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Qin H, Yin W, Luo C, Liu L. The Identification, Characterization, and Functional Analysis of the Sugar Transporter Gene Family of the Rice False Smut Pathogen, Villosiclava virens. Int J Mol Sci 2024; 25:600. [PMID: 38203770 PMCID: PMC10779207 DOI: 10.3390/ijms25010600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 12/21/2023] [Accepted: 12/21/2023] [Indexed: 01/12/2024] Open
Abstract
False smut, caused by Villosiclava virens, is becoming increasingly serious in modern rice production systems, leading to yield losses and quality declines. Successful infection requires efficient acquisition of sucrose, abundant in rice panicles, as well as other sugars. Sugar transporters (STPs) may play an important role in this process. STPs belong to a major facilitator superfamily, which consists of large multigenic families necessary to partition sugars between fungal pathogens and their hosts. This study identified and characterized the STP family of V. viren, and further analyzed their gene functions to uncover their roles in interactions with rice. Through genome-wide and systematic bioinformatics analyses, 35 STPs were identified from V.virens and named from VvSTP1 to VvSTP35. Transmembrane domains, gene structures, and conserved motifs of VvSTPs have been identified and characterized through the bioinformatic analysis. In addition, a phylogenetic analysis revealed relationship between VvSTPs and STPs from the other three reference fungi. According to a qRT-PCR and RNA-sequencing analysis, VvSTP expression responded differently to different sole carbon sources and H2O2 treatments, and changed during the pathogenic process, suggesting that these proteins are involved in interactions with rice and potentially functional in pathogenesis. In total, 12 representative VvSTPs were knocked out through genetic recombination in order to analyze their roles in pathogenicity of V. virens. The knock-out mutants of VvSTPs showed little difference in mycelia growth and conidiation, indicating a single gene in this family cannot influence vegetative growth of V. virens. It is clear, however, that these mutants result in a change in infection efficiency in a different way, indicating that VvSTPs play an important role in the pathogenicity of virens. This study is expected to contribute to a better understanding of how host-derived sugars contribute to V. virens pathogenicity.
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Affiliation(s)
- Huimin Qin
- State Key Laboratory of Rice Biology and Breeding, China National Rice Research Institute, Hangzhou 311400, China;
| | - Weixiao Yin
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China;
| | - Chaoxi Luo
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China;
| | - Lianmeng Liu
- State Key Laboratory of Rice Biology and Breeding, China National Rice Research Institute, Hangzhou 311400, China;
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Erdmann EA, Nitsche S, Gorbushina AA, Schumacher J. Genetic Engineering of the Rock Inhabitant Knufia petricola Provides Insight Into the Biology of Extremotolerant Black Fungi. FRONTIERS IN FUNGAL BIOLOGY 2022; 3:862429. [PMID: 37746170 PMCID: PMC10512386 DOI: 10.3389/ffunb.2022.862429] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 03/02/2022] [Indexed: 09/26/2023]
Abstract
Black microcolonial fungi (Ascomycetes from Arthonio-, Dothideo-, and Eurotiomycetes) are stress-tolerant and persistent dwellers of natural and anthropogenic extreme habitats. They exhibit slow yeast-like or meristematic growth, do not form specialized reproduction structures and accumulate the black pigment 1,8-dihydroxynaphthalene (DHN) melanin in the multilayered cell walls. To understand how black fungi live, survive, colonize mineral substrates, and interact with phototrophs genetic methods are needed to test these functions and interactions. We chose the rock inhabitant Knufia petricola of the Chaetothyriales as a model for developing methods for genetic manipulation. Here, we report on the expansion of the genetic toolkit by more efficient multiplex CRISPR/Cas9 using a plasmid-based system for expression of Cas9 and multiple sgRNAs and the implementation of the three resistance selection markers genR (geneticin/nptII), baR (glufosinate/bar), and suR (chlorimuron ethyl/sur). The targeted integration of expression constructs by replacement of essential genes for pigment synthesis allows for an additional color screening of the transformants. The black-pink screening due to the elimination of pks1 (melanin) was applied for promoter studies using GFP fluorescence as reporter. The black-white screening due to the concurrent elimination of pks1 and phs1 (carotenoids) allows to identify transformants that contain the two expression constructs for co-localization or bimolecular fluorescence complementation (BiFC) studies. The co-localization and interaction of the two K. petricola White Collar orthologs were demonstrated. Two intergenic regions (igr1, igr2) were identified in which expression constructs can be inserted without causing obvious phenotypes. Plasmids of the pNXR-XXX series and new compatible entry plasmids were used for fast and easy generation of expression constructs and are suitable for a broad implementation in other fungi. This variety of genetic tools is opening a completely new perspective for mechanistic and very detailed study of expression, functioning and regulation of the genes/proteins encoded by the genomes of black fungi.
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Affiliation(s)
- Eileen A. Erdmann
- Department of Materials and the Environment, Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany
- Department of Biology Chemistry Pharmacy, Freie Universität Berlin, Berlin, Germany
| | - Sarah Nitsche
- Department of Materials and the Environment, Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany
- Department of Biology Chemistry Pharmacy, Freie Universität Berlin, Berlin, Germany
| | - Anna A. Gorbushina
- Department of Materials and the Environment, Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany
- Department of Biology Chemistry Pharmacy, Freie Universität Berlin, Berlin, Germany
- Department of Earth Sciences, Freie Universität Berlin, Berlin, Germany
| | - Julia Schumacher
- Department of Materials and the Environment, Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany
- Department of Biology Chemistry Pharmacy, Freie Universität Berlin, Berlin, Germany
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Li T, Su X, Qu H, Duan X, Jiang Y. Biosynthesis, regulation, and biological significance of fumonisins in fungi: current status and prospects. Crit Rev Microbiol 2021; 48:450-462. [PMID: 34550845 DOI: 10.1080/1040841x.2021.1979465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Fumonisins are one of the most important mycotoxin classes due to their widespread occurrence and potential health threat to humans and animals. Currently, most of the research focuses on the control of fumonisin contamination in the food supply chain. In recent years, significant progress in biochemistry, enzymology, and genetic regulation of fumonisin biosynthesis has been achieved using molecular technology. Furthermore, new insights into the roles of fumonisins in the interaction between fungi and plant hosts have been reported. This review provides an overview of the current understanding of the biosynthesis and regulation of fumonisins. The ecological significance of fumonisins to Fusarium species that produce the toxins is discussed, and the complex regulatory networks of fumonisin synthesis is proposed.
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Affiliation(s)
- Taotao Li
- Key Laboratory of Plant Resource Conservation and Sustainable Utilization, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Xinguo Su
- Tropical Agriculture and Forestry Department, Guangdong AIB Polytechnic College, Guangzhou, China
| | - Hongxia Qu
- Key Laboratory of Plant Resource Conservation and Sustainable Utilization, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Xuewu Duan
- Key Laboratory of Plant Resource Conservation and Sustainable Utilization, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Yueming Jiang
- Key Laboratory of Plant Resource Conservation and Sustainable Utilization, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China.,College of Life Sciences, Gannan Normal University, Ganzhou, China
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4
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N D, Achar PN, Sreenivasa MY. Current Perspectives of Biocontrol Agents for Management of Fusarium verticillioides and Its Fumonisin in Cereals-A Review. J Fungi (Basel) 2021; 7:776. [PMID: 34575814 PMCID: PMC8465378 DOI: 10.3390/jof7090776] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 09/15/2021] [Accepted: 09/17/2021] [Indexed: 11/27/2022] Open
Abstract
Fusarium verticillioides is the most predominant fungal phytopathogen of cereals and it is posing great concern from a global perspective. The fungus is mainly associated with maize, rice, sorghum, wheat, sugarcane, banana, and asparagus and causes cob, stalk, ear, root, crown, top, and foot rot. F. verticillioides produces fumonisins as the major secondary metabolite along with trace levels of beauvericin, fusaric acid, fusarin C, gibberiliformin, and moniliformin. Being a potential carcinogen, fumonisins continue to receive major attention as they are common contaminants in cereals and its processed food products. The importance of elimination of F. verticillioides growth and its associated fumonisin from cereals cannot be overemphasized considering the significant health hazards associated with its consumption. Physical and chemical approaches have been shown to reduce fumonisin B1 concentrations among feeds and food products but have proved to be ineffective during the production process. Hence, biological control methods using microorganisms, plant extracts, antioxidants, essential oils, phenolic compounds, and other advanced technologies such as growing disease-resistant crops by applying genetic engineering, have become an effective alternative for managing F. verticillioides and its toxin. The different methods, challenges, and concerns regarding the biocontrol of F. verticillioides and production of fumonisin B1 have been addressed in the present review.
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Affiliation(s)
- Deepa N
- Department of Studies in Microbiology, University of Mysore, Mysuru 570 006, Karnataka, India;
| | - Premila N. Achar
- Department of Molecular and Cellular Biology, Kennesaw State University, Kennesaw, GA 30144, USA
| | - Marikunte Y. Sreenivasa
- Department of Studies in Microbiology, University of Mysore, Mysuru 570 006, Karnataka, India;
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Achimón F, Krapacher CR, Jacquat AG, Pizzolitto RP, Zygadlo JA. Carbon sources to enhance the biosynthesis of useful secondary metabolites in Fusarium verticillioides submerged cultures. World J Microbiol Biotechnol 2021; 37:78. [PMID: 33797632 DOI: 10.1007/s11274-021-03044-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 03/24/2021] [Indexed: 12/13/2022]
Abstract
Fusarium verticillioides is a prolific producer of useful secondary metabolites such as naphthoquinone pigments, monoterpenes, and sesquiterpenes, as well as the harmful mycotoxins fumonisins. A strategy to increase their production includes creating a proper nutritional environment that enables the fungus to produce the compounds of interest. The aim of the present work was to study the effect of different carbon sources (glucose, fructose, xylose, sucrose, and lactose) on secondary metabolites biosynthesis in F. verticillioides submerged cultures. The production of volatile terpenes was evaluated through gas chromatography coupled to mass spectrometry. The quantification and identification of pigments was conducted using a UV/VIS spectrophotometer and NMR spectrometer, respectively. The quantification of fumonisin B1 and fumonisin B2 was performed by high-performance liquid chromatography. Our results showed that the biosynthesis of naphthoquinone pigments, monoterpenes, and sesquiterpenes was highest in cultures with fructose (13.00 ± 0.71 mmol/g), lactose [564.52 × 10-11 ± 11.50 × 10-11 μg/g dry weight (DW)], and xylose (54.41 × 10-11 ± 1.55 × 10-11 μg/g DW), respectively, with fumonisin being absent or present in trace amounts in the presence of these carbon sources. The highest biosynthesis of fumonisins occurred in sucrose-containing medium (fumonisin B1: 7.85 × 103 ± 0.25 × 103 μg/g DW and fumonisin B2: 0.38 × 103 ± 0.03 × 103 μg/g DW). These results are encouraging since we were able to enhance the production of useful fungal metabolites without co-production with harmful mycotoxins by controlling the carbon source provided in the culture medium.
