1
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Kretschmer M, Damoo D, Sun S, Lee CWJ, Croll D, Brumer H, Kronstad J. Organic acids and glucose prime late-stage fungal biotrophy in maize. Science 2022; 376:1187-1191. [PMID: 35679407 DOI: 10.1126/science.abo2401] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Many plant-associated fungi are obligate biotrophs that depend on living hosts to proliferate. However, little is known about the molecular basis of the biotrophic lifestyle, despite the impact of fungi on the environment and food security. In this work, we show that combinations of organic acids and glucose trigger phenotypes that are associated with the late stage of biotrophy for the maize pathogen Ustilago maydis. These phenotypes include the expression of a set of effectors normally observed only during biotrophic development, as well as the formation of melanin associated with sporulation in plant tumors. U. maydis and other hemibiotrophic fungi also respond to a combination of carbon sources with enhanced proliferation. Thus, the response to combinations of nutrients from the host may be a conserved feature of fungal biotrophy.
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Affiliation(s)
- Matthias Kretschmer
- Michael Smith Laboratories and Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada
| | - Djihane Damoo
- Michael Smith Laboratories and Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada
| | - Sherry Sun
- Michael Smith Laboratories and Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada
| | - Christopher W J Lee
- Michael Smith Laboratories and Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada
| | - Daniel Croll
- Laboratory of Evolutionary Genetics, Institute of Biology, Université de Neuchâtel, Neuchâtel, Switzerland
| | - Harry Brumer
- Michael Smith Laboratories and Department of Chemistry, University of British Columbia, Vancouver, BC, Canada
| | - James Kronstad
- Michael Smith Laboratories and Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada
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2
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The Destructive Fungal Pathogen Botrytis cinerea-Insights from Genes Studied with Mutant Analysis. Pathogens 2020; 9:pathogens9110923. [PMID: 33171745 PMCID: PMC7695001 DOI: 10.3390/pathogens9110923] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 11/01/2020] [Accepted: 11/04/2020] [Indexed: 12/03/2022] Open
Abstract
Botrytis cinerea is one of the most destructive fungal pathogens affecting numerous plant hosts, including many important crop species. As a molecularly under-studied organism, its genome was only sequenced at the beginning of this century and it was recently updated with improved gene annotation and completeness. In this review, we summarize key molecular studies on B. cinerea developmental and pathogenesis processes, specifically on genes studied comprehensively with mutant analysis. Analyses of these studies have unveiled key genes in the biological processes of this pathogen, including hyphal growth, sclerotial formation, conidiation, pathogenicity and melanization. In addition, our synthesis has uncovered gaps in the present knowledge regarding development and virulence mechanisms. We hope this review will serve to enhance the knowledge of the biological mechanisms behind this notorious fungal pathogen.
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3
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Ma Z, Chen Z, Wang W, Wang K, Zhu T. Exocyst subunit BcSec3 regulates growth, development and pathogenicity in Botrytis cinerea. J Biosci 2020. [DOI: 10.1007/s12038-020-00097-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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4
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Guan W, Feng J, Wang R, Ma Z, Wang W, Wang K, Zhu T. Functional analysis of the exocyst subunit BcExo70 in Botrytis cinerea. Curr Genet 2019; 66:85-95. [PMID: 31183512 DOI: 10.1007/s00294-019-01002-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 05/30/2019] [Accepted: 06/01/2019] [Indexed: 01/27/2023]
Abstract
Botrytis cinerea is one of the most important saprophytic plant pathogenic fungi. The exocyst complex and exocytosis was demonstrated to be involved in fungal development and plant infection. Here, we investigated the function of an exocyst subunit gene Bcexo70 in B. cinerea. The results show that knockout of the Bcexo70 gene significantly reduced the fungal growth and hindered the production of conidia and sclerotia. The Bcexo70 deletion strains showed a severe decrease in virulence toward tomato leaves and reduced secretion of cell wall-degrading enzyme. Confocal and electronic microscopic observation showed that the vesicles in the Bcexo70 mutants were enlarged and scattered in the cytoplasm compared to the regular distribution in the hyphal tip in wild-type strain. This study showed that the exocyst gene Bcexo70 is crucial for fungal growth, conidiation and pathogenicity in B. cinerea.
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Affiliation(s)
- Wenqing Guan
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, Zhejiang, China
| | - Juan Feng
- Taizhou Vocational College of Science and Technology, Taizhou, Zhejiang, China
| | - Rongxia Wang
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, Zhejiang, China
| | - Zhiwei Ma
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, Zhejiang, China
| | - Weixia Wang
- State Key Lab of Rice Biology, China National Rice Research Institute, Hangzhou, Zhejiang, China.
| | - Kun Wang
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, Zhejiang, China.
| | - Tingheng Zhu
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, Zhejiang, China.
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5
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Yan Y, Yuan Q, Tang J, Huang J, Hsiang T, Wei Y, Zheng L. Colletotