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Li Y, Qu X, Yang W, Wu Q, Wang X, Jiang Q, Ma J, Zhang Y, Qi P, Chen G, Zheng Y, Wang X, Wei Y, Xu Q. A fungal pathogen suppresses host leaf senescence to increase infection. Nat Commun 2025; 16:2864. [PMID: 40128252 PMCID: PMC11933281 DOI: 10.1038/s41467-025-58277-5] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2024] [Accepted: 03/14/2025] [Indexed: 03/26/2025] Open
Abstract
Phytopathogens such as Puccinia striiformis f. sp. tritici (Pst) induce pigment retention at pathogen infection sites. Although pigment retention is commonly observed in diverse pathosystems, its underlying physiological mechanism remains largely unclear. Herein, we identify and characterize a wheat leaf senescence gene, TaSGR1, which enhances resistance against Pst by promoting leaf senescence and H2O2 accumulation while inhibiting photosynthesis. Knockout of TaSGR1 (STAYGREEN) in wheat increases pigment retention and plant susceptibility. Pst_TTP1 (TaTrx-Targeting Protein 1), a secreted rust fungal effector critical for Pst virulence, binds to the plastidial thioredoxin TaTrx (Thioredoxin), preventing its translocation into chloroplasts. Within the chloroplasts, TaTrx catalyzes the transformation of TaSGR1 oligomers into monomers. These TaSGR1 monomers accumulate in the chloroplasts, accelerating leaf senescence, H2O2 accumulation, and cell death. The inhibition of this oligomer-to-monomer transformation, caused by the failure of TaTrx to enter the chloroplast due to Pst_TTP1, impairs plant resistance against Pst. Overall, our study reveals the suppression of redox signaling cascade that catalyzes the transformation of TaSGR1 oligomers into monomers within chloroplasts and the inhibition of leaf chlorosis by rust effectors as key mechanisms underlying disease susceptibility.
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Affiliation(s)
- Yue Li
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Chengdu, Sichuan, China
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Xiangru Qu
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Chengdu, Sichuan, China
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Wenjuan Yang
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Chengdu, Sichuan, China
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Qin Wu
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Chengdu, Sichuan, China
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Xiaodong Wang
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, China
| | - Qiantao Jiang
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Chengdu, Sichuan, China
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Jian Ma
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Chengdu, Sichuan, China
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Yazhou Zhang
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Chengdu, Sichuan, China
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Pengfei Qi
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Chengdu, Sichuan, China
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Guoyue Chen
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Chengdu, Sichuan, China
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Youliang Zheng
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Chengdu, Sichuan, China
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Xiaojie Wang
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, China.
| | - Yuming Wei
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Chengdu, Sichuan, China.
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan, China.
| | - Qiang Xu
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Chengdu, Sichuan, China.
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan, China.
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Li Z, Wu R, Guo F, Wang Y, Nick P, Wang X. Advances in the molecular mechanism of grapevine resistance to fungal diseases. MOLECULAR HORTICULTURE 2025; 5:1. [PMID: 39743511 DOI: 10.1186/s43897-024-00119-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2024] [Accepted: 10/14/2024] [Indexed: 01/04/2025]
Abstract
Grapevine is an important economic fruit tree worldwide, but grape production has been plagued by a vast number of fungal diseases, which affect tree vigor and the quality and yield of berries. To seek remedies for such issues, researchers have always been committed to conventional and biotechnological breeding. In recent years, increasing progress has been made in elucidating the molecular mechanisms of grape-pathogenic fungi interactions and resistance regulation. Here, we summarize the current knowledge on the molecular basis of grapevine resistance to fungal diseases, including fungal effector-mediated susceptibility and resistance, resistant regulatory networks in grapevine, innovative approaches of genetic transformation, and strategies to improve grape resistance. Understanding the molecular basis is important for exploring and accurately regulating grape resistance to fungal diseases.
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Affiliation(s)
- Zhi Li
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, China
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, China
| | - Ronghui Wu
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, China
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, China
| | - Fangying Guo
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, China
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, China
| | - Yuejin Wang
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, China
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, China
| | - Peter Nick
- Molecular Cell Biology, Botanical Institute, Karlsruhe Institute of Technology, Karlsruhe, Germany.
| | - Xiping Wang
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, College of Horticulture, Northwest A&F University, Yangling, Shaanxi, China.
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, China.
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3
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Jin M, Hu S, Wu Q, Feng X, Zhang Y, Jiang Q, Ma J, Qi P, Chen G, Jiang Y, Zheng Y, Wei Y, Xu Q. An effector protein of Fusarium graminearum targets chloroplasts and suppresses cyclic photosynthetic electron flow. PLANT PHYSIOLOGY 2024; 196:2422-2436. [PMID: 39365766 DOI: 10.1093/plphys/kiae538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2024] [Accepted: 09/09/2024] [Indexed: 10/06/2024]
Abstract
Chloroplasts are important photosynthetic organelles that regulate plant immunity, growth, and development. However, the role of fungal secretory proteins in linking the photosystem to the plant immune system remains largely unknown. Our systematic characterization of 17 chloroplast-targeting secreted proteins of Fusarium graminearum indicated that Fg03600 is an important virulence factor. Fg03600 translocation into plant cells and accumulation in chloroplasts depended on its chloroplast transit peptide. Fg03600 interacted with the wheat (Triticum aestivum L.) proton gradient regulation 5-like protein 1 (TaPGRL1), a part of the cyclic photosynthetic electron transport chain, and promoted TaPGRL1 homo-dimerization. Interestingly, TaPGRL1 also interacted with ferredoxin (TaFd), a chloroplast ferredoxin protein that transfers cyclic electrons to TaPGRL1. TaFd competed with Fg03600 for binding to the same region of TaPGRL1. Fg03600 expression in plants decreased cyclic electron flow (CEF) but increased the production of chloroplast-derived reactive oxygen species (ROS). Stably silenced TaPGRL1 impaired resistance to Fusarium head blight (FHB) and disrupted CEF. Overall, Fg03600 acts as a chloroplast-targeting effector to suppress plant CEF and increase photosynthesis-derived ROS for FHB development at the necrotrophic stage by promoting homo-dimeric TaPGRL1 or competing with TaFd for TaPGRL1 binding.
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Affiliation(s)
- Minxia Jin
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Su Hu
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Qin Wu
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Xiangran Feng
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Yazhou Zhang
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Qiantao Jiang
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Jian Ma
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Pengfei Qi
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Guoyue Chen
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Yunfeng Jiang
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Youliang Zheng
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Yuming Wei
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
| | - Qiang Xu
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China
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4
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Xiang Y, Yuan H, Mao M, Hu Q, Dong Y, Wang L, Wu B, Luo Z, Li L. Reciprocal inhibition of autophagy and Botrytis cinerea-induced programmed cell death in 'Shine Muscat' grapes. Food Chem 2024; 460:140512. [PMID: 39047497 DOI: 10.1016/j.foodchem.2024.140512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Revised: 06/16/2024] [Accepted: 07/16/2024] [Indexed: 07/27/2024]
Abstract
Botrytis cinerea causes gray mold, decreasing the quality of table grapes. The berry response to B. cinerea infection was explored in present study, focusing on the relationship between presence of autophagy and programmed cell death (PCD). Results demonstrated B. cinerea infection decreased cell viability, triggering cell death, possibly resulting in PCD occurrence. It was further verified by increased terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL)-positive nuclei, heightened caspase 3-like and caspase 9-like protease activity, and elevated expression of metacaspase genes. Additionally, autophagy was indicated by the increased VvATG expression and autophagosome formation. Notably, the autophagy activator rapamycin reduced TUNEL-positive nuclei, whereas the autophagy inhibitor 3-methyladenine increased caspase 9-like protease activity. The PCD activator C2-ceramide inhibited autophagy, whereas the PCD inhibitor Acetyl-Asp-Glu-Val-Asp-aldehyde (Ac-DEVD-CHO) enhanced autophagy gene expression. Autophagy and B. cinerea-induced PCD in berry cells are reciprocally negatively regulated; and the rapamycin and Ac-DEVD-CHO could potentially maintain table grape edible quality.
