanding of the relationship between symptom severity, disease progression, and phytoplasma concentration remains limited due to the inability to inoculate phytoplasmas mechanically into new plant hosts. The present study investigated phytoplasma titer dynamics and symptom development in periwinkle and tomato, both infected with the same potato purple top (PPT) phytoplasma strain using a small seedling grafting approach. Virescence, phyllody, and witches'-broom (WB) symptoms sequentially developed in periwinkle, while in tomato plants, big bud (BB, a form of phyllody), cauliflower-like inflorescence (CLI), and WB appeared in order. Results from quantitative polymerase chain reaction (qPCR) targeting the PPT phytoplasma's 16S rRNA gene revealed that in both host species, phytoplasma titers differed significantly at different infection stages. Notably, the highest phytoplasma concentration in periwinkles was observed in samples displaying phyllody symptoms, whereas in tomatoes, the titer peaked at the BB stage. Western blot analysis, utilizing an antibody specific to PPT phytoplasma, confirmed substantial phytoplasma presence in samples displaying phyllody and BB symptoms, consistent with the qPCR results. These findings challenge the conventional understanding that phytoplasma infection dynamics result in a higher titer at later stages, such as WB (excessive vegetative growth), rather than in the early stage, such as phyllody (abnormal reproductive growth). Furthermore, the PPT phytoplasma titer was markedly higher in periwinkles than in tomato plants, indicating differing susceptibilities between the hosts. This study reveals distinct host responses to PPT phytoplasma infection, providing valuable insights into phytoplasma titer dynamics and symptom development, with implications for the future management of agricultural disease.
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Affiliation(s)
- Algirdas Ivanauskas
- Molecular Plant Pathology Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, United States Department of Agriculture, Beltsville, MD 20705, USA; (A.I.); (J.I.); (Y.Z.); (K.D.B.-P.)
- Laboratory of Plant Pathology, Nature Research Centre, Akademijos Str. 2, LT-08412 Vilnius, Lithuania
| | - Junichi Inaba
- Molecular Plant Pathology Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, United States Department of Agriculture, Beltsville, MD 20705, USA; (A.I.); (J.I.); (Y.Z.); (K.D.B.-P.)
| | - Yan Zhao
- Molecular Plant Pathology Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, United States Department of Agriculture, Beltsville, MD 20705, USA; (A.I.); (J.I.); (Y.Z.); (K.D.B.-P.)
| | - Kristi D. Bottner-Parker
- Molecular Plant Pathology Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, United States Department of Agriculture, Beltsville, MD 20705, USA; (A.I.); (J.I.); (Y.Z.); (K.D.B.-P.)
| | - Wei Wei
- Molecular Plant Pathology Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, United States Department of Agriculture, Beltsville, MD 20705, USA; (A.I.); (J.I.); (Y.Z.); (K.D.B.-P.)
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13
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Liu K, Shi L, Luo H, Zhang K, Liu J, Qiu S, Li X, He S, Liu Z. Ralstonia solanacearum effector RipAK suppresses homodimerization of the host transcription factor ERF098 to enhance susceptibility and the sensitivity of pepper plants to dehydration. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 117:121-144. [PMID: 37738430 DOI: 10.1111/tpj.16479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 08/03/2023] [Accepted: 08/25/2023] [Indexed: 09/24/2023]
Abstract
Plants have evolved a sophisticated immune system to defend against invasion by pathogens. In response, pathogens deploy copious effectors to evade the immune responses. However, the molecular mechanisms used by pathogen effectors to suppress plant immunity remain unclear. Herein, we report that an effector secreted by Ralstonia solanacearum, RipAK, modulates the transcriptional activity of the ethylene-responsive factor ERF098 to suppress immunity and dehydration tolerance, which causes bacterial wilt in pepper (Capsicum annuum L.) plants. Silencing ERF098 enhances the resistance of pepper plants to R. solanacearum infection not only by inhibiting the host colonization of R. solanacearum but also by increasing the immunity and tolerance of pepper plants to dehydration and including the closure of stomata to reduce the loss of water in an abscisic acid signal-dependent manner. In contrast, the ectopic expression of ERF098 in Nicotiana benthamiana enhances wilt disease. We also show that RipAK targets and inhibits the ERF098 homodimerization to repress the expression of salicylic acid-dependent PR1 and dehydration tolerance-related OSR1 and OSM1 by cis-elements in their promoters. Taken together, our study reveals a regulatory mechanism used by the R. solanacearum effector RipAK to increase virulence by specifically inhibiting the homodimerization of ERF098 and reprogramming the transcription of PR1, OSR1, and OSM1 to boost susceptibility and dehydration sensitivity. Thus, our study sheds light on a previously unidentified strategy by which a pathogen simultaneously suppresses plant immunity and tolerance to dehydration by secreting an effector to interfere with the activity of a transcription factor and manipulate plant transcriptional programs.
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Affiliation(s)
- Kaisheng Liu
- Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Lanping Shi
- Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Hongli Luo
- Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Kan Zhang
- Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Jianxin Liu
- Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Shanshan Qiu
- Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Xia Li
- Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Shuilin He
- Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Zhiqin Liu
- Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
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14
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Rufián JS, Rueda-Blanco J, Beuzón CR, Ruiz-Albert J. Suppression of NLR-mediated plant immune detection by bacterial pathogens. JOURNAL OF EXPERIMENTAL BOTANY 2023; 74:6069-6088. [PMID: 37429579 PMCID: PMC10575702 DOI: 10.1093/jxb/erad246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Accepted: 07/10/2023] [Indexed: 07/12/2023]
Abstract
The plant immune system is constituted of two functionally interdependent branches that provide the plant with an effective defense against microbial pathogens. They can be considered separate since one detects extracellular pathogen-associated molecular patterns by means of receptors on the plant surface, while the other detects pathogen-secreted virulence effectors via intracellular receptors. Plant defense depending on both branches can be effectively suppressed by host-adapted microbial pathogens. In this review we focus on bacterially driven suppression of the latter, known as effector-triggered immunity (ETI) and dependent on diverse NOD-like receptors (NLRs). We examine how some effectors secreted by pathogenic bacteria carrying type III secretion systems can be subject to specific NLR-mediated detection, which can be evaded by the action of additional co-secreted effectors (suppressors), implying that virulence depends on the coordinated action of the whole repertoire of effectors of any given bacterium and their complex epistatic interactions within the plant. We consider how ETI activation can be avoided by using suppressors to directly alter compromised co-secreted effectors, modify plant defense-associated proteins, or occasionally both. We also comment on the potential assembly within the plant cell of multi-protein complexes comprising both bacterial effectors and defense protein targets.
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Affiliation(s)
- José S Rufián
- Instituto de Hortofruticultura Subtropical y Mediterránea ‘La Mayora’, Universidad de Málaga-Consejo Superior de Investigaciones Científicas (IHSM-UMA-CSIC), Depto. Biología Celular, Genética y Fisiología, Málaga, Spain
| | | | - Carmen R Beuzón
- Instituto de Hortofruticultura Subtropical y Mediterránea ‘La Mayora’, Universidad de Málaga-Consejo Superior de Investigaciones Científicas (IHSM-UMA-CSIC), Depto. Biología Celular, Genética y Fisiología, Málaga, Spain
| | - Javier Ruiz-Albert
- Instituto de Hortofruticultura Subtropical y Mediterránea ‘La Mayora’, Universidad de Málaga-Consejo Superior de Investigaciones Científicas (IHSM-UMA-CSIC), Depto. Biología Celular, Genética y Fisiología, Málaga, Spain
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15
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Inaba J, Kim BM, Zhao Y, Jansen AM, Wei W. The Endoplasmic Reticulum Is a Key Battleground between Phytoplasma Aggression and Host Plant Defense. Cells 2023; 12:2110. [PMID: 37626920 PMCID: PMC10453741 DOI: 10.3390/cells12162110] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Revised: 08/18/2023] [Accepted: 08/19/2023] [Indexed: 08/27/2023] Open
Abstract
Phytoplasmas are intracellular plant pathogens that heavily rely on host cell nutrients for survival and propagation due to their limited ability to synthesize essential substrates. The endoplasmic reticulum (ER), which plays a vital role in various cellular processes, including lipid and protein biosynthesis, is an attractive target for numerous intracellular pathogens to exploit. This study investigated the impact of potato purple top (PPT) phytoplasma infection on the ER in tomato plants. Abnormal accumulation of ER-resident proteins, disrupted ER network structures, and formation of protein aggregates in the phloem were observed using confocal microscopy and transmission electron microscopy, indicating a phytoplasma-infection-induced disturbance in ER homeostasis. The colocalization of phytoplasmas with the accumulated ER-resident proteins suggests an association between ER stress, unfolded protein response (UPR) induction, and phytoplasma infection and colonization, with the ER stress response likely contributing to the host plant's defense mechanisms. Quantitative real-time PCR revealed a negative correlation between ER stress/UPR activation and PPT phytoplasma titer, implying the involvement of UPR in curbing phytoplasma proliferation. Inducing ER stress and activating the UPR pathway effectively decreased phytoplasma titer, while suppressing the ER-resident protein, binding immunoglobulin protein (BiP) increased phytoplasma titer. These results highlight the ER as an intracellular battleground where phytoplasmas exploit host components for survival and multiplication, while host plants deploy defense mechanisms to counteract the invasion. Understanding the intricate interactions between phytoplasmas and plant hosts at the subcellular level, particularly within the ER, provides valuable insights for developing new strategies to control phytoplasma diseases.
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Affiliation(s)
- Junichi Inaba
- Molecular Plant Pathology Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, United States Department of Agriculture, Beltsville, MD 20705, USA; (J.I.); (B.M.K.); (Y.Z.)
| | - Bo Min Kim
- Molecular Plant Pathology Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, United States Department of Agriculture, Beltsville, MD 20705, USA; (J.I.); (B.M.K.); (Y.Z.)
| | - Yan Zhao
- Molecular Plant Pathology Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, United States Department of Agriculture, Beltsville, MD 20705, USA; (J.I.); (B.M.K.); (Y.Z.)
| | - Andrew M. Jansen
- Electron and Confocal Microscopy Unit, Beltsville Agricultural Research Center, Agricultural Research Service, United States Department of Agriculture, Beltsville, MD 20705, USA;
| | - Wei Wei
- Molecular Plant Pathology Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, United States Department of Agriculture, Beltsville, MD 20705, USA; (J.I.); (B.M.K.); (Y.Z.)