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Affiliation(s)
- Fernanda Achimón
- Instituto Multidisciplinario de Biología Vegetal (IMBIV-CONICET), Universidad Nacional de Córdoba, Avenida Vélez Sarsfield 1611, X5016 GCA, Córdoba, Argentina.,Instituto de Ciencia y Tecnología de los Alimentos (ICTA), Avenida Vélez Sarsfield 1611, X5016 GCA, Córdoba, Argentina
| | - Claudio R Krapacher
- Instituto Multidisciplinario de Biología Vegetal (IMBIV-CONICET), Universidad Nacional de Córdoba, Avenida Vélez Sarsfield 1611, X5016 GCA, Córdoba, Argentina.,Instituto de Ciencia y Tecnología de los Alimentos (ICTA), Avenida Vélez Sarsfield 1611, X5016 GCA, Córdoba, Argentina
| | - Andrés G Jacquat
- Instituto Multidisciplinario de Biología Vegetal (IMBIV-CONICET), Universidad Nacional de Córdoba, Avenida Vélez Sarsfield 1611, X5016 GCA, Córdoba, Argentina.,Instituto de Ciencia y Tecnología de los Alimentos (ICTA), Avenida Vélez Sarsfield 1611, X5016 GCA, Córdoba, Argentina
| | - Romina P Pizzolitto
- Instituto Multidisciplinario de Biología Vegetal (IMBIV-CONICET), Universidad Nacional de Córdoba, Avenida Vélez Sarsfield 1611, X5016 GCA, Córdoba, Argentina. .,Instituto de Ciencia y Tecnología de los Alimentos (ICTA), Avenida Vélez Sarsfield 1611, X5016 GCA, Córdoba, Argentina.
| | - Julio A Zygadlo
- Instituto Multidisciplinario de Biología Vegetal (IMBIV-CONICET), Universidad Nacional de Córdoba, Avenida Vélez Sarsfield 1611, X5016 GCA, Córdoba, Argentina.,Instituto de Ciencia y Tecnología de los Alimentos (ICTA), Avenida Vélez Sarsfield 1611, X5016 GCA, Córdoba, Argentina
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6
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Achimón F, Dambolena JS, Zygadlo JA, Pizzolitto RP. Carbon sources as factors affecting the secondary metabolism of the maize pathogen Fusarium verticillioides. Lebensm Wiss Technol 2019. [DOI: 10.1016/j.lwt.2019.108470] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Wu Y, Li T, Gong L, Wang Y, Jiang Y. Effects of Different Carbon Sources on Fumonisin Production and FUM Gene Expression by Fusarium proliferatum. Toxins (Basel) 2019; 11:toxins11050289. [PMID: 31121925 PMCID: PMC6563204 DOI: 10.3390/toxins11050289] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Revised: 05/09/2019] [Accepted: 05/14/2019] [Indexed: 01/20/2023] Open
Abstract
Fusarium proliferatum can infect many crops and then produce fumonisins that are very harmful to humans and animals. Previous study indicates that carbon sources play important roles in regulating the fumonisin biosynthesis. Unfortunately, there is limited information on the effects of carbon starvation in comparison with the carbon sources present in the host of fumonisin production in F. proliferatum. Our results indicated that F. proliferatum cultivated in the Czapek's broth (CB) medium in the absence of sucrose could greatly induce production of fumonisin, while an additional supplementation of sucrose to the culture medium significantly reduced the fumonisin production. Furthermore, cellulose and hemicellulose, and polysaccharide extracted from banana peel, which replaced sucrose as the carbon source, can reduce the production of fumonisin by F. proliferatum. Further work showed that these genes related to the synthesis of fumonisin, such as FUM1 and FUM8, were significantly up-regulated in the culture medium in the absence of sucrose. Consistent with fumonisin production, the expressions of FUM gene cluster and ZFR1 gene decreased after the addition of sucrose. Moreover, these genes were also significantly down-regulated in the presence of cellulose, hemicellulose or polysaccharide extracted from peel. Altogether, our results suggested that fumonisin production was regulated in F. proliferatum in response to different carbon source conditions, and this regulation might be mainly via the transcriptional level. Future work on these expressions of the fumonisin biosynthesis-related genes is needed to further clarify the response under different carbon conditions during the infection of F. proliferatum on banana fruit hosts. The findings in this study will provide a new clue regarding the biological effect of the fumonisin production in response to environmental stress.
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Affiliation(s)
- Yu Wu
- Key Laboratory of Plant Resource Conservation and Sustainable Utilization, Guangdong Provincial Key Laboratory of Applied Botany, Key Laboratory of Post-harvest Handling of Fruits, Ministry of Agriculture, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
- School of Life Sciences, University of Chinese Academy of Sciences, Beijing 100039, China.
| | - Taotao Li
- Key Laboratory of Plant Resource Conservation and Sustainable Utilization, Guangdong Provincial Key Laboratory of Applied Botany, Key Laboratory of Post-harvest Handling of Fruits, Ministry of Agriculture, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
| | - Liang Gong
- Key Laboratory of Plant Resource Conservation and Sustainable Utilization, Guangdong Provincial Key Laboratory of Applied Botany, Key Laboratory of Post-harvest Handling of Fruits, Ministry of Agriculture, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
| | - Yong Wang
- Zhongshan Entry-Exit Inspection and Quarantine Bureau, Zhongshan 528403, China.
| | - Yueming Jiang
- Key Laboratory of Plant Resource Conservation and Sustainable Utilization, Guangdong Provincial Key Laboratory of Applied Botany, Key Laboratory of Post-harvest Handling of Fruits, Ministry of Agriculture, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
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Yun Y, Zhou X, Yang S, Wen Y, You H, Zheng Y, Norvienyeku J, Shim WB, Wang Z. Fusarium oxysporum f. sp. lycopersici C 2H 2 transcription factor FolCzf1 is required for conidiation, fusaric acid production, and early host infection. Curr Genet 2019; 65:773-783. [PMID: 30631890 DOI: 10.1007/s00294-019-00931-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2018] [Revised: 12/21/2018] [Accepted: 01/03/2019] [Indexed: 11/26/2022]
Abstract
The soil-borne, asexual fungus Fusarium oxysporum f.sp. lycopersici (Fol) is a causal agent of tomato wilt disease. The infection process of Fol comprises root recognition, adhesion, penetration, colonization of the root cortex and hyphal proliferation within the xylem vessels, which are under the regulation of virulence-involved transcription factors (TFs). In this study, we identified a gene, designated FolCZF1, which encodes a C2H2 TF in Fol. The homologs of FolCzf1 are also known to affect pathogenicity in F. graminearum and Magnaporthe oryzae on wheat and rice, respectively. We learned that FolCZF1 transcript level is upregulated in conidia and early host infection stage, which led us to hypothesize that FolCzf1 is associated with early host infection in Fol. The FolCZF1 deletion mutant (ΔFolCZF1) exhibited defects in growth rate, conidiation, conidia morphology and a complete loss of virulence on tomato root. Further microscopic observation showed that ΔFolCZF1 can penetrate the root but the primary infection hypha cannot extend its colonization inside the host tissue, suggesting that FolCzf1 TF plays an important role in early infection. Fusaric acid, a secondary metabolite produced by Fusarium species, is suggested as a virulence factor in many crop diseases. We found that FolCzf1 plays a critical role in fusaric acid production by regulating the expression of fusaric acid biosynthesis genes. In summary, FolCzf1 is required for conidiation, secondary metabolism, and early host infection in Fol, and we propose that homologs of FolCzf1 are required for early parasitic growth in other plant pathogenic filamentous fungi.
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Affiliation(s)
- Yingzi Yun
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China.
| | - Xin Zhou
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Shuai Yang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Ya Wen
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Haixia You
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Yuru Zheng
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
- Fujian Institute for Food and Drug Quality Control, Fuzhou, China
| | - Justice Norvienyeku
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Won-Bo Shim
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China.
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX, USA.
| | - Zonghua Wang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China.
- Institute of Oceanography, Minjiang University, Fuzhou, China.
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Gu Q, Ji T, Sun X, Huang H, Zhang H, Lu X, Wu L, Huo R, Wu H, Gao X. Histone H3 lysine 9 methyltransferase FvDim5 regulates fungal development, pathogenicity and osmotic stress responses in Fusarium verticillioides. FEMS Microbiol Lett 2018; 364:4094912. [PMID: 28957455 DOI: 10.1093/femsle/fnx184] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2017] [Accepted: 08/23/2017] [Indexed: 12/30/2022] Open
Abstract
Histone methylation plays important biological roles in eukaryotic cells. Methylation of lysine 9 at histone H3 (H3K9me) is critical for regulating chromatin structure and gene transcription. Dim5 is a lysine histone methyltransferase (KHMTase) enzyme, which is responsible for the methylation of H3K9 in eukaryotes. In the current study, we identified a single ortholog of Neurospora crassa Dim5 in Fusarium verticillioides. In this study, we report that FvDim5 regulates the trimethylation of H3K9 (H3K9me3). The FvDIM5 deletion mutant (ΔFvDim5) showed significant defects in conidiation, perithecium production and fungal virulence. Unexpectedly, we found that deletion of FvDIM5 resulted in increased tolerance to osmotic stresses and upregulated FvHog1 phosphorylation. These results indicate the importance of FvDim5 for the regulation of fungal development, pathogenicity and osmotic stress responses in F. verticillioides.
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Affiliation(s)
- Qin Gu
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Education, Nanjing 210095, China
| | - Tiantian Ji
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Education, Nanjing 210095, China
| | - Xiao Sun
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Education, Nanjing 210095, China
| | - Hai Huang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Education, Nanjing 210095, China
| | - Hao Zhang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Education, Nanjing 210095, China
| | - Xi Lu
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Education, Nanjing 210095, China
| | - Liming Wu
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Education, Nanjing 210095, China
| | - Rong Huo
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Education, Nanjing 210095, China
| | - Huijun Wu
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Education, Nanjing 210095, China
| | - Xuewen Gao
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Education, Nanjing 210095, China
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Blacutt AA, Gold SE, Voss KA, Gao M, Glenn AE. Fusarium verticillioides: Advancements in Understanding the Toxicity, Virulence, and Niche Adaptations of a Model Mycotoxigenic Pathogen of Maize. PHYTOPATHOLOGY 2018; 108:312-326. [PMID: 28971734 DOI: 10.1094/phyto-06-17-0203-rvw] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The importance of understanding the biology of the mycotoxigenic fungus Fusarium verticillioides and its various microbial and plant host interactions is critical given its threat to maize, one of the world's most valuable food crops. Disease outbreaks and mycotoxin contamination of grain threaten economic returns and have grave implications for human and animal health and food security. Furthermore, F. verticillioides is a member of a genus of significant phytopathogens and, thus, data regarding its host association, biosynthesis of secondary metabolites, and other metabolic (degradative) capabilities are consequential to both basic and applied research efforts across multiple pathosystems. Notorious among its secondary metabolites are the fumonisin mycotoxins, which cause severe animal diseases and are implicated in human disease. Additionally, studies of these mycotoxins have led to new understandings of F. verticillioides plant pathogenicity and provide tools for research into cellular processes and host-pathogen interaction strategies. This review presents current knowledge regarding several significant lines of F. verticillioides research, including facets of toxin production, virulence, and novel fitness strategies exhibited by this fungus across rhizosphere and plant environments.