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Affiliation(s)
- Yizhou Xiang
- College of Biosystems Engineering and Food Science, Fuli Institute of Food Science, Key Laboratory of Agro-Products Postharvest Handling, Ministry of Agriculture and Rural Affairs, Zhejiang University, Hangzhou, China.
| | - Hemao Yuan
- College of Biosystems Engineering and Food Science, Fuli Institute of Food Science, Key Laboratory of Agro-Products Postharvest Handling, Ministry of Agriculture and Rural Affairs, Zhejiang University, Hangzhou, China.
| | - Mengfei Mao
- College of Biosystems Engineering and Food Science, Fuli Institute of Food Science, Key Laboratory of Agro-Products Postharvest Handling, Ministry of Agriculture and Rural Affairs, Zhejiang University, Hangzhou, China.
| | - Qiannan Hu
- College of Biosystems Engineering and Food Science, Fuli Institute of Food Science, Key Laboratory of Agro-Products Postharvest Handling, Ministry of Agriculture and Rural Affairs, Zhejiang University, Hangzhou, China.
| | - Yingying Dong
- College of Biosystems Engineering and Food Science, Fuli Institute of Food Science, Key Laboratory of Agro-Products Postharvest Handling, Ministry of Agriculture and Rural Affairs, Zhejiang University, Hangzhou, China.
| | - Lei Wang
- College of Biosystems Engineering and Food Science, Fuli Institute of Food Science, Key Laboratory of Agro-Products Postharvest Handling, Ministry of Agriculture and Rural Affairs, Zhejiang University, Hangzhou, China.
| | - Bin Wu
- Institute of Agro-products Storage and Processing & Xinjiang Key Laboratory of Processing and Preservation of Agricultural Products, Xinjiang Academy of Agricultural Science, Urumqi 830091, China.
| | - Zisheng Luo
- College of Biosystems Engineering and Food Science, Fuli Institute of Food Science, Key Laboratory of Agro-Products Postharvest Handling, Ministry of Agriculture and Rural Affairs, Zhejiang University, Hangzhou, China; National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang Engineering Laboratory of Food Technology and Equipment, Zhejiang University, Hangzhou, China; Ningbo Research Institute, Zhejiang University, Ningbo, China.
| | - Li Li
- College of Biosystems Engineering and Food Science, Fuli Institute of Food Science, Key Laboratory of Agro-Products Postharvest Handling, Ministry of Agriculture and Rural Affairs, Zhejiang University, Hangzhou, China; National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang Engineering Laboratory of Food Technology and Equipment, Zhejiang University, Hangzhou, China; Ningbo Research Institute, Zhejiang University, Ningbo, China.
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5
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Welch T, Bayon C, Rudd JJ, Kanyuka K, Kettles GJ. Induction of distinct plant cell death programs by secreted proteins from the wheat pathogen Zymoseptoria tritici. Sci Rep 2022; 12:17880. [PMID: 36284131 PMCID: PMC9596407 DOI: 10.1038/s41598-022-22660-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 10/18/2022] [Indexed: 01/20/2023] Open
Abstract
Cell death processes in eukaryotes shape normal development and responses to the environment. For plant-microbe interactions, initiation of host cell death plays an important role in determining disease outcomes. Cell death pathways are frequently initiated following detection of pathogen-derived molecules which can lead to resistance or susceptibility to disease depending on pathogen lifestyle. We previously identified several small secreted proteins (SSPs) from the wheat-infecting fungus Zymoseptoria tritici that induce rapid cell death in Nicotiana benthamiana following Agrobacterium-mediated delivery and expression (agroinfiltration). Here we investigated whether the execution of host cells was mechanistically similar in response to different Z. tritici SSPs. Using RNA sequencing, we found that transient expression of four Z. tritici SSPs led to massive transcriptional reprogramming within 48 h of agroinfiltration. We observed that distinct host gene expression profiles were induced dependent on whether cell death occurs in a cell surface immune receptor-dependent or -independent manner. These gene expression profiles involved differential transcriptional networks mediated by WRKY, NAC and MYB transcription factors. In addition, differential expression of genes belonging to different classes of receptor-like proteins and receptor-like kinases was observed. These data suggest that different Z. tritici SSPs trigger differential transcriptional reprogramming in plant cells.
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Affiliation(s)
- Thomas Welch
- grid.6572.60000 0004 1936 7486Birmingham Institute of Forest Research, University of Birmingham, Edgbaston, Birmingham, B15 2TT UK ,grid.6572.60000 0004 1936 7486School of Biosciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT UK
| | - Carlos Bayon
- grid.418374.d0000 0001 2227 9389Wheat Pathogenomics Team, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ UK
| | - Jason J. Rudd
- grid.418374.d0000 0001 2227 9389Wheat Pathogenomics Team, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ UK
| | - Kostya Kanyuka
- grid.17595.3f0000 0004 0383 6532Cambridge Crop Research, National Institute of Agricultural Botany (NIAB), 93 Lawrence Weaver Road, Cambridge, CB3 0LE UK
| | - Graeme J. Kettles
- grid.6572.60000 0004 1936 7486Birmingham Institute of Forest Research, University of Birmingham, Edgbaston, Birmingham, B15 2TT UK ,grid.6572.60000 0004 1936 7486School of Biosciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT UK
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Li X, An M, Xu C, Jiang L, Yan F, Yang Y, Zhang C, Wu Y. Integrative transcriptome analysis revealed the pathogenic molecular basis of Rhizoctonia solani AG-3 TB at three progressive stages of infection. Front Microbiol 2022; 13:1001327. [PMID: 36304957 PMCID: PMC9593035 DOI: 10.3389/fmicb.2022.1001327] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Accepted: 09/16/2022] [Indexed: 12/04/2022] Open
Abstract
Rhizoctonia solani has a broad host range and results in significant losses in agricultural production. Here, an integrated transcriptomic analysis was performed to reveal the critical genes responsible for the pathogenesis of R. solani AG-3 TB on Nicotiana tabacum at different infection stages. The results showed that various differential expressed genes (DEGs) were enriched in fatty acid metabolism, amino sugar, carbon metabolism, and cellular carbohydrate biosynthetic process at the early (6–12 hpi), middle (24–36 hpi), and late stage (48–72 hpi) of infection. Specifically, several critical genes such as shikimate kinase that were involved in the biosynthesis of an important fungal toxin, phenylacetic acid (PAA) showed markedly increase at 24 hpi. Additionally, the genes expression levels of carbohydrate-active enzymes (CAZymes) and cell wall degrading enzymes (CWDEs) were significantly increased at the late infection stage. Furthermore, we identified 807 potential secreted proteins and 78 small cysteine-rich proteins, which may function as fungal effectors and involved in the pathogenicity. These results provide valuable insights into critical and potential genes as well as the pathways involved in the pathogenesis of R. solani AG-3 TB.