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16
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Ababa G. Biology, taxonomy, genetics, and management of Zymoseptoria tritici: the causal agent of wheat leaf blotch. Mycology 2023; 14:292-315. [PMID: 38187886 PMCID: PMC10769150 DOI: 10.1080/21501203.2023.2241492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 07/22/2023] [Indexed: 01/09/2024] Open
Abstract
Septoria tritici blotch or Septoria leaf blotch has been used for long time, but leaf blotch is a correct disease name. Moreover, Lb resistant gene is the correct name, but, not Stb gene. It has sexual and asexual parts on the mycelia, known as heterothallic fungi. Its pathogenic diversity ranged from 40% to 93% and has produced a wide variety of AvrLb6 haplotypes. M. graminicola has a plasmogamy and karyogamy sexual process. The pathogen can use macropycnidiospores, micropycnidiospores, and pycnidia vegetative growths for infection and overwintering. Synthetic M3, Kavkaz-K4500, Synthetic 6×, and TE9111 wheat genotypes have horizontal resistance. Avirulence (Avr) genes in Z. tritici and their matching wheat (R) genes indicate gene for gene mechanisms of resistance. Twenty-two R genes (vertical resistance) have been identified. In both horizontal and vertical resistance, different Lb genes have been broken down due to new Z.tritici virulent gene and currently Lb19 resistant gene is being recommended. Mixing of resistant and susceptible cultivars is also the most effective management strategy. Moreover, different cultural practices and biological control have been proposed. Lastly, different fungicides are also available. However, in developing countries cultivar mixture, isolates diversity, biological control, and epidemic studies have been greatly missed.
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Affiliation(s)
- Girma Ababa
- Department of Plant Protection (Plant Pathology), Holetta Agricultural Research Center (HARC), Ethiopian Institute of Agricultural Research (EIAR), Holetta, Addis Ababa, Ethiopia
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17
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Wu CH, Derevnina L. The battle within: How pathogen effectors suppress NLR-mediated immunity. CURRENT OPINION IN PLANT BIOLOGY 2023; 74:102396. [PMID: 37295294 DOI: 10.1016/j.pbi.2023.102396] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 04/21/2023] [Accepted: 05/10/2023] [Indexed: 06/12/2023]
Abstract
To successfully colonise plants, pathogens must circumvent the plant immune system. Intracellular immune receptors of the nucleotide-binding leucine-rich repeat (NLR) class of proteins are major components of the plant immune system. NLRs function as disease resistance genes by recognising effectors secreted by diverse pathogens, triggering a localised form of programmed cell death known as the hypersensitive response. To evade detection, effectors have evolved to suppress NLR-mediated immunity by targeting NLRs either directly or indirectly. Here, we compile the latest discoveries related to NLR-suppressing effectors and categorise these effectors based on their mode of action. We discuss the diverse strategies pathogens use to perturb NLR-mediated immunity, and how we can use our understanding of effector activity to help guide new approaches for disease resistance breeding.
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Affiliation(s)
- Chih-Hang Wu
- Institute of Plant and Microbial Biology, Academia Sinica, Nankang, Taipei, Taiwan
| | - Lida Derevnina
- Crop Science Centre, Department of Plant Science, University of Cambridge, Cambridge, United Kingdom.
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18
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Geraffi N, Gupta P, Wagner N, Barash I, Pupko T, Sessa G. Comparative sequence analysis of pPATH pathogenicity plasmids in Pantoea agglomerans gall-forming bacteria. FRONTIERS IN PLANT SCIENCE 2023; 14:1198160. [PMID: 37583594 PMCID: PMC10425158 DOI: 10.3389/fpls.2023.1198160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 07/10/2023] [Indexed: 08/17/2023]
Abstract
Acquisition of the pathogenicity plasmid pPATH that encodes a type III secretion system (T3SS) and effectors (T3Es) has likely led to the transition of a non-pathogenic bacterium into the tumorigenic pathogen Pantoea agglomerans. P. agglomerans pv. gypsophilae (Pag) forms galls on gypsophila (Gypsophila paniculata) and triggers immunity on sugar beet (Beta vulgaris), while P. agglomerans pv. betae (Pab) causes galls on both gypsophila and sugar beet. Draft sequences of the Pag and Pab genomes were previously generated using the MiSeq Illumina technology and used to determine partial T3E inventories of Pab and Pag. Here, we fully assembled the Pab and Pag genomes following sequencing with PacBio technology and carried out a comparative sequence analysis of the Pab and Pag pathogenicity plasmids pPATHpag and pPATHpab. Assembly of Pab and Pag genomes revealed a ~4 Mbp chromosome with a 55% GC content, and three and four plasmids in Pab and Pag, respectively. pPATHpag and pPATHpab share 97% identity within a 74% coverage, and a similar GC content (51%); they are ~156 kb and ~131 kb in size and consist of 198 and 155 coding sequences (CDSs), respectively. In both plasmids, we confirmed the presence of highly similar gene clusters encoding a T3SS, as well as auxin and cytokinins biosynthetic enzymes. Three putative novel T3Es were identified in Pab and one in Pag. Among T3SS-associated proteins encoded by Pag and Pab, we identified two novel chaperons of the ShcV and CesT families that are present in both pathovars with high similarity. We also identified insertion sequences (ISs) and transposons (Tns) that may have contributed to the evolution of the two pathovars. These include seven shared IS elements, and three ISs and two transposons unique to Pab. Finally, comparative sequence analysis revealed plasmid regions and CDSs that are present only in pPATHpab or in pPATHpag. The high similarity and common features of the pPATH plasmids support the hypothesis that the two strains recently evolved into host-specific pathogens.
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Affiliation(s)
- Naama Geraffi
- School of Plant Sciences and Food Security, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Priya Gupta
- School of Plant Sciences and Food Security, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Naama Wagner
- The Shmunis School of Biomedicine and Cancer Research, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Isaac Barash
- School of Plant Sciences and Food Security, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Tal Pupko
- The Shmunis School of Biomedicine and Cancer Research, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Guido Sessa
- School of Plant Sciences and Food Security, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
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19
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Breeze E, Vale V, McLellan H, Pecrix Y, Godiard L, Grant M, Frigerio L. A tell tail sign: a conserved C-terminal tail-anchor domain targets a subset of pathogen effectors to the plant endoplasmic reticulum. JOURNAL OF EXPERIMENTAL BOTANY 2023; 74:3188-3202. [PMID: 36860200 DOI: 10.1093/jxb/erad075] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Accepted: 02/27/2023] [Indexed: 05/21/2023]
Abstract
The endoplasmic reticulum (ER) is the entry point to the secretory pathway and, as such, is critical for adaptive responses to biotic stress, when the demand for de novo synthesis of immunity-related proteins and signalling components increases significantly. Successful phytopathogens have evolved an arsenal of small effector proteins which collectively reconfigure multiple host components and signalling pathways to promote virulence; a small, but important, subset of which are targeted to the endomembrane system including the ER. We identified and validated a conserved C-terminal tail-anchor motif in a set of pathogen effectors known to localize to the ER from the oomycetes Hyaloperonospora arabidopsidis and Plasmopara halstedii (downy mildew of Arabidopsis and sunflower, respectively) and used this protein topology to develop a bioinformatic pipeline to identify putative ER-localized effectors within the effectorome of the related oomycete, Phytophthora infestans, the causal agent of potato late blight. Many of the identified P. infestans tail-anchor effectors converged on ER-localized NAC transcription factors, indicating that this family is a critical host target for multiple pathogens.
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Affiliation(s)
- Emily Breeze
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | - Victoria Vale
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | - Hazel McLellan
- Division of Plant Science, University of Dundee (at JHI), Invergowrie, Dundee DD2 5DA, UK
| | - Yann Pecrix
- CIRAD, UMR PVBMT, Peuplements Végétaux et Bioagresseurs en Milieu Tropical (UMR C53), Ligne Paradis, 97410 St Pierre, La Réunion, France
| | - Laurence Godiard
- Laboratoire des Interactions Plantes Microbes Environnement (LIPME), Institut National de Recherche pour l'Agriculture, l'Alimentation, et l'Environnement (INRAE), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Castanet-Tolosan, France
| | - Murray Grant
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | - Lorenzo Frigerio
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
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Umer MJ, Zheng J, Yang M, Batool R, Abro AA, Hou Y, Xu Y, Gebremeskel H, Wang Y, Zhou Z, Cai X, Liu F, Zhang B. Insights to Gossypium defense response against Verticillium dahliae: the Cotton Cancer. Funct Integr Genomics 2023; 23:142. [PMID: 37121989 DOI: 10.1007/s10142-023-01065-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 04/15/2023] [Accepted: 04/19/2023] [Indexed: 05/02/2023]
Abstract
The soil-borne pathogen Verticillium dahliae, also referred as "The Cotton Cancer," is responsible for causing Verticillium wilt in cotton crops, a destructive disease with a global impact. To infect cotton plants, the pathogen employs multiple virulence mechanisms such as releasing enzymes that degrade cell walls, activating genes that contribute to virulence, and using protein effectors. Conversely, cotton plants have developed numerous defense mechanisms to combat the impact of V. dahliae. These include strengthening the cell wall by producing lignin and depositing callose, discharging reactive oxygen species, and amassing hormones related to defense. Despite the efforts to develop resistant cultivars, there is still no permanent solution to Verticillium wilt due to a limited understanding of the underlying molecular mechanisms that drive both resistance and pathogenesis is currently prevalent. To address this challenge, cutting-edge technologies such as clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9), host-induced gene silencing (HIGS), and gene delivery via nano-carriers could be employed as effective alternatives to control the disease. This article intends to present an overview of V. dahliae virulence mechanisms and discuss the different cotton defense mechanisms against Verticillium wilt, including morphophysiological and biochemical responses and signaling pathways including jasmonic acid (JA), salicylic acid (SA), ethylene (ET), and strigolactones (SLs). Additionally, the article highlights the significance of microRNAs (miRNAs), circular RNAs (circRNAs), and long non-coding RNAs (lncRNAs) in gene expression regulation, as well as the different methods employed to identify and functionally validate genes to achieve resistance against this disease. Gaining a more profound understanding of these mechanisms could potentially result in the creation of more efficient strategies for combating Verticillium wilt in cotton crops.
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Affiliation(s)
- Muhammad Jawad Umer
- State Key Laboratory of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China
| | - Jie Zheng
- State Key Laboratory of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China
- Hainan Yazhou Bay Seed Laboratory, China/National Nanfan, Research Institute of Chinese Academy of Agricultural Sciences, Sanya, 572025, China
| | - Mengying Yang
- State Key Laboratory of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
| | - Raufa Batool
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Aamir Ali Abro
- State Key Laboratory of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China
| | - Yuqing Hou
- State Key Laboratory of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China
| | - Yanchao Xu
- State Key Laboratory of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China
| | - Haileslassie Gebremeskel
- Mehoni Agricultural Research Center, Ethiopian Institute of Agricultural Research, Addis Ababa, Ethiopia
| | - Yuhong Wang
- State Key Laboratory of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China
| | - ZhongLi Zhou
- State Key Laboratory of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China
| | - Xiaoyan Cai
- State Key Laboratory of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China
- Hainan Yazhou Bay Seed Laboratory, China/National Nanfan, Research Institute of Chinese Academy of Agricultural Sciences, Sanya, 572025, China
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University/Institute of Cotton Research, Chinese Academy of Agricultural Science, Anyang, China
| | - Fang Liu
- State Key Laboratory of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China.
- Hainan Yazhou Bay Seed Laboratory, China/National Nanfan, Research Institute of Chinese Academy of Agricultural Sciences, Sanya, 572025, China.
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China.
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University/Institute of Cotton Research, Chinese Academy of Agricultural Science, Anyang, China.
| | - Baohong Zhang
- State Key Laboratory of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China.
- Department of Biology, East Carolina University, Greenville, NC, 27858, USA.
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Jeon H, Segonzac C. Manipulation of the Host Endomembrane System by Bacterial Effectors. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2023; 36:208-217. [PMID: 36645655 DOI: 10.1094/mpmi-09-22-0190-fi] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
The endomembrane system, extending from the nuclear envelope to the plasma membrane, is critical to the plant response to pathogen infection. Synthesis and transport of immunity-related proteins and antimicrobial compounds to and from the plasma membrane are supported by conventional and unconventional processes of secretion and internalization of vesicles, guided by the cytoskeleton networks. Although plant bacterial pathogens reside mostly in the apoplast, major structural and functional modifications of the endomembrane system in the host cell occur during bacterial infection. Here, we review the dynamics of these cellular compartments, briefly, for their essential contributions to the plant defense responses and, in parallel, for their emerging roles in bacterial pathogenicity. We further focus on Pseudomonas syringae, Xanthomonas spp., and Ralstonia solanacearum type III secreted effectors that one or both localize to and associate with components of the host endomembrane system or the cytoskeleton network to highlight the diversity of virulence strategies deployed by bacterial pathogens beyond the inhibition of the secretory pathway. [Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
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Affiliation(s)
- Hyelim Jeon
- Department of Agriculture, Forestry and Bioresources, Seoul National University, Seoul, 08826, Republic of Korea
- Plant Immunity Research Center, Seoul National University, Seoul 08826, Republic of Korea
| | - Cécile Segonzac
- Department of Agriculture, Forestry and Bioresources, Seoul National University, Seoul, 08826, Republic of Korea
- Plant Immunity Research Center, Seoul National University, Seoul 08826, Republic of Korea
- Plant Genomics and Breeding Institute, Seoul National University, Seoul, 08826, Republic of Korea
- Agricultural and Life Science Research Institute, Seoul National University, Seoul, 08826, Republic of Korea
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22
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Yang F, Li G, Felix G, Albert M, Guo M. Engineered Agrobacterium improves transformation by mitigating plant immunity detection. THE NEW PHYTOLOGIST 2023; 237:2493-2504. [PMID: 36564969 DOI: 10.1111/nph.18694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 12/16/2022] [Indexed: 06/17/2023]
Abstract
Agrobacterium tumefaciens microbe-associated molecular pattern elongation factor Tu (EF-Tu) is perceived by orthologs of the Arabidopsis immune receptor EFR activating pattern-triggered immunity (PTI) that causes reduced T-DNA-mediated transient expression. We altered EF-Tu in A. tumefaciens to reduce PTI and improved transformation efficiency. A robust computational pipeline was established to detect EF-Tu protein variation in a large set of plant bacterial species and identified EF-Tu variants from bacterial pathogen Pseudomonas syringae pv. tomato DC3000 that allow the pathogen to escape EFR perception. Agrobacterium tumefaciens strains were engineered to substitute EF-Tu with DC3000 variants and examined their transformation efficiency in plants. Elongation factor Tu variants with rarely occurred amino acid residues were identified within DC3000 EF-Tu that mitigates recognition by EFR. Agrobacterium tumefaciens strains were engineered by expressing DC3000 EF-Tu instead of native agrobacterial EF-Tu and resulted in decreased plant immunity detection. These engineered A. tumefaciens strains displayed an increased efficiency in transient expression in both Arabidopsis thaliana and Camelina sativa. The results support the potential application of these strains as improved vehicles to introduce transgenic alleles into members of the Brassicaceae family.
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Affiliation(s)
- Fan Yang
- Department of Plant Pathology, University of Nebraska-Lincoln, Lincoln, NE, 68588-0722, USA
- Center for Plant Science Innovation, University of Nebraska-Lincoln, Lincoln, NE, 68588-0660, USA
| | - Guangyong Li
- Department of Plant Pathology, University of Nebraska-Lincoln, Lincoln, NE, 68588-0722, USA
- Center for Plant Science Innovation, University of Nebraska-Lincoln, Lincoln, NE, 68588-0660, USA
| | - Georg Felix
- Center for Plant Molecular Biology (ZMBP), University of Tübingen, Tübingen, 72074, Germany
| | - Markus Albert
- Department of Biology, Molecular Plant Physiology, University of Erlangen, Erlangen, 91054, Germany
| | - Ming Guo
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, NE, 68588-0664, USA
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De Ryck J, Van Damme P, Goormachtig S. From prediction to function: Current practices and challenges towards the functional characterization of type III effectors. Front Microbiol 2023; 14:1113442. [PMID: 36846751 PMCID: PMC9945535 DOI: 10.3389/fmicb.2023.1113442] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 01/19/2023] [Indexed: 02/10/2023] Open
Abstract
The type III secretion system (T3SS) is a well-studied pathogenicity determinant of many bacteria through which effectors (T3Es) are translocated into the host cell, where they exercise a wide range of functions to deceive the host cell's immunity and to establish a niche. Here we look at the different approaches that are used to functionally characterize a T3E. Such approaches include host localization studies, virulence screenings, biochemical activity assays, and large-scale omics, such as transcriptomics, interactomics, and metabolomics, among others. By means of the phytopathogenic Ralstonia solanacearum species complex (RSSC) as a case study, the current advances of these methods will be explored, alongside the progress made in understanding effector biology. Data obtained by such complementary methods provide crucial information to comprehend the entire function of the effectome and will eventually lead to a better understanding of the phytopathogen, opening opportunities to tackle it.
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Affiliation(s)
- Joren De Ryck
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Center for Plant Systems Biology, VIB, Ghent, Belgium
- iRIP Unit, Laboratory of Microbiology, Department of Biochemistry and Microbiology, Ghent University, Ghent, Belgium
| | - Petra Van Damme
- iRIP Unit, Laboratory of Microbiology, Department of Biochemistry and Microbiology, Ghent University, Ghent, Belgium
| | - Sofie Goormachtig
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Center for Plant Systems Biology, VIB, Ghent, Belgium
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Todd JNA, Carreón-Anguiano KG, Islas-Flores I, Canto-Canché B. Fungal Effectoromics: A World in Constant Evolution. Int J Mol Sci 2022; 23:13433. [PMID: 36362218 PMCID: PMC9656242 DOI: 10.3390/ijms232113433] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 10/25/2022] [Accepted: 10/31/2022] [Indexed: 10/28/2023] Open
Abstract
Effectors are small, secreted molecules that mediate the establishment of interactions in nature. While some concepts of effector biology have stood the test of time, this area of study is ever-evolving as new effectors and associated characteristics are being revealed. In the present review, the different characteristics that underly effector classifications are discussed, contrasting past and present knowledge regarding these molecules to foster a more comprehensive understanding of effectors for the reader. Research gaps in effector identification and perspectives for effector application in plant disease management are also presented, with a focus on fungal effectors in the plant-microbe interaction and interactions beyond the plant host. In summary, the review provides an amenable yet thorough introduction to fungal effector biology, presenting noteworthy examples of effectors and effector studies that have shaped our present understanding of the field.
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Affiliation(s)
- Jewel Nicole Anna Todd
- Unidad de Biotecnología, Centro de Investigación Científica de Yucatán, A.C., Calle 43 No. 130 x 32 y 34, Colonia Chuburná de Hidalgo, Mérida C.P. 97205, Yucatán, Mexico
| | - Karla Gisel Carreón-Anguiano
- Unidad de Biotecnología, Centro de Investigación Científica de Yucatán, A.C., Calle 43 No. 130 x 32 y 34, Colonia Chuburná de Hidalgo, Mérida C.P. 97205, Yucatán, Mexico
| | - Ignacio Islas-Flores
- Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de Yucatán, A.C., Calle 43 No. 130 x 32 y 34, Colonia Chuburná de Hidalgo, Mérida C.P. 97205, Yucatán, Mexico
| | - Blondy Canto-Canché
- Unidad de Biotecnología, Centro de Investigación Científica de Yucatán, A.C., Calle 43 No. 130 x 32 y 34, Colonia Chuburná de Hidalgo, Mérida C.P. 97205, Yucatán, Mexico
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25
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Sugimoto H, Tanaka T, Muramoto N, Kitagawa-Yogo R, Mitsukawa N. Transcription factor NTL9 negatively regulates Arabidopsis vascular cambium development during stem secondary growth. PLANT PHYSIOLOGY 2022; 190:1731-1746. [PMID: 35951755 PMCID: PMC9614505 DOI: 10.1093/plphys/kiac368] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Accepted: 07/09/2022] [Indexed: 06/15/2023]
Abstract
In plant stems, secondary vascular development is established through the differentiation of cylindrical vascular cambium, producing secondary xylem (wood) and phloem (bast), which have economic importance. However, there is a dearth of knowledge on the genetic mechanism underlying this process. NAC with Transmembrane Motif 1-like transcription factor 9 (NTL9) plays a central role in abiotic and immune signaling responses. Here, we investigated the role of NTL9 in vascular cambium development in Arabidopsis (Arabidopsis thaliana) inflorescence stems by identifying and characterizing an Arabidopsis phloem circular-timing (pct) mutant. The pct mutant exhibited enhanced vascular cambium formation following secondary phloem production. In the pct mutant, although normal organization in vascular bundles was maintained, vascular cambium differentiation occurred at an early stage of stem development, which was associated with increased expression of cambium-/phloem-related genes and enhanced cambium activity. The pct mutant stem phenotype was caused by a recessive frameshift mutation that disrupts the transmembrane (TM) domain of NTL9. Our results indicate that NTL9 functions as a negative regulator of cambial activity and has a suppressive role in developmental transition to the secondary growth phase in stem vasculature, which is necessary for its precise TM domain-mediated regulation.