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Affiliation(s)
- Alex A Blacutt
- First and fourth authors: Department of Plant Pathology, University of Georgia, Athens 30602; and second, third, and fifth authors: United States Department of Agriculture-Agricultural Research Service, U.S. National Poultry Research Center, Toxicology and Mycotoxin Research Unit, Athens, GA 30605-2720
| | - Scott E Gold
- First and fourth authors: Department of Plant Pathology, University of Georgia, Athens 30602; and second, third, and fifth authors: United States Department of Agriculture-Agricultural Research Service, U.S. National Poultry Research Center, Toxicology and Mycotoxin Research Unit, Athens, GA 30605-2720
| | - Kenneth A Voss
- First and fourth authors: Department of Plant Pathology, University of Georgia, Athens 30602; and second, third, and fifth authors: United States Department of Agriculture-Agricultural Research Service, U.S. National Poultry Research Center, Toxicology and Mycotoxin Research Unit, Athens, GA 30605-2720
| | - Minglu Gao
- First and fourth authors: Department of Plant Pathology, University of Georgia, Athens 30602; and second, third, and fifth authors: United States Department of Agriculture-Agricultural Research Service, U.S. National Poultry Research Center, Toxicology and Mycotoxin Research Unit, Athens, GA 30605-2720
| | - Anthony E Glenn
- First and fourth authors: Department of Plant Pathology, University of Georgia, Athens 30602; and second, third, and fifth authors: United States Department of Agriculture-Agricultural Research Service, U.S. National Poultry Research Center, Toxicology and Mycotoxin Research Unit, Athens, GA 30605-2720
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Zaccaron AZ, Woloshuk CP, Bluhm BH. Comparative genomics of maize ear rot pathogens reveals expansion of carbohydrate-active enzymes and secondary metabolism backbone genes in Stenocarpella maydis. Fungal Biol 2017; 121:966-983. [PMID: 29029703 DOI: 10.1016/j.funbio.2017.08.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Revised: 08/15/2017] [Accepted: 08/18/2017] [Indexed: 12/11/2022]
Abstract
Stenocarpella maydis is a plant pathogenic fungus that causes Diplodia ear rot, one of the most destructive diseases of maize. To date, little information is available regarding the molecular basis of pathogenesis in this organism, in part due to limited genomic resources. In this study, a 54.8 Mb draft genome assembly of S. maydis was obtained with Illumina and PacBio sequencing technologies, and analyzed. Comparative genomic analyses with the predominant maize ear rot pathogens Aspergillus flavus, Fusarium verticillioides, and Fusarium graminearum revealed an expanded set of carbohydrate-active enzymes for cellulose and hemicellulose degradation in S. maydis. Analyses of predicted genes involved in starch degradation revealed six putative α-amylases, four extracellular and two intracellular, and two putative γ-amylases, one of which appears to have been acquired from bacteria via horizontal transfer. Additionally, 87 backbone genes involved in secondary metabolism were identified, which represents one of the largest known assemblages among Pezizomycotina species. Numerous secondary metabolite gene clusters were identified, including two clusters likely involved in the biosynthesis of diplodiatoxin and chaetoglobosins. The draft genome of S. maydis presented here will serve as a useful resource for molecular genetics, functional genomics, and analyses of population diversity in this organism.
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Affiliation(s)
- Alex Z Zaccaron
- Department of Plant Pathology, University of Arkansas, Division of Agriculture, Fayetteville, AR 72701, USA
| | - Charles P Woloshuk
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, USA
| | - Burton H Bluhm
- Department of Plant Pathology, University of Arkansas, Division of Agriculture, Fayetteville, AR 72701, USA.
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12
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Niehaus EM, Studt L, von Bargen KW, Kummer W, Humpf HU, Reuter G, Tudzynski B. Sound of silence: the beauvericin cluster in Fusarium fujikuroi is controlled by cluster-specific and global regulators mediated by H3K27 modification. Environ Microbiol 2017; 18:4282-4302. [PMID: 27750383 DOI: 10.1111/1462-2920.13576] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 10/11/2016] [Indexed: 01/25/2023]
Abstract
In this study, we compared the secondary metabolite profile of Fusarium fujikuroi and the histone deacetylase mutant ΔHDA1. We identified a novel peak in ΔHDA1, which was identified as beauvericin (BEA). Going in line with a 1000-fold increased BEA production, the respective non-ribosomal peptide synthetase (NRPS)-encoding gene (BEA1), as well as two adjacent genes (BEA2-BEA3), were significantly up-regulated in ΔHDA1 compared to the wild type. A special role was revealed for the ABC transporter Bea3: deletion of the encoding gene resulted in significant up-regulation of BEA1 and BEA2 and drastically elevated product yields. Furthermore, mutation of a conserved sequence motif in the promoter of BEA1 released BEA repression and resulted in elevated product levels. Candidate transcription factors (TFs) that could bind to this motif are the cluster-specific TF Bea4 as well as a homolog of the global mammalian Kruppel-like TF Yin Yang 1 (Yy1), both acting as repressors of BEA biosynthesis. In addition to Hda1, BEA biosynthesis is repressed by the activity of the H3K27 methyltransferase Kmt6. Consistently, Western blot analyses revealed a genome-wide enrichment of H3K27 acetylation (H3K27ac) in the ΔHDA1 and KMT6 knock-down mutants. Subsequent chromatin immunoprecipitation (ChIP) experiments showed elevated H3K27ac modification levels at the BEA cluster.
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Affiliation(s)
- Eva-Maria Niehaus
- Institut für Biologie und Biotechnologie der Pflanzen, Westfälische Wilhelms-Universität Münster, Schlossplatz 8, Münster, D-48143
| | - Lena Studt
- Institut für Biologie und Biotechnologie der Pflanzen, Westfälische Wilhelms-Universität Münster, Schlossplatz 8, Münster, D-48143
| | - Katharina W von Bargen
- Institut für Lebensmittelchemie, Westfälische Wilhelms-Universität Münster, Corrensstr. 45, Münster, D-48149
| | - Wiebke Kummer
- Institut für Genetik, Martin Luther Universität Halle-Wittenberg, Weinbergweg 10, Halle (Saale), D-06120
| | - Hans-Ulrich Humpf
- Institut für Lebensmittelchemie, Westfälische Wilhelms-Universität Münster, Corrensstr. 45, Münster, D-48149
| | - Gunter Reuter
- Institut für Genetik, Martin Luther Universität Halle-Wittenberg, Weinbergweg 10, Halle (Saale), D-06120
| | - Bettina Tudzynski
- Institut für Biologie und Biotechnologie der Pflanzen, Westfälische Wilhelms-Universität Münster, Schlossplatz 8, Münster, D-48143
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13
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Niu C, Payne GA, Woloshuk CP. Involvement of FST1 from Fusarium verticillioides in virulence and transport of inositol. MOLECULAR PLANT PATHOLOGY 2017; 18:695-707. [PMID: 27195938 PMCID: PMC6638204 DOI: 10.1111/mpp.12430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 05/11/2016] [Accepted: 05/13/2016] [Indexed: 06/05/2023]
Abstract
Fumonisin B1 (FB1), a polyketide mycotoxin produced by Fusarium verticillioides during the colonization of maize kernels, is detrimental to human and animal health. FST1 encodes a putative protein with 12 transmembrane domains; however, its function remains unknown. The FST1 gene is highly expressed by the fungus in the endosperm of maize kernels compared with the levels of expression in germ tissues. Previous research has shown that FST1 affects FB1 production, virulence, hydrogen peroxide resistance, hydrophobicity and macroconidia production. Here, we examine the phylogeny of FST1, its expression in a Saccharomyces cerevisiae strain lacking a functional myo-inositol transporter (ITR1) and the effect of amino acid changes in the central loop and C-terminus regions of FST1 on functionality. The results indicate that expression of FST1 in an ITR1 mutant strain restores growth on myo-inositol medium to wild-type levels and restores the inhibitory effects of FB1, suggesting that FST1 can transport both myo-inositol and FB1 into yeast cells. Our results with engineered FST1 also indicate that amino acids in the central loop and C-terminus regions are important for FST1 functionality in both S. cerevisiae and F. verticillioides. Overall, this research has established the first characterized inositol transporter in filamentous fungi and has advanced our knowledge about the global regulatory functions of FST1.
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Affiliation(s)
- Chenxing Niu
- Department of Botany and Plant PathologyPurdue UniversityWest LafayetteIN47907‐2054USA
| | - Gary A. Payne
- Department of Plant PathologyNorth Carolina State UniversityRaleighNC27695‐7567USA
| | - Charles P. Woloshuk
- Department of Botany and Plant PathologyPurdue UniversityWest LafayetteIN47907‐2054USA
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14
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Ridenour JB, Bluhm BH. The novel fungal-specific gene FUG1 has a role in pathogenicity and fumonisin biosynthesis in Fusarium verticillioides. MOLECULAR PLANT PATHOLOGY 2017; 18:513-528. [PMID: 27071505 PMCID: PMC6638258 DOI: 10.1111/mpp.12414] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2016] [Revised: 04/06/2016] [Accepted: 04/07/2016] [Indexed: 05/05/2023]
Abstract
Fusarium verticillioides is a globally important pathogen of maize, capable of causing severe yield reductions and economic losses. In addition, F. verticillioides produces toxic secondary metabolites during kernel colonization that pose significant threats to human and animal health. Fusarium verticillioides and other plant-pathogenic fungi possess a large number of genes with no known or predicted function, some of which could encode novel virulence factors or antifungal targets. In this study, we identified and characterized the novel gene FUG1 (Fungal Unknown Gene 1) in F. verticillioides through functional genetics. Deletion of FUG1 impaired maize kernel colonization and fumonisin biosynthesis. In addition, deletion of FUG1 increased sensitivity to the antimicrobial compound 2-benzoxazolinone and to hydrogen peroxide, which indicates that FUG1 may play a role in mitigating stresses associated with host defence. Transcriptional profiling via RNA-sequencing (RNA-seq) identified numerous fungal genes that were differentially expressed in the kernel environment following the deletion of FUG1, including genes involved in secondary metabolism and mycelial development. Sequence analysis of the Fug1 protein provided evidence for nuclear localization, DNA binding and a domain of unknown function associated with previously characterized transcriptional regulators. This information, combined with the observed transcriptional reprogramming in the deletion mutant, suggests that FUG1 represents a novel class of fungal transcription factors or genes otherwise involved in signal transduction.
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Affiliation(s)
- John B. Ridenour
- Department of Plant PathologyUniversity of Arkansas Division of AgricultureFayettevilleAR 72701USA
| | - Burton H. Bluhm
- Department of Plant PathologyUniversity of Arkansas Division of AgricultureFayettevilleAR 72701USA
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15
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Studt L, Janevska S, Arndt B, Boedi S, Sulyok M, Humpf HU, Tudzynski B, Strauss J. Lack of the COMPASS Component Ccl1 Reduces H3K4 Trimethylation Levels and Affects Transcription of Secondary Metabolite Genes in Two Plant-Pathogenic Fusarium Species. Front Microbiol 2017; 7:2144. [PMID: 28119673 PMCID: PMC5220078 DOI: 10.3389/fmicb.2016.02144] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 12/20/2016] [Indexed: 01/07/2023] Open
Abstract
In the two fungal pathogens Fusarium fujikuroi and Fusarium graminearum, secondary metabolites (SMs) are fitness and virulence factors and there is compelling evidence that the coordination of SM gene expression is under epigenetic control. Here, we characterized Ccl1, a subunit of the COMPASS complex responsible for methylating lysine 4 of histone H3 (H3K4me). We show that Ccl1 is not essential for viability but a regulator of genome-wide trimethylation of H3K4 (H3K4me3). Although, recent work in Fusarium and Aspergillus spp. detected only sporadic H3K4 methylation at the majority of the SM gene clusters, we show here that SM profiles in CCL1 deletion mutants are strongly deviating from the wild type. Cross-complementation experiments indicate high functional conservation of Ccl1 as phenotypes of the respective △ccl1 were rescued in both fungi. Strikingly, biosynthesis of the species-specific virulence factors gibberellic acid and deoxynivalenol produced by F. fujikuroi and F. graminearum, respectively, was reduced in axenic cultures but virulence was not attenuated in these mutants, a phenotype which goes in line with restored virulence factor production levels in planta. This suggests that yet unknown plant-derived signals are able to compensate for Ccl1 function during pathogenesis.