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Affiliation(s)
- Xinchun Li
- Liaoning Key Laboratory of Plant Pathology, College of Plant Protection, Shenyang Agricultural University, Shenyang, China
| | - Mengnan An
- Liaoning Key Laboratory of Plant Pathology, College of Plant Protection, Shenyang Agricultural University, Shenyang, China
| | - Chuantao Xu
- Liaoning Key Laboratory of Plant Pathology, College of Plant Protection, Shenyang Agricultural University, Shenyang, China
- Luzhou Branch of Sichuan Province Tobacco Company, Luzhou, China
| | - Lianqiang Jiang
- Liangshan Branch of Sichuan Province Tobacco Company, Xichang, China
| | - Fangfang Yan
- Panzhihua Branch of Sichuan Province Tobacco Company, Panzhihua, China
| | - Yang Yang
- Yibin Branch of Sichuan Province Tobacco Company, Yibin, China
| | - Chong Zhang
- Liaoning Key Laboratory of Plant Pathology, College of Plant Protection, Shenyang Agricultural University, Shenyang, China
- *Correspondence: Chong Zhang,
| | - Yuanhua Wu
- Liaoning Key Laboratory of Plant Pathology, College of Plant Protection, Shenyang Agricultural University, Shenyang, China
- Yuanhua Wu,
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Roles of Species-Specific Legumains in Pathogenicity of the Pinewood Nematode Bursaphelenchus xylophilus. Int J Mol Sci 2022; 23:ijms231810437. [PMID: 36142347 PMCID: PMC9499627 DOI: 10.3390/ijms231810437] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 08/24/2022] [Accepted: 08/31/2022] [Indexed: 11/16/2022] Open
Abstract
Peptidases are very important to parasites, which have central roles in parasite biology and pathogenesis. In this study, by comparative genome analysis, genome-wide peptidase diversities among plant-parasitic nematodes are estimated. We find that genes encoding cysteine peptidases in family C13 (legumain) are significantly abundant in pine wood nematodes Bursaphelenchus genomes, compared to those in other plant-parasitic nematodes. By phylogenetic analysis, a clade of B. xylophilus-specific legumain is identified. RT-qPCR detection shows that these genes are highly expressed at early stage during the nematode infection process. Utilizing transgene technology, cDNAs of three species-specific legumain were introduced into the Arabidopsis γvpe mutant. Functional complementation assay shows that these B. xylophilus legumains can fully complement the activity of Arabidopsis γVPE to mediate plant cell death triggered by the fungal toxin FB1. Secretory activities of these legumains are experimentally validated. By comparative transcriptome analysis, genes involved in plant cell death mediated by legumains are identified, which enrich in GO terms related to ubiquitin protein transferase activity in category molecular function, and response to stimuli in category biological process. Our results suggest that B. xylophilu-specific legumains have potential as effectors to be involved in nematode-plant interaction and can be related to host cell death.
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Hlihor RM, Roșca M, Hagiu-Zaleschi L, Simion IM, Daraban GM, Stoleru V. Medicinal Plant Growth in Heavy Metals Contaminated Soils: Responses to Metal Stress and Induced Risks to Human Health. TOXICS 2022; 10:toxics10090499. [PMID: 36136464 PMCID: PMC9504071 DOI: 10.3390/toxics10090499] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 08/22/2022] [Accepted: 08/23/2022] [Indexed: 05/31/2023]
Abstract
Accelerating heavy metal pollution is a hot issue due to a continuous growth in consumerism and increased activities in various global industries. Soil contamination with heavy metals has resulted in their incorporation into the human food web via plant components. Accumulation and amplification of heavy metals in human tissues through the consumption of medicinal plants can have hazardous health outcomes. Therefore, in this critical review we aim to bring together published information on this subject, with a special highlight on the knowledge gaps related to heavy metal stress in medicinal plants, their responses, and human health related risks. In this respect, this review outlines the key contamination sources of heavy metals in plants, as well as the absorption, mobilization and translocation of metal ions in plant compartments, while considering their respective mechanisms of detoxification. In addition, this literature review attempts to highlight how stress and defensive strategies operate in plants, pointing out the main stressors, either biotic or abiotic (e.g., heavy metals), and the role of reactive oxygen species (ROS) in stress answers. Finally, in our research, we further aim to capture the risks caused by heavy metals in medicinal plants to human health through the assessment of both a hazard quotient (HQ) and hazard index (HI).
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Affiliation(s)
- Raluca Maria Hlihor
- Department of Horticultural Technologies, Faculty of Horticulture, “Ion Ionescu de la Brad” Iasi University of Life Sciences, 3 Mihail Sadoveanu Alley, 700490 Iasi, Romania
| | - Mihaela Roșca
- Department of Horticultural Technologies, Faculty of Horticulture, “Ion Ionescu de la Brad” Iasi University of Life Sciences, 3 Mihail Sadoveanu Alley, 700490 Iasi, Romania
| | - Laura Hagiu-Zaleschi
- Department of Horticultural Technologies, Faculty of Horticulture, “Ion Ionescu de la Brad” Iasi University of Life Sciences, 3 Mihail Sadoveanu Alley, 700490 Iasi, Romania
| | - Isabela Maria Simion
- Department of Horticultural Technologies, Faculty of Horticulture, “Ion Ionescu de la Brad” Iasi University of Life Sciences, 3 Mihail Sadoveanu Alley, 700490 Iasi, Romania
| | - Gabriel Mihăiță Daraban
- Department of Organic, Biochemical and Food Engineering, “Cristofor Simionescu” Faculty of Chemical Engineering and Environmental Protection, “Gheorghe Asachi” Technical University of Iasi, 73 Prof. D. Mangeron Blvd., 700050 Iasi, Romania
| | - Vasile Stoleru
- Department of Horticultural Technologies, Faculty of Horticulture, “Ion Ionescu de la Brad” Iasi University of Life Sciences, 3 Mihail Sadoveanu Alley, 700490 Iasi, Romania
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9
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Singh NK, Badet T, Abraham L, Croll D. Rapid sequence evolution driven by transposable elements at a virulence locus in a fungal wheat pathogen. BMC Genomics 2021; 22:393. [PMID: 34044766 PMCID: PMC8157644 DOI: 10.1186/s12864-021-07691-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 05/07/2021] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Plant pathogens cause substantial crop losses in agriculture production and threaten food security. Plants evolved the ability to recognize virulence factors and pathogens have repeatedly escaped recognition due rapid evolutionary change at pathogen virulence loci (i.e. effector genes). The presence of transposable elements (TEs) in close physical proximity of effector genes can have important consequences for gene regulation and sequence evolution. Species-wide investigations of effector gene loci remain rare hindering our ability to predict pathogen evolvability. RESULTS Here, we performed genome-wide association studies (GWAS) on a highly polymorphic mapping population of 120 isolates of Zymoseptoria tritici, the most damaging pathogen of wheat in Europe. We identified a major locus underlying significant variation in reproductive success of the pathogen and damage caused on the wheat cultivar Claro. The most strongly associated locus is intergenic and flanked by genes encoding a predicted effector and a serine-type endopeptidase. The center of the locus contained a highly dynamic region consisting of multiple families of TEs. Based on a large global collection of assembled genomes, we show that the virulence locus has undergone substantial recent sequence evolution. Large insertion and deletion events generated length variation between the flanking genes by a factor of seven (5-35 kb). The locus showed also strong signatures of genomic defenses against TEs (i.e. RIP) contributing to the rapid diversification of the locus. CONCLUSIONS In conjunction, our work highlights the power of combining GWAS and population-scale genome analyses to investigate major effect loci in pathogens.
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Affiliation(s)
- Nikhil Kumar Singh
- Laboratory of Evolutionary Genetics, Institute of Biology, University of Neuchâtel, 2000, Neuchâtel, Switzerland
| | - Thomas Badet
- Laboratory of Evolutionary Genetics, Institute of Biology, University of Neuchâtel, 2000, Neuchâtel, Switzerland
| | - Leen Abraham
- Laboratory of Evolutionary Genetics, Institute of Biology, University of Neuchâtel, 2000, Neuchâtel, Switzerland
| | - Daniel Croll
- Laboratory of Evolutionary Genetics, Institute of Biology, University of Neuchâtel, 2000, Neuchâtel, Switzerland.