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Affiliation(s)
| | | | - Nobuhiko Muramoto
- Toyota Central R&D Laboratories, Inc., Nagakute, Aichi 480-1192, Japan
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Bai S, Niu Q, Wu Y, Xu K, Miao M, Mei J. Genome-Wide Identification of the NAC Transcription Factors in Gossypium hirsutum and Analysis of Their Responses to Verticillium wilt. PLANTS (BASEL, SWITZERLAND) 2022; 11:2661. [PMID: 36235527 PMCID: PMC9571985 DOI: 10.3390/plants11192661] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 09/27/2022] [Accepted: 10/06/2022] [Indexed: 06/16/2023]
Abstract
The NAC transcription factors (NACs) are among the largest plant-specific gene regulators and play essential roles in the transcriptional regulation of both biotic and abiotic stress responses. Verticillium wilt of cotton caused by Verticillium dahliae (V. dahliae) is a destructive soil-borne disease that severely decreases cotton yield and quality. Although NACs constitute a large family in upland cotton (G. hirsutum L.), there is little systematic investigation of the NACs’ responsive to V. dahliae that has been reported. To further explore the key NACs in response to V. dahliae resistance and obtain a better comprehension of the molecular basis of the V. dahliae stress response in cotton, a genome-wide survey was performed in this study. To investigate the roles of GhNACs under V. dahliae induction in upland cotton, mRNA libraries were constructed from mocked and infected roots of upland cotton cultivars with the V. dahliae-sensitive cultivar “Jimian 11” (J11) and V. dahliae-tolerant cultivar “Zhongzhimian 2” (Z2). A total of 271 GhNACs were identified. Genome analysis showed GhNACs phylogenetically classified into 12 subfamilies and distributed across 26 chromosomes and 20 scaffolds. A comparative transcriptome analysis revealed 54 GhNACs were differentially expressed under V. dahliae stress, suggesting a potential role of these GhNACs in disease response. Additionally, one NAC090 homolog, GhNAC204, could be a positive regulator of cotton resistance to V. dahliae infection. These results give insight into the GhNAC gene family, identify GhNACs’ responsiveness to V. dahliae infection, and provide potential molecular targets for future studies for improving V. dahliae resistance in cotton.
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Affiliation(s)
| | | | | | | | | | - Jun Mei
- Correspondence: (M.M.); (J.M.)
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27
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Yactayo-Chang JP, Hunter CT, Alborn HT, Christensen SA, Block AK. Production of the Green Leaf Volatile (Z)-3-Hexenal by a Zea mays Hydroperoxide Lyase. PLANTS 2022; 11:plants11172201. [PMID: 36079583 PMCID: PMC9460041 DOI: 10.3390/plants11172201] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 08/17/2022] [Accepted: 08/22/2022] [Indexed: 11/16/2022]
Abstract
Plant-produced volatile compounds play important roles in plant signaling and in the communication of plants with other organisms. Many plants emit green leaf volatiles (GLVs) in response to damage or attack, which serve to warn neighboring plants or attract predatory or parasitic insects to help defend against insect pests. GLVs include aldehydes, esters, and alcohols of 6-carbon compounds that are released rapidly following wounding. One GLV produced by maize (Zea mays) is the volatile (Z)-3-hexenal; this volatile is produced from the cleavage of (9Z,11E,15Z)-octadecatrienoic acid by hydroperoxide lyases (HPLs) of the cytochrome P450 CYP74B family. The specific HPL in maize involved in (Z)-3-hexenal production had not been determined. In this study, we used phylogenetics with known HPLs from other species to identify a candidate HPL from maize (ZmHPL). To test the ability of the putative HPL to produce (Z)-3-hexenal, we constitutively expressed the gene in Arabidopsis thaliana ecotype Columbia-0 that contains a natural loss-of-function mutant in AtHPL and examined the transgenic plants for restored (Z)-3-hexenal production. Volatile analysis of leaves from these transgenic plants showed that they did produce (Z)-3-hexenal, confirming that ZmHPL can produce (Z)-3-hexenal in vivo. Furthermore, we used gene expression analysis to show that expression of ZmHPL is induced in maize in response to both wounding and the insect pests Spodoptera frugiperda and Spodoptera exigua. Our study demonstrates that ZmHPL can produce GLVs and highlights its likely role in (Z)-3-hexenal production in response to mechanical damage and herbivory in maize.
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28
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Maia T, Rody HVS, Bombardelli RGH, Souto TG, Camargo LEA, Monteiro-Vitorello CB. A Bacterial Type Three Secretion-Based Delivery System for Functional Characterization of Sporisorium scitamineum Plant Immune Suppressing Effector Proteins. PHYTOPATHOLOGY 2022; 112:1513-1523. [PMID: 35050679 DOI: 10.1094/phyto-08-21-0326-r] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The facultative biotrophic basidiomycete Sporisorium scitamineum causes smut disease in sugarcane. This study applied an assay to identify S. scitamineum candidate effectors (CEs) with plant immunity suppression activities by delivering them into Nicotiana benthamiana cells via the type-three secretion system of Pseudomonas fluorescens EtHAn. Six CEs were individually cloned into the pEDV6 vector and expressed by P. fluorescens EtHAn for translocation into the plant cells. Three CEs (g1052, g3890, and g5159) could suppress pattern-triggered immunity (PTI) responses with high reproducibility in different coinfiltration experiments with P. syringae pv. tomato DC3000. In addition, three CEs (g1052, g4549, and g5159) were also found to be AvrB-induced suppressors of effector-triggered immunity (ETI), demonstrating for the first time that S. scitamineum can defeat both PTI and ETI responses. A transcriptomic analysis at different stages of infection by the smut fungus of three sugarcane cultivars with contrasting responses to the pathogen revealed that suppressors g1052, g3890, g4549, and g5159 were induced at the early stage of infection. By contrast, the two CEs (g2666 and g6610) that did not exhibit suppression activities expressed only at the late stage of infection. Moreover, genomic structures of the CEs and searches for orthologs in other smut species suggested duplication events and further divergence in CEs evolution of S. scitamineum. Thus, the transient assay applied here demonstrated the potential of pEDV6 and P. fluorescens EtHAn as biological tools for identifying plant immune suppressors from S. scitamineum.
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Affiliation(s)
- Thiago Maia
- Departamento de Fitopatologia e Nematologia, Universidade de São Paulo (USP), Escola Superior de Agricultura Luiz de Queiroz (ESALQ), Piracicaba, SP, Brazil
- Departamento de Genética, USP, ESALQ, Piracicaba, SP, Brazil
| | - Hugo V S Rody
- Departamento de Genética, USP, ESALQ, Piracicaba, SP, Brazil
| | | | - Tiarla Graciane Souto
- Departamento de Fitopatologia e Nematologia, Universidade de São Paulo (USP), Escola Superior de Agricultura Luiz de Queiroz (ESALQ), Piracicaba, SP, Brazil
- Departamento de Genética, USP, ESALQ, Piracicaba, SP, Brazil
| | - Luis Eduardo Aranha Camargo
- Departamento de Fitopatologia e Nematologia, Universidade de São Paulo (USP), Escola Superior de Agricultura Luiz de Queiroz (ESALQ), Piracicaba, SP, Brazil
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De Backer J, Van Breusegem F, De Clercq I. Proteolytic Activation of Plant Membrane-Bound Transcription Factors. FRONTIERS IN PLANT SCIENCE 2022; 13:927746. [PMID: 35774815 PMCID: PMC9237531 DOI: 10.3389/fpls.2022.927746] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Accepted: 05/23/2022] [Indexed: 06/03/2023]
Abstract
Due to the presence of a transmembrane domain, the subcellular mobility plan of membrane-bound or membrane-tethered transcription factors (MB-TFs) differs from that of their cytosolic counterparts. The MB-TFs are mostly locked in (sub)cellular membranes, until they are released by a proteolytic cleavage event or when the transmembrane domain (TMD) is omitted from the transcript due to alternative splicing. Here, we review the current knowledge on the proteolytic activation mechanisms of MB-TFs in plants, with a particular focus on regulated intramembrane proteolysis (RIP), and discuss the analogy with the proteolytic cleavage of MB-TFs in animal systems. We present a comprehensive inventory of all known and predicted MB-TFs in the model plant Arabidopsis thaliana and examine their experimentally determined or anticipated subcellular localizations and membrane topologies. We predict proteolytically activated MB-TFs by the mapping of protease recognition sequences and structural features that facilitate RIP in and around the TMD, based on data from metazoan intramembrane proteases. Finally, the MB-TF functions in plant responses to environmental stresses and in plant development are considered and novel functions for still uncharacterized MB-TFs are forecasted by means of a regulatory network-based approach.
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Affiliation(s)
- Jonas De Backer
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Vlaams Instituut voor Biotechnologie (VIB)-Center for Plant Systems Biology, Ghent, Belgium
| | - Frank Van Breusegem
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Vlaams Instituut voor Biotechnologie (VIB)-Center for Plant Systems Biology, Ghent, Belgium
| | - Inge De Clercq
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Vlaams Instituut voor Biotechnologie (VIB)-Center for Plant Systems Biology, Ghent, Belgium
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30
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Deb S, Gokulan CG, Nathawat R, Patel HK, Sonti RV. Suppression of XopQ-XopX-induced immune responses of rice by the type III effector XopG. MOLECULAR PLANT PATHOLOGY 2022; 23:634-648. [PMID: 35150038 PMCID: PMC8995061 DOI: 10.1111/mpp.13184] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 12/01/2021] [Accepted: 12/23/2021] [Indexed: 06/14/2023]
Abstract
Effectors that suppress effector-triggered immunity (ETI) are an essential part of the arms race in the co-evolution of bacterial pathogens and their host plants. Xanthomonas oryzae pv. oryzae uses multiple type III secretion system (T3SS) secreted effectors such as XopU, XopV, XopP, XopG, and AvrBs2 to suppress rice immune responses that are induced by the interaction of two other effectors, XopQ and XopX. Here we show that each of these five suppressors can interact individually with both XopQ and XopX. One of the suppressors, XopG, is a predicted metallopeptidase that appears to have been introduced into X. oryzae pv. oryzae by horizontal gene transfer. XopQ and XopX interact with each other in the nucleus while interaction with XopG sequesters them in the cytoplasm. The XopG E76A and XopG E85A mutants are defective in interaction with XopQ and XopX, and are also defective in suppression of XopQ-XopX-mediated immune responses. Both mutations individually affect the virulence-promoting ability of XopG. These results indicate that XopG is important for X. oryzae pv. oryzae virulence and provide insights into the mechanisms by which this protein suppresses ETI in rice.
