1
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Sheng H, Ai C, Yang C, Zhu C, Meng Z, Wu F, Wang X, Dou D, Morris PF, Zhang X. A conserved oomycete effector RxLR23 triggers plant defense responses by targeting ERD15La to release NbNAC68. Nat Commun 2024; 15:6336. [PMID: 39068146 PMCID: PMC11283518 DOI: 10.1038/s41467-024-50782-3] [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: 05/20/2023] [Accepted: 07/19/2024] [Indexed: 07/30/2024] Open
Abstract
Oomycete pathogens deliver many effectors to enhance virulence or suppress plant immunity. Plant immune networks are interconnected, in which a few effectors can trigger a strong defense response when recognized by immunity-related proteins. How effectors activate plant defense response remains poorly understood. Here we report Phytophthora capsici effector RxLR23KM can induce plant cell death and plant immunity. RxLR23KM specifically binds to ERD15La, a regulator of abscisic acid and salicylic acid pathway, and the binding intensity depends on the amino acid residues (K93 and M320). NbNAC68, a downstream protein of ERD15La, can stimulate plant immunity that is compromised after binding with ERD15La. Silencing of NbNAC68 substantially prevents the activation of plant defense response. RxLR23KM binds to ERD15La, releasing NbNAC68 to activate plant immunity. These findings highlight a strategy of plant defense response that ERD15La as a central regulator coordinates RxLR23KM to regulate NbNAC68-triggered plant immunity.
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Affiliation(s)
- Hui Sheng
- Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, College of Plant Protection, Shandong Agricultural University, Tai'an, 271018, China
| | - Congcong Ai
- Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, College of Plant Protection, Shandong Agricultural University, Tai'an, 271018, China
| | - Cancan Yang
- Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, College of Plant Protection, Shandong Agricultural University, Tai'an, 271018, China
| | - Chunyuan Zhu
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, 271018, China
| | - Zhe Meng
- College of Life Sciences, Shandong Normal University, Ji'nan, 250014, China
| | - Fengzhi Wu
- Department of Horticulture, Northeast Agricultural University, Harbin, 150030, China
| | - Xiaodan Wang
- College of Plant Protection, China Agricultural University, 100083, Beijing, China
| | - Daolong Dou
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Paul F Morris
- Department of Biological Sciences, Bowling Green State University, Bowling Green, OH, 43043, USA
| | - Xiuguo Zhang
- Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, College of Plant Protection, Shandong Agricultural University, Tai'an, 271018, China.
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2
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Wang Z, Zhong S, Zhang S, Zhang B, Zheng Y, Sun Y, Zhang Q, Liu X. A novel and ubiquitous miRNA-involved regulatory module ensures precise phosphorylation of RNA polymerase II and proper transcription. PLoS Pathog 2024; 20:e1012138. [PMID: 38640110 PMCID: PMC11062530 DOI: 10.1371/journal.ppat.1012138] [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: 10/03/2023] [Revised: 05/01/2024] [Accepted: 03/20/2024] [Indexed: 04/21/2024] Open
Abstract
Proper transcription orchestrated by RNA polymerase II (RNPII) is crucial for cellular development, which is rely on the phosphorylation state of RNPII's carboxyl-terminal domain (CTD). Sporangia, developed from mycelia, are essential for the destructive oomycetes Phytophthora, remarkable transcriptional changes are observed during the morphological transition. However, how these changes are rapidly triggered and their relationship with the versatile RNPII-CTD phosphorylation remain enigmatic. Herein, we found that Phytophthora capsici undergone an elevation of Ser5-phosphorylation in its uncanonical heptapeptide repeats of RNPII-CTD during sporangia development, which subsequently changed the chromosomal occupation of RNPII and primarily activated transcription of certain genes. A cyclin-dependent kinase, PcCDK7, was highly induced and phosphorylated RNPII-CTD during this morphological transition. Mechanistically, a novel DCL1-dependent microRNA, pcamiR1, was found to be a feedback modulator for the precise phosphorylation of RNPII-CTD by complexing with PcAGO1 and regulating the accumulation of PcCDK7. Moreover, this study revealed that the pcamiR1-CDK7-RNPII regulatory module is evolutionarily conserved and the impairment of the balance between pcamiR1 and PcCDK7 could efficiently reduce growth and virulence of P. capsici. Collectively, this study uncovers a novel and evolutionary conserved mechanism of transcription regulation which could facilitate correct development and identifies pcamiR1 as a promising target for disease control.
