1
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Li GB, Liu J, He JX, Li GM, Zhao YD, Liu XL, Hu XH, Zhang X, Wu JL, Shen S, Liu XX, Zhu Y, He F, Gao H, Wang H, Zhao JH, Li Y, Huang F, Huang YY, Zhao ZX, Zhang JW, Zhou SX, Ji YP, Pu M, He M, Chen X, Wang J, Li W, Wu XJ, Ning Y, Sun W, Xu ZJ, Wang WM, Fan J. Rice false smut virulence protein subverts host chitin perception and signaling at lemma and palea for floral infection. THE PLANT CELL 2024; 36:2000-2020. [PMID: 38299379 PMCID: PMC11062437 DOI: 10.1093/plcell/koae027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 12/13/2023] [Accepted: 12/18/2023] [Indexed: 02/02/2024]
Abstract
The flower-infecting fungus Ustilaginoidea virens causes rice false smut, which is a severe emerging disease threatening rice (Oryza sativa) production worldwide. False smut not only reduces yield, but more importantly produces toxins on grains, posing a great threat to food safety. U. virens invades spikelets via the gap between the 2 bracts (lemma and palea) enclosing the floret and specifically infects the stamen and pistil. Molecular mechanisms for the U. virens-rice interaction are largely unknown. Here, we demonstrate that rice flowers predominantly employ chitin-triggered immunity against U. virens in the lemma and palea, rather than in the stamen and pistil. We identify a crucial U. virens virulence factor, named UvGH18.1, which carries glycoside hydrolase activity. Mechanistically, UvGH18.1 functions by binding to and hydrolyzing immune elicitor chitin and interacting with the chitin receptor CHITIN ELICITOR BINDING PROTEIN (OsCEBiP) and co-receptor CHITIN ELICITOR RECEPTOR KINASE1 (OsCERK1) to impair their chitin-induced dimerization, suppressing host immunity exerted at the lemma and palea for gaining access to the stamen and pistil. Conversely, pretreatment on spikelets with chitin induces a defense response in the lemma and palea, promoting resistance against U. virens. Collectively, our data uncover a mechanism for a U. virens virulence factor and the critical location of the host-pathogen interaction in flowers and provide a potential strategy to control rice false smut disease.
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Affiliation(s)
- Guo-Bang Li
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
- Rice Research Institute, Sichuan Agricultural University, Chengdu 611130, China
| | - Jie Liu
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Jia-Xue He
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Gao-Meng Li
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Ya-Dan Zhao
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Xiao-Ling Liu
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Xiao-Hong Hu
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
- Ecological Security and Protection Key Laboratory of Sichuan Province, Mianyang Normal University, Mianyang 621023, China
| | - Xin Zhang
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Jin-Long Wu
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Shuai Shen
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Xin-Xian Liu
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Yong Zhu
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Feng He
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Han Gao
- College of Plant Protection and the Ministry of Agriculture Key Laboratory of Pest Monitoring and Green Management, China Agricultural University, Beijing 100193, China
| | - He Wang
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Jing-Hao Zhao
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Yan Li
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Fu Huang
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Yan-Yan Huang
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Zhi-Xue Zhao
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Ji-Wei Zhang
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Shi-Xin Zhou
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Yun-Peng Ji
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Mei Pu
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Min He
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Xuewei Chen
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Jing Wang
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Weitao Li
- Rice Research Institute, Sichuan Agricultural University, Chengdu 611130, China
| | - Xian-Jun Wu
- Rice Research Institute, Sichuan Agricultural University, Chengdu 611130, China
| | - Yuese Ning
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Wenxian Sun
- College of Plant Protection and the Ministry of Agriculture Key Laboratory of Pest Monitoring and Green Management, China Agricultural University, Beijing 100193, China
| | - Zheng-Jun Xu
- Rice Research Institute, Sichuan Agricultural University, Chengdu 611130, China
| | - Wen-Ming Wang
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
| | - Jing Fan
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu 611130, China
- Yazhouwan National Laboratory, Sanya 572024, China
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2
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Nielsen MR, Sørensen JL. Investigating Fungal Biosynthetic Pathways Using Heterologous Gene Expression: Fusarium sp. as a Heterologous Host. Methods Mol Biol 2022; 2489:53-74. [PMID: 35524045 DOI: 10.1007/978-1-0716-2273-5_4] [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] [Indexed: 06/14/2023]
Abstract
Heterologous expression of uncharacterized biosynthetic gene clusters is a popular strategy for exploring the chemical potential of filamentous fungi. Here, we describe the process of PCR-amplifying fungal gene clusters and re-assembling them in a cloning vector via target-associated recombination in Saccharomyces cerevisiae . The gene cluster-carrying construct is validated and used to transform protoplasts of Fusarium graminearum , a well-studied host that is able to express the gene cluster. Chemical analysis of transformants expressing biosynthetic genes can lead to the detection and isolation of novel compounds, such as polyketides.
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Affiliation(s)
- Mikkel Rank Nielsen
- Department of Chemistry and Bioscience, Aalborg University Esbjerg, Esbjerg, Denmark.
| | - Jens Laurids Sørensen
- Department of Chemistry and Bioscience, Aalborg University Esbjerg, Esbjerg, Denmark
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3
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What is the role of the nitrate reductase (euknr) gene in fungi that live in nitrate-free environments? A targeted gene knock-out study in Ampelomyces mycoparasites. Fungal Biol 2021; 125:905-913. [PMID: 34649677 DOI: 10.1016/j.funbio.2021.06.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 05/22/2021] [Accepted: 06/10/2021] [Indexed: 11/24/2022]
Abstract
Mycoparasitic fungi can be utilized as biocontrol agents (BCAs) of many plant pathogens. Deciphering the molecular mechanisms of mycoparasitism may improve biocontrol efficiency. This work reports the first functional genetic studies in Ampelomyces, widespread mycoparasites and BCAs of powdery mildew fungi, and a molecular genetic toolbox for future works. The nitrate reductase (euknr) gene was targeted to reveal the biological function of nitrate assimilation in Ampelomyces. These mycoparasites live in an apparently nitrate-free environment, i.e. inside the hyphae of powdery mildew fungi that lack any nitrate uptake and assimilation system. Homologous recombination-based gene knock-out (KO) was applied to eliminate the euknr gene using Agrobacterium tumefaciens-mediated transformation. Efficient KO of euknr was confirmed by PCR, and visible phenotype caused by loss of euknr was detected on media with different nitrogen sources. Mycoparasitic ability was not affected by knocking out euknr as a tested transformant readily parasitized Blumeria graminis and Podosphaera xanthii colonies on barley and cucumber, respectively, and the rate of mycoparasitism did not differ from the wild type. These results indicate that euknr is not involved in mycoparasitism. Dissimilatory processes, involvement in nitric oxide metabolism, or other, yet undiscovered processes may explain why a functional euknr is maintained in Ampelomyces.