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Affiliation(s)
- Sohini Deb
- CSIR ‐ Centre for Cellular and Molecular Biology (CSIR‐CCMB)HyderabadIndia
- Department of Plant and Environmental SciencesUniversity of CopenhagenFrederiksberg CDenmark
| | - C. G. Gokulan
- CSIR ‐ Centre for Cellular and Molecular Biology (CSIR‐CCMB)HyderabadIndia
| | - Rajkanwar Nathawat
- CSIR ‐ Centre for Cellular and Molecular Biology (CSIR‐CCMB)HyderabadIndia
| | - Hitendra K. Patel
- CSIR ‐ Centre for Cellular and Molecular Biology (CSIR‐CCMB)HyderabadIndia
| | - Ramesh V. Sonti
- CSIR ‐ Centre for Cellular and Molecular Biology (CSIR‐CCMB)HyderabadIndia
- Indian Institute of Science Education and Research (IISER) TirupatiTirupatiIndia
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Host-specific signal perception by PsaR2 LuxR solo induces Pseudomonas syringae pv. actinidiae virulence traits. Microbiol Res 2022; 260:127048. [DOI: 10.1016/j.micres.2022.127048] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 03/23/2022] [Accepted: 04/19/2022] [Indexed: 11/19/2022]
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Ma A, Zhang D, Wang G, Wang K, Li Z, Gao Y, Li H, Bian C, Cheng J, Han Y, Yang S, Gong Z, Qi J. Verticillium dahliae effector VDAL protects MYB6 from degradation by interacting with PUB25 and PUB26 E3 ligases to enhance Verticillium wilt resistance. THE PLANT CELL 2021; 33:3675-3699. [PMID: 34469582 PMCID: PMC8643689 DOI: 10.1093/plcell/koab221] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 08/26/2021] [Indexed: 05/30/2023]
Abstract
Verticillium wilt is a severe plant disease that causes massive losses in multiple crops. Increasing the plant resistance to Verticillium wilt is a critical challenge worldwide. Here, we report that the hemibiotrophic Verticillium dahliae-secreted Asp f2-like protein VDAL causes leaf wilting when applied to cotton leaves in vitro but enhances the resistance to V. dahliae when overexpressed in Arabidopsis or cotton without affecting the plant growth and development. VDAL protein interacts with Arabidopsis E3 ligases plant U-box 25 (PUB25) and PUB26 and is ubiquitinated by PUBs in vitro. However, VDAL is not degraded by PUB25 or PUB26 in planta. Besides, the pub25 pub26 double mutant shows higher resistance to V. dahliae than the wild-type. PUBs interact with the transcription factor MYB6 in a yeast two-hybrid screen. MYB6 promotes plant resistance to Verticillium wilt while PUBs ubiquitinate MYB6 and mediate its degradation. VDAL competes with MYB6 for binding to PUBs, and the role of VDAL in increasing Verticillium wilt resistance depends on MYB6. Taken together, these results suggest that plants evolute a strategy to utilize the invaded effector protein VDAL to resist the V. dahliae infection without causing a hypersensitive response (HR); alternatively, hemibiotrophic pathogens may use some effectors to keep plant cells alive during its infection in order to take nutrients from host cells. This study provides the molecular mechanism for plants increasing disease resistance when overexpressing some effector proteins without inducing HR, and may promote searching for more genes from pathogenic fungi or bacteria to engineer plant disease resistance.
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Affiliation(s)
- Aifang Ma
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Dingpeng Zhang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
- Department of Neurosurgery, University of Florida, Gainesville, Florida 32608, USA
| | - Guangxing Wang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Kai Wang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng 475001, China
| | - Zhen Li
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Yuanhui Gao
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Hengchang Li
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Chao Bian
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
- Department of Plant Biology and Genome Center, University of California, Davis, California 95616, USA
| | - Jinkui Cheng
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Yinan Han
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Shuhua Yang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Zhizhong Gong
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
- College of Life Science, Hebei University, Baoding 071002, China
| | - Junsheng Qi
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
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Denne NL, Hiles RR, Kyrysyuk O, Iyer-Pascuzzi AS, Mitra RM. Ralstonia solanacearum Effectors Localize to Diverse Organelles in Solanum Hosts. PHYTOPATHOLOGY 2021; 111:2213-2226. [PMID: 33720750 DOI: 10.1094/phyto-10-20-0483-r] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Phytopathogenic bacteria secrete type III effector (T3E) proteins directly into host plant cells. T3Es can interact with plant proteins and frequently manipulate plant host physiological or developmental processes. The proper subcellular localization of T3Es is critical for their ability to interact with plant targets, and knowledge of T3E localization can be informative for studies of effector function. Here we investigated the subcellular localization of 19 T3Es from the phytopathogenic bacteria Ralstonia pseudosolanacearum and Ralstonia solanacearum. Approximately 45% of effectors in our library localize to both the plant cell periphery and the nucleus, 15% exclusively to the cell periphery, 15% exclusively to the nucleus, and 25% to other organelles, including tonoplasts and peroxisomes. Using tomato hairy roots, we show that T3E localization is similar in both leaves and roots and is not impacted by Solanum species. We find that in silico prediction programs are frequently inaccurate, highlighting the value of in planta localization experiments. Our data suggest that Ralstonia targets a wide diversity of cellular organelles and provides a foundation for developing testable hypotheses about Ralstonia effector function.
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Affiliation(s)
- Nina L Denne
- Department of Biology, Carleton College, Northfield, MN 55057
| | - Rachel R Hiles
- Department of Botany and Plant Pathology and Center for Plant Biology, Purdue University, West Lafayette, IN 47907
| | | | - Anjali S Iyer-Pascuzzi
- Department of Botany and Plant Pathology and Center for Plant Biology, Purdue University, West Lafayette, IN 47907
| | - Raka M Mitra
- Department of Biology, Carleton College, Northfield, MN 55057
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Ai G, Zhu H, Fu X, Liu J, Li T, Cheng Y, Zhou Y, Yang K, Pan W, Zhang H, Wu Z, Dong S, Xia Y, Wang Y, Xia A, Wang Y, Dou D, Jing M. Phytophthora infection signals-induced translocation of NAC089 is required for endoplasmic reticulum stress response-mediated plant immunity. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 108:67-80. [PMID: 34374485 DOI: 10.1111/tpj.15425] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 07/09/2021] [Accepted: 07/14/2021] [Indexed: 05/23/2023]
Abstract
Plants deploy various immune receptors to recognize pathogen-derived extracellular signals and subsequently activate the downstream defense response. Recently, increasing evidence indicates that the endoplasmic reticulum (ER) plays a part in the plant defense response, known as ER stress-mediated immunity (ERSI), that halts pathogen infection. However, the mechanism for the ER stress response to signals of pathogen infection remains unclear. Here, we characterized the ER stress response regulator NAC089, which was previously reported to positively regulate programed cell death (PCD), functioning as an ERSI regulator. NAC089 translocated from the ER to the nucleus via the Golgi in response to Phytophthora capsici culture filtrate (CF), which is a mixture of pathogen-associated molecular patterns (PAMPs). Plasma membrane localized co-receptor BRASSINOSTEROID INSENSITIVE 1-associated receptor kinase 1 (BAK1) was required for the CF-mediated translocation of NAC089. The nuclear localization of NAC089, determined by the NAC domain, was essential for immune activation and PCD. Furthermore, NAC089 positively contributed to host resistance against the oomycete pathogen P. capsici and the bacteria pathogen Pseudomonas syringae pv. tomato (Pst) DC3000. We also proved that NAC089-mediated immunity is conserved in Nicotiana benthamiana. Together, we found that PAMP signaling induces the activation of ER stress in plants, and that NAC089 is required for ERSI and plant resistance against pathogens.
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Affiliation(s)
- Gan Ai
- The Key Laboratory of Plant Immunity, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China
| | - Hai Zhu
- The Key Laboratory of Plant Immunity, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China
| | - Xiaowei Fu
- The Key Laboratory of Plant Immunity, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China
| | - Jin Liu
- The Key Laboratory of Plant Immunity, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China
| | - Tianli Li
- The Key Laboratory of Plant Immunity, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yang Cheng
- The Key Laboratory of Plant Immunity, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yang Zhou
- The Key Laboratory of Plant Immunity, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China
| | - Kun Yang
- The Key Laboratory of Plant Immunity, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China
| | - Weiye Pan
- The Key Laboratory of Plant Immunity, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China
| | - Huanxin Zhang
- The Key Laboratory of Plant Immunity, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China
| | - Zishan Wu
- The Key Laboratory of Plant Immunity, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China
| | - Saiyu Dong
- The Key Laboratory of Plant Immunity, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yeqiang Xia
- The Key Laboratory of Plant Immunity, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yuanchao Wang
- The Key Laboratory of Plant Immunity, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China
| | - Ai Xia
- The Key Laboratory of Plant Immunity, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yiming Wang
- The Key Laboratory of Plant Immunity, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China
| | - Daolong Dou
- The Key Laboratory of Plant Immunity, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China
| | - Maofeng Jing
- The Key Laboratory of Plant Immunity, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China
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Nakamura M, Kondo M, Suzuki A, Hirai H, Che FS. Novel Effector RHIFs Identified From Acidovorax avenae Strains N1141 and K1 Play Different Roles in Host and Non-host Plants. FRONTIERS IN PLANT SCIENCE 2021; 12:716738. [PMID: 34421970 PMCID: PMC8377416 DOI: 10.3389/fpls.2021.716738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Accepted: 07/05/2021] [Indexed: 06/13/2023]
Abstract
Plant pathogenic bacteria inject effectors into plant cells using type III secretion systems (T3SS) to evade plant immune systems and facilitate infection. In contrast, plants have evolved defense systems called effector-triggered immunity (ETI) that can detect such effectors during co-evolution with pathogens. The rice-avirulent strain N1141 of the bacterial pathogen Acidovorax avenae causes rice ETI, including hypersensitive response (HR) cell death in a T3SS-dependent manner, suggesting that strain N1141 expresses an ETI-inducing effector. By screening 6,200 transposon-tagged N1141 mutants based on their ability to induce HR cell death, we identified 17 mutants lacking this ability. Sequence analysis and T3SS-mediated intracellular transport showed that a protein called rice HR cell death inducing factor (RHIF) is a candidate effector protein that causes HR cell death in rice. RHIF-disrupted N1141 lacks the ability to induce HR cell death, whereas RHIF expression in this mutant complemented this ability. In contrast, RHIF from rice-virulent strain K1 functions as an ETI inducer in the non-host plant finger millet. Furthermore, inoculation of rice and finger millet with either RHIF-deficient N1141 or K1 strains showed that a deficiency of RHIF genes in both strains results in decreased infectivity toward each the host plants. Collectively, novel effector RHIFs identified from A. avenae strains N1141 and K1 function in establishing infection in host plants and in ETI induction in non-host plants.