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Affiliation(s)
- Zhiwen Wang
- China Agricultural University, Beijing, China
- Sanya Institute of China Agricultural University, Sanya, China
| | - Shan Zhong
- China Agricultural University, Beijing, China
| | | | - Borui Zhang
- China Agricultural University, Beijing, China
| | - Yang Zheng
- China Agricultural University, Beijing, China
| | - Ye Sun
- China Agricultural University, Beijing, China
| | | | - Xili Liu
- China Agricultural University, Beijing, China
- State Key Laboratory or Crop Stress Resistance and High-Efficiency Production, Northwest A&F University, Yangling, China
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3
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Wang T, Wang X, Zhu X, He Q, Guo L. A proper PiCAT2 level is critical for sporulation, sporangium function, and pathogenicity of Phytophthora infestans. MOLECULAR PLANT PATHOLOGY 2020; 21:460-474. [PMID: 31997544 PMCID: PMC7060140 DOI: 10.1111/mpp.12907] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 12/12/2019] [Accepted: 12/13/2019] [Indexed: 05/04/2023]
Abstract
Catalase is present in prokaryotic and eukaryotic organisms and is important for the protective effects of the antioxidant system against free radicals. Many studies have confirmed that catalase is required for the growth, development, and pathogenesis of bacteria, plants, animals, and fungi. However, there has been relatively little research on the catalases in oomycetes, which form an important group of fungus-like eukaryotes that produce zoosporangia. In this study, we detected two Phytophthora infestans genes encoding catalases, but only PiCAT2 exhibited catalase activity in the sporulation stage and was highly produced during asexual reproduction and in the late infection stage. Compared with the wild-type strain, the PiCAT2-silenced P. infestans transformants were more sensitive to abiotic stress, were less pathogenic, and had a lower colony expansion rate and lower PiMPK7, PiVPS1, and PiGPG1 expression levels. In contrast, the PiCAT2-overexpressed transformants were slightly less sensitive to abiotic stress. Interestingly, increasing and decreasing PiCAT2 expression from the normal level inhibited sporulation, germination, and infectivity, and down-regulated PiCdc14 expression, but up-regulated PiSDA1 expression. These results suggest that PiCAT2 is required for P. infestans mycelial growth, asexual reproduction, abiotic stress tolerance, and pathogenicity. However, a proper PiCAT2 level is critical for the formation and normal function of sporangia. Furthermore, PiCAT2 affects P. infestans sporangial formation and function, pathogenicity, and abiotic stress tolerance by regulating the expression of cell cycle-related genes (PiCdc14 and PiSDA1) and MAPK pathway genes. Our findings provide new insights into catalase functions in eukaryotic pathogens.