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4
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Medina EM, Robinson KA, Bellingham-Johnstun K, Ianiri G, Laplante C, Fritz-Laylin LK, Buchler NE. Genetic transformation of Spizellomyces punctatus, a resource for studying chytrid biology and evolutionary cell biology. eLife 2020; 9:52741. [PMID: 32392127 PMCID: PMC7213984 DOI: 10.7554/elife.52741] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 04/23/2020] [Indexed: 02/07/2023] Open
Abstract
Chytrids are early-diverging fungi that share features with animals that have been lost in most other fungi. They hold promise as a system to study fungal and animal evolution, but we lack genetic tools for hypothesis testing. Here, we generated transgenic lines of the chytrid Spizellomyces punctatus, and used fluorescence microscopy to explore chytrid cell biology and development during its life cycle. We show that the chytrid undergoes multiple rounds of synchronous nuclear division, followed by cellularization, to create and release many daughter ‘zoospores’. The zoospores, akin to animal cells, crawl using actin-mediated cell migration. After forming a cell wall, polymerized actin reorganizes into fungal-like cortical patches and cables that extend into hyphal-like structures. Actin perinuclear shells form each cell cycle and polygonal territories emerge during cellularization. This work makes Spizellomyces a genetically tractable model for comparative cell biology and understanding the evolution of fungi and early eukaryotes.
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Affiliation(s)
- Edgar M Medina
- University of Program in Genetics and Genomics, Duke University, Durham, United States.,Department of Molecular Genetics and Microbiology, Duke University, Durham, United States
| | - Kristyn A Robinson
- Department of Biology, University of Massachusetts, Amherst, United States
| | | | - Giuseppe Ianiri
- Department of Molecular Genetics and Microbiology, Duke University, Durham, United States
| | - Caroline Laplante
- Department of Molecular Biomedical Sciences, North Carolina State University, Raleigh, United States
| | | | - Nicolas E Buchler
- Department of Molecular Biomedical Sciences, North Carolina State University, Raleigh, United States
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5
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Jin Y, Zhao JH, Zhao P, Zhang T, Wang S, Guo HS. A fungal milRNA mediates epigenetic repression of a virulence gene in Verticillium dahliae. Philos Trans R Soc Lond B Biol Sci 2020; 374:20180309. [PMID: 30967013 DOI: 10.1098/rstb.2018.0309] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
MiRNAs in animals and plants play crucial roles in diverse developmental processes under both normal and stress conditions. miRNA-like small RNAs (milRNAs) identified in some fungi remain functionally uncharacterized. Here, we identified a number of milRNAs in Verticillium dahliae, a soil-borne fungal pathogen responsible for devastating wilt diseases in many crops. Accumulation of a V. dahliae milRNA1, named VdmilR1, was detected by RNA gel blotting. We show that the precursor gene VdMILR1 is transcribed by RNA polymerase II and is able to produce the mature VdmilR1, in a process independent of V. dahliae DCL (Dicer-like) and AGO (Argonaute) proteins. We found that an RNaseIII domain-containing protein, VdR3, is essential for V. dahliae and participates in VdmilR1 biogenesis. VdmilR1 targets a hypothetical protein-coding gene, VdHy1, at the 3'UTR for transcriptional repression through increased histone H3K9 methylation of VdHy1. Pathogenicity analysis reveals that VdHy1 is essential for fungal virulence. Together with the time difference in the expression patterns of VdmilR1 and VdHy1 during fungal infection in cotton plants, our findings identify a novel milRNA, VdmilR1, in V. dahliae synthesized by a noncanonical pathway that plays a regulatory role in pathogenicity and uncover an epigenetic mechanism for VdmilR1 in regulating a virulence target gene. This article is part of the theme issue 'Biotic signalling sheds light on smart pest management'.
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Affiliation(s)
- Yun Jin
- 1 State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences , Beijing 100101 , People's Republic of China
| | - Jian-Hua Zhao
- 1 State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences , Beijing 100101 , People's Republic of China
| | - Pan Zhao
- 1 State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences , Beijing 100101 , People's Republic of China
| | - Tao Zhang
- 1 State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences , Beijing 100101 , People's Republic of China
| | - Sheng Wang
- 1 State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences , Beijing 100101 , People's Republic of China.,2 College of Life Sciences, University of the Chinese Academy of Sciences , Beijing 100049 , People's Republic of China
| | - Hui-Shan Guo
- 1 State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences , Beijing 100101 , People's Republic of China.,2 College of Life Sciences, University of the Chinese Academy of Sciences , Beijing 100049 , People's Republic of China
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6
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Heterologous expression of intact biosynthetic gene clusters in Fusarium graminearum. Fungal Genet Biol 2019; 132:103248. [DOI: 10.1016/j.fgb.2019.103248] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 06/27/2019] [Accepted: 06/27/2019] [Indexed: 11/18/2022]
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7
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Zhang YZ, Chen Q, Liu CH, Lei L, Li Y, Zhao K, Wei MQ, Guo ZR, Wang Y, Xu BJ, Jiang YF, Kong L, Liu YL, Lan XJ, Jiang QT, Ma J, Wang JR, Chen GY, Wei YM, Zheng YL, Qi PF. Fusarium graminearum FgCWM1 Encodes a Cell Wall Mannoprotein Conferring Sensitivity to Salicylic Acid and Virulence to Wheat. Toxins (Basel) 2019; 11:toxins11110628. [PMID: 31671876 PMCID: PMC6891299 DOI: 10.3390/toxins11110628] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 10/23/2019] [Accepted: 10/24/2019] [Indexed: 11/30/2022] Open
Abstract
Fusarium graminearum causes Fusarium head blight (FHB), a devastating disease of wheat. Salicylic acid (SA) is involved in the resistance of wheat to F. graminearum. Cell wall mannoprotein (CWM) is known to trigger defense responses in plants, but its role in the pathogenicity of F. graminearum remains unclear. Here, we characterized FgCWM1 (FG05_11315), encoding a CWM in F. graminearum. FgCWM1 was highly expressed in wheat spikes by 24 h after initial inoculation and was upregulated by SA. Disruption of FgCWM1 (ΔFgCWM1) reduced mannose and protein accumulation in the fungal cell wall, especially under SA treatment, and resulted in defective fungal cell walls, leading to increased fungal sensitivity to SA. The positive role of FgCWM1 in mannose and protein accumulation was confirmed by its expression in Saccharomyces cerevisiae. Compared with wild type (WT), ΔFgCWM1 exhibited reduced pathogenicity toward wheat, but it produced the same amount of deoxynivalenol both in culture and in spikes. Complementation of ΔFgCWM1 with FgCWM1 restored the WT phenotype. Localization analyses revealed that FgCWM1 was distributed on the cell wall, consistent with its structural role. Thus, FgCWM1 encodes a CWM protein that plays an important role in the cell wall integrity and pathogenicity of F. graminearum.