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Affiliation(s)
- Lena Studt
- Division of Microbial Genetics and Pathogen Interactions, Department of Applied Genetics and Cell Biology, BOKU-University of Natural Resources and Life SciencesVienna, Tulln an der Donau, Austria,Institute for Plant Biology and Biotechnology, Westfälische Wilhelms UniversityMünster, Germany,*Correspondence: Lena Studt, Joseph Strauss,
| | - Slavica Janevska
- Institute for Plant Biology and Biotechnology, Westfälische Wilhelms UniversityMünster, Germany
| | - Birgit Arndt
- Institute of Food Chemistry, Westfälische Wilhelms UniversityMünster, Germany
| | - Stefan Boedi
- Division of Microbial Genetics and Pathogen Interactions, Department of Applied Genetics and Cell Biology, BOKU-University of Natural Resources and Life SciencesVienna, Tulln an der Donau, Austria
| | - Michael Sulyok
- Center for Analytical Chemistry, Department IFA-Tulln, BOKU-University of Natural Resources and Life SciencesVienna, Tulln an der Donau, Austria
| | - Hans-Ulrich Humpf
- Institute of Food Chemistry, Westfälische Wilhelms UniversityMünster, Germany
| | - Bettina Tudzynski
- Institute for Plant Biology and Biotechnology, Westfälische Wilhelms UniversityMünster, Germany
| | - Joseph Strauss
- Division of Microbial Genetics and Pathogen Interactions, Department of Applied Genetics and Cell Biology, BOKU-University of Natural Resources and Life SciencesVienna, Tulln an der Donau, Austria,*Correspondence: Lena Studt, Joseph Strauss,
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16
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Shu X, Livingston DP, Woloshuk CP, Payne GA. Comparative Histological and Transcriptional Analysis of Maize Kernels Infected with Aspergillus flavus and Fusarium verticillioides. FRONTIERS IN PLANT SCIENCE 2017; 8:2075. [PMID: 29270183 PMCID: PMC5723656 DOI: 10.3389/fpls.2017.02075] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 11/20/2017] [Indexed: 05/04/2023]
Abstract
Aspergillus flavus and Fusarium verticillioides infect maize kernels and contaminate them with the mycotoxins aflatoxin, and fumonisin, respectively. Genetic resistance in maize to these fungi and to mycotoxin contamination has been difficult to achieve due to lack of identified resistance genes. The objective of this study was to identify new candidate resistance genes by characterizing their temporal expression in response to infection and comparing expression of these genes with genes known to be associated with plant defense. Fungal colonization and transcriptional changes in kernels inoculated with each fungus were monitored at 4, 12, 24, 48, and 72 h post inoculation (hpi). Maize kernels responded by differential gene expression to each fungus within 4 hpi, before the fungi could be observed visually, but more genes were differentially expressed between 48 and 72 hpi, when fungal colonization was more extensive. Two-way hierarchal clustering analysis grouped the temporal expression profiles of the 5,863 differentially expressed maize genes over all time points into 12 clusters. Many clusters were enriched for genes previously associated with defense responses to either A. flavus or F. verticillioides. Also within these expression clusters were genes that lacked either annotation or assignment to functional categories. This study provided a comprehensive analysis of gene expression of each A. flavus and F. verticillioides during infection of maize kernels, it identified genes expressed early and late in the infection process, and it provided a grouping of genes of unknown function with similarly expressed defense related genes that could inform selection of new genes as targets in breeding strategies.
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Affiliation(s)
- Xiaomei Shu
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC, United States
| | - David P. Livingston
- Department of Crop Science, North Carolina State University, Raleigh, NC, United States
| | - Charles P. Woloshuk
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, United States
| | - Gary A. Payne
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC, United States
- *Correspondence: Gary A. Payne, ;
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17
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Studt L, Rösler SM, Burkhardt I, Arndt B, Freitag M, Humpf HU, Dickschat JS, Tudzynski B. Knock-down of the methyltransferase Kmt6 relieves H3K27me3 and results in induction of cryptic and otherwise silent secondary metabolite gene clusters in Fusarium fujikuroi. Environ Microbiol 2016; 18:4037-4054. [PMID: 27348741 PMCID: PMC5118082 DOI: 10.1111/1462-2920.13427] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 06/19/2016] [Indexed: 01/07/2023]
Abstract
Filamentous fungi produce a vast array of secondary metabolites (SMs) and some play a role in agriculture or pharmacology. Sequencing of the rice pathogen Fusarium fujikuroi revealed the presence of far more SM-encoding genes than known products. SM production is energy-consuming and thus tightly regulated, leaving the majority of SM gene clusters silent under laboratory conditions. One important regulatory layer in SM biosynthesis involves histone modifications that render the underlying genes either silent or poised for transcription. Here, we show that the majority of the putative SM gene clusters in F. fujikuroi are located within facultative heterochromatin marked by trimethylated lysine 27 on histone 3 (H3K27me3). Kmt6, the methyltransferase responsible for establishing this histone mark, appears to be essential in this fungus, and knock-down of Kmt6 in the KMT6kd strain shows a drastic phenotype affecting fungal growth and development. Transcription of four so far cryptic and otherwise silent putative SM gene clusters was induced in the KMT6kd strain, in which decreased expression of KMT6 is accompanied by reduced H3K27me3 levels at the respective gene loci and accumulation of novel metabolites. One of the four putative SM gene clusters, named STC5, was analysed in more detail thereby revealing a novel sesquiterpene.
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Affiliation(s)
- Lena Studt
- Institute of Plant Biology and Biotechnology, Westfälische Wilhelms-University Münster, 48143 Münster, Germany,Corresponding author: L. Studt, Division of Microbial Genetics and Pathogen Interaction, Department of Applied Genetics and Cell Biology, Campus-Tulln, BOKU-University of Natural Resources and Life Science, Vienna, Austria, , phone: (+43) 1 / 47654-6722
| | - Sarah M. Rösler
- Institute of Plant Biology and Biotechnology, Westfälische Wilhelms-University Münster, 48143 Münster, Germany,Institute of Food Chemistry, Westfälische Wilhelms-University Münster, 48149 Münster, Germany
| | - Immo Burkhardt
- Kekulé Institute for Organic Chemistry and Biochemistry, Rheinische Friedrich-Wilhelms-University Bonn, 53121 Bonn, Germany
| | - Birgit Arndt
- Institute of Food Chemistry, Westfälische Wilhelms-University Münster, 48149 Münster, Germany
| | - Michael Freitag
- Department of Biochemistry and Biophysics, Center for Genome Research and Biocomputing, Oregon State University, Corvallis, 97331 Oregon, United States of America
| | - Hans-Ulrich Humpf
- Institute of Food Chemistry, Westfälische Wilhelms-University Münster, 48149 Münster, Germany
| | - Jeroen S. Dickschat
- Kekulé Institute for Organic Chemistry and Biochemistry, Rheinische Friedrich-Wilhelms-University Bonn, 53121 Bonn, Germany
| | - Bettina Tudzynski
- Institute of Plant Biology and Biotechnology, Westfälische Wilhelms-University Münster, 48143 Münster, Germany
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18
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Ridenour JB, Smith JE, Bluhm BH. The HAP Complex Governs Fumonisin Biosynthesis and Maize Kernel Pathogenesis in Fusarium verticillioides. J Food Prot 2016; 79:1498-1507. [PMID: 28221941 DOI: 10.4315/0362-028x.jfp-15-596] [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] [Indexed: 11/11/2022]
Abstract
Contamination of maize ( Zea mays ) with fumonisins produced by the fungus Fusarium verticillioides is a global concern for food safety. Fumonisins are a group of polyketide-derived secondary metabolites linked to esophageal cancer and neural tube birth defects in humans and numerous toxicoses in livestock. Despite the importance of fumonisins in global maize production, the regulation of fumonisin biosynthesis during kernel pathogenesis is poorly understood. The HAP complex is a conserved, heterotrimeric transcriptional regulator that binds the consensus sequence CCAAT to modulate gene expression. Recently, functional characterization of the Hap3 subunit linked the HAP complex to the regulation of secondary metabolism and stalk rot pathogenesis in F. verticillioides . Here, we determine the involvement of HAP3 in fumonisin biosynthesis and kernel pathogenesis. Deletion of HAP3 suppressed fumonisin biosynthesis on both nonviable and live maize kernels and impaired pathogenesis in living kernels. Transcriptional profiling via RNA sequencing indicated that the HAP complex regulates at least 1,223 genes in F. verticillioides , representing nearly 10% of all predicted genes. Disruption of the HAP complex caused the misregulation of biosynthetic gene clusters underlying the production of secondary metabolites, including fusarins. Taken together, these results reveal that the HAP complex is a central regulator of fumonisin biosynthesis and kernel pathogenesis and works as both a positive and negative regulator of secondary metabolism in F. verticillioides .
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Affiliation(s)
- John B Ridenour
- Department of Plant Pathology, Division of Agriculture, University of Arkansas, Fayetteville, Arkansas 72701, USA
| | - Jonathon E Smith
- Department of Plant Pathology, Division of Agriculture, University of Arkansas, Fayetteville, Arkansas 72701, USA
| | - Burton H Bluhm
- Department of Plant Pathology, Division of Agriculture, University of Arkansas, Fayetteville, Arkansas 72701, USA
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19
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Oh M, Son H, Choi GJ, Lee C, Kim JC, Kim H, Lee YW. Transcription factor ART1 mediates starch hydrolysis and mycotoxin production in Fusarium graminearum and F. verticillioides. MOLECULAR PLANT PATHOLOGY 2016; 17:755-68. [PMID: 26456718 PMCID: PMC6638531 DOI: 10.1111/mpp.12328] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Molecular mechanisms underlying the responses to environmental factors, such as nitrogen, carbon and pH, involve components that regulate the production of secondary metabolites, including mycotoxins. In this study, we identified and characterized a gene in the FGSG_02083 locus, designated as FgArt1, which was predicted to encode a Zn(II)2 Cys6 zinc finger transcription factor. An FgArt1 deletion mutant of Fusarium graminearum exhibited impaired starch hydrolysis as a result of significantly reduced α-amylase gene expression. The deletion strain was unable to produce trichothecenes and exhibited low Tri5 and Tri6 expression levels, whereas the complemented strain showed a similar ability to produce trichothecenes as the wild-type strain. In addition, FgArt1 deletion resulted in impairment of germination in starch liquid medium and reduced pathogenicity on flowering wheat heads. To investigate the roles of the FgArt1 homologue in F. verticillioides, we deleted the FVEG_02083 gene, and the resulting strain showed defects in starch hydrolysis, similar to the FgArt1 deletion strain, and produced no detectable level of fumonisin B1 . Fum1 and Fum12 expression levels were undetectable in the deletion strain. However, when the FvArt1-deleted F. verticillioides strain was complemented with FgArt1, the resulting strain was unable to recover the production of fumonisin B1 , although FgArt1 expression and starch hydrolysis were induced. Thus, our results suggest that there are different regulatory pathways governed by each ART1 transcription factor in trichothecene and fumonisin biosynthesis. Taken together, we suggest that ART1 plays an important role in both trichothecene and fumonisin biosynthesis by the regulation of genes involved in starch hydrolysis.