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Affiliation(s)
- Tu‐Hong Wang
- College of Plant Protection and Key Lab of Pest Monitoring and Green ManagementMOAChina Agricultural UniversityBeijingChina
| | - Xiao‐Wen Wang
- College of Plant Protection and Key Lab of Pest Monitoring and Green ManagementMOAChina Agricultural UniversityBeijingChina
| | - Xiao‐Qiong Zhu
- College of Plant Protection and Key Lab of Pest Monitoring and Green ManagementMOAChina Agricultural UniversityBeijingChina
| | - Qun He
- State Key Laboratory of Agrobiotechnology and MOA Key Laboratory of Soil MicrobiologyCollege of Biological SciencesChina Agricultural UniversityBeijingChina
| | - Li‐Yun Guo
- College of Plant Protection and Key Lab of Pest Monitoring and Green ManagementMOAChina Agricultural UniversityBeijingChina
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4
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Ma Y, Yu H, Liu W, Qin Y, Xing R, Li P. Integrated proteomics and metabolomics analysis reveals the antifungal mechanism of the C-coordinated O-carboxymethyl chitosan Cu(II) complex. Int J Biol Macromol 2019; 155:1491-1509. [PMID: 31751736 DOI: 10.1016/j.ijbiomac.2019.11.127] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2019] [Revised: 11/06/2019] [Accepted: 11/14/2019] [Indexed: 12/31/2022]
Abstract
With wide application in agriculture, copper fungicides have undergone three stages of development: inorganic copper, synthetic organic copper, and natural organic copper. Using chitin/chitosan (CS) as a substrate, the natural organic copper fungicide C-coordinated O-carboxymethyl chitosan Cu(II) complex (O-CSLn-Cu) was developed in the laboratory. Taking Phytophthora capsici Leonian as an example, we explored the antifungal mechanism of O-CSLn-Cu by combining tandem mass tag (TMT)-based proteomics with non-targeted liquid chromatography-mass spectrometry (LC-MS)-based metabolomics. A total of 1172 differentially expressed proteins were identified by proteomics analysis. According to the metabolomics analysis, 93 differentially metabolites were identified. Acetyl-CoA-related and membrane localized proteins showed significant differences in the proteomics analysis. Most of the differential expressed metabolites were distributed in the cytoplasm, followed by mitochondria. The integrated analysis revealed that O-CSLn-Cu could induce the "Warburg effect", with increased glycolysis in the cytoplasm and decreased metabolism in the mitochondria. Therefore, P. capsici Leonian had to compensate for ATP loss in the TCA cycle by increasing the glycolysis rate. However, this metabolic shift could not prevent the death of P. capsici Leonian. To verify this hypothesis, a series of biological experiments, such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), and enzyme activity measurements were carried out. The results suggest that O-CSLn-Cu causes mitochondrial injury, which consequently leads to excessive ROS levels and insufficient ATP levels, thereby killing P. capsici Leonian.
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Affiliation(s)
- Yuzhen Ma
- Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Huahua Yu
- Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China.
| | - Weixiang Liu
- Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China
| | - Yukun Qin
- Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China
| | - Ronge Xing
- Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China
| | - Pengcheng Li
- Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China.
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5
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Abstract
Multinucleate fungi and oomycetes are phylogenetically distant but structurally similar. To address whether they share similar nuclear dynamics, we carried out time-lapse imaging of fluorescently labeled Phytophthora palmivora nuclei. Nuclei underwent coordinated bidirectional movements during plant infection. Within hyphal networks growing in planta or in axenic culture, nuclei either are dragged passively with the cytoplasm or actively become rerouted toward nucleus-depleted hyphal sections and often display a very stretched shape. Benomyl-induced depolymerization of microtubules reduced active movements and the occurrence of stretched nuclei. A centrosome protein localized at the leading end of stretched nuclei, suggesting that, as in fungi, astral microtubule-guided movements contribute to nuclear distribution within oomycete hyphae. The remarkable hydrodynamic shape adaptations of Phytophthora nuclei contrast with those in fungi and likely enable them to migrate over longer distances. Therefore, our work summarizes mechanisms which enable a near-equal nuclear distribution in an oomycete. We provide a basis for computational modeling of hydrodynamic nuclear deformation within branched tubular networks.IMPORTANCE Despite their fungal morphology, oomycetes constitute a distinct group of protists related to brown algae and diatoms. Many oomycetes are pathogens and cause diseases of plants, insects, mammals, and humans. Extensive efforts have been made to understand the molecular basis of oomycete infection, but durable protection against these pathogens is yet to be achieved. We use a plant-pathogenic oomycete to decipher a key physiological aspect of oomycete growth and infection. We show that oomycete nuclei travel actively and over long distances within hyphae and during infection. Such movements require microtubules anchored on the centrosome. Nuclei hydrodynamically adapt their shape to travel in or against the flow. In contrast, fungi lack a centrosome and have much less flexible nuclei. Our findings provide a basis for modeling of flexible nuclear shapes in branched hyphal networks and may help in finding hard-to-evade targets to develop specific antioomycete strategies and achieve durable crop disease protection.