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Affiliation(s)
- Ya-Zhou 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.
| | - Qing Chen
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu 611130, Sichuan, China.
| | - Cai-Hong Liu
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu 611130, Sichuan, China.
| | - Lu Lei
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu 611130, Sichuan, China.
| | - Yang Li
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu 611130, Sichuan, China.
| | - Kan Zhao
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu 611130, Sichuan, China.
| | - Mei-Qiao Wei
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu 611130, Sichuan, China.
| | - Zhen-Ru Guo
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu 611130, Sichuan, China.
| | - Yan Wang
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu 611130, Sichuan, China.
| | - Bin-Jie Xu
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu 611130, Sichuan, China.
| | - Yun-Feng Jiang
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu 611130, Sichuan, China.
| | - Li Kong
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu 611130, Sichuan, China.
| | - Yan-Lin Liu
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu 611130, Sichuan, China.
| | - Xiu-Jin Lan
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu 611130, Sichuan, China.
| | - Qian-Tao 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
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu 611130, Sichuan, China.
| | - Ji-Rui Wang
- 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.
| | - Guo-Yue 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.
| | - Yu-Ming 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.
| | - You-Liang 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.
| | - Peng-Fei Qi
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu 611130, Sichuan, China.
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8
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Nielsen MR, Sondergaard TE, Giese H, Sørensen JL. Advances in linking polyketides and non-ribosomal peptides to their biosynthetic gene clusters in Fusarium. Curr Genet 2019; 65:1263-1280. [DOI: 10.1007/s00294-019-00998-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 05/20/2019] [Accepted: 05/22/2019] [Indexed: 11/24/2022]
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9
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Functional Analysis of FgNahG Clarifies the Contribution of Salicylic Acid to Wheat ( Triticum aestivum) Resistance against Fusarium Head Blight. Toxins (Basel) 2019; 11:toxins11020059. [PMID: 30678154 PMCID: PMC6410203 DOI: 10.3390/toxins11020059] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2018] [Revised: 12/20/2018] [Accepted: 01/11/2019] [Indexed: 02/02/2023] Open
Abstract
Salicylic acid (SA) is a key defense hormone associated with wheat resistance against Fusarium head blight, which is a severe disease mainly caused by Fusarium graminearum. Although F. graminearum can metabolize SA, it remains unclear how this metabolic activity affects the wheat–F. graminearum interaction. In this study, we identified a salicylate hydroxylase gene (FG05_08116; FgNahG) in F. graminearum. This gene encodes a protein that catalyzes the conversion of SA to catechol. Additionally, FgNahG was widely distributed within hyphae. Disrupting the FgNahG gene (ΔFgNahG) led to enhanced sensitivity to SA, increased accumulation of SA in wheat spikes during the early infection stage and inhibited development of head blight symptoms. However, FgNahG did not affect mycotoxin production. Re-introducing a functional FgNahG gene into the ΔFgNahG mutant recovered the wild-type phenotype. Moreover, the expression of FgNahG in transgenic Arabidopsis thaliana decreased the SA concentration and the resistance of leaves to F. graminearum. These results indicate that the endogenous SA in wheat influences the resistance against F. graminearum. Furthermore, the capacity to metabolize SA is an important factor affecting the ability of F. graminearum to infect wheat plants.
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10
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Rocheleau H, Al-Harthi R, Ouellet T. Degradation of salicylic acid by Fusarium graminearum. Fungal Biol 2018; 123:77-86. [PMID: 30654960 DOI: 10.1016/j.funbio.2018.11.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 10/23/2018] [Accepted: 11/08/2018] [Indexed: 12/20/2022]
Abstract
Fusarium head blight (FHB) is a major cereal crop disease, caused most frequently by the fungus Fusarium graminearum. We have previously demonstrated that F. graminearum can utilize SA as sole source of carbon to grow. In this current study, we further characterized selected four fungal SA-responsive genes that are predicted to encode salicylic acid (SA)-degrading enzymes and we used a gene replacement approach to characterize them further. These included two genes predicted to encode a salicylate 1-monooxygenase, FGSG_03657 and FGSG_09063, a catechol 1, 2-dioxygenase gene, FGSG_03667, and a 2, 3-dihydroxybenzoic acid decarboxylase gene, FGSG_09061. For each gene, three independent gene replacement strains were assayed for their ability to degrade salicylic acid in liquid culture. Salicylate 1-monooxygenase FGSG_03657 and catechol 1, 2-dioxygenase FGSG_03667 were shown to be essential for SA degradation, while a loss of 2, 3-dihydroxybenzoic acid decarboxylase FGSG_09061 caused only a partial reduction of SA degradation and a loss of salicylate 1-monooxygenase FGSG_09063 had no effect when compared to wild type culture. Salicylate 1-monooxygenase FGSG_03657 and catechol 1, 2-dioxygenase FGSG_03667 were identified as the first two key enzyme steps of SA degradation via catechol in the β-ketoadipate pathway. Expression profiles for all four genes were also determined in liquid culture and in planta. Salicylate 1-monooxygenase FGSG_03657 and catechol 1, 2-dioxygenase FGSG_03667 were co-expressed and their expression was substrate dependent in liquid culture; however their expression was uncoupled in planta. Disruption of the gene for catechol 1, 2-dioxygenase FGSG_03667 was shown to have no effect on fungal virulence on wheat. Our results with 2, 3-dihydroxybenzoic acid decarboxylase FGSG_09061 raise the possibility of an alternate non-oxidative decarboxylation pathway for the conversion of SA to catechol via 2, 3-dihydrozybenzoic acid and for a connection between the oxidative and the non-oxidative decarboxylation pathways for SA conversion.
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Affiliation(s)
- Hélène Rocheleau
- Ottawa Research and Development Centre, Agriculture and Agri-Food Canada, 960 Carling Ave, Ottawa, ON K1A 0C6, Canada.
| | - Reem Al-Harthi
- Ottawa Research and Development Centre, Agriculture and Agri-Food Canada, 960 Carling Ave, Ottawa, ON K1A 0C6, Canada; Department of Biology, University of Ottawa, 30 Marie Currie, Ottawa, ON K1N 6N5, Canada.
| | - Thérèse Ouellet
- Ottawa Research and Development Centre, Agriculture and Agri-Food Canada, 960 Carling Ave, Ottawa, ON K1A 0C6, Canada.
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11
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Bahadoor A, Brauer EK, Bosnich W, Schneiderman D, Johnston A, Aubin Y, Blackwell B, Melanson JE, Harris LJ. Gramillin A and B: Cyclic Lipopeptides Identified as the Nonribosomal Biosynthetic Products of Fusarium graminearum. J Am Chem Soc 2018; 140:16783-16791. [PMID: 30395461 DOI: 10.1021/jacs.8b10017] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The virulence and broad host range of Fusarium graminearum is associated with its ability to secrete an arsenal of phytotoxic secondary metabolites, including the regulated mycotoxins belonging to the deoxynivalenol family. The TRI genes responsible for the biosynthesis of deoxynivalenol and related compounds are usually expressed during fungal infection. However, the F. graminearum genome harbors an array of unexplored biosynthetic gene clusters that are also co-induced with the TRI genes, including the nonribosomal peptide synthetase 8 ( NRPS8) gene cluster. Here, we identify two bicyclic lipopeptides, gramillin A (1) and B (2), as the biosynthetic end products of NRPS8. Structural elucidation by high-resolution LC-MS and NMR, including 1H-15N-13C HNCO and HNCA on isotopically enriched compounds, revealed that the gramillins possess a fused bicyclic structure with ring closure of the main peptide macrocycle occurring via an anhydride bond. Through targeted gene disruption, we characterized the GRA1 biosynthetic gene and its transcription factor GRA2 in the NRPS8 gene cluster. Further, we show that the gramillins are produced in planta on maize silks, promoting fungal virulence on maize but have no discernible effect on wheat head infection. Leaf infiltration of the gramillins induces cell death in maize, but not in wheat. Our results show that F. graminearum deploys the gramillins as a virulence agent in maize, but not in wheat, thus displaying host-specific adaptation.
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Affiliation(s)
- Adilah Bahadoor
- Metrology , National Research Council Canada , Ottawa , Ontario K1A 0R6 , Canada
| | - Elizabeth K Brauer
- Ottawa Research and Development Centre , Agriculture and Agri-Food Canada , Ottawa , Ontario K1A 0C6 , Canada
| | - Whynn Bosnich
- Ottawa Research and Development Centre , Agriculture and Agri-Food Canada , Ottawa , Ontario K1A 0C6 , Canada
| | - Danielle Schneiderman
- Ottawa Research and Development Centre , Agriculture and Agri-Food Canada , Ottawa , Ontario K1A 0C6 , Canada
| | - Anne Johnston
- Ottawa Research and Development Centre , Agriculture and Agri-Food Canada , Ottawa , Ontario K1A 0C6 , Canada
| | - Yves Aubin
- Centre for Biologics Evaluation, Biologics, and Genetic Therapies Directorate , Health Canada , Ottawa , Ontario K1A 0K9 , Canada
| | - Barbara Blackwell
- Ottawa Research and Development Centre , Agriculture and Agri-Food Canada , Ottawa , Ontario K1A 0C6 , Canada
| | - Jeremy E Melanson
- Metrology , National Research Council Canada , Ottawa , Ontario K1A 0R6 , Canada
| | - Linda J Harris
- Ottawa Research and Development Centre , Agriculture and Agri-Food Canada , Ottawa , Ontario K1A 0C6 , Canada
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12
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Westphal KR, Muurmann AT, Paulsen IE, Nørgaard KTH, Overgaard ML, Dall SM, Aalborg T, Wimmer R, Sørensen JL, Sondergaard TE. Who Needs Neighbors? PKS8 Is a Stand-Alone Gene in Fusarium graminearum Responsible for Production of Gibepyrones and Prolipyrone B. Molecules 2018; 23:E2232. [PMID: 30200525 PMCID: PMC6225250 DOI: 10.3390/molecules23092232] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 08/28/2018] [Accepted: 09/01/2018] [Indexed: 01/13/2023] Open
Abstract
Genome sequencing of the genus Fusarium has revealed a great capacity for discovery of new natural products of potential economical and therapeutic importance. Several of these are unknown. In this study, we investigated the product of the PKS8 gene in Fusarium graminearum, which was recently linked to gibepyrones in F. fujikuroi. Genomic analyses showed that PKS8 constitutes a stand-alone gene in F. graminearum and related species. Overexpression of PKS8 resulted in production of gibepyrones A, B, D, G and prolipyrone B, which could not be detected in the wild type strain. Our results suggest that PKS8 produces the entry compound gibepyrone A, which is subsequently oxidized by one or several non-clustering cytochrome P450 monooxygenases ending with prolipyrone B.
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Affiliation(s)
| | | | - Iben Engell Paulsen
- Department of Chemistry and Bioscience, Aalborg University, 9100 Aalborg, Denmark.
| | | | - Marie Lund Overgaard
- Department of Chemistry and Bioscience, Aalborg University, 9100 Aalborg, Denmark.
| | | | - Trine Aalborg
- Department of Chemistry and Bioscience, Aalborg University, 9100 Aalborg, Denmark.
| | - Reinhard Wimmer
- Department of Chemistry and Bioscience, Aalborg University, 9100 Aalborg, Denmark.
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13
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Marton K, Flajšman M, Radišek S, Košmelj K, Jakše J, Javornik B, Berne S. Comprehensive analysis of Verticillium nonalfalfae in silico secretome uncovers putative effector proteins expressed during hop invasion. PLoS One 2018; 13:e0198971. [PMID: 29894496 PMCID: PMC5997321 DOI: 10.1371/journal.pone.0198971] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 05/28/2018] [Indexed: 12/22/2022] Open
Abstract
The vascular plant pathogen Verticillium nonalfalfae causes Verticillium wilt in several important crops. VnaSSP4.2 was recently discovered as a V. nonalfalfae virulence effector protein in the xylem sap of infected hop. Here, we expanded our search for candidate secreted effector proteins (CSEPs) in the V. nonalfalfae predicted secretome using a bioinformatic pipeline built on V. nonalfalfae genome data, RNA-Seq and proteomic studies of the interaction with hop. The secretome, rich in carbohydrate active enzymes, proteases, redox proteins and proteins involved in secondary metabolism, cellular processing and signaling, includes 263 CSEPs. Several homologs of known fungal effectors (LysM, NLPs, Hce2, Cerato-platanins, Cyanovirin-N lectins, hydrophobins and CFEM domain containing proteins) and avirulence determinants in the PHI database (Avr-Pita1 and MgSM1) were found. The majority of CSEPs were non-annotated and were narrowed down to 44 top priority candidates based on their likelihood of being effectors. These were examined by spatio-temporal gene expression profiling of infected hop. Among the highest in planta expressed CSEPs, five deletion mutants were tested in pathogenicity assays. A deletion mutant of VnaUn.279, a lethal pathotype specific gene with sequence similarity to SAM-dependent methyltransferase (LaeA), had lower infectivity and showed highly reduced virulence, but no changes in morphology, fungal growth or conidiation were observed. Several putative secreted effector proteins that probably contribute to V. nonalfalfae colonization of hop were identified in this study. Among them, LaeA gene homolog was found to act as a potential novel virulence effector of V. nonalfalfae. The combined results will serve for future characterization of V. nonalfalfae effectors, which will advance our understanding of Verticillium wilt disease.
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Affiliation(s)
- Kristina Marton
- Department of Agronomy, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Marko Flajšman
- Department of Agronomy, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | | | - Katarina Košmelj
- Department of Agronomy, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Jernej Jakše
- Department of Agronomy, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Branka Javornik
- Department of Agronomy, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Sabina Berne
- Department of Agronomy, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
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14
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Abstract
Accumulating evidence indicates that small noncoding RNAs (sRNAs) can be transferred across species for interkingdom communication. In addition to the artificial transgene-derived small interfering RNAs (siRNAs), endogenous microRNAs (miRNAs) can also influence interacting organisms to execute a regulatory function. For instance, we have recently found that, in response to infection with Verticillium dahliae (V. dahliae), cotton plants increase accumulation of miR166 and miR159, which can be exported to the fungal hyphae for specific silencing of virulence genes. These findings suggest a great potential for applying interkingdom mobile miRNAs for crop protection against fungal pathogens. The methods described here provide an approach to identify plant miRNAs and their potential targets in invading fungal pathogens, which will help in revealing the underlying mechanisms of these crosstalk phenomena.
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Affiliation(s)
- Yun Jin
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Hui-Shan Guo
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China.