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Affiliation(s)
- Mira Oh
- Center for Eco-Friendly New Materials, Korea Research Institute of Chemical Technology, Daejeon, 305-600, South Korea
- Department of Green Chemistry and Environmental Biotechnology, Korea University of Science and Technology, Daejeon, 305-350, South Korea
| | - Hokyoung Son
- Department of Agricultural Biotechnology and Center for Fungal Pathogenesis, Seoul National University, Seoul, 151-921, South Korea
| | - Gyung Ja Choi
- Center for Eco-Friendly New Materials, Korea Research Institute of Chemical Technology, Daejeon, 305-600, South Korea
| | - Chanhui Lee
- Department of Plant and Environmental New Resources, Kyung Hee University, Yongin, 446-701, South Korea
| | - Jin-Cheol Kim
- Division of Applied Bioscience and Biotechnology, Chonnam National University, Gwangju, 500-757, South Korea
| | - Hun Kim
- Center for Eco-Friendly New Materials, Korea Research Institute of Chemical Technology, Daejeon, 305-600, South Korea
- Department of Green Chemistry and Environmental Biotechnology, Korea University of Science and Technology, Daejeon, 305-350, South Korea
| | - Yin-Won Lee
- Department of Agricultural Biotechnology and Center for Fungal Pathogenesis, Seoul National University, Seoul, 151-921, South Korea
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20
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Alberts JF, van Zyl WH, Gelderblom WCA. Biologically Based Methods for Control of Fumonisin-Producing Fusarium Species and Reduction of the Fumonisins. Front Microbiol 2016; 7:548. [PMID: 27199904 PMCID: PMC4845651 DOI: 10.3389/fmicb.2016.00548] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 04/04/2016] [Indexed: 12/03/2022] Open
Abstract
Infection by the fumonisin-producing Fusarium spp. and subsequent fumonisin contamination of maize adversely affect international trade and economy with deleterious effects on human and animal health. In developed countries high standards of the major food suppliers and retailers are upheld and regulatory controls deter the importation and local marketing of fumonisin-contaminated food products. In developing countries regulatory measures are either lacking or poorly enforced, due to food insecurity, resulting in an increased mycotoxin exposure. The lack and poor accessibility of effective and environmentally safe control methods have led to an increased interest in practical and biological alternatives to reduce fumonisin intake. These include the application of natural resources, including plants, microbial cultures, genetic material thereof, or clay minerals pre- and post-harvest. Pre-harvest approaches include breeding for resistant maize cultivars, introduction of biocontrol microorganisms, application of phenolic plant extracts, and expression of antifungal proteins and fumonisin degrading enzymes in transgenic maize cultivars. Post-harvest approaches include the removal of fumonisins by natural clay adsorbents and enzymatic degradation of fumonisins through decarboxylation and deamination by recombinant carboxylesterase and aminotransferase enzymes. Although, the knowledge base on biological control methods has expanded, only a limited number of authorized decontamination products and methods are commercially available. As many studies detailed the use of natural compounds in vitro, concepts in reducing fumonisin contamination should be developed further for application in planta and in the field pre-harvest, post-harvest, and during storage and food-processing. In developed countries an integrated approach, involving good agricultural management practices, hazard analysis and critical control point (HACCP) production, and storage management, together with selected biologically based treatments, mild chemical and physical treatments could reduce fumonisin contamination effectively. In rural subsistence farming communities, simple, practical, and culturally acceptable hand-sorting, maize kernel washing, and dehulling intervention methods proved to be effective as a last line of defense for reducing fumonisin exposure. Biologically based methods for control of fumonisin-producing Fusarium spp. and decontamination of the fumonisins could have potential commercial application, while simple and practical intervention strategies could also impact positively on food safety and security, especially in rural populations reliant on maize as a dietary staple.
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Affiliation(s)
- Johanna F. Alberts
- Mycotoxicology and Chemoprevention Research Group, Institute of Biomedical and Microbial Biotechnology, Cape Peninsula University of TechnologyBellville, South Africa
| | - Willem H. van Zyl
- Microbiology Department, Stellenbosch UniversityStellenbosch, South Africa
| | - Wentzel C. A. Gelderblom
- Mycotoxicology and Chemoprevention Research Group, Institute of Biomedical and Microbial Biotechnology, Cape Peninsula University of TechnologyBellville, South Africa
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21
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Rösler SM, Sieber CMK, Humpf HU, Tudzynski B. Interplay between pathway-specific and global regulation of the fumonisin gene cluster in the rice pathogen Fusarium fujikuroi. Appl Microbiol Biotechnol 2016; 100:5869-82. [PMID: 26966024 DOI: 10.1007/s00253-016-7426-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Revised: 02/17/2016] [Accepted: 02/26/2016] [Indexed: 12/17/2022]
Abstract
The rice pathogenic fungus Fusarium fujikuroi is known to produce a large variety of secondary metabolites. Besides the gibberellins, causing the bakanae effect in infected rice seedlings, the fungus produces several mycotoxins and pigments. Among the 47 putative secondary metabolite gene clusters identified in the genome of F. fujikuroi, the fumonisin gene cluster (FUM) shows very high homology to the FUM cluster of the main fumonisin producer Fusarium verticillioides, a pathogen of maize. Despite the high level of cluster gene conservation, total fumonisin FB1 and FB2 levels (FBx) produced by F. fujikuroi were only 1-10 % compared to F. verticillioides under inducing conditions. Nitrogen repression was found to be relevant for wild-type strains of both species. However, addition of germinated maize kernels activated the FBx production only in F. verticillioides, reflecting the different host specificity of both wild-type strains. Over-expression of the pathway-specific transcription factor Fum21 in F. fujikuroi strongly activated the FUM cluster genes leading to 1000-fold elevated FBx levels. To gain further insights into the nitrogen metabolite repression of FBx biosynthesis, we studied the impact of the global nitrogen regulators AreA and AreB and demonstrated that both GATA-type transcription factors are essential for full activation of the FUM gene cluster. Loss of one of them obstructs the pathway-specific transcription factor Fum21 to fully activate expression of FUM cluster genes.
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Affiliation(s)
- Sarah M Rösler
- Institute of Food Chemistry, Westfälische Wilhelms-Universität Münster, Corrensstraße 45, 48149, Münster, Germany.,Institute of Plant Biology and Biotechnology, Westfälische Wilhelms-Universität Münster, Schlossplatz 8, 48143, Münster, Germany
| | - Christian M K Sieber
- Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Institute of Bioinformatics and Systems Biology, Ingolstädter Landstraße 1, 85764, Neuherberg, Germany.,DOE Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA, 94598, USA
| | - Hans-Ulrich Humpf
- Institute of Food Chemistry, Westfälische Wilhelms-Universität Münster, Corrensstraße 45, 48149, Münster, Germany
| | - Bettina Tudzynski
- Institute of Plant Biology and Biotechnology, Westfälische Wilhelms-Universität Münster, Schlossplatz 8, 48143, Münster, Germany.
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Studt L, Janevska S, Niehaus EM, Burkhardt I, Arndt B, Sieber CMK, Humpf HU, Dickschat JS, Tudzynski B. Two separate key enzymes and two pathway-specific transcription factors are involved in fusaric acid biosynthesis in Fusarium fujikuroi. Environ Microbiol 2016; 18:936-56. [PMID: 26662839 DOI: 10.1111/1462-2920.13150] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Revised: 11/18/2015] [Accepted: 11/23/2015] [Indexed: 01/03/2023]
Abstract
Fusaric acid (FSA) is a mycotoxin produced by several fusaria, including the rice pathogen Fusarium fujikuroi. Genes involved in FSA biosynthesis were previously identified as a cluster containing a polyketide synthase (PKS)-encoding (FUB1) and four additional genes (FUB2-FUB5). However, the biosynthetic steps leading to FSA as well as the origin of the nitrogen atom, which is incorporated into the polyketide backbone, remained unknown. In this study, seven additional cluster genes (FUB6-FUB12) were identified via manipulation of the global regulator FfSge1. The extended FUB gene cluster encodes two Zn(II)2 Cys6 transcription factors: Fub10 positively regulates expression of all FUB genes, whereas Fub12 is involved in the formation of the two FSA derivatives, i.e. dehydrofusaric acid and fusarinolic acid, serving as a detoxification mechanism. The major facilitator superfamily transporter Fub11 functions in the export of FSA out of the cell and is essential when FSA levels become critical. Next to Fub1, a second key enzyme was identified, the non-canonical non-ribosomal peptide synthetase Fub8. Chemical analyses of generated mutant strains allowed for the identification of a triketide as PKS product and the proposition of an FSA biosynthetic pathway, thereby unravelling the unique formation of a hybrid metabolite consisting of this triketide and an amino acid moiety.
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Affiliation(s)
- Lena Studt
- Institute of Plant Biology and Biotechnology, Westfälische Wilhelms-University, Schlossplatz 8, 48143, Münster, Germany
| | - Slavica Janevska
- Institute of Plant Biology and Biotechnology, Westfälische Wilhelms-University, Schlossplatz 8, 48143, Münster, Germany
| | - Eva-Maria Niehaus
- Institute of Plant Biology and Biotechnology, Westfälische Wilhelms-University, Schlossplatz 8, 48143, Münster, Germany
| | - Immo Burkhardt
- Kekulé Institute for Organic Chemistry and Biochemistry, Rheinische Friedrich-Wilhelms-University Bonn, 53121, Bonn, Germany
| | - Birgit Arndt
- Institute of Food Chemistry, Westfälische Wilhelms-University, Corrensstr. 45, 48149, Münster, Germany
| | - Christian M K Sieber
- Lawrence Berkeley National Lab, DOE Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA, 94598, USA
| | - Hans-Ulrich Humpf
- Institute of Food Chemistry, Westfälische Wilhelms-University, Corrensstr. 45, 48149, Münster, Germany
| | - Jeroen S Dickschat
- Kekulé Institute for Organic Chemistry and Biochemistry, Rheinische Friedrich-Wilhelms-University Bonn, 53121, Bonn, Germany
| | - Bettina Tudzynski
- Institute of Plant Biology and Biotechnology, Westfälische Wilhelms-University, Schlossplatz 8, 48143, Münster, Germany
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Arndt B, Studt L, Wiemann P, Osmanov H, Kleigrewe K, Köhler J, Krug I, Tudzynski B, Humpf HU. Genetic engineering, high resolution mass spectrometry and nuclear magnetic resonance spectroscopy elucidate the bikaverin biosynthetic pathway in Fusarium fujikuroi. Fungal Genet Biol 2015; 84:26-36. [DOI: 10.1016/j.fgb.2015.09.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Revised: 09/09/2015] [Accepted: 09/14/2015] [Indexed: 01/17/2023]
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24
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Kim M, Zhang H, Woloshuk C, Shim WB, Yoon BJ. Computational identification of genetic subnetwork modules associated with maize defense response to Fusarium verticillioides. BMC Bioinformatics 2015; 16 Suppl 13:S12. [PMID: 26423221 PMCID: PMC4597171 DOI: 10.1186/1471-2105-16-s13-s12] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Background Maize, a crop of global significance, is vulnerable to a variety of biotic stresses resulting in economic losses. Fusarium verticillioides (teleomorph Gibberella moniliformis) is one of the key fungal pathogens of maize, causing ear rots and stalk rots. To better understand the genetic mechanisms involved in maize defense as well as F. verticillioides virulence, a systematic investigation of the host-pathogen interaction is needed. The aim of this study was to computationally identify potential maize subnetwork modules associated with its defense response against F. verticillioides. Results We obtained time-course RNA-seq data from B73 maize inoculated with wild type F. verticillioides and a loss-of-virulence mutant, and subsequently established a computational pipeline for network-based comparative analysis. Specifically, we first analyzed the RNA-seq data by a cointegration-correlation-expression approach, where maize genes were jointly analyzed with known F. verticillioides virulence genes to find candidate maize genes likely associated with the defense mechanism. We predicted maize co-expression networks around the selected maize candidate genes based on partial correlation, and subsequently searched for subnetwork modules that were differentially activated when inoculated with two different fungal strains. Based on our analysis pipeline, we identified four potential maize defense subnetwork modules. Two were directly associated with maize defense response and were associated with significant GO terms such as GO:0009817 (defense response to fungus) and GO:0009620 (response to fungus). The other two predicted modules were indirectly involved in the defense response, where the most significant GO terms associated with these modules were GO:0046914 (transition metal ion binding) and GO:0046686 (response to cadmium ion). Conclusion Through our RNA-seq data analysis, we have shown that a network-based approach can enhance our understanding of the complicated host-pathogen interactions between maize and F. verticillioides by interpreting the transcriptome data in a system-oriented manner. We expect that the proposed analytic pipeline can also be adapted for investigating potential functional modules associated with host defense response in diverse plant-pathogen interactions.