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Affiliation(s)
- Minami Nakamura
- Graduate School of Biosciences, Nagahama Institute of Bio-Science and Technology, Nagahama, Japan
| | - Machiko Kondo
- Department of Bio-Science, Nagahama Institute of Bio-Science and Technology, Nagahama, Japan
| | - Aika Suzuki
- Graduate School of Biosciences, Nagahama Institute of Bio-Science and Technology, Nagahama, Japan
| | - Hiroyuki Hirai
- Department of Bio-Science, Nagahama Institute of Bio-Science and Technology, Nagahama, Japan
| | - Fang-Sik Che
- Graduate School of Biosciences, Nagahama Institute of Bio-Science and Technology, Nagahama, Japan
- Department of Bio-Science, Nagahama Institute of Bio-Science and Technology, Nagahama, Japan
- Genome Editing Research Institute, Nagahama Institute of Bio-Science and Technology, Nagahama, Japan
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Schreiber KJ, Hassan JA, Lewis JD. Arabidopsis Abscisic Acid Repressor 1 is a susceptibility hub that interacts with multiple Pseudomonas syringae effectors. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 105:1274-1292. [PMID: 33289145 DOI: 10.1111/tpj.15110] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 11/20/2020] [Accepted: 11/23/2020] [Indexed: 06/12/2023]
Abstract
Pathogens secrete effector proteins into host cells to suppress host immunity and promote pathogen virulence, although many features at the molecular interface of host-pathogen interactions remain to be characterized. In a yeast two-hybrid assay, we found that the Pseudomonas syringae effector HopZ1a interacts with the Arabidopsis transcriptional regulator Abscisic Acid Repressor 1 (ABR1). Further analysis revealed that ABR1 interacts with multiple P. syringae effectors, suggesting that it may be targeted as a susceptibility hub. Indeed, loss-of-function abr1 mutants exhibit reduced susceptibility to a number of P. syringae strains. The ABR1 protein comprises a conserved APETALA2 (AP2) domain flanked by long regions of predicted structural disorder. We verified the DNA-binding activity of the AP2 domain and demonstrated that the disordered domains act redundantly to enhance DNA binding and to facilitate transcriptional activation by ABR1. Finally, we compared gene expression profiles from wild-type and abr1 plants following inoculation with P. syringae, which suggested that the reduced susceptibility of abr1 mutants is due to the loss of a virulence target rather than an enhanced immune response. These data highlight ABR1 as a functionally important component at the host-pathogen interface.
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Affiliation(s)
- Karl J Schreiber
- Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, CA, USA
| | - Jana A Hassan
- Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, CA, USA
| | - Jennifer D Lewis
- Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, CA, USA
- United States Department of Agriculture, Plant Gene Expression Center, Albany, CA, USA
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37
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Meisrimler C, Allan C, Eccersall S, Morris RJ. Interior design: how plant pathogens optimize their living conditions. THE NEW PHYTOLOGIST 2021; 229:2514-2524. [PMID: 33098094 PMCID: PMC7898814 DOI: 10.1111/nph.17024] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 10/14/2020] [Indexed: 06/11/2023]
Abstract
Pathogens use effectors to suppress host defence mechanisms, promote the derivation of nutrients, and facilitate infection within the host plant. Much is now known about effectors that target biotic pathways, particularly those that interfere with plant innate immunity. By contrast, an understanding of how effectors manipulate nonimmunity pathways is only beginning to emerge. Here, we focus on exciting new insights into effectors that target abiotic stress adaptation pathways, tampering with key functions within the plant to promote colonization. We critically assess the role of various signalling agents in linking different pathways upon perturbation by pathogen effectors. Additionally, this review provides a summary of currently known bacterial, fungal, and oomycete pathogen effectors that induce biotic and abiotic stress responses in the plant, as a first step towards establishing a comprehensive picture for linking effector targets to pathogenic lifestyles.
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Affiliation(s)
| | - Claudia Allan
- School of Biological ScienceUniversity of CanterburyPrivate Bag 4800Christchurch8041New Zealand
| | - Sophie Eccersall
- School of Biological ScienceUniversity of CanterburyPrivate Bag 4800Christchurch8041New Zealand
| | - Richard J Morris
- Computational and Systems BiologyJohn Innes CentreNorwichNR4 7UHUK
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38
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Falak N, Imran QM, Hussain A, Yun BW. Transcription Factors as the "Blitzkrieg" of Plant Defense: A Pragmatic View of Nitric Oxide's Role in Gene Regulation. Int J Mol Sci 2021; 22:E522. [PMID: 33430258 PMCID: PMC7825681 DOI: 10.3390/ijms22020522] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 12/30/2020] [Accepted: 01/05/2021] [Indexed: 12/24/2022] Open
Abstract
Plants are in continuous conflict with the environmental constraints and their sessile nature demands a fine-tuned, well-designed defense mechanism that can cope with a multitude of biotic and abiotic assaults. Therefore, plants have developed innate immunity, R-gene-mediated resistance, and systemic acquired resistance to ensure their survival. Transcription factors (TFs) are among the most important genetic components for the regulation of gene expression and several other biological processes. They bind to specific sequences in the DNA called transcription factor binding sites (TFBSs) that are present in the regulatory regions of genes. Depending on the environmental conditions, TFs can either enhance or suppress transcriptional processes. In the last couple of decades, nitric oxide (NO) emerged as a crucial molecule for signaling and regulating biological processes. Here, we have overviewed the plant defense system, the role of TFs in mediating the defense response, and that how NO can manipulate transcriptional changes including direct post-translational modifications of TFs. We also propose that NO might regulate gene expression by regulating the recruitment of RNA polymerase during transcription.
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Affiliation(s)
- Noreen Falak
- Laboratory of Plant Functional Genomics, School of Applied Biosciences, Kyungpook National University, Daegu 702-701, Korea; (N.F.); (Q.M.I.)
| | - Qari Muhammad Imran
- Laboratory of Plant Functional Genomics, School of Applied Biosciences, Kyungpook National University, Daegu 702-701, Korea; (N.F.); (Q.M.I.)
- Department of Medical Biochemistry and Biophysics, Umea University, 90187 Umea, Sweden
| | - Adil Hussain
- Department of Agriculture, Abdul Wali Khan University, Mardan, Khyber Pakhtunkhwa 23200, Pakistan;
| | - Byung-Wook Yun
- Laboratory of Plant Functional Genomics, School of Applied Biosciences, Kyungpook National University, Daegu 702-701, Korea; (N.F.); (Q.M.I.)
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Wang J, Dhroso A, Liu X, Baum TJ, Hussey RS, Davis EL, Wang X, Korkin D, Mitchum MG. Phytonematode peptide effectors exploit a host post-translational trafficking mechanism to the ER using a novel translocation signal. THE NEW PHYTOLOGIST 2021; 229:563-574. [PMID: 32569394 DOI: 10.1111/nph.16765] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 06/02/2020] [Indexed: 05/26/2023]
Abstract
Cyst nematodes induce a multicellular feeding site within roots called a syncytium. It remains unknown how root cells are primed for incorporation into the developing syncytium. Furthermore, it is unclear how CLAVATA3/EMBRYO SURROUNDING REGION (CLE) peptide effectors secreted into the cytoplasm of the initial feeding cell could have an effect on plant cells so distant from where the nematode is feeding as the syncytium expands. Here we describe a novel translocation signal within nematode CLE effectors that is recognized by plant cell secretory machinery to redirect these peptides from the cytoplasm to the apoplast of plant cells. We show that the translocation signal is functionally conserved across CLE effectors identified in nematode species spanning three genera and multiple plant species, operative across plant cell types, and can traffic other unrelated small peptides from the cytoplasm to the apoplast of host cells via a previously unknown post-translational mechanism of endoplasmic reticulum (ER) translocation. Our results uncover a mechanism of effector trafficking that is unprecedented in any plant pathogen to date, andthey illustrate how phytonematodes can deliver effector proteins into host cells and then hijack plant cellular processes for their export back out of the cell to function as external signaling molecules to distant cells.
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Affiliation(s)
- Jianying Wang
- Division of Plant Sciences and Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA
| | - Andi Dhroso
- Department of Computer Science and Bioinformatics and Computational Biology Program, Worcester Polytechnic Institute, Worcester, MA, 01609, USA
| | - Xunliang Liu
- Department of Plant Pathology and Institute of Plant Breeding, Genetics, and Genomics, Center for Applied Genetic Technologies, University of Georgia, Athens, GA, 30602, USA
| | - Thomas J Baum
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, IA, 50011, USA
| | - Richard S Hussey
- Department of Plant Pathology, University of Georgia, Athens, GA, 30602, USA
| | - Eric L Davis
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC, 27695, USA
| | - Xiaohong Wang
- Robert W. Holley Center for Agriculture and Health, US Department of Agriculture, Agricultural Research Service and School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, USA
| | - Dmitry Korkin
- Department of Computer Science and Bioinformatics and Computational Biology Program, Worcester Polytechnic Institute, Worcester, MA, 01609, USA
| | - Melissa G Mitchum
- Division of Plant Sciences and Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA
- Department of Plant Pathology and Institute of Plant Breeding, Genetics, and Genomics, Center for Applied Genetic Technologies, University of Georgia, Athens, GA, 30602, USA
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Zhang X, Zhao M, Jiang J, Yang L, Yang Y, Yang S, Walcott R, Qiu D, Zhao T. Identification and Functional Analysis of AopN, an Acidovorax Citrulli Effector that Induces Programmed Cell Death in Plants. Int J Mol Sci 2020; 21:E6050. [PMID: 32842656 PMCID: PMC7504669 DOI: 10.3390/ijms21176050] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 08/01/2020] [Accepted: 08/18/2020] [Indexed: 01/23/2023] Open
Abstract
Bacterial fruit blotch (BFB), caused by Acidovorax citrulli, seriously affects watermelon and other cucurbit crops, resulting in significant economic losses. However, the pathogenicity mechanism of A. citrulli is not well understood. Plant pathogenic bacteria often suppress the plant immune response by secreting effector proteins. Thus, identifying A. citrulli effector proteins and determining their functions may improve our understanding of the underlying pathogenetic mechanisms. In this study, a novel effector, AopN, which is localized on the cell membrane of Nicotiana benthamiana, was identified. The functional analysis revealed that AopN significantly inhibited the flg22-induced reactive oxygen species burst. AopN induced a programmed cell death (PCD) response. Unlike its homologous protein, the ability of AopN to induce PCD was dependent on two motifs of unknown functions (including DUP4129 and Cpta_toxin), but was not dependent on LXXLL domain. More importantly, the virulence of the aopN mutant of A. citrulli in N. benthamiana significantly decreased, indicating that it was a core effector. Further analysis revealed that AopN interacted with watermelon ClHIPP and ClLTP, which responds to A. citrulli strain Aac5 infection at the transcription level. Collectively, these findings indicate that AopN suppresses plant immunity and activates the effector-triggered immunity pathway.
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Affiliation(s)
- Xiaoxiao Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (X.Z.); (J.J.); (L.Y.); (Y.Y.); (D.Q.)
| | - Mei Zhao
- Department of Plant Pathology, University of Georgia, Athens, GA 30602, USA; (M.Z.); (R.W.)
| | - Jie Jiang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (X.Z.); (J.J.); (L.Y.); (Y.Y.); (D.Q.)
| | - Linlin Yang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (X.Z.); (J.J.); (L.Y.); (Y.Y.); (D.Q.)
| | - Yuwen Yang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (X.Z.); (J.J.); (L.Y.); (Y.Y.); (D.Q.)
| | - Shanshan Yang
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100193, China;
| | - Ron Walcott
- Department of Plant Pathology, University of Georgia, Athens, GA 30602, USA; (M.Z.); (R.W.)
| | - Dewen Qiu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (X.Z.); (J.J.); (L.Y.); (Y.Y.); (D.Q.)
| | - Tingchang Zhao
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (X.Z.); (J.J.); (L.Y.); (Y.Y.); (D.Q.)