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15
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Idnurm A, Bailey AM, Cairns TC, Elliott CE, Foster GD, Ianiri G, Jeon J. A silver bullet in a golden age of functional genomics: the impact of Agrobacterium-mediated transformation of fungi. Fungal Biol Biotechnol 2017; 4:6. [PMID: 28955474 PMCID: PMC5615635 DOI: 10.1186/s40694-017-0035-0] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 09/18/2017] [Indexed: 11/10/2022] Open
Abstract
The implementation of Agrobacterium tumefaciens as a transformation tool revolutionized approaches to discover and understand gene functions in a large number of fungal species. A. tumefaciens mediated transformation (AtMT) is one of the most transformative technologies for research on fungi developed in the last 20 years, a development arguably only surpassed by the impact of genomics. AtMT has been widely applied in forward genetics, whereby generation of strain libraries using random T-DNA insertional mutagenesis, combined with phenotypic screening, has enabled the genetic basis of many processes to be elucidated. Alternatively, AtMT has been fundamental for reverse genetics, where mutant isolates are generated with targeted gene deletions or disruptions, enabling gene functional roles to be determined. When combined with concomitant advances in genomics, both forward and reverse approaches using AtMT have enabled complex fungal phenotypes to be dissected at the molecular and genetic level. Additionally, in several cases AtMT has paved the way for the development of new species to act as models for specific areas of fungal biology, particularly in plant pathogenic ascomycetes and in a number of basidiomycete species. Despite its impact, the implementation of AtMT has been uneven in the fungi. This review provides insight into the dynamics of expansion of new research tools into a large research community and across multiple organisms. As such, AtMT in the fungi, beyond the demonstrated and continuing power for gene discovery and as a facile transformation tool, provides a model to understand how other technologies that are just being pioneered, e.g. CRISPR/Cas, may play roles in fungi and other eukaryotic species.
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Affiliation(s)
- Alexander Idnurm
- School of BioSciences, University of Melbourne, Melbourne, VIC 3010 Australia
| | - Andy M. Bailey
- School of Biological Sciences, University of Bristol, Bristol, UK
| | - Timothy C. Cairns
- Department of Applied and Molecular Microbiology, Technische Universität Berlin, Berlin, Germany
| | - Candace E. Elliott
- School of BioSciences, University of Melbourne, Melbourne, VIC 3010 Australia
| | - Gary D. Foster
- School of Biological Sciences, University of Bristol, Bristol, UK
| | - Giuseppe Ianiri
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, USA
| | - Junhyun Jeon
- College of Life and Applied Sciences, Yeungnam University, Gyeongsan, South Korea
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16
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A new and efficient approach for construction of uridine/uracil auxotrophic mutants in the filamentous fungus Aspergillus oryzae using Agrobacterium tumefaciens-mediated transformation. World J Microbiol Biotechnol 2017; 33:107. [DOI: 10.1007/s11274-017-2275-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 04/26/2017] [Indexed: 10/19/2022]
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17
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Zhang YZ, Wei ZZ, Liu CH, Chen Q, Xu BJ, Guo ZR, Cao YL, Wang Y, Han YN, Chen C, Feng X, Qiao YY, Zong LJ, Zheng T, Deng M, Jiang QT, Li W, Zheng YL, Wei YM, Qi PF. Linoleic acid isomerase gene FgLAI12 affects sensitivity to salicylic acid, mycelial growth and virulence of Fusarium graminearum. Sci Rep 2017; 7:46129. [PMID: 28387243 PMCID: PMC5384231 DOI: 10.1038/srep46129] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Accepted: 03/13/2017] [Indexed: 11/09/2022] Open
Abstract
Fusarium graminearum is the major causal agent of fusarium head blight in wheat, a serious disease worldwide. Linoleic acid isomerase (LAI) catalyses the transformation of linoleic acid (LA) to conjugated linoleic acid (CLA), which is beneficial for human health. We characterised a cis-12 LAI gene of F. graminearum (FGSG_02668; FgLAI12), which was downregulated by salicylic acid (SA), a plant defence hormone. Disruption of FgLAI12 in F. graminearum resulted in decreased accumulation of cis-9,trans-11 CLA, enhanced sensitivity to SA, and increased accumulation of LA and SA in wheat spikes during infection. In addition, mycelial growth, accumulation of deoxynivalenol, and pathogenicity in wheat spikes were reduced. Re-introduction of a functional FgLAI12 gene into ΔFgLAI12 recovered the wild-type phenotype. Fluorescent microscopic analysis showed that FgLAI12 protein was usually expressed in the septa zone of conidia and the vacuole of hyphae, but was expressed in the cell membrane of hyphae in response to exogenous LA, which may be an element of LA metabolism during infection by F. graminearum. The cis-12 LAI enzyme encoded by FgLAI12 is critical for fungal response to SA, mycelial growth and virulence in wheat. The gene FgLAI12 is potentially valuable for biotechnological synthesis of cis-9,trans-11 CLA.
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Affiliation(s)
- Ya-Zhou Zhang
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Zhen-Zhen Wei
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Cai-Hong Liu
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Qing Chen
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Bin-Jie Xu
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Zhen-Ru Guo
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Yong-Li Cao
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Yan Wang
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Ya-Nan Han
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Chen Chen
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Xiang Feng
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Yuan-Yuan Qiao
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Lu-Juan Zong
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Ting Zheng
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Mei Deng
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Qian-Tao Jiang
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Wei Li
- Agronomy College, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - You-Liang Zheng
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Yu-Ming Wei
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Peng-Fei Qi
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
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18
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Qi X, Liu C, Song L, Li Y, Li M. PaCYP78A9, a Cytochrome P450, Regulates Fruit Size in Sweet Cherry ( Prunus avium L.). FRONTIERS IN PLANT SCIENCE 2017; 8:2076. [PMID: 29259616 PMCID: PMC5723407 DOI: 10.3389/fpls.2017.02076] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 11/20/2017] [Indexed: 05/21/2023]
Abstract
Sweet cherry (Prunus avium L.) is an important fruit crop in which fruit size is strongly associated with commercial value; few genes associated with fruit size have, however, been identified in sweet cherry. Members of the CYP78A subfamily, a group of important cytochrome P450s, have been found to be involved in controlling seed size and development in Arabidopsis thaliana, rice, soybean, and tomato. However, the influence of CYP78A members in controlling organ size and the underlying molecular mechanisms in sweet cherry and other fruit trees remains unclear. Here, we characterized a P. avium CYP78A gene PaCYP78A9 that is thought to be involved in the regulation of fruit size and organ development using overexpression and silencing approaches. PaCYP78A9 was significantly expressed in the flowers and fruit of sweet cherry. RNAi silencing of PaCYP78A9 produced small cherry fruits and PaCYP78A9 was found to affect fruit size by mediating mesocarp cell proliferation and expansion during fruit growth and development. Overexpression of PaCYP78A9 in Arabidopsis resulted in increased silique and seed size and PaCYP78A9 was found to be highly expressed in the inflorescences and siliques of transgenic plants. Genes related to cell cycling and proliferation were downregulated in fruit from sweet cherry TRV::PaCYP78A9-silencing lines, suggesting that PaCYP78A9 is likely to be an important upstream regulator of cell cycle processes. Together, our findings indicate that PaCYP78A9 plays an essential role in the regulation of cherry fruit size and provide insights into the molecular basis of the mechanisms regulating traits such as fruit size in P. avium.