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25
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Niu C, Payne GA, Woloshuk CP. Transcriptome changes in Fusarium verticillioides caused by mutation in the transporter-like gene FST1. BMC Microbiol 2015; 15:90. [PMID: 25906821 PMCID: PMC4422464 DOI: 10.1186/s12866-015-0427-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Accepted: 02/19/2015] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Fusarium verticillioides causes an important seed disease on maize and produces the fumonisin group of mycotoxins, which are toxic to humans and livestock. A previous study discovered that a gene (FST1) in the pathogen affects fumonisin production and virulence. Although the predicted amino acid sequence of FST1 is similar to hexose transporters, previous experimental evidence failed to prove function. RESULTS Three new phenotypes were identified that are associated with the FST1 mutant of F. verticillioides (Δfst1), namely reduction in macroconidia production, increased sensitivity to hydrogen peroxide, and reduced mycelial hydrophobicity. A transcriptome comparison of the wild type and strain Δfst1 grown on autoclaved maize kernels for six days identified 2677 genes that were differentially expressed. Through gene ontology analysis, 961 genes were assigned to one of 12 molecular function categories. Sets of down-regulated genes in strain Δfst1 were identified that could account for each of the mutant phenotypes. CONCLUSION The study provides evidence that disruption of FST1 causes several metabolic and developmental defects in F. verticillioides. FST1 appears to connect the expression of several gene networks, including those involved in secondary metabolism, cell wall structure, conidiogenesis, virulence, and resistance to reactive oxygen species. The results support our hypothesis that FST1 functions within the framework of environmental sensing.
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Affiliation(s)
- Chenxing Niu
- Department of Botany and Plant Pathology, Purdue University, 915 W. State Street, West Lafayette, IN, 47907-2054, USA.
| | - Gary A Payne
- Department of Plant Pathology, North Carolina State University, 851 Main Campus Drive, Raleigh, NC, 27695-7567, USA.
| | - Charles P Woloshuk
- Department of Botany and Plant Pathology, Purdue University, 915 W. State Street, West Lafayette, IN, 47907-2054, USA.
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26
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Pfannmüller A, Wagner D, Sieber C, Schönig B, Boeckstaens M, Marini AM, Tudzynski B. The General Amino Acid Permease FfGap1 of Fusarium fujikuroi Is Sorted to the Vacuole in a Nitrogen-Dependent, but Npr1 Kinase-Independent Manner. PLoS One 2015; 10:e0125487. [PMID: 25909858 PMCID: PMC4409335 DOI: 10.1371/journal.pone.0125487] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Accepted: 03/14/2015] [Indexed: 12/18/2022] Open
Abstract
The rice pathogenic fungus Fusarium fujikuroi is well known for the production of a broad spectrum of secondary metabolites (SMs) such as gibberellic acids (GAs), mycotoxins and pigments. The biosynthesis of most of these SMs strictly depends on nitrogen availability and of the activity of permeases of nitrogen sources, e.g. the ammonium and amino acid permeases. One of the three ammonium permeases, MepB, was recently shown to act not only as a transporter but also as a nitrogen sensor affecting the production of nitrogen-repressed SMs. Here we describe the identification of a general amino acid permease, FfGap1, among the 99 putative amino acid permeases (AAPs) in the genome of F. fujikuroi. FfGap1 is able to fully restore growth of the yeast gap1∆ mutant on several amino acids including citrulline and tryptophane. In S. cerevisiae, Gap1 activity is regulated by shuttling between the plasma membrane (nitrogen limiting conditions) and the vacuole (nitrogen sufficiency), which we also show for FfGap1. In yeast, the Npr1 serine/threonine kinase stabilizes the Gap1 position at the plasma membrane. Here, we identified and characterized three NPR1-homologous genes, encoding the putative protein kinases FfNpr1-1, FfNpr1-2 and FfNpr1-3 with significant similarity to yeast Npr1. Complementation of the yeast npr1Δ mutant with each of the three F. fujikuroi NPR1 homologues, resulted in partial restoration of ammonium, arginine and proline uptake by FfNPR1-1 while none of the three kinases affect growth on different nitrogen sources and nitrogen-dependent sorting of FfGap1 in F. fujikuroi. However, exchange of the putative ubiquitin-target lysine 9 (K9A) and 15 (K15A) residues of FfGap1 resulted in extended localization to the plasma membrane and increased protein stability independently of nitrogen availability. These data suggest a similar regulation of FfGap1 by nitrogen-dependent ubiquitination, but differences regarding the role of Fusarium Npr1 homologues compared to yeast.
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Affiliation(s)
- Andreas Pfannmüller
- Institut für Biologie und Biotechnologie der Pflanzen, Westfälische Wilhelms-Universität Münster, Münster, Germany
| | - Dominik Wagner
- Institut für Biologie und Biotechnologie der Pflanzen, Westfälische Wilhelms-Universität Münster, Münster, Germany
| | - Christian Sieber
- Institute of Bioinformatics and Systems Biology, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| | - Birgit Schönig
- Institut für Biologie und Biotechnologie der Pflanzen, Westfälische Wilhelms-Universität Münster, Münster, Germany
| | - Mélanie Boeckstaens
- Laboratoire de Biologie du Transport Membranaire, Institut de Biologie et de Médecine Moléculaires, Université Libre de Bruxelles, Gosselies, Belgium
| | - Anna Maria Marini
- Laboratoire de Biologie du Transport Membranaire, Institut de Biologie et de Médecine Moléculaires, Université Libre de Bruxelles, Gosselies, Belgium
| | - Bettina Tudzynski
- Institut für Biologie und Biotechnologie der Pflanzen, Westfälische Wilhelms-Universität Münster, Münster, Germany
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Ruiz-Roldán C, Pareja-Jaime Y, González-Reyes JA, Roncero MIG. The Transcription Factor Con7-1 Is a Master Regulator of Morphogenesis and Virulence in Fusarium oxysporum. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2015; 28:55-68. [PMID: 25271883 DOI: 10.1094/mpmi-07-14-0205-r] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Previous studies have demonstrated the essential role of morphogenetic regulation in Fusarium oxysporum pathogenesis, including processes such as cell-wall biogenesis, cell division, and differentiation of infection-like structures. We identified three F. oxysporum genes encoding predicted transcription factors showing significant identities to Magnaporthe oryzae Con7p, Con7-1, plus two identical copies of Con7-2. Targeted deletion of con7-1 produced nonpathogenic mutants with altered morphogenesis, including defects in cell wall structure, polar growth, hyphal branching, and conidiation. By contrast, simultaneous inactivation of both con7-2 copies caused no detectable defects in the resulting mutants. Comparative microarray-based gene expression analysis indicated that Con7-1 modulates the expression of a large number of genes involved in different biological functions, including host-pathogen interactions, morphogenesis and development, signal perception and transduction, transcriptional regulation, and primary and secondary metabolism. Taken together, our results point to Con7-1 as general regulator of morphogenesis and virulence in F. oxysporum.
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Brown DW, Busman M, Proctor RH. Fusarium verticillioides SGE1 is required for full virulence and regulates expression of protein effector and secondary metabolite biosynthetic genes. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2014; 27:809-823. [PMID: 24742071 DOI: 10.1094/mpmi-09-13-0281-r] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The transition from one lifestyle to another in some fungi is initiated by a single orthologous gene, SGE1, that regulates markedly different genes in different fungi. Despite these differences, many of the regulated genes encode effector proteins or proteins involved in the synthesis of secondary metabolites (SM), both of which can contribute to pathogenicity. Fusarium verticillioides is both an endophyte and a pathogen of maize and can grow as a saprophyte on dead plant material. During growth on live maize plants, the fungus can synthesize a number of toxic SM, including fumonisins, fusarins, and fusaric acid, that can contaminate kernels and kernel-based food and feed. In this study, the role of F. verticillioides SGE1 in pathogenicity and secondary metabolism was examined by gene deletion analysis and transcriptomics. SGE1 is not required for vegetative growth or conidiation but is required for wild-type pathogenicity and affects synthesis of multiple SM, including fumonisins and fusarins. Induced expression of SGE1 enhanced or reduced expression of hundreds of genes, including numerous putative effector genes that could contribute to growth in planta; genes encoding cell surface proteins; gene clusters required for synthesis of fusarins, bikaverin, and an unknown metabolite; as well as the gene encoding the fumonisin cluster transcriptional activator. Together, our results indicate that SGE1 has a role in global regulation of transcription in F. verticillioides that impacts but is not absolutely required for secondary metabolism and pathogenicity on maize.
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29
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Eugenia de la Torre-Hernández M, Sánchez-Rangel D, Galeana-Sánchez E, Plasencia-de la Parra J. Fumonisinas –Síntesis y función en la interacción Fusarium verticillioides-maíz. TIP REVISTA ESPECIALIZADA EN CIENCIAS QUÍMICO-BIOLÓGICAS 2014. [DOI: 10.1016/s1405-888x(14)70321-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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Ridenour JB, Bluhm BH. The HAP complex in Fusarium verticillioides is a key regulator of growth, morphogenesis, secondary metabolism, and pathogenesis. Fungal Genet Biol 2014; 69:52-64. [PMID: 24875423 DOI: 10.1016/j.fgb.2014.05.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Revised: 05/14/2014] [Accepted: 05/15/2014] [Indexed: 11/28/2022]
Abstract
Among eukaryotic organisms, the HAP complex is a conserved, multimeric transcription factor that regulates gene expression by binding to the consensus sequence CCAAT. In filamentous fungi, the HAP complex has been linked to primary and secondary metabolism, but its role in pathogenesis has not been investigated extensively. The overarching goal of this study was to elucidate the role of the HAP complex in Fusariumverticillioides, a ubiquitous and damaging pathogen of maize. To this end, orthologs of core HAP complex genes (FvHAP2, FvHAP3, and FvHAP5) were identified and deleted in F. verticillioides via a reverse genetics approach. Deletion of FvHAP2, FvHAP3, or FvHAP5 resulted in an indistinguishable phenotype among the deletion strains, including reduced radial growth and conidiation, altered colony morphology, and derepression of pigmentation. Additionally, disruption of the HAP complex impaired infection and colonization of maize stalks. Deletion strains were hypersensitive to osmotic and oxidative stress, which suggests the HAP complex of F. verticillioides may mediate responses to environmental stress during pathogenesis. This study directly implicates the HAP complex in primary and secondary metabolism in F. verticillioides and provides one of the first links between the HAP complex and virulence in a plant pathogenic fungus.
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Affiliation(s)
- John B Ridenour
- Department of Plant Pathology, University of Arkansas, Division of Agriculture, Fayetteville, AR 72701, USA
| | - Burton H Bluhm
- Department of Plant Pathology, University of Arkansas, Division of Agriculture, Fayetteville, AR 72701, USA.
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31
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Ridenour JB, Smith JE, Hirsch RL, Horevaj P, Kim H, Sharma S, Bluhm BH. UBL1 of Fusarium verticillioides links the N-end rule pathway to extracellular sensing and plant pathogenesis. Environ Microbiol 2013; 16:2004-22. [PMID: 24237664 DOI: 10.1111/1462-2920.12333] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Accepted: 11/07/2013] [Indexed: 01/06/2023]
Abstract
Fusarium verticillioides produces fumonisin mycotoxins during colonization of maize. Currently, molecular mechanisms underlying responsiveness of F.verticillioides to extracellular cues during pathogenesis are poorly understood. In this study, insertional mutants were created and screened to identify genes involved in responses to extracellular starch. In one mutant, the restriction enzyme-mediated integration cassette disrupted a gene (UBL1) encoding a UBR-Box/RING domain E3 ubiquitin ligase involved in the N-end rule pathway. Disruption of UBL1 in F.verticillioides (Δubl1) influenced conidiation, hyphal morphology, pigmentation and amylolysis. Disruption of UBL1 also impaired kernel colonization, but the ratio of fumonisin B1 per unit growth was not significantly reduced. The inability of a Δubl1 mutant to recognize an N-end rule degron confirmed involvement of UBL1 in the N-end rule pathway. Additionally, Ubl1 physically interacted with two G protein α subunits of F.verticillioides, thus implicating UBL1 in G protein-mediated sensing of the external environment. Furthermore, deletion of the UBL1 orthologue in F.graminearum reduced virulence on wheat and maize, thus indicating that UBL1 has a broader role in virulence among Fusarium species. This study provides the first linkage between the N-end rule pathway and fungal pathogenesis, and illustrates a new mechanism through which fungi respond to the external environment.