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6
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Cheng W, Lin M, Qiu M, Kong L, Xu Y, Li Y, Wang Y, Ye W, Dong S, He S, Wang Y. Chitin synthase is involved in vegetative growth, asexual reproduction and pathogenesis of Phytophthora capsici and Phytophthora sojae. Environ Microbiol 2019; 21:4537-4547. [PMID: 31314944 DOI: 10.1111/1462-2920.14744] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Revised: 07/13/2019] [Accepted: 07/13/2019] [Indexed: 11/29/2022]
Abstract
Chitin is a structural and functional component of the fungal cell wall and also serves as a pathogen-associated molecular pattern (PAMP) that triggers the innate immune responses of host plants. However, no or very little chitin is found in the fungus-like oomycetes. In Phytophthora spp., the presence of chitin has not been demonstrated so far, although putative chitin synthase (CHS) genes, which encode the enzymes that synthesize chitin, are present in their genomes. Here, we revealed that chitin is present in the zoospores and released sporangia of Phytophthora, and this is most consistent with the transcriptional pattern of PcCHS in Phytophthora capsici and PsCHS1 in Phytophthora sojae. Disruption of the CHS genes indicated that PcCHS and PsCHS1, but not PsCHS2 (which exhibited very weak transcription), have similar functions involved in mycelial growth, sporangial production, zoospore release and the pathogenesis of P. capsici and P. sojae. We also suggest that chitin in the zoospores of P. capsici can act as a PAMP that is recognized by the chitin receptors AtLYK5 or AtCERK1 of Arabidopsis. These results provide new insights into the biological significance of chitin and CHSs in Phytophthora and help with the identification of potential targets for disease control.
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Affiliation(s)
- Wei Cheng
- National Education Minister Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China.,Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China.,Department of Plant Pathology, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China
| | - Menglan Lin
- National Education Minister Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China.,Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
| | - Min Qiu
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China.,The Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, Jiangsu, 210095, China
| | - Liang Kong
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China.,The Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, Jiangsu, 210095, China
| | - Yuanpeng Xu
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China.,The Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, Jiangsu, 210095, China
| | - Yaning Li
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China.,The Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, Jiangsu, 210095, China
| | - Yan Wang
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China.,The Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, Jiangsu, 210095, China
| | - Wenwu Ye
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China.,The Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, Jiangsu, 210095, China
| | - Suomeng Dong
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China.,The Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, Jiangsu, 210095, China
| | - Shuilin He
- National Education Minister Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China.,Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
| | - Yuanchao Wang
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China.,The Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, Jiangsu, 210095, China
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7
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Nawaz K, Shahid AA, Bengyella L, Subhani MN, Ali M, Anwar W, Iftikhar S, Ali SW. Evidence of genetically diverse virulent mating types of Phytophthora capsici from Capsicum annum L. World J Microbiol Biotechnol 2018; 34:130. [PMID: 30101403 DOI: 10.1007/s11274-018-2511-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 07/28/2018] [Indexed: 11/25/2022]
Abstract
Chili pepper (Capsicum annum L.) is an important economic crop that is severely destroyed by the filamentous oomycete Phytophthora capsici. Little is known about this pathogen in key chili pepper farms in Punjab province, Pakistan. We investigated the genetic diversity of P. capsici strains using standard taxonomic and molecular tools, and characterized their colony growth patterns as well as their disease severity on chili pepper plants under the greenhouse conditions. Phylogenetic analysis based on ribosomal DNA (rDNA), β-tubulin and translation elongation factor 1α loci revealed divergent evolution in the population structure of P. capsici isolates. The mean oospore diameter of mating type A1 isolates was greater than that of mating type A2 isolates. We provide first evidence of an uneven distribution of highly virulent mating type A1 and A2 of P. capsici that are insensitive to mefenoxam, pyrimorph, dimethomorph, and azoxystrobin fungicides, and represent a risk factor that could ease outpacing the current P. capsici management strategies.