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10
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Over-Expression of Endogenous SUGARWIN Genes Exalted Tolerance against Colletotrichum Infection in Sugarcane. PLANTS 2021; 10:plants10050869. [PMID: 33925956 PMCID: PMC8146068 DOI: 10.3390/plants10050869] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/20/2021] [Accepted: 04/22/2021] [Indexed: 11/16/2022]
Abstract
Sugarcane being the major contributor of sugar and potential source of biofuel around the globe, occupies significant commercial importance. Red rot is the most devastating disease of sugarcane, severely affecting its quality as well as yield. Here we report the overexpression of SUGARWIN1 and SUGARWIN2 genes in any field crop for the first time. For this purpose, SUGAWIN1 and SUGARWIN2 were cloned downstream of maize ubiquitin (Ubi-1) promoter to construct two independent expression cassettes. The bar gene conferring resistance against phosphinothricin was used as selectable marker. Embryogenic calli of sugarcane were bombarded with both expression cassettes and selected on regeneration medium supplemented with phosphinothricin. The phosphinothricin-resistant shoots were rooted and then, analyzed using molecular tools at the genomic as well as transcriptomic levels. The transcriptomic analysis, using real time qPCR, showed that expression of SUGARWIN1 (SWO) and SUGARWIN2 (SWT) was higher in transgenic plants as compared to untransformed plants. Our results further demonstrated that over expression of these genes under maize ubiquitin (Ubi-1) promoter causes significant restriction in proliferation of red rot causal agent, Colletotrichum falcatum in sugarcane transgenic plants, under in vitro conditions. This report may open up exciting possibilities to extend this technology to other monocots for the development of crops with better ability to withstand fungal pathogens.
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11
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Solanský M, Mikulášek K, Zapletalová M, Petřivalský M, Chiltz A, Zdráhal Z, Leborgne-Castel N, Lochman J. The oligomeric states of elicitins affect the hypersensitive response and resistance in tobacco. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:3219-3234. [PMID: 33475728 DOI: 10.1093/jxb/erab011] [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] [Received: 06/25/2020] [Accepted: 01/19/2021] [Indexed: 06/12/2023]
Abstract
Successful plant defence against microbial pathogens is based on early recognition and fast activation of inducible responses. Key mechanisms include detection of microbe-associated molecular patterns by membrane-localized pattern recognition receptors that induce a basal resistance response. A well-described model of such responses to pathogens involves the interactions between Solanaceae plants and proteinaceous elicitors secreted by oomycetes, called elicitins. It has been hypothesized that the formation of oligomeric structures by elicitins could be involved in their recognition and activation of defensive transduction cascades. In this study, we tested this hypothesis using several approaches, and we observed differences in tobacco plant responses induced by the elicitin β-cryptogein (β-CRY) and its homodimer, β-CRYDIM. We also found that the C-terminal domain of elicitins of other ELI (true-elicitin) clades plays a significant role in stabilization of their oligomeric structure and restraint in the cell wall. In addition, covalently cross-linking β-CRYDIM impaired the formation of signalling complexes, thereby reducing its capacity to elicit the hypersensitive response and resistance in the host plant, with no significant changes in pathogenesis-related protein expression. By revealing the details of the effects of β-CRY dimerization on recognition and defence responses in tobacco, our results shed light on the poorly understood role of elicitins' oligomeric structures in the interactions between oomycetes and plants.
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Affiliation(s)
- Martin Solanský
- Department of Biochemistry, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic
| | - Kamil Mikulášek
- Central European Institute of Technology, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Martina Zapletalová
- Department of Biochemistry, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic
| | - Marek Petřivalský
- Department of Biochemistry, Department of Botany, Faculty of Science, Palacký University, Šlechtitelů 27, 78371 Olomouc, Czech Republic
| | - Annick Chiltz
- Agroécologie, AgroSup Dijon, CNRS, INRAE, Université Bourgogne Franche-Comté, F-21000 Dijon, France
| | - Zbyněk Zdráhal
- Central European Institute of Technology, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Nathalie Leborgne-Castel
- Agroécologie, AgroSup Dijon, CNRS, INRAE, Université Bourgogne Franche-Comté, F-21000 Dijon, France
| | - Jan Lochman
- Department of Biochemistry, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic
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12
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Genome-wide transcriptome reveals mechanisms underlying Rlm1-mediated blackleg resistance on canola. Sci Rep 2021; 11:4407. [PMID: 33623070 PMCID: PMC7902848 DOI: 10.1038/s41598-021-83267-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Accepted: 02/01/2021] [Indexed: 11/08/2022] Open
Abstract
Genetic resistance to blackleg (Leptosphaeria maculans, Lm) of canola (Brassica napus, Bn) has been extensively studied, but the mechanisms underlying the host-pathogen interaction are still not well understood. Here, a comparative transcriptome analysis was performed on a resistant doubled haploid Bn line carrying the resistance gene Rlm1 following inoculation with a virulent (avrLm1) or avirulent (AvrLm1) Lm isolate on cotyledons. A total of 6999 and 3015 differentially expressed genes (DEGs) were identified, respectively, in inoculated local tissues with compatible (susceptible) and incompatible (resistant) interactions. Functional enrichment analysis found several biological processes, including protein targeting to membrane, ribosome and negative regulation of programmed cell death, were over-represented exclusively among up-regulated DEGs in the resistant reaction, whereas significant enrichment of salicylic acid (SA) and jasmonic acid (JA) pathways observed for down-regulated DEGs occurred only in the susceptible reaction. A heat-map analysis showed that both biosynthesis and signaling of SA and JA were induced more significantly in the resistant reaction, implying that a threshold level of SA and JA signaling is required for the activation of Rlm1-mediated resistance. Co-expression network analysis revealed close correlation of a gene module with the resistance, involving DEGs regulating pathogen-associated molecular pattern recognition, JA signaling and transcriptional reprogramming. Substantially fewer DEGs were identified in mock-inoculated (control) cotyledons, relative to those in inoculated local tissues, including those involved in SA pathways potentially contributing to systemic acquired resistance (SAR). Pre-inoculation of cotyledon with either an avirulent or virulent Lm isolate, however, failed to induce SAR on remote tissues of same plant despite elevated SA and PR1 protein. This study provides insights into the molecular mechanism of Rlm1-mediated resistance to blackleg.
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13
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Lukan T, Pompe‐Novak M, Baebler Š, Tušek‐Žnidarič M, Kladnik A, Križnik M, Blejec A, Zagorščak M, Stare K, Dušak B, Coll A, Pollmann S, Morgiewicz K, Hennig J, Gruden K. Precision transcriptomics of viral foci reveals the spatial regulation of immune-signaling genes and identifies RBOHD as an important player in the incompatible interaction between potato virus Y and potato. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 104:645-661. [PMID: 32772469 PMCID: PMC7692943 DOI: 10.1111/tpj.14953] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Accepted: 07/21/2020] [Indexed: 05/18/2023]
Abstract
Whereas the activation of resistance (R) proteins has been intensively studied, the downstream signaling mechanisms leading to the restriction of the pathogen remain mostly unknown. We studied the immunity network response conditioned by the potato Ny-1 gene against potato virus Y. We analyzed the processes in the cell death zone and surrounding tissue on the biochemical and gene expression levels in order to reveal the spatiotemporal regulation of the immune response. We show that the transcriptional response in the cell death zone and surrounding tissue is dependent on salicylic acid (SA). For some genes the spatiotemporal regulation is completely lost in the SA-deficient line, whereas other genes show a different response, indicating multiple connections between hormonal signaling modules. The induction of NADPH oxidase RBOHD expression occurs specifically on the lesion border during the resistance response. In plants with silenced RBOHD, the functionality of the resistance response is perturbed and the spread of the virus is not arrested at the site of infection. RBOHD is required for the spatial accumulation of SA, and conversely RBOHD is under the transcriptional regulation of SA. Using spatially resolved RNA-seq, we also identified spatial regulation of an UDP-glucosyltransferase, another component in feedback activation of SA biosynthesis, thus deciphering a novel aspect of resistance signaling.