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Affiliation(s)
- John B Ridenour
- Department of Plant Pathology, Division of Agriculture, University of Arkansas, Fayetteville, AR, 72701, USA
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32
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Chang PK, Ehrlich KC. Genome-wide analysis of the Zn(II)2Cys6 zinc cluster-encoding gene family in Aspergillus flavus. Appl Microbiol Biotechnol 2013; 97:4289-300. [DOI: 10.1007/s00253-013-4865-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2013] [Revised: 03/13/2013] [Accepted: 03/18/2013] [Indexed: 12/16/2022]
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Woloshuk CP, Shim WB. Aflatoxins, fumonisins, and trichothecenes: a convergence of knowledge. FEMS Microbiol Rev 2012; 37:94-109. [PMID: 23078349 DOI: 10.1111/1574-6976.12009] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Revised: 09/27/2012] [Accepted: 10/15/2012] [Indexed: 01/03/2023] Open
Abstract
Plant pathogenic fungi Aspergillus flavus, Fusarium verticillioides, and Fusarium graminearum infect seeds of the most important food and feed crops, including maize, wheat, and barley. More importantly, these fungi produce aflatoxins, fumonisins, and trichothecenes, respectively, which threaten health and food security worldwide. In this review, we examine the molecular mechanisms and environmental factors that regulate mycotoxin biosynthesis in each fungus, and discuss the similarities and differences in the collective body of knowledge. Whole-genome sequences are available for these fungi, providing reference databases for genomic, transcriptomic, and proteomic analyses. It is well recognized that genes responsible for mycotoxin biosynthesis are organized in clusters. However, recent research has documented the intricate transcriptional and epigenetic regulation that affects these gene clusters. Significantly, molecular networks that respond to environmental factors, namely nitrogen, carbon, and pH, are connected to components regulating mycotoxin production. Furthermore, the developmental status of seeds and specific tissue types exert conditional influences during fungal colonization. A comparison of the three distinct mycotoxin groups provides insight into new areas for research collaborations that will lead to innovative strategies to control mycotoxin contamination of grain.
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Affiliation(s)
- Charles P Woloshuk
- Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA.
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34
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Butchko RAE, Brown DW, Busman M, Tudzynski B, Wiemann P. Lae1 regulates expression of multiple secondary metabolite gene clusters in Fusarium verticillioides. Fungal Genet Biol 2012; 49:602-12. [PMID: 22713715 DOI: 10.1016/j.fgb.2012.06.003] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Revised: 06/01/2012] [Accepted: 06/10/2012] [Indexed: 11/18/2022]
Abstract
The filamentous fungus Fusarium verticillioides can cause disease of maize and is capable of producing fumonisins, a family of toxic secondary metabolites linked to esophageal cancer and neural tube defects in humans and lung edema in swine and leukoencephalomalacia in equines. The expression of fumonisin biosynthetic genes is influenced by broad-domain transcription factors (global regulators) and Fum21, a pathway-specific transcription factor. LaeA is a global regulator that in Aspergillus nidulans, affects the expression of multiple secondary metabolite gene clusters by modifying heterochromatin structure. Here, we employed gene deletion analysis to assess the effect of loss of a F. verticillioides laeA orthologue, LAE1, on genome-wide gene expression and secondary metabolite production. Loss of Lae1 resulted in reduced expression of gene clusters responsible for synthesis of the secondary metabolites bikaverin, fumonisins, fusaric acid and fusarins as well as two clusters for which the corresponding secondary metabolite is unknown. Analysis of secondary metabolites revealed that, in contrast to a previously described Fusarium fujikuroi lae1 mutant, bikaverin production is reduced. Fumonisin production is unchanged in the F. verticillioides lae1 mutant. Complementation of the F. verticillioides mutant resulted in increased fumonisin production.
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Affiliation(s)
- Robert A E Butchko
- National Center for Agricultural Utilization Research, Peoria, IL, United States.
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35
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Ravalason H, Grisel S, Chevret D, Favel A, Berrin JG, Sigoillot JC, Herpoël-Gimbert I. Fusarium verticillioides secretome as a source of auxiliary enzymes to enhance saccharification of wheat straw. BIORESOURCE TECHNOLOGY 2012; 114:589-96. [PMID: 22459963 DOI: 10.1016/j.biortech.2012.03.009] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2011] [Revised: 02/13/2012] [Accepted: 03/02/2012] [Indexed: 05/25/2023]
Abstract
Fusarium verticillioides secretes enzymes (secretome), some of which might be potentially useful for saccharification of lignocellulosic biomass since supplementation of commercial cellulases from Trichoderma reesei with the F. verticillioides secretome improved the enzymatic release of glucose, xylose and arabinose from wheat straw by 24%, 88% and 68%, respectively. Determination of enzymatic activities revealed a broad range of hemicellulases and pectinases poorly represented in commercial cocktails. Proteomics approaches identified 57 proteins potentially involved in lignocellulose breakdown among a total of 166 secreted proteins. This analysis highlighted the presence of carbohydrate-active enzymes (CAZymes) targeting pectin (from glycoside hydrolase families GH5, GH27, GH28, GH43, GH51, GH54, GH62, GH88 and GH93, polysaccharide lyase family PL4 and carbohydrate esterase family CE8) and hemicelluloses (from glycoside hydrolase families GH3, GH10, GH11, GH30, GH39, GH43 and GH67). These data provide a first step towards the identification of candidates to supplement T. reesei enzyme preparations for lignocellulose hydrolysis.
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Affiliation(s)
- Holy Ravalason
- INRA, UMR 1163 Biotechnologie des Champignons Filamenteux, 13288 Marseille, France.
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Sun X, Yu L, Lan N, Wei S, Yu Y, Zhang H, Zhang X, Li S. Analysis of the role of transcription factor VAD-5 in conidiation of Neurospora crassa. Fungal Genet Biol 2012; 49:379-87. [PMID: 22445960 DOI: 10.1016/j.fgb.2012.03.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2011] [Revised: 03/01/2012] [Accepted: 03/07/2012] [Indexed: 11/29/2022]
Abstract
Conidiation is the major mode of reproduction in many filamentous fungi. The Neurospora crassa gene vad-5, which encodes a GAL4-like Zn2Cys6 transcription factor, was suggested to contribute to conidiation in a previous study using a knockout mutant. In this study, we confirmed the positive contribution of vad-5 to conidiation by gene complementation. To understand the role of vad-5 in conidiation, transcriptomic profiles generated by digital gene expression profiling from the vad-5 deletion mutant and the wild-type strain were compared. Among 7559 detected genes, 176 genes were found to be transcriptionally down-regulated and 277 genes transcriptionally upregulated in the vad-5 deletion mutant, using ≥1-fold change as a cutoff threshold. Among the down-regulated genes, four which were already known to be involved in conidiation -fluffy, ada-6, rca-1, and eas - were examined further in a time course experiment. Transcription of each of the four genes in the vad-5 deletion mutant was lower than in the wild-type strain during conidial development. Phenotypic observation of deletion mutants for 132 genes down-regulated by vad-5 deletion revealed that deletion mutants for 17 genes, including fluffy, ada-6, and eas, produced fewer conidia than the wild type. By phenotypic observation of deletion mutants for 211 genes upregulated in the vad-5 deletion mutant, two types of deletion mutants were found. One type, which produced more conidia than the wild-type strain, includes deletion mutants for previously characterized genes cat-2, cat-3, and sah-1 and for a non-characterized gene NCU07221. Deletion mutants of NCU06302 and NCU11090, representing the second type, produced conidia earlier than the wild-type strain. Based on these conidiation phenotypes, we designated NCU07221 as high conidial production-1 (hcp-1) and named NCU06302 and NCU11090 as early conidial development-1 (ecd-1) and ecd-2, respectively. Given the collective results from this study, we propose that vad-5 exerts an effect on conidiation by activating genes that positively contribute to conidiation as well as by repressing genes that negatively influence conidial development.
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Affiliation(s)
- Xianyun Sun
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100080, China
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Picot A, Barreau C, Pinson-Gadais L, Piraux F, Caron D, Lannou C, Richard-Forget F. The dent stage of maize kernels is the most conducive for fumonisin biosynthesis under field conditions. Appl Environ Microbiol 2011; 77:8382-90. [PMID: 21984235 PMCID: PMC3233062 DOI: 10.1128/aem.05216-11] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Accepted: 09/27/2011] [Indexed: 11/20/2022] Open
Abstract
The fungal pathogen Fusarium verticillioides infects maize ears and produces fumonisins, known for their adverse effects on human and animal health. Basic questions remain unanswered regarding the kernel stage(s) associated with fumonisin biosynthesis and the kernel components involved in fumonisin regulation during F. verticillioides-maize interaction under field conditions. In this 2-year field study, the time course of F. verticillioides growth and fumonisin accumulation in developing maize kernels, along with the variations in kernel pH and amylopectin content, were monitored using relevant and accurate analytical tools. In all experiments, the most significant increase in fumonisin accumulation or in fumonisin productivity (i.e., fumonisin production per unit of fungus) was shown to occur within a very short period of time, between 22/32 and 42 days after inoculation and corresponding to the dent stage. This stage was also characterized by acidification in the kernel pH and a maximum level of amylopectin content. Our data clearly support published results based on in vitro experiments suggesting that the physiological stages of the maize kernel play a major role in regulating fumonisin production. Here we have validated this result for in planta and field conditions, and we demonstrate that under such conditions the dent stage is the most conducive for fumonisin accumulation.
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Affiliation(s)
- Adeline Picot
- ARVALIS-Institut du Végétal, 6 Chemin de la Côte Vieille, F-31 450 Baziège
- INRA UR1264 MycSA, 71 Avenue Edouard Bourlaux, F-33 883 Villenave d'Ornon
- INRA UMR1290 BIOGER, BP01, F-78 850 Thiverval-Grignon
| | - Christian Barreau
- CNRS INRA UR1264 MycSA, 71 Avenue Edouard Bourlaux, F-33 883 Villenave d'Ornon, France
| | | | - François Piraux
- ARVALIS-Institut du Végétal, Station Expérimentale de Boigneville, F-91 720 Boigneville
| | - Daniel Caron
- ARVALIS-Institut du Végétal, 6 Chemin de la Côte Vieille, F-31 450 Baziège
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Kim H, Ridenour JB, Dunkle LD, Bluhm BH. Regulation of stomatal tropism and infection by light in Cercospora zeae-maydis: evidence for coordinated host/pathogen responses to photoperiod? PLoS Pathog 2011; 7:e1002113. [PMID: 21829344 PMCID: PMC3145785 DOI: 10.1371/journal.ppat.1002113] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2010] [Accepted: 04/25/2011] [Indexed: 01/23/2023] Open
Abstract
Cercospora zeae-maydis causes gray leaf spot of maize, which has become one of the most widespread and destructive diseases of maize in the world. C. zeae-maydis infects leaves through stomata, which is predicated on the ability of the pathogen to perceive stomata and reorient growth accordingly. In this study, the discovery that light was required for C. zeae-maydis to perceive stomata and infect leaves led to the identification of CRP1, a gene encoding a putative blue-light photoreceptor homologous to White Collar-1 (WC-1) of Neurospora crassa. Disrupting CRP1 via homologous recombination revealed roles in multiple aspects of pathogenesis, including tropism of hyphae to stomata, the formation of appressoria, conidiation, and the biosynthesis of cercosporin. CRP1 was also required for photoreactivation after lethal doses of UV exposure. Intriguingly, putative orthologs of CRP1 are central regulators of circadian clocks in other filamentous fungi, raising the possibility that C. zeae-maydis uses light as a key environmental input to coordinate pathogenesis with maize photoperiodic responses. This study identified a novel molecular mechanism underlying stomatal tropism in a foliar fungal pathogen, provides specific insight into how light regulates pathogenesis in C. zeae-maydis, and establishes a genetic framework for the molecular dissection of infection via stomata and the integration of host and pathogen responses to photoperiod.