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Affiliation(s)
- Kiran Nawaz
- Institute of Agricultural Science, University of the Punjab, Lahore, Pakistan.
| | - Ahmad Ali Shahid
- Institute of Agricultural Science, University of the Punjab, Lahore, Pakistan
- Centre of Excellence in Molecular Biology, University of the Punjab, Lahore, Pakistan
| | - Louis Bengyella
- Tree Fruit Research and Extension Center (TFREC), College of Agricultural, Human and Natural Resource Sciences (CAHNRS), Washington State University, Wenatchee, USA.
- Department of Biological Control, Advanced Biotech Cooperative, Bali-Nyonga, Cameroon.
| | | | - Muhammad Ali
- Institute of Agricultural Science, University of the Punjab, Lahore, Pakistan
| | - Waheed Anwar
- Institute of Agricultural Science, University of the Punjab, Lahore, Pakistan
| | - Sehrish Iftikhar
- Institute of Agricultural Science, University of the Punjab, Lahore, Pakistan
| | - Shinawar Waseem Ali
- Institute of Agricultural Science, University of the Punjab, Lahore, Pakistan
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8
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An LRR receptor kinase regulates growth, development and pathogenesis in Phytophthora capsici. Microbiol Res 2017; 198:8-15. [DOI: 10.1016/j.micres.2017.01.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 11/27/2016] [Accepted: 01/23/2017] [Indexed: 11/20/2022]
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9
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Liu P, Li B, Lin M, Chen G, Ding X, Weng Q, Chen Q. Phosphite-induced reactive oxygen species production and ethylene and ABA biosynthesis, mediate the control of Phytophthora capsici in pepper (Capsicum annuum). FUNCTIONAL PLANT BIOLOGY : FPB 2016; 43:563-574. [PMID: 32480486 DOI: 10.1071/fp16006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 04/15/2016] [Indexed: 06/11/2023]
Abstract
Phytophthora capsici is an oomycete pathogen with a broad host range that inflicts significant damage in vegetables. Phosphite (Phi) is used to control oomycete diseases, but the molecular mechanisms underlying Phi-induced resistance to P. capsici are unknown. Thus, Phi-inhibited mycelial growth on strain LT1534 and primed host defence were analysed. We demonstrated that Phi (>5µgmL-1) had a direct antibiotic effect on mycelial growth and zoospore production, and that mortality and DNA content were significantly reduced by pre-treatment with Phi. In addition, elevated hydrogen peroxide (H2O2) promoted callose deposition and increased the levels of soluble proteins and Capsicum annuum L. pathogenesis-related 1 (CaPR1) expression. Furthermore, Phi (1gL-1) significantly increased the transcription of the antioxidant enzyme genes, and the genes involved in ethylene (ET) and abscisic acid (ABA) biosynthesis, as well as mitogen-activated protein kinase (MAPK) cascades. However, pre-treatment with reactive oxygen species (ROS), ABA and ET biosynthesis inhibitors decreased Phi-induced resistance and reduced the expression of ABA-responsive 1 (CaABR1) and lipoxygenase 1 (CaLOX1). In addition, the decreased ROS and ABA inhibited Phi-induced expression of CaMPK17-1. We propose that Phi-induced ROS production, ET and ABA biosynthesis mediate the control of P. capsici, and that ABA functions through CaMPK17-1-mediated MAPK signalling.
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Affiliation(s)
- Peiqing Liu
- Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, 350 003, China
| | - Benjin Li
- Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, 350 003, China
| | - Ming Lin
- Fujian-Taiwan Joint Innovative Centre for Ecological Control of Crop Pests, Fujian Agriculture and Forestry University, Fuzhou 350 002, China
| | - Guoliang Chen
- Fujian-Taiwan Joint Innovative Centre for Ecological Control of Crop Pests, Fujian Agriculture and Forestry University, Fuzhou 350 002, China
| | - Xueling Ding
- Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, 350 003, China
| | - Qiyong Weng
- Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, 350 003, China
| | - Qinghe Chen
- Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, 350 003, China
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