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Affiliation(s)
- Tjaša Lukan
- National Institute of BiologyVečna pot 111Ljubljana1000Slovenia
| | | | - Špela Baebler
- National Institute of BiologyVečna pot 111Ljubljana1000Slovenia
| | | | - Aleš Kladnik
- Biotechnical FacultyUniversity of LjubljanaJamnikarjeva 101Ljubljana1000Slovenia
| | - Maja Križnik
- National Institute of BiologyVečna pot 111Ljubljana1000Slovenia
| | - Andrej Blejec
- National Institute of BiologyVečna pot 111Ljubljana1000Slovenia
| | - Maja Zagorščak
- National Institute of BiologyVečna pot 111Ljubljana1000Slovenia
| | - Katja Stare
- National Institute of BiologyVečna pot 111Ljubljana1000Slovenia
| | - Barbara Dušak
- National Institute of BiologyVečna pot 111Ljubljana1000Slovenia
| | - Anna Coll
- National Institute of BiologyVečna pot 111Ljubljana1000Slovenia
| | - Stephan Pollmann
- Centre for Plant Biotechnology and GenomicsCampus de Montegancedo Crta M‐40, Km 38Pozuelo de Alarcón, Madrid28223UPM–INIA Spain
| | - Karolina Morgiewicz
- Institute of Biochemistry and BiophysicsPolish Academy of SciencesPawińskiego 5aWarsaw02‐106Poland
| | - Jacek Hennig
- Institute of Biochemistry and BiophysicsPolish Academy of SciencesPawińskiego 5aWarsaw02‐106Poland
| | - Kristina Gruden
- National Institute of BiologyVečna pot 111Ljubljana1000Slovenia
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14
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Sunisha C, Sowmya HD, Usharani TR, Umesha M, Gopalkrishna HR, Sriram S. Induction of Ced9 mediated anti-apoptosis in commercial banana cultivar Rasthali for stable resistance against Fusarium wilt. 3 Biotech 2020; 10:371. [PMID: 32832331 DOI: 10.1007/s13205-020-02357-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 07/24/2020] [Indexed: 11/30/2022] Open
Abstract
Anti-apoptotic gene Ced-9 enhanced resistance against Fusarium oxysporum f. sp. cubense (Foc) in the susceptible banana cultivar Rasthali by arresting tissue necrosis. The embryogenic cell suspension of banana cultivar Rasthali was stably transformed with Ced-9 gene and transformed lines were regenerated independently. The putative transgenic lines were analyzed with PCR using gene primers and further subjected to Southern blot to estimate copy number. The root-challenge bioassay with Foc showed 17-51% Vascular Discoloration Index in independent transformants compared to untransformed banana cv Rasthali (98% VDI). Four transgenic events showed a higher level of resistance over a period of 6 months. Overcoming tissue necrosis is the most ideal method to avoid Fusarium multiplication and spread in banana. Oxidative stress-induced cell necrosis is prevented by the activation of antiapoptotic pathways by Ced-9 and is proving to be an effective method to control this dreaded disease. This is the first report from India on the generation of transgenic banana cultivar Rasthali expressing antiapoptotic Ced-9 gene for resistance to Fusarium wilt.
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Affiliation(s)
- C Sunisha
- Division of Biotechnology, ICAR-Indian Institute of Horticultural Research, Hessaraghatta, Bangalore, 560 089 India
- Department of Biotechnology and Biochemistry, Centre for Postgraduate Studies, Jain University, Bangalore, India
| | - H D Sowmya
- Division of Biotechnology, ICAR-Indian Institute of Horticultural Research, Hessaraghatta, Bangalore, 560 089 India
| | - T R Usharani
- Division of Biotechnology, ICAR-Indian Institute of Horticultural Research, Hessaraghatta, Bangalore, 560 089 India
| | - M Umesha
- Division of Biotechnology, ICAR-Indian Institute of Horticultural Research, Hessaraghatta, Bangalore, 560 089 India
| | - H R Gopalkrishna
- Division of Biotechnology, ICAR-Indian Institute of Horticultural Research, Hessaraghatta, Bangalore, 560 089 India
| | - S Sriram
- Division of Biotechnology, ICAR-Indian Institute of Horticultural Research, Hessaraghatta, Bangalore, 560 089 India
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15
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Pontes JGDM, Fernandes LS, Dos Santos RV, Tasic L, Fill TP. Virulence Factors in the Phytopathogen-Host Interactions: An Overview. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:7555-7570. [PMID: 32559375 DOI: 10.1021/acs.jafc.0c02389] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Phytopathogens are responsible for great losses in agriculture, once they are able to subvert or elude the host defense mechanisms through virulence factors secretion for their dissemination. Herein, it is reviewed phytotoxins that act as virulence factors and are produced by bacterial phytopathogens (Candidatus Liberibacter spp., Erwinia amylovora, Pseudomonas syringae pvs and Xanthomonas spp.) and fungi (Alternaria alternata, Botrytis cinerea, Cochliobolus spp., Fusarium spp., Magnaporthe spp., and Penicillium spp.), which were selected in accordance to their worldwide importance due to the biochemical and economical aspects. In the current review, it is sought to understand the role of virulence factors in the pathogen-host interactions that result in plant diseases.
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Affiliation(s)
| | - Laura Soler Fernandes
- Laboratório de Biologia Quı́mica Microbiana (LaBioQuiMi), IQ-UNICAMP, Campinas, SP, Brazil
| | | | - Ljubica Tasic
- Laboratório de Quı́mica Biológica (LQB), IQ-UNICAMP, Campinas, SP, Brazil
| | - Taicia Pacheco Fill
- Laboratório de Biologia Quı́mica Microbiana (LaBioQuiMi), IQ-UNICAMP, Campinas, SP, Brazil
- Institute of Chemistry, Universidade Estadual de Campinas (UNICAMP), P.O. Box 6154, 13083970 Campinas, SP, Brazil
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16
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Integrative transcriptome analysis discloses the molecular basis of a heterogeneous fungal phytopathogen complex, Rhizoctonia solani AG-1 subgroups. Sci Rep 2019; 9:19626. [PMID: 31873088 PMCID: PMC6928066 DOI: 10.1038/s41598-019-55734-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 11/26/2019] [Indexed: 02/06/2023] Open
Abstract
Rhizoctonia solani is a fungal species complex that causes necrotrophic crop diseases. It comprises several anastomosis groups, some of which include intra-subgroups, such as AG-1 IA and AG-1 IB, exhibiting varying pathogenicity. Owing to its heterozygous and multinucleate features, genomic analyses of R. solani are still challenging, and understanding of its genetic diversity and genic components is limited. In this study, in order to elucidate the molecular basis of this phytopathogen complex, an integrated transcriptome analysis was undertaken for three subgroups of AG-1, i.e. AG-1 IA, AG-1 IB, and AG-1 IC. Sequence variations suggested substantial evolutionary distances within AG-1. Transcript simple sequence repeats showed comparable characteristics among AG-1, but contained polymorphic sites. Intra-subgroup polymorphisms suggested varying genic heterozygosity within AG-1, suggesting their independent evolutionary trajectory. Sequences of pathogenic factors, phytotoxin biosynthesis pathway enzymes, secreted lignocellulosic enzymes, secreted reactive oxygen species detoxification enzymes, apoplastic/cytoplasmic effector candidates, were conserved among those subgroups. dN/dS ratios of a secretome subset suggested core secreted proteins in AG-1 and distinct evolution of Cys-rich small secreted proteins after differentiation of AG-1 subgroups. Identification of likely pathogenic factors including allergen protein homologues, oxidative phosphorylation and ethylene biosynthesis pathways, and diversification of polysaccharide monooxygenases provides molecular insight into key genomic components that play a role in R. solani pathogenesis.