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19
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Zhang T, Zhao YL, Zhao JH, Wang S, Jin Y, Chen ZQ, Fang YY, Hua CL, Ding SW, Guo HS. Cotton plants export microRNAs to inhibit virulence gene expression in a fungal pathogen. NATURE PLANTS 2016; 2:16153. [PMID: 27668926 DOI: 10.1038/nplants.2016.153] [Citation(s) in RCA: 285] [Impact Index Per Article: 35.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 09/06/2016] [Indexed: 05/20/2023]
Abstract
Plant pathogenic fungi represent the largest group of disease-causing agents on crop plants, and are a constant and major threat to agriculture worldwide. Recent studies have shown that engineered production of RNA interference (RNAi)-inducing dsRNA in host plants can trigger specific fungal gene silencing and confer resistance to fungal pathogens1-7. Although these findings illustrate efficient uptake of host RNAi triggers by pathogenic fungi, it is unknown whether or not such an uptake mechanism has been evolved for a natural biological function in fungus-host interactions. Here, we show that in response to infection with Verticillium dahliae (a vascular fungal pathogen responsible for devastating wilt diseases in many crops) cotton plants increase production of microRNA 166 (miR166) and miR159 and export both to the fungal hyphae for specific silencing. We found that two V. dahliae genes encoding a Ca2+-dependent cysteine protease (Clp-1) and an isotrichodermin C-15 hydroxylase (HiC-15), and targeted by miR166 and miR159, respectively, are both essential for fungal virulence. Notably, V. dahliae strains expressing either Clp-1 or HiC-15 rendered resistant to the respective miRNA exhibited drastically enhanced virulence in cotton plants. Together, our findings identify a novel defence strategy of host plants by exporting specific miRNAs to induce cross-kingdom gene silencing in pathogenic fungi and confer disease resistance.
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Affiliation(s)
- Tao Zhang
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
- College of Life Sciences, University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Yun-Long Zhao
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
- College of Life Sciences, University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Jian-Hua Zhao
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Sheng Wang
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yun Jin
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Zhong-Qi Chen
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yuan-Yuan Fang
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Chen-Lei Hua
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Shou-Wei Ding
- Department of Plant Pathology and Microbiology, Institute for Integrative Genome Biology, University of California, Riverside, California, 92521, USA
| | - Hui-Shan Guo
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
- College of Life Sciences, University of the Chinese Academy of Sciences, Beijing 100049, China
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20
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Wang S, Xing H, Hua C, Guo HS, Zhang J. An Improved Single-Step Cloning Strategy Simplifies the Agrobacterium tumefaciens-Mediated Transformation (ATMT)-Based Gene-Disruption Method for Verticillium dahliae. PHYTOPATHOLOGY 2016; 106:645-652. [PMID: 26780432 DOI: 10.1094/phyto-10-15-0280-r] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The soilborne fungal pathogen Verticillium dahliae infects a broad range of plant species to cause severe diseases. The availability of Verticillium genome sequences has provided opportunities for large-scale investigations of individual gene function in Verticillium strains using Agrobacterium tumefaciens-mediated transformation (ATMT)-based gene-disruption strategies. Traditional ATMT vectors require multiple cloning steps and elaborate characterization procedures to achieve successful gene replacement; thus, these vectors are not suitable for high-throughput ATMT-based gene deletion. Several advancements have been made that either involve simplification of the steps required for gene-deletion vector construction or increase the efficiency of the technique for rapid recombinant characterization. However, an ATMT binary vector that is both simple and efficient is still lacking. Here, we generated a USER-ATMT dual-selection (DS) binary vector, which combines both the advantages of the USER single-step cloning technique and the efficiency of the herpes simplex virus thymidine kinase negative-selection marker. Highly efficient deletion of three different genes in V. dahliae using the USER-ATMT-DS vector enabled verification that this newly-generated vector not only facilitates the cloning process but also simplifies the subsequent identification of fungal homologous recombinants. The results suggest that the USER-ATMT-DS vector is applicable for efficient gene deletion and suitable for large-scale gene deletion in V. dahliae.
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Affiliation(s)
- Sheng Wang
- All authors: State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101; and first and second authors: University of Chinese Academy of Sciences, Beijing 100049, China
| | - Haiying Xing
- All authors: State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101; and first and second authors: University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chenlei Hua
- All authors: State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101; and first and second authors: University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hui-Shan Guo
- All authors: State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101; and first and second authors: University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jie Zhang
- All authors: State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101; and first and second authors: University of Chinese Academy of Sciences, Beijing 100049, China
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21
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Toh SS, Treves DS, Barati MT, Perlin MH. Reliable transformation system for Microbotryum lychnidis-dioicae informed by genome and transcriptome project. Arch Microbiol 2016; 198:813-25. [PMID: 27215216 DOI: 10.1007/s00203-016-1244-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2016] [Revised: 05/08/2016] [Accepted: 05/16/2016] [Indexed: 10/21/2022]
Abstract
Microbotryum lychnidis-dioicae is a member of a species complex infecting host plants in the Caryophyllaceae. It is used as a model system in many areas of research, but attempts to make this organism tractable for reverse genetic approaches have not been fruitful. Here, we exploited the recently obtained genome sequence and transcriptome analysis to inform our design of constructs for use in Agrobacterium-mediated transformation techniques currently available for other fungi. Reproducible transformation was demonstrated at the genomic, transcriptional and functional levels. Moreover, these initial proof-of-principle experiments provide evidence that supports the findings from initial global transcriptome analysis regarding expression from the respective promoters under different growth conditions of the fungus. The technique thus provides for the first time the ability to stably introduce transgenes and over-express target M. lychnidis-dioicae genes.
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Affiliation(s)
- Su San Toh
- Department of Biology and Program on Disease Evolution, University of Louisville, Louisville, KY, 40292, USA
| | | | - Michelle T Barati
- Kidney Disease Program, University of Louisville, Louisville, KY, USA
| | - Michael H Perlin
- Department of Biology and Program on Disease Evolution, University of Louisville, Louisville, KY, 40292, USA.
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22
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Black perithecial pigmentation in Fusarium species is due to the accumulation of 5-deoxybostrycoidin-based melanin. Sci Rep 2016; 6:26206. [PMID: 27193384 PMCID: PMC4872168 DOI: 10.1038/srep26206] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Accepted: 04/26/2016] [Indexed: 11/30/2022] Open
Abstract
Biosynthesis of the black perithecial pigment in the filamentous fungus Fusarium graminearum is dependent on the polyketide synthase PGL1 (oPKS3). A seven-membered PGL1 gene cluster was identified by over-expression of the cluster specific transcription factor pglR. Targeted gene replacement showed that PGL1, pglJ, pglM and pglV were essential for the production of the perithecial pigment. Over-expression of PGL1 resulted in the production of 6-O-demethyl-5-deoxybostrycoidin (1), 5-deoxybostrycoidin (2), and three novel compounds 5-deoxybostrycoidin anthrone (3), 6-O-demethyl-5-deoxybostrycoidin anthrone (4) and purpurfusarin (5). The novel dimeric bostrycoidin purpurfusarin (5) was found to inhibit the growth of Candida albicans with an IC50 of 8.0 +/− 1.9 μM. The results show that Fusarium species with black perithecia have a previously undescribed form of 5-deoxybostrycoidin based melanin in their fruiting bodies.