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Affiliation(s)
- Hun Kim
- Department of Plant Pathology, University of Arkansas, Fayetteville, Arkansas, United States of America
| | - John B. Ridenour
- Department of Plant Pathology, University of Arkansas, Fayetteville, Arkansas, United States of America
| | - Larry D. Dunkle
- Crop Production and Pest Control Research Unit, USDA-ARS, Purdue University, West Lafayette, Indiana, United States of America
| | - Burton H. Bluhm
- Department of Plant Pathology, University of Arkansas, Fayetteville, Arkansas, United States of America
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Reese BN, Payne GA, Nielsen DM, Woloshuk CP. Gene expression profile and response to maize kernels by Aspergillus flavus. PHYTOPATHOLOGY 2011; 101:797-804. [PMID: 21341988 DOI: 10.1094/phyto-09-10-0261] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Aspergillus flavus causes an ear rot of maize, often resulting in the production of aflatoxin, a potent liver toxin and carcinogen that impacts the health of humans and animals. Many aspects of kernel infection and aflatoxin biosynthesis have been studied but the precise effects of the kernel environment on A. flavus are poorly understood. The goal of this research was to study the fungal response to the kernel environment during colonization. Gene transcription in A. flavus was analyzed by microarrays after growth on kernels of the four developmental stages: blister (R2), milk (R3), dough (R4), and dent (R5). Five days after inoculation, total RNA was isolated from kernels and hybridized to Affymetrix Gene Chip arrays containing probes representing 12,834 A. flavus genes. Statistical comparisons of the expression profile data revealed significant differences that included unique sets of upregulated genes in each kernel stage and six patterns of expression over the four stages. Among the genes expressed in colonized dent kernels were a phytase gene and six putative genes involved in zinc acquisition. Disruption of the phytase gene phy1 resulted in reduced growth on medium containing phytate as the sole source of phosphate. Furthermore, growth of the mutant (Δphy1) was 20% of the wild-type strain when wound inoculated into maize ears. In contrast, no difference was detected in the amount of aflatoxin produced relative to fungal growth, indicating that phy1 does not affect aflatoxin production. The study revealed the genome-wide effects of immature maize kernels on A. flavus and suggest that phytase has a role in pathogenesis.
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Affiliation(s)
- Brittiney N Reese
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA
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Kim H, Smith JE, Ridenour JB, Woloshuk CP, Bluhm BH. HXK1 regulates carbon catabolism, sporulation, fumonisin B₁ production and pathogenesis in Fusarium verticillioides. MICROBIOLOGY-SGM 2011; 157:2658-2669. [PMID: 21719539 DOI: 10.1099/mic.0.052506-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In Fusarium verticillioides, a ubiquitous pathogen of maize, virulence and mycotoxigenesis are regulated in response to the types and amounts of carbohydrates present in maize kernels. In this study, we investigated the role of a putative hexokinase-encoding gene (HXK1) in growth, development and pathogenesis. A deletion mutant (Δhxk1) of HXK1 was not able to grow when supplied with fructose as the sole carbon source, and growth was impaired when glucose, sucrose or maltotriose was provided. Additionally, the Δhxk1 mutant produced unusual swollen hyphae when provided with fructose, but not glucose, as the sole carbon source. Moreover, the Δhxk1 mutant was impaired in fructose uptake, although glucose uptake was unaffected. On maize kernels, the Δhxk1 mutant was substantially less virulent than the wild-type, but virulence on maize stalks was not impaired, possibly indicating a metabolic response to tissue-specific differences in plant carbohydrate content. Finally, disruption of HXK1 had a pronounced effect on fungal metabolites produced during colonization of maize kernels; the Δhxk1 mutant produced approximately 50 % less trehalose and 80 % less fumonisin B₁ (FB₁) than the wild-type. The reduction in trehalose biosynthesis likely explains observations of increased sensitivity to osmotic stress in the Δhxk1 mutant. In summary, this study links early events in carbohydrate sensing and glycolysis to virulence and secondary metabolism in F. verticillioides, and thus provides a new foothold from which the genetic regulatory networks that underlie pathogenesis and mycotoxigenesis can be unravelled and defined.
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Affiliation(s)
- Hun Kim
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA.,Department of Plant Pathology, University of Arkansas, Fayetteville, AR 72701, USA
| | - Jonathon E Smith
- Department of Plant Pathology, University of Arkansas, Fayetteville, AR 72701, USA
| | - John B Ridenour
- Department of Plant Pathology, University of Arkansas, Fayetteville, AR 72701, USA
| | - Charles P Woloshuk
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA
| | - Burton H Bluhm
- Department of Plant Pathology, University of Arkansas, Fayetteville, AR 72701, USA
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Kim H, Woloshuk CP. Functional characterization of fst1 in Fusarium verticillioides during colonization of maize kernels. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2011; 24:18-24. [PMID: 20854112 DOI: 10.1094/mpmi-03-10-0074] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The putative hexose transporter gene fst1 in Fusarium verticillioides was identified previously by microarray analysis as a gene that was more highly expressed during colonization of autoclaved maize endosperm than germ. In contrast to a previous study, in which disruption of fst1 did not affect growth of the pathogen on autoclaved maize kernels, in the current study, we demonstrated that disruption of fst1 delayed growth and symptom development on wounded maize ears. Characterization of the fst1 promoter revealed that regulation of fst1 expression was similar to that of fumonisin biosynthetic (fum) genes; expression was highest during growth on endosperm tissue and repressed by elevated concentrations of ammonium in the growth medium. With a fluorescent tag attached to FST1, the protein localized transiently to the periphery of the cells near the plasma membrane and in vacuole-like structures, suggesting that membrane-localized FST1 was internalized and degraded in vacuoles. Expression of fst1 in a yeast strain lacking hexose transporter genes did not complement the yeast mutation, suggesting that FST1 does not transport glucose, fructose, or mannose. The results indicate a functional role for FST1 in pathogenesis during the colonization of living kernels.
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Affiliation(s)
- Hun Kim
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA
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Brown DW. The KP4 killer protein gene family. Curr Genet 2010; 57:51-62. [DOI: 10.1007/s00294-010-0326-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2010] [Revised: 11/03/2010] [Accepted: 11/05/2010] [Indexed: 11/28/2022]
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Picot A, Barreau C, Pinson-Gadais L, Caron D, Lannou C, Richard-Forget F. Factors of theFusarium verticillioides-maize environment modulating fumonisin production. Crit Rev Microbiol 2010; 36:221-31. [DOI: 10.3109/10408411003720209] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Bluhm BH, Zhao X. Measuring protein kinase and sugar kinase activity in plant pathogenic fusarium species. Methods Mol Biol 2010; 638:201-210. [PMID: 20238271 DOI: 10.1007/978-1-60761-611-5_15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
As ubiquitous metabolic and signaling intermediaries, kinases regulate innumerable aspects of fungal growth and development. At its simplest, the enzymatic function of a kinase is to transfer a phosphate from a donor molecule (such as adenosine triphosphate) to an acceptor molecule, such as a protein, carbohydrate, or lipid. Kinase activity is intricately interwoven into signal transduction, and ultimately modulates gene expression, downstream phosphorylation events, and other mechanisms of posttranslational modification. Therefore, sensitive and reproducible techniques to measure kinase activity are crucial to elucidate cellular signaling and for fungal functional genomics.Protein and sugar kinases regulate multiple aspects of pathogenesis in the mycotoxigenic, plant pathogenic fungi Fusarium graminearum, and Fusarium verticillioides. Here, we present protocols to (1) quantify phosphorylation of mitogen-activated protein kinases in F. graminearum, and (2) determine glucokinase activity in F. verticillioides. The mitogen-activated protein kinase phosphorylation assay utilizes immunological methods to quantify substrate phosphorylation, whereas the glucokinase assay is a coupled enzyme assay, in which phosphorylation of glucose by glucokinase is measured indirectly through the subsequent reduction of NADP+ to NADPH, a substrate more amenable for spectrophotometric detection.
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Affiliation(s)
- Burton H Bluhm
- Department of Plant Pathology, Division of Agriculture, University of Arkansas, Fayetteville, AR, USA
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MYUNG KYUNG, LI SHAOJIE, BUTCHKO ROBERTA, BUSMAN MARK, PROCTOR ROBERTH, ABBAS HAMEDK, CALVO ANAM. FvVE1 regulates biosynthesis of the mycotoxins fumonisins and fusarins in Fusarium verticillioides. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2009; 57:5089-94. [PMID: 19382792 PMCID: PMC2692565 DOI: 10.1021/jf900783u] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The veA gene positively regulates sterigmatocystin production in Aspergillus nidulans and aflatoxin production in Aspergillus parasiticus and Aspergillus flavus . Whether veA homologues have a role in regulating secondary metabolism in other fungal genera is unknown. In this study, we examined the role of the veA homologue, FvVE1, on the production of two mycotoxin families, fumonisins and fusarins, in the important corn pathogen Fusarium verticillioides . We found that FvVE1 deletion completely suppressed fumonisin production on two natural substrates, corn and rice. Furthermore, our results revealed that FvVE1 is necessary for the expression of the pathway-specific regulatory gene FUM21 and structural genes in the fumonisin biosynthetic gene (FUM) cluster. FvVE1 deletion also blocked production of fusarins. The effects of FvVE1 deletion on the production of these toxins were found to be the same in two separate mating types. Our results strongly suggest that FvVE1 plays an important role in regulating mycotoxin production in F. verticillioides .
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Affiliation(s)
- KYUNG MYUNG
- Department of Biological Sciences, Northern Illinois University, 1425 W. Lincoln Hwy., Dekalb, Illinois 60115. USA
| | - SHAOJIE LI
- Department of Biological Sciences, Northern Illinois University, 1425 W. Lincoln Hwy., Dekalb, Illinois 60115. USA
| | - ROBERT A.E. BUTCHKO
- Mycotoxin Research Unit, US Department of Agriculture-ARS, 1815 N. University Street, Peoria, Illinois 61604, USA
| | - MARK BUSMAN
- Mycotoxin Research Unit, US Department of Agriculture-ARS, 1815 N. University Street, Peoria, Illinois 61604, USA
| | - ROBERT H PROCTOR
- Mycotoxin Research Unit, US Department of Agriculture-ARS, 1815 N. University Street, Peoria, Illinois 61604, USA
| | - HAMED K. ABBAS
- Crop Genetics and Production Research Unit, US Department of Agriculture-ARS, CG&PRU, P.O. Box 345 Stoneville, Mississippi 38776, USA
| | - ANA M. CALVO
- Department of Biological Sciences, Northern Illinois University, 1425 W. Lincoln Hwy., Dekalb, Illinois 60115. USA
- Author to whom correspondence should be addressed [telephone: (815) 753−0451; fax (815) 753−0461; e-mail ]
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Bluhm B, Dunkle L. PHL1 of Cercospora zeae-maydis encodes a member of the photolyase/cryptochrome family involved in UV protection and fungal development. Fungal Genet Biol 2008; 45:1364-72. [DOI: 10.1016/j.fgb.2008.07.005] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2008] [Revised: 07/08/2008] [Accepted: 07/08/2008] [Indexed: 10/21/2022]
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