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17
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Bönnighausen J, Schauer N, Schäfer W, Bormann J. Metabolic profiling of wheat rachis node infection by Fusarium graminearum - decoding deoxynivalenol-dependent susceptibility. THE NEW PHYTOLOGIST 2019; 221:459-469. [PMID: 30084118 DOI: 10.1111/nph.15377] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 07/09/2018] [Indexed: 05/20/2023]
Abstract
Fusarium graminearum is a filamentous ascomycete and the causal agent of Fusarium head blight on wheat that threatens food and feed production worldwide as infection reduces crop yield both quantitatively by interfering with kernel development and qualitatively by poisoning any remaining kernels with mycotoxins. In wheat, F. graminearum infects spikelets and colonizes the entire head by growing through the rachis node at the bottom of each spikelet. Without the mycotoxin deoxynivalenol (DON), the pathogen cannot penetrate the rachis node and wheat is able to resist colonization. Using a global metabolite profiling approach we compared the metabolic profile of rachis nodes inoculated with either water, the Fusarium graminearum wild-type or the DON-deficient ∆tri5 mutant. Extensive metabolic rearrangements mainly affect metabolites for general stress perception and signaling, reactive oxygen species (ROS) metabolism, cell wall composition, the tri-carbonic acid (TCA) cycle and γ-aminobutyric acid (GABA) shunt as well as sugar alcohols, amino acids, and storage carbohydrates. The results revealed specific, DON-related susceptibility factors. Wild-type infection resulted in an oxidative burst and the induction of plant programmed cell death, while spread of the DON-deficient mutant was blocked in a jasmonate (JA)-related defense reaction in concert with other factors. Hence, the ∆tri5 mutant is prone to defense reactions that are, in the case of a wild-type infection, not initiated.
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Affiliation(s)
- Jakob Bönnighausen
- Department of Molecular Phytopathology, Institute of Plant Science and Microbiology (IPM), University of Hamburg, Ohnhorststr. 18, D-22609, Hamburg, Germany
| | - Nicolas Schauer
- Metabolomic Discoveries GmbH, Am Mühlenberg 11, D-14476, Potsdam, Germany
| | - Wilhelm Schäfer
- Department of Molecular Phytopathology, Institute of Plant Science and Microbiology (IPM), University of Hamburg, Ohnhorststr. 18, D-22609, Hamburg, Germany
| | - Jörg Bormann
- Department of Molecular Phytopathology, Institute of Plant Science and Microbiology (IPM), University of Hamburg, Ohnhorststr. 18, D-22609, Hamburg, Germany
- Department for Cell Biology, University of Bremen, Leobener Str. NW2, 28359, Bremen, Germany
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18
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Lincoln JE, Sanchez JP, Zumstein K, Gilchrist DG. Plant and animal PR1 family members inhibit programmed cell death and suppress bacterial pathogens in plant tissues. MOLECULAR PLANT PATHOLOGY 2018; 19:2111-2123. [PMID: 29603552 PMCID: PMC6638019 DOI: 10.1111/mpp.12685] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 03/14/2018] [Accepted: 03/25/2018] [Indexed: 05/20/2023]
Abstract
A role for programmed cell death (PCD) has been established as the basis for plant-microbe interactions. A functional plant-based cDNA library screen identified possible anti-PCD genes, including one member of the PR1 family, designated P14a, from tomato. Members of the PR1 family have been subject to extensive research in view of their possible role in resistance against pathogens. The PR1 family is represented in every plant species studied to date and homologues have been found in animals, fungi and insects. However, the biological function of the PR1 protein from plants has remained elusive in spite of extensive research regarding a role in the response of plants to disease. Constitutive expression of P14a in transgenic tomato roots protected the roots against PCD triggered by Fumonisin B1, as did the human orthologue GLIPR1, indicating a kingdom crossing function for PR1. Tobacco plants transformed with a P14a-GFP fusion construct and inoculated with Pseudomonas syringae pv. tabaci revealed that the mRNA was abundant throughout the leaves, but the fusion protein was restricted to the lesion margins, where cell death and bacterial spread were arrested. Vitus vinifera grapes expressing the PR1 homologue P14a as a transgene were protected against the cell death symptoms of Pierce's disease. A pull-down assay identified putative PR1-interacting proteins, including members of the Rac1 immune complex, known to function in innate immunity in rice and animal systems. The findings herein are consistent with a role of PR1 in the suppression of cell death-dependent disease symptoms and a possible mode of action.
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Affiliation(s)
- James E. Lincoln
- Department of Plant PathologyUniversity of CaliforniaDavisCA 95616USA
| | - Juan P. Sanchez
- Department of Plant PathologyUniversity of CaliforniaDavisCA 95616USA
- Present address:
Monsanto CompanyWoodlandCA 95695USA
| | - Kristina Zumstein
- Department of Plant PathologyUniversity of CaliforniaDavisCA 95616USA
- Present address:
Department of Plant ScienceUniversity of CaliforniaDavisCA 95616USA
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19
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Shalaby S, Larkov O, Lamdan NL, Goldshmidt-Tran O, Horwitz BA. Plant phenolic acids induce programmed cell death of a fungal pathogen: MAPK signaling and survival of Cochliobolus heterostrophus. Environ Microbiol 2016; 18:4188-4199. [PMID: 27631532 DOI: 10.1111/1462-2920.13528] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 09/09/2016] [Indexed: 11/29/2022]
Abstract
Plant aromatic compounds provide signals and a nutrient source to pathogens, and also act as stressors. Structure-activity relationships suggest two pathways sensing these compounds in the maize pathogen Cochliobolus heterostrophus, one triggering a stress response, and one inducing enzymes for their degradation. Focusing on the stress pathway, we found that ferulic acid causes rapid appearance of TUNEL-positive nuclei, dispersion of histone H1:GFP, hyphal shrinkage, and eventually membrane damage. These hallmarks of programmed cell death (PCD) were not seen upon exposure to caffeic acid, a very similar compound. Exposure to ferulic acid dephosphorylated two MAP kinases: Hog1 (stress activated) and Chk1 (pathogenicity related), while increasing phosphorylation of Mps1 (cell integrity related). Mutants lacking Hog1 or Chk1 are hypersensitive to ferulic acid while Mps1 mutants are not. These results implicate three MAPK pathways in the stress response. Ferulic acid and the antifungal fludioxonil have opposite additive effects on survival and on dephosphorylation of Hog1, which is thus implicated in survival. The results may explain why some fungal pathogens of plants undergo cell death early in host invasion, when phenolics are released from plant tissue.