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23
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Zhang YZ, Chen Q, Liu CH, Liu YB, Yi P, Niu KX, Wang YQ, Wang AQ, Yu HY, Pu ZE, Jiang QT, Wei YM, Qi PF, Zheng YL. Chitin synthase gene FgCHS8 affects virulence and fungal cell wall sensitivity to environmental stress in Fusarium graminearum. Fungal Biol 2016; 120:764-74. [PMID: 27109372 DOI: 10.1016/j.funbio.2016.02.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Revised: 01/30/2016] [Accepted: 02/05/2016] [Indexed: 11/18/2022]
Abstract
Fusarium graminearum is the major causal agent of Fusarium head blight (FHB) of wheat and barley and is considered to be one of the most devastating plant diseases worldwide. Chitin is a critical component of the fungal cell wall and is polymerized from UDP-N-acetyl-alpha-D-glucosamine by chitin synthase. We characterized FgCHS8, a new class of the chitin synthase gene in F. graminearum. Disruption of FgCHS8 resulted in reduced accumulation of chitin, decreased chitin synthase activity, and had no effect on conidia growth when compared with the wild-type isolate. ΔFgCHS8 had a growth rate comparable to that of the wild-type isolate in vitro. However, ΔFgCHS8 had reduced growth when grown on agar supplemented with either 0.025% SDS or 0.9 mM salicylic acid. ΔFgCHS8 produced significantly less deoxynivalenol and exhibited reduced pathogenicity in wheat spikes. Re-introduction of a functional FgCHS8 gene into the ΔFgCHS8 mutant strain restored the wild-type phenotypes. Fluorescence microscopy revealed that FgCHS8 protein was initially expressed in the septa zone, and then gradually distributed over the entire cellular membrane, indicating that FgCHS8 was required for cell wall development. Our results demonstrated that FgCHS8 is important for cell wall sensitivity to environmental stress factors and deoxynivalenol production in F. graminearum.
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Affiliation(s)
- Ya-Zhou Zhang
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.
| | - Qing Chen
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.
| | - Cai-Hong Liu
- Agronomy College, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.
| | - Yu-Bin Liu
- Agricultural Science Research Institute, Xichang, Sichuan 615000, China.
| | - Pan Yi
- Agronomy College, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.
| | - Ke-Xin Niu
- Agronomy College, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.
| | - Yan-Qing Wang
- Agronomy College, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.
| | - An-Qi Wang
- Agronomy College, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.
| | - Hai-Yue Yu
- Agronomy College, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.
| | - Zhi-En Pu
- Agronomy College, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.
| | - Qian-Tao Jiang
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.
| | - Yu-Ming Wei
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.
| | - Peng-Fei Qi
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.
| | - You-Liang Zheng
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.
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Bahadoor A, Schneiderman D, Gemmill L, Bosnich W, Blackwell B, Melanson JE, McRae G, Harris LJ. Hydroxylation of Longiborneol by a Clm2-Encoded CYP450 Monooxygenase to Produce Culmorin in Fusarium graminearum. JOURNAL OF NATURAL PRODUCTS 2016; 79:81-88. [PMID: 26673640 DOI: 10.1021/acs.jnatprod.5b00676] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A second structural gene required for culmorin biosynthesis in the plant pathogen Fusarium graminearum is described. Clm2 encodes a regio- and stereoselective cytochrome P450 monooxygenase for C-11 of longiborneol (1). Clm2 gene disruptants were grown in liquid culture and assessed for culmorin production via HPLC-evaporative light scattering detection. The analysis indicated a complete loss of culmorin (2) from the liquid culture of the ΔClm2 mutants. Culmorin production resumed in a ΔClm2 complementation experiment. A detailed analysis of the secondary metabolites extracted from the large-scale liquid culture of disruptant ΔClm2D20 revealed five new natural products: 3-hydroxylongiborneol (3), 5-hydroxylongiborneol (4), 12-hydroxylongiborneol (5), 15-hydroxylongiborneol (6), and 11-epi-acetylculmorin (7). The structures of the new compounds were elucidated by a combination of HRMS, 1D and 2D NMR, and X-ray crystallography.
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Affiliation(s)
- Adilah Bahadoor
- Ottawa Research and Development Centre, Agriculture and Agri-Food Canada , Ottawa, ON K1A 0C6 Canada
| | - Danielle Schneiderman
- Ottawa Research and Development Centre, Agriculture and Agri-Food Canada , Ottawa, ON K1A 0C6 Canada
| | - Larissa Gemmill
- Ottawa Research and Development Centre, Agriculture and Agri-Food Canada , Ottawa, ON K1A 0C6 Canada
| | - Whynn Bosnich
- Ottawa Research and Development Centre, Agriculture and Agri-Food Canada , Ottawa, ON K1A 0C6 Canada
| | - Barbara Blackwell
- Ottawa Research and Development Centre, Agriculture and Agri-Food Canada , Ottawa, ON K1A 0C6 Canada
| | - Jeremy E Melanson
- Measurement Science and Standards, National Research Council Canada , Ottawa, ON K1A 0R6 Canada
| | - Garnet McRae
- Measurement Science and Standards, National Research Council Canada , Ottawa, ON K1A 0R6 Canada
| | - Linda J Harris
- Ottawa Research and Development Centre, Agriculture and Agri-Food Canada , Ottawa, ON K1A 0C6 Canada
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Qi X, Su X, Guo H, Qi J, Cheng H. A ku70 null mutant improves gene targeting frequency in the fungal pathogen Verticillium dahliae. World J Microbiol Biotechnol 2015; 31:1889-97. [PMID: 26475327 DOI: 10.1007/s11274-015-1907-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Accepted: 07/20/2015] [Indexed: 12/17/2022]
Abstract
To overcome the challenges met with gene deletion in the plant pathogen Verticillium dahliae, a mutant strain with impaired non-homologous end joining DNA repair was generated to improve targeted gene replacement frequencies. A V. dahliae 991 ΔVdku70 null mutant strain was generated using Agrobacterium tumefaciens-mediated transformation. Despite having impaired non-homologous end joining DNA repair function, the ΔVdku70 strain exhibited normal growth, reproduction capability, and pathogenicity when compared with the wild-type strain. When the ΔVdku70 strain was used to delete 2-oxoglutarate dehydrogenase E2, ferric reductase transmembrane component 3 precursor, and ferric reductase transmembrane component 6 genes, gene replacement frequencies ranged between 22.8 and 34.7% compared with 0.3 and 0.5 % in the wild-type strain. The ΔVdku70 strain will be a valuable tool to generate deletion strains when studying factors that underlie virulence and pathogenesis in this filamentous fungus.