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Genome-Wide Analysis of the Role of NAC Family in Flower Development and Abiotic Stress Responses in Cleistogenes songorica. Genes (Basel) 2020; 11:genes11080927. [PMID: 32806602 PMCID: PMC7464430 DOI: 10.3390/genes11080927] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 08/08/2020] [Accepted: 08/11/2020] [Indexed: 11/19/2022] Open
Abstract
Plant-specific NAC (NAM, ATAF, CUC) transcription factor (TF) family plays important roles in biological processes such as plant growth and response to stress. Nevertheless, no information is known about NAC TFs in Cleistogenes songorica, a prominent xerophyte desert grass in northwestern China. In this study, 162 NAC genes were found from the Cleistogenes songorica genome, among which 156 C. songoricaNAC (CsNAC) genes (96.3%) were mapped onto 20 chromosomes. The phylogenetic tree constructed by CsNAC and rice NAC TFs can be separated into 14 subfamilies. Syntenic and Ka/Ks analyses showed that CsNACs were primarily expanded by genomewide replication events, and purifying selection was the primary force driving the evolution of CsNAC family genes. The CsNAC gene expression profiles showed that 36 CsNAC genes showed differential expression between cleistogamous (CL) and chasmogamous (CH) flowers. One hundred and two CsNAC genes showed differential expression under heat, cold, drought, salt and ABA treatment. Twenty-three CsNAC genes were commonly differentially expressed both under stress responses and during dimorphic floret development. Gene Ontology (GO) annotation, coexpression network and qRT-PCR tests revealed that these CsNAC genes may simultaneously regulate dimorphic floret development and the response to stress. Our results may help to characterize the NAC transcription factors in C. songorica and provide new insights into the functional research and application of the NAC family in crop improvement, especially in dimorphic floret plants.
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Zhou B, Benbow HR, Brennan CJ, Arunachalam C, Karki SJ, Mullins E, Feechan A, Burke JI, Doohan FM. Wheat Encodes Small, Secreted Proteins That Contribute to Resistance to Septoria Tritici Blotch. Front Genet 2020; 11:469. [PMID: 32477410 PMCID: PMC7235427 DOI: 10.3389/fgene.2020.00469] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 04/16/2020] [Indexed: 11/23/2022] Open
Abstract
During plant-pathogen interactions, pathogens secrete many rapidly evolving, small secreted proteins (SSPs) that can modify plant defense and permit pathogens to colonize plant tissue. The fungal pathogen Zymoseptoria tritici is the causal agent of Septoria tritici blotch (STB), one of the most important foliar diseases of wheat, globally. Z. tritici is a strictly apoplastic pathogen that can secrete numerous proteins into the apoplast of wheat leaves to promote infection. We sought to determine if, during STB infection, wheat also secretes small proteins into the apoplast to mediate the recognition of pathogen proteins and/or induce defense responses. To explore this, we developed an SSP-discovery pipeline to identify small, secreted proteins from wheat genomic data. Using this pipeline, we identified 6,998 SSPs, representing 2.3% of all proteins encoded by the wheat genome. We then mined a microarray dataset, detailing a resistant and susceptible host response to STB, and identified 141 Z. tritici- responsive SSPs, representing 4.7% of all proteins encoded by Z. tritici - responsive genes. We demonstrate that a subset of these SSPs have a functional signal peptide and can interact with Z. tritici SSPs. Transiently silencing two of these wheat SSPs using virus-induced gene silencing (VIGS) shows an increase in susceptibility to STB, confirming their role in defense against Z. tritici.
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Affiliation(s)
- Binbin Zhou
- UCD School of Biology and Environmental Science, UCD Earth Institute, UCD O’Brien Centre for Science (East), University College Dublin, Dublin, Ireland
| | - Harriet R. Benbow
- UCD School of Biology and Environmental Science, UCD Earth Institute, UCD O’Brien Centre for Science (East), University College Dublin, Dublin, Ireland
| | - Ciarán J. Brennan
- UCD School of Biology and Environmental Science, UCD Earth Institute, UCD O’Brien Centre for Science (East), University College Dublin, Dublin, Ireland
| | - Chanemougasoundharam Arunachalam
- UCD School of Biology and Environmental Science, UCD Earth Institute, UCD O’Brien Centre for Science (East), University College Dublin, Dublin, Ireland
| | - Sujit J. Karki
- UCD School of Agriculture and Food Science, University College Dublin, Dublin, Ireland
| | - Ewen Mullins
- Department of Crop Science, Teagasc, Carlow, Ireland
| | - Angela Feechan
- UCD School of Agriculture and Food Science, University College Dublin, Dublin, Ireland
| | - James I. Burke
- UCD School of Agriculture and Food Science, University College Dublin, Dublin, Ireland
| | - Fiona M. Doohan
- UCD School of Biology and Environmental Science, UCD Earth Institute, UCD O’Brien Centre for Science (East), University College Dublin, Dublin, Ireland
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43
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Genetic Network between Leaf Senescence and Plant Immunity: Crucial Regulatory Nodes and New Insights. PLANTS 2020; 9:plants9040495. [PMID: 32294898 PMCID: PMC7238237 DOI: 10.3390/plants9040495] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 02/17/2020] [Accepted: 02/18/2020] [Indexed: 12/30/2022]
Abstract
Leaf senescence is an essential physiological process that is accompanied by the remobilization of nutrients from senescent leaves to young leaves or other developing organs. Although leaf senescence is a genetically programmed process, it can be induced by a wide variety of biotic and abiotic factors. Accumulating studies demonstrate that senescence-associated transcription factors (Sen-TFs) play key regulatory roles in controlling the initiation and progression of leaf senescence process. Interestingly, recent functional studies also reveal that a number of Sen-TFs function as positive or negative regulators of plant immunity. Moreover, the plant hormone salicylic acid (SA) and reactive oxygen species (ROS) have been demonstrated to be key signaling molecules in regulating leaf senescence and plant immunity, suggesting that these two processes share similar or common regulatory networks. However, the interactions between leaf senescence and plant immunity did not attract sufficient attention to plant scientists. Here, we review the regulatory roles of SA and ROS in biotic and abiotic stresses, as well as the cross-talks between SA/ROS and other hormones in leaf senescence and plant immunity, summarize the transcriptional controls of Sen-TFs on SA and ROS signal pathways, and analyze the cross-regulation between senescence and immunity through a broad literature survey. In-depth understandings of the cross-regulatory mechanisms between leaf senescence and plant immunity will facilitate the cultivation of high-yield and disease-resistant crops through a molecular breeding strategy.
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44
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Collmer A. James Robert Alfano, A Giant in Phytopathogenic Bacteria Effector Biology. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2020; 33:377-381. [PMID: 31990622 DOI: 10.1094/mpmi-12-19-0354-cr] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The worldwide molecular plant-microbe interactions research community was significantly diminished in November 2019 by the death of James "Jim" Robert Alfano at age 56. Jim was a giant in our field, who gained key insights into plant pathogenesis using the model bacterial pathogen Pseudomonas syringae. As a mentor, collaborator, and, above all, a friend, I know Jim's many dimensions and accomplishments and, sadly, the depth of loss being felt by the many people around the world who were touched by him. In tracing the path of Jim's career, I will emphasize the historical context and impact of his advances and, finally, the essence of the person we will so miss.
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Affiliation(s)
- Alan Collmer
- School of Integrative Plant Science, Section of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, NY 14853, U.S.A
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45
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Collum TD, Stone AL, Sherman DJ, Rogers EE, Dardick C, Culver JN. Translatome Profiling of Plum Pox Virus-Infected Leaves in European Plum Reveals Temporal and Spatial Coordination of Defense Responses in Phloem Tissues. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2020; 33:66-77. [PMID: 31347973 DOI: 10.1094/mpmi-06-19-0152-fi] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Plum pox virus (PPV) is the causative agent of sharka, a devastating disease of stone fruits including peaches, apricots, and plums. PPV infection levels and associated disease symptoms can vary greatly, depending upon the virus strain, host species, or cultivar as well as developmental age of the infected tissues. For example, peaches often exhibit mild symptoms in leaves and fruit while European plums typically display severe chlorotic rings. Systemic virus spread into all host tissues occurs via the phloem, a process that is poorly understood in perennial plant species that undergo a period of dormancy and must annually renew phloem tissues. Currently, little is known about how phloem tissues respond to virus infection. Here, we used translating ribosome affinity purification followed by RNA sequencing to identify phloem- and nonphloem-specific gene responses to PPV infection during leaf development in European plum (Prunus domestica L.). Results showed that, during secondary leaf morphogenesis (4- and 6-week-old leaves), the phloem had a disproportionate response to PPV infection with two- to sixfold more differentially expressed genes (DEGs) in phloem than nonphloem tissues, despite similar levels of viral transcripts. In contrast, in mature 12-week-old leaves, virus transcript levels dropped significantly in phloem tissues but not in nonphloem tissues. This drop in virus transcripts correlated with an 18-fold drop in phloem-specific DEGs. Furthermore, genes associated with defense responses including RNA silencing were spatially coordinated in response to PPV accumulation and were specifically induced in phloem tissues at 4 to 6 weeks. Combined, these findings highlight the temporal and spatial dynamics of leaf tissue responses to virus infection and reveal the importance of phloem responses within a perennial host.