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Affiliation(s)
- Samer Shalaby
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa, 3200000, Israel
| | - Olga Larkov
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa, 3200000, Israel
| | - Netta-Li Lamdan
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa, 3200000, Israel
| | - Orit Goldshmidt-Tran
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa, 3200000, Israel
| | - Benjamin A Horwitz
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa, 3200000, Israel
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20
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Moshe A, Gorovits R, Liu Y, Czosnek H. Tomato plant cell death induced by inhibition of HSP90 is alleviated by Tomato yellow leaf curl virus infection. MOLECULAR PLANT PATHOLOGY 2016; 17:247-60. [PMID: 25962748 PMCID: PMC6638530 DOI: 10.1111/mpp.12275] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
To ensure a successful long-term infection cycle, begomoviruses must restrain their destructive effect on host cells and prevent drastic plant responses, at least in the early stages of infection. The monopartite begomovirus Tomato yellow leaf curl virus (TYLCV) does not induce a hypersensitive response and cell death on whitefly-mediated infection of virus-susceptible tomato plants until diseased tomatoes become senescent. The way in which begomoviruses evade plant defences and interfere with cell death pathways is still poorly understood. We show that the chaperone HSP90 (heat shock protein 90) and its co-chaperone SGT1 (suppressor of the G2 allele of Skp1) are involved in the establishment of TYLCV infection. Inactivation of HSP90, as well as silencing of the Hsp90 and Sgt1 genes, leads to the accumulation of damaged ubiquitinated proteins and to a cell death phenotype. These effects are relieved under TYLCV infection. HSP90-dependent inactivation of 26S proteasome degradation and the transcriptional activation of the heat shock transcription factors HsfA2 and HsfB1 and of the downstream genes Hsp17 and Apx1/2 are suppressed in TYLCV-infected tomatoes. Following suppression of the plant stress response, TYLCV can replicate and accumulate in a permissive environment.
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Affiliation(s)
- Adi Moshe
- Institute of Plant Sciences and Genetics in Agriculture, Robert H. Smith Faculty of Agriculture, Food and Environment, Hebrew University of Jerusalem, Rehovot, 76100, Israel
| | - Rena Gorovits
- Institute of Plant Sciences and Genetics in Agriculture, Robert H. Smith Faculty of Agriculture, Food and Environment, Hebrew University of Jerusalem, Rehovot, 76100, Israel
| | - Yule Liu
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Henryk Czosnek
- Institute of Plant Sciences and Genetics in Agriculture, Robert H. Smith Faculty of Agriculture, Food and Environment, Hebrew University of Jerusalem, Rehovot, 76100, Israel
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21
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Mbengue M, Navaud O, Peyraud R, Barascud M, Badet T, Vincent R, Barbacci A, Raffaele S. Emerging Trends in Molecular Interactions between Plants and the Broad Host Range Fungal Pathogens Botrytis cinerea and Sclerotinia sclerotiorum. FRONTIERS IN PLANT SCIENCE 2016; 7:422. [PMID: 27066056 PMCID: PMC4814483 DOI: 10.3389/fpls.2016.00422] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 03/18/2016] [Indexed: 05/08/2023]
Abstract
Fungal plant pathogens are major threats to food security worldwide. Sclerotinia sclerotiorum and Botrytis cinerea are closely related Ascomycete plant pathogens causing mold diseases on hundreds of plant species. There is no genetic source of complete plant resistance to these broad host range pathogens known to date. Instead, natural plant populations show a continuum of resistance levels controlled by multiple genes, a phenotype designated as quantitative disease resistance. Little is known about the molecular mechanisms controlling the interaction between plants and S. sclerotiorum and B. cinerea but significant advances were made on this topic in the last years. This minireview highlights a selection of nine themes that emerged in recent research reports on the molecular bases of plant-S. sclerotiorum and plant-B. cinerea interactions. On the fungal side, this includes progress on understanding the role of oxalic acid, on the study of fungal small secreted proteins. Next, we discuss the exchanges of small RNA between organisms and the control of cell death in plant and fungi during pathogenic interactions. Finally on the plant side, we highlight defense priming by mechanical signals, the characterization of plant Receptor-like proteins and the hormone abscisic acid in the response to B. cinerea and S. sclerotiorum, the role of plant general transcription machinery and plant small bioactive peptides. These represent nine trends we selected as remarkable in our understanding of fungal molecules causing disease and plant mechanisms associated with disease resistance to two devastating broad host range fungi.
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Wang Y, Cordewener JHG, America AHP, Shan W, Bouwmeester K, Govers F. Arabidopsis Lectin Receptor Kinases LecRK-IX.1 and LecRK-IX.2 Are Functional Analogs in Regulating Phytophthora Resistance and Plant Cell Death. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2015; 28:1032-1048. [PMID: 26011556 DOI: 10.1094/mpmi-02-15-0025-r] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
L-type lectin receptor kinases (LecRK) are potential immune receptors. Here, we characterized two closely-related Arabidopsis LecRK, LecRK-IX.1 and LecRK-IX.2, of which T-DNA insertion mutants showed compromised resistance to Phytophthora brassicae and Phytophthora capsici, with double mutants showing additive susceptibility. Overexpression of LecRK-IX.1 or LecRK-IX.2 in Arabidopsis and transient expression in Nicotiana benthamiana increased Phytophthora resistance but also induced cell death. Phytophthora resistance required both the lectin domain and kinase activity, but for cell death, the lectin domain was not needed. Silencing of the two closely related mitogen-activated protein kinase genes NbSIPK and NbNTF4 in N. benthamiana completely abolished LecRK-IX.1-induced cell death but not Phytophthora resistance. Liquid chromatography-mass spectrometry analysis of protein complexes coimmunoprecipitated in planta with LecRK-IX.1 or LecRK-IX.2 as bait, resulted in the identification of the N. benthamiana ABC transporter NbPDR1 as a potential interactor of both LecRK. The closest homolog of NbPDR1 in Arabidopsis is ABCG40, and coimmunoprecipitation experiments showed that ABCG40 associates with LecRK-IX.1 and LecRK-IX.2 in planta. Similar to the LecRK mutants, ABCG40 mutants showed compromised Phytophthora resistance. This study shows that LecRK-IX.1 and LecRK-IX.2 are Phytophthora resistance components that function independent of each other and independent of the cell-death phenotype. They both interact with the same ABC transporter, suggesting that they exploit similar signal transduction pathways.
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Affiliation(s)
- Yan Wang
- 1 Laboratory of Phytopathology, Plant Sciences Group, Wageningen University, Wageningen, The Netherlands
| | | | | | - Weixing Shan
- 3 State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, P. R. China
| | - Klaas Bouwmeester
- 1 Laboratory of Phytopathology, Plant Sciences Group, Wageningen University, Wageningen, The Netherlands
- 4 Plant-Microbe Interactions, Department of Biology, Faculty of Science, Utrecht University, Utrecht, The Netherlands
| | - Francine Govers
- 1 Laboratory of Phytopathology, Plant Sciences Group, Wageningen University, Wageningen, The Netherlands
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Lee WS, Devonshire BJ, Hammond-Kosack KE, Rudd JJ, Kanyuka K. Deregulation of Plant Cell Death Through Disruption of Chloroplast Functionality Affects Asexual Sporulation of Zymoseptoria tritici on Wheat. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2015; 28:590-604. [PMID: 25496594 DOI: 10.1094/mpmi-10-14-0346-r] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Chloroplasts have a critical role in plant defense as sites for the biosynthesis of the signaling compounds salicylic acid (SA), jasmonic acid (JA), and nitric oxide (NO) and as major sites of reactive oxygen species production. Chloroplasts, therefore, regarded as important players in the induction and regulation of programmed cell death (PCD) in response to abiotic stresses and pathogen attack. The predominantly foliar pathogen of wheat Zymoseptoria tritici is proposed to exploit the plant PCD, which is associated with the transition in the fungus to the necrotrophic phase of infection. In this study virus-induced gene silencing was used to silence two key genes in carotenoid and chlorophyll biosynthesis, phytoene desaturase (PDS) and Mg-chelatase H subunit (ChlH). The chlorophyll-deficient, PDS- and ChlH-silenced leaves of susceptible plants underwent more rapid pathogen-induced PCD but were significantly less able to support the subsequent asexual sporulation of Z. tritici. Conversely, major gene (Stb6)-mediated resistance to Z. tritici was partially compromised in PDS- and ChlH-silenced leaves. Chlorophyll-deficient wheat ears also displayed increased Z. tritici disease lesion formation accompanied by increased asexual sporulation. These data highlight the importance of chloroplast functionality and its interaction with regulated plant cell death in mediating different genotype and tissue-specific interactions between Z. tritici and wheat.