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Aragona M, Valente MT. Genetic transformation of the tomato pathogen Pyrenochaeta lycopersici allowed gene knockout using a split-marker approach. Curr Genet 2014; 61:211-20. [PMID: 25413737 DOI: 10.1007/s00294-014-0461-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Revised: 10/17/2014] [Accepted: 11/10/2014] [Indexed: 01/12/2023]
Abstract
Pyrenochaeta lycopersici, as other soil-transmitted fungal pathogens, generally received little attention compared to the pathogens affecting the aerial parts of the plants, although causing stunt and important fruit yield reduction of agronomic relevant crops. The scope of this study was to develop a system allowing to investigate the functional role of P. lycopersici genes putatively involved in the corky root rot of tomato. A genetic transformation system based on a split-marker approach was developed and tested to knock out a P. lycopersici gene encoding for a lytic polysaccharide monooxygenase (Plegl1) induced during the disease development. The regions flanking Plegl1 gene were fused with the overlapping parts of hygromycin marker gene, to favour homologous recombination. We were able to obtain four mutants not expressing the Plegl1 gene though, when tested on a susceptible tomato cultivar, Plegl1 mutants showed unaltered virulence, compared with the wild-type strain. The strategy illustrated in the present work demonstrated for the first time that homologous recombination occurs in P. lycopersici. Moreover, a transformation system mediated by Agrobacterium tumefaciens was established and stable genetic transformants have been obtained. The transformation systems developed represent important tools for investigating both the role of genes putatively involved in P. lycopersici interaction with host plant and the function of other physiological traits which emerged to be genetically expanded from the recent genome sequencing of this fungus.
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Affiliation(s)
- Maria Aragona
- Consiglio per la ricerca e la sperimentazione in agricoltura, Centro di ricerca per la patologia vegetale (Plant Pathology Research Centre), Via C. G. Bertero 22, 00156, Rome, Italy,
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Sørensen LQ, Lysøe E, Larsen JE, Khorsand-Jamal P, Nielsen KF, Frandsen RJN. Genetic transformation of Fusarium avenaceum by Agrobacterium tumefaciens mediated transformation and the development of a USER-Brick vector construction system. BMC Mol Biol 2014; 15:15. [PMID: 25048842 PMCID: PMC4133957 DOI: 10.1186/1471-2199-15-15] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 07/04/2014] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND The plant pathogenic and saprophytic fungus Fusarium avenaceum causes considerable in-field and post-field losses worldwide due to its infections of a wide range of different crops. Despite its significant impact on the profitability of agriculture production and a desire to characterize the infection process at the molecular biological level, no genetic transformation protocol has yet been established for F. avenaceum. In the current study, it is shown that F. avenaceum can be efficiently transformed by Agrobacterium tumefaciens mediated transformation. In addition, an efficient and versatile single step vector construction strategy relying on Uracil Specific Excision Reagent (USER) Fusion cloning, is developed. RESULTS The new vector construction system, termed USER-Brick, is based on a limited number of PCR amplified vector fragments (core USER-Bricks) which are combined with PCR generated fragments from the gene of interest. The system was found to have an assembly efficiency of 97% with up to six DNA fragments, based on the construction of 55 vectors targeting different polyketide synthase (PKS) and PKS associated transcription factor encoding genes in F. avenaceum. Subsequently, the ΔFaPKS3 vector was used for optimizing A. tumefaciens mediated transformation (ATMT) of F. avenaceum with respect to six variables. Acetosyringone concentration, co-culturing time, co-culturing temperature and fungal inoculum were found to significantly impact the transformation frequency. Following optimization, an average of 140 transformants per 106 macroconidia was obtained in experiments aimed at introducing targeted genome modifications. Targeted deletion of FaPKS6 (FA08709.2) in F. avenaceum showed that this gene is essential for biosynthesis of the polyketide/nonribosomal compound fusaristatin A. CONCLUSION The new USER-Brick system is highly versatile by allowing for the reuse of a common set of building blocks to accommodate seven different types of genome modifications. New USER-Bricks with additional functionality can easily be added to the system by future users. The optimized protocol for ATMT of F. avenaceum represents the first reported targeted genome modification by double homologous recombination of this plant pathogen and will allow for future characterization of this fungus. Functional linkage of FaPKS6 to the production of the mycotoxin fusaristatin A serves as a first testimony to this.
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Affiliation(s)
| | | | | | | | | | - Rasmus John Normand Frandsen
- Eukaryotic Molecular Cell Biology Group, Department of Systems Biology, The Technical University of Denmark, Søltofts Plads building 223, DK-2800 Kgs,, Lyngby, Denmark.
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Jernerén F, Oliw EH. The fatty acid 8,11-diol synthase of Aspergillus fumigatus is inhibited by imidazole derivatives and unrelated to PpoB. Lipids 2012; 47:707-17. [PMID: 22544380 DOI: 10.1007/s11745-012-3673-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2012] [Accepted: 04/06/2012] [Indexed: 12/13/2022]
Abstract
(8R)-Hydroperoxy-(9Z,12Z)-octadecadienoic acid (8-HPODE) is formed by aspergilli as an intermediate in biosynthesis of oxylipins with effects on sporulation. 8-HPODE is transformed by separate diol synthases to (5S,8R)-dihydroxy- and (8R,11S)-dihydroxy-(9Z,12Z)-octadecadienoic acids (5,8- and 8,11-DiHODE). The former is formed by the cytochrome P450 (P450) domain of 5,8-linoleate diol synthase (5,8-LDS or PpoA). Our aim was to characterize the 8,11-diol synthase of Aspergillus fumigatus, which is prominent in many strains. The 8,11-diol synthase was soluble and had a larger molecular size (>100 kDa) than most P450. Miconazole, ketoconazole, and 1-benzylimidazole, classical inhibitors of P450, reduced the biosynthesis of 8,11-DiHODE from 8-HPODE (apparent IC(50) values ~0.8, ~5, and ~0.6 μM, respectively), but did not inhibit the biosynthesis of 5,8-DiHODE. Analysis of hydroperoxides of regioisomeric C(18) and C(20) fatty acids showed that the 8,11-diol synthase was specific for certain hydroperoxides with R configuration. The suprafacial hydrogen abstraction and oxygen insertion at C-11 of 8-HPODE was associated with a small deuterium kinetic isotope effect ((H) k (cat)/(D) k (cat) ~1.5), consistent with P450-catalyzed oxidation. The genome of A. fumigatus contains over 70 P450 sequences. The reaction mechanism, size, and solubility of 8,11-diol synthase pointed to PpoB, a homologue of 5,8-LDS, as a possible candidate of this activity. Gene deletion of ppoB of A. fumigatus strains AF:∆ku80 and J272 did not inhibit biosynthesis of 8,11-DiHODE and recombinant PpoB appeared to lack diol synthase activity. We conclude that 8,11-DiHODE is formed from 8-HPODE by a soluble and substrate-specific 8,11-diol synthase with catalytic characteristics of class III P450.
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Affiliation(s)
- Fredrik Jernerén
- Department of Pharmaceutical Biosciences, Uppsala Biomedical Center, Uppsala University, 75124, Uppsala, Sweden
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