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Affiliation(s)
- Tamara D Collum
- Institute for Bioscience and Biotechnology Research, College Park, MD, U.S.A
| | - Andrew L Stone
- USDA, Agricultural Research Service, Foreign Disease-Weed Science Research Unit, Frederick, MD, U.S.A
| | - Diana J Sherman
- USDA, Agricultural Research Service, Foreign Disease-Weed Science Research Unit, Frederick, MD, U.S.A
| | - Elizabeth E Rogers
- USDA, Agricultural Research Service, Foreign Disease-Weed Science Research Unit, Frederick, MD, U.S.A
| | - Christopher Dardick
- USDA, Agricultural Research Service, Appalachian Fruit Research Station, Kearneysville, WV, U.S.A
| | - James N Culver
- Institute for Bioscience and Biotechnology Research, College Park, MD, U.S.A
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD, U.S.A
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46
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Chen W, Li Y, Yan R, Xu L, Ren L, Liu F, Zeng L, Yang H, Chi P, Wang X, Chen K, Ma D, Fang X. Identification and Characterization of Plasmodiophora brassicae Primary Infection Effector Candidates that Suppress or Induce Cell Death in Host and Nonhost Plants. PHYTOPATHOLOGY 2019; 109:1689-1697. [PMID: 31188071 DOI: 10.1094/phyto-02-19-0039-r] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Clubroot caused by Plasmodiophora brassicaeis one of the most important diseases in cruciferous crops. The recognition of P. brassicae by host plants is thought to occur at the primary infection stage, but the underlying mechanism remains unclear. Secretory proteins as effector candidates play critical roles in the recognition of pathogens and the interactions between pathogens and hosts. In this study, 33 P. brassicae secretory proteins expressed during primary infection were identified through transcriptome, secretory protein prediction, and yeast signal sequence trap analyses. Furthermore, the proteins that could suppress or induce cell death were screened through an Agrobacterium-mediated plant virus transient expression system and a protoplast transient expression system. Two secretory proteins, PBCN_002550 and PBCN_005499, were found to be capable of inducing cell death associated with H2O2 accumulation and electrolyte leakage in Nicotiana benthamiana. Moreover, PBCN_002550 could also induce cell death in Chinese cabbage. In addition, 24 of the remaining 31 tested secretory proteins could suppress mouse Bcl-2-associated X protein-induced cell death, and 28 proteins could suppress PBCN_002550-induced cell death.
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Affiliation(s)
- Wang Chen
- Oil Crops Research Institute of Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetics Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Wuhan 430062, Hubei, China
| | - Yan Li
- Oil Crops Research Institute of Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetics Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Wuhan 430062, Hubei, China
| | - Ruibin Yan
- Oil Crops Research Institute of Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetics Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Wuhan 430062, Hubei, China
| | - Li Xu
- Oil Crops Research Institute of Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetics Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Wuhan 430062, Hubei, China
| | - Li Ren
- Oil Crops Research Institute of Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetics Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Wuhan 430062, Hubei, China
| | - Fan Liu
- Oil Crops Research Institute of Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetics Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Wuhan 430062, Hubei, China
| | - Lingyi Zeng
- Oil Crops Research Institute of Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetics Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Wuhan 430062, Hubei, China
| | - Huan Yang
- Oil Crops Research Institute of Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetics Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Wuhan 430062, Hubei, China
| | - Peng Chi
- Oil Crops Research Institute of Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetics Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Wuhan 430062, Hubei, China
| | - Xiuzhen Wang
- Oil Crops Research Institute of Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetics Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Wuhan 430062, Hubei, China
| | - Kunrong Chen
- Oil Crops Research Institute of Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetics Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Wuhan 430062, Hubei, China
| | - Dongfang Ma
- Hubei Collaborative Innovation Center for Grain Industry, Yangtze University, Jingzhou 434025, China
| | - Xiaoping Fang
- Oil Crops Research Institute of Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetics Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Wuhan 430062, Hubei, China
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47
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Meisrimler C, Pelgrom AJE, Oud B, Out S, Van den Ackerveken G. Multiple downy mildew effectors target the stress-related NAC transcription factor LsNAC069 in lettuce. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2019; 99:1098-1115. [PMID: 31077456 PMCID: PMC9545932 DOI: 10.1111/tpj.14383] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 04/04/2019] [Accepted: 04/17/2019] [Indexed: 05/22/2023]
Abstract
To cause disease in lettuce, the biotrophic oomycete Bremia lactucae secretes potential RxLR effector proteins. Here we report the discovery of an effector-target hub consisting of four B. lactucae effectors and one lettuce protein target by a yeast-two-hybrid (Y2H) screening. Interaction of the lettuce tail-anchored NAC transcription factor, LsNAC069, with B. lactucae effectors does not require the N-terminal NAC domain but depends on the C-terminal region including the transmembrane domain. Furthermore, in Y2H experiments, B. lactucae effectors interact with Arabidopsis and potato tail-anchored NACs, suggesting that they are conserved effector targets. Transient expression of RxLR effector proteins BLR05 and BLR09 and their target LsNAC069 in planta revealed a predominant localization to the endoplasmic reticulum. Phytophthora capsici culture filtrate and polyethylene glycol treatment induced relocalization to the nucleus of a stabilized LsNAC069 protein, lacking the NAC-domain (LsNAC069ΔNAC ). Relocalization was significantly reduced in the presence of the Ser/Cys-protease inhibitor TPCK indicating proteolytic cleavage of LsNAC069 allows for relocalization. Co-expression of effectors with LsNAC069ΔNAC reduced its nuclear accumulation. Surprisingly, LsNAC069 silenced lettuce lines had decreased LsNAC069 transcript levels but did not show significantly altered susceptibility to B. lactucae. In contrast, LsNAC069 silencing increased resistance to Pseudomonas cichorii bacteria and reduced wilting effects under moderate drought stress, indicating a broad role of LsNAC069 in abiotic and biotic stress responses.
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Affiliation(s)
- Claudia‐Nicole Meisrimler
- Plant–Microbe InteractionsDepartment of BiologyUtrecht UniversityPadualaan 83584 CHUtrechtthe Netherlands
- University of CanterburyIlamPrivate Bag 4800Christchurch8041New Zealand
| | - Alexandra J. E. Pelgrom
- Plant–Microbe InteractionsDepartment of BiologyUtrecht UniversityPadualaan 83584 CHUtrechtthe Netherlands
| | - Bart Oud
- Enza ZadenHaling 1‐EEnkhuizen1602 DBthe Netherlands
| | - Suzan Out
- Enza ZadenHaling 1‐EEnkhuizen1602 DBthe Netherlands
| | - Guido Van den Ackerveken
- Plant–Microbe InteractionsDepartment of BiologyUtrecht UniversityPadualaan 83584 CHUtrechtthe Netherlands
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48
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Xie Y, Shao X, Deng X. Regulation of type III secretion system inPseudomonas syringae. Environ Microbiol 2019; 21:4465-4477. [DOI: 10.1111/1462-2920.14779] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 08/10/2019] [Accepted: 08/11/2019] [Indexed: 12/11/2022]
Affiliation(s)
- Yingpeng Xie
- Department of Biomedical SciencesCity University of Hong Kong Kowloon Tong Hong Kong SAR 999077 China
| | - Xiaolong Shao
- Department of Biomedical SciencesCity University of Hong Kong Kowloon Tong Hong Kong SAR 999077 China
| | - Xin Deng
- Department of Biomedical SciencesCity University of Hong Kong Kowloon Tong Hong Kong SAR 999077 China
- Shenzhen Research InstituteCity University of Hong Kong Shenzhen 518057 China
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49
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Qi G, Chen J, Chang M, Chen H, Hall K, Korin J, Liu F, Wang D, Fu ZQ. Pandemonium Breaks Out: Disruption of Salicylic Acid-Mediated Defense by Plant Pathogens. MOLECULAR PLANT 2018; 11:1427-1439. [PMID: 30336330 DOI: 10.1016/j.molp.2018.10.002] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 09/30/2018] [Accepted: 10/09/2018] [Indexed: 05/26/2023]
Abstract
Salicylic acid (SA) or 2-hydroxybenoic acid is a phenolic plant hormone that plays an essential role in plant defense against biotrophic and semi-biotrophic pathogens. In Arabidopsis, SA is synthesized from chorismate in the chloroplast through the ICS1 (isochorismate synthase I) pathway during pathogen infection. The transcription co-activator NPR1 (Non-Expresser of Pathogenesis-Related Gene 1), as the master regulator of SA signaling, interacts with transcription factors to induce the expression of anti-microbial PR (Pathogenesis-Related) genes. To establish successful infections, plant bacterial, oomycete, fungal, and viral pathogens have evolved at least three major strategies to disrupt SA-mediated defense. The first strategy is to reduce SA accumulation directly by converting SA into its inactive derivatives. The second strategy is to interrupt SA biosynthesis by targeting the ICS1 pathway. In the third major strategy, plant pathogens deploy different mechanisms to interfere with SA downstream signaling. The wide array of strategies deployed by plant pathogens highlights the crucial role of disruption of SA-mediated plant defense in plant pathogenesis. A deeper understanding of this topic will greatly expand our knowledge of how plant pathogens cause diseases and consequently pave the way for the development of more effective ways to control these diseases.
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Affiliation(s)
- Guang Qi
- State Key Laboratory of Wheat and Maize Crop Science and College of Agronomy, Henan Agricultural University, Zhengzhou 450002, China; Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Jian Chen
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Nanjing 210014, China; Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Ming Chang
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Nanjing 210014, China; Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Huan Chen
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Nanjing 210014, China; Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Katherine Hall
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - John Korin
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Fengquan Liu
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Nanjing 210014, China.
| | - Daowen Wang
- State Key Laboratory of Wheat and Maize Crop Science and College of Agronomy, Henan Agricultural University, Zhengzhou 450002, China.
| | - Zheng Qing Fu
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA.
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50
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Andersen EJ, Ali S, Byamukama E, Yen Y, Nepal MP. Disease Resistance Mechanisms in Plants. Genes (Basel) 2018; 9:E339. [PMID: 29973557 PMCID: PMC6071103 DOI: 10.3390/genes9070339] [Citation(s) in RCA: 154] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 06/29/2018] [Indexed: 12/24/2022] Open
Abstract
Plants have developed a complex defense system against diverse pests and pathogens. Once pathogens overcome mechanical barriers to infection, plant receptors initiate signaling pathways driving the expression of defense response genes. Plant immune systems rely on their ability to recognize enemy molecules, carry out signal transduction, and respond defensively through pathways involving many genes and their products. Pathogens actively attempt to evade and interfere with response pathways, selecting for a decentralized, multicomponent immune system. Recent advances in molecular techniques have greatly expanded our understanding of plant immunity, largely driven by potential application to agricultural systems. Here, we review the major plant immune system components, state of the art knowledge, and future direction of research on plant⁻pathogen interactions. In our review, we will discuss how the decentralization of plant immune systems have provided both increased evolutionary opportunity for pathogen resistance, as well as additional mechanisms for pathogen inhibition of such defense responses. We conclude that the rapid advances in bioinformatics and molecular biology are driving an explosion of information that will advance agricultural production and illustrate how complex molecular interactions evolve.
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Affiliation(s)
- Ethan J Andersen
- Department of Biology and Microbiology, South Dakota State University, Brookings, 57007 SD, USA.
| | - Shaukat Ali
- Department of Agronomy, Horticulture, and Plant Science, South Dakota State University, Brookings, 57007 SD, USA.
| | - Emmanuel Byamukama
- Department of Agronomy, Horticulture, and Plant Science, South Dakota State University, Brookings, 57007 SD, USA.
| | - Yang Yen
- Department of Biology and Microbiology, South Dakota State University, Brookings, 57007 SD, USA.
| | - Madhav P Nepal
- Department of Biology and Microbiology, South Dakota State University, Brookings, 57007 SD, USA.
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