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Affiliation(s)
- Wing-Sham Lee
- 1Wheat Pathogenomics Team, Plant Biology and Crop Science Department, Rothamsted Research, Harpenden, AL5 2JQ, U.K
| | - B Jean Devonshire
- 2Bioimaging, Plant Biology and Crop Science Department, Rothamsted Research, Harpenden, AL5 2JQ, U.K
| | - Kim E Hammond-Kosack
- 1Wheat Pathogenomics Team, Plant Biology and Crop Science Department, Rothamsted Research, Harpenden, AL5 2JQ, U.K
| | - Jason J Rudd
- 1Wheat Pathogenomics Team, Plant Biology and Crop Science Department, Rothamsted Research, Harpenden, AL5 2JQ, U.K
| | - Kostya Kanyuka
- 1Wheat Pathogenomics Team, Plant Biology and Crop Science Department, Rothamsted Research, Harpenden, AL5 2JQ, U.K
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24
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Lehmann S, Serrano M, L'Haridon F, Tjamos SE, Metraux JP. Reactive oxygen species and plant resistance to fungal pathogens. PHYTOCHEMISTRY 2015; 112:54-62. [PMID: 25264341 DOI: 10.1016/j.phytochem.2014.08.027] [Citation(s) in RCA: 163] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Revised: 08/18/2014] [Accepted: 08/28/2014] [Indexed: 05/18/2023]
Abstract
Reactive oxygen species (ROS) have been studied for their role in plant development as well as in plant immunity. ROS were consistently observed to accumulate in the plant after the perception of pathogens and microbes and over the years, ROS were postulated to be an integral part of the defence response of the plant. In this article we will focus on recent findings about ROS involved in the interaction of plants with pathogenic fungi. We will describe the ways to detect ROS, their modes of action and their importance in relation to resistance to fungal pathogens. In addition we include some results from works focussing on the fungal interactor and from studies investigating roots during pathogen attack.
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Affiliation(s)
- Silke Lehmann
- Department of Biology, University of Fribourg, 10 chemin du Musée, CH-1700 Fribourg, Switzerland.
| | - Mario Serrano
- Department of Biology, University of Fribourg, 10 chemin du Musée, CH-1700 Fribourg, Switzerland.
| | - Floriane L'Haridon
- Department of Biology, University of Fribourg, 10 chemin du Musée, CH-1700 Fribourg, Switzerland.
| | - Sotirios E Tjamos
- Laboratory of Plant Pathology, Department of Crop Science, Agricultural University of Athens, 75 Iera Odos, 118 55 Athens, Greece.
| | - Jean-Pierre Metraux
- Department of Biology, University of Fribourg, 10 chemin du Musée, CH-1700 Fribourg, Switzerland.
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25
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Cook DE, Mesarich CH, Thomma BPHJ. Understanding plant immunity as a surveillance system to detect invasion. ANNUAL REVIEW OF PHYTOPATHOLOGY 2015; 53:541-63. [PMID: 26047564 DOI: 10.1146/annurev-phyto-080614-120114] [Citation(s) in RCA: 326] [Impact Index Per Article: 32.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Various conceptual models to describe the plant immune system have been presented. The most recent paradigm to gain wide acceptance in the field is often referred to as the zigzag model, which reconciles the previously formulated gene-for-gene hypothesis with the recognition of general elicitors in a single model. This review focuses on the limitations of the current paradigm of molecular plant-microbe interactions and how it too narrowly defines the plant immune system. As such, we discuss an alternative view of plant innate immunity as a system that evolves to detect invasion. This view accommodates the range from mutualistic to parasitic symbioses that plants form with diverse organisms, as well as the spectrum of ligands that the plant immune system perceives. Finally, how this view can contribute to the current practice of resistance breeding is discussed.
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Affiliation(s)
- David E Cook
- Laboratory of Phytopathology, Wageningen University, 6708 PB Wageningen, The Netherlands; ,
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26
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Pritchard L, Birch PRJ. The zigzag model of plant-microbe interactions: is it time to move on? MOLECULAR PLANT PATHOLOGY 2014; 15:865-70. [PMID: 25382065 PMCID: PMC6638871 DOI: 10.1111/mpp.12210] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Affiliation(s)
- Leighton Pritchard
- Information and Computational Sciences, University of Dundee, Errol Rd, Invergowrie, Dundee, DD2 5DA, UK; Dundee Effector Consortium, University of Dundee, Errol Rd, Invergowrie, Dundee, DD2 5DA, UK; Centre for Human and Animal Pathogens in the Environment, University of Dundee, Errol Rd, Invergowrie, Dundee, DD2 5DA, UK
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27
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Ghag SB, Shekhawat UKS, Ganapathi TR. Native cell-death genes as candidates for developing wilt resistance in transgenic banana plants. AOB PLANTS 2014; 6:plu037. [PMID: 24996429 PMCID: PMC4122335 DOI: 10.1093/aobpla/plu037] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Accepted: 06/24/2014] [Indexed: 05/19/2023]
Abstract
In order to feed an ever-increasing world population, there is an urgent need to improve the production of staple food and fruit crops. The productivity of important food and fruit crops is constrained by numerous biotic and abiotic factors. The cultivation of banana, which is an important fruit crop, is severely threatened by Fusarium wilt disease caused by infestation by an ascomycetes fungus Fusarium oxysporum f. sp. cubense (Foc). Since there are no established edible cultivars of banana resistant to all the pathogenic races of Foc, genetic engineering is the only option for the generation of resistant cultivars. Since Foc is a hemibiotrophic fungus, investigations into the roles played by different cell-death-related genes in the progression of Foc infection on host banana plants are important. Towards this goal, three such genes namely MusaDAD1, MusaBAG1 and MusaBI1 were identified in banana. The study of their expression pattern in banana cells in response to Foc inoculation (using Foc cultures or fungal toxins like fusaric acid and beauvericin) indicated that they were indeed differentially regulated by fungal inoculation. Among the three genes studied, MusaBAG1 showed the highest up-regulation upon Foc inoculation. Further, in order to characterize these genes in the context of Foc infection in banana, we generated transgenic banana plants constitutively overexpressing the three genes that were later subjected to Foc bioassays in a contained greenhouse. Among the three groups of transgenics tested, transformed banana plants overexpressing MusaBAG1 demonstrated the best resistance towards Foc infection. Further, these plants also showed the highest relative overexpression of the transgene (MusaBAG1) among the three groups of transformed plants generated. Our study showed for the first time that native genes like MusaBAG1 can be used to develop transgenic banana plants with efficient resistance towards pathogens like Foc.
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Affiliation(s)
- Siddhesh B Ghag
- Plant Cell Culture Technology Section, Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India
| | - Upendra K Singh Shekhawat
- Plant Cell Culture Technology Section, Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India
| | - Thumballi R Ganapathi
- Plant Cell Culture Technology Section, Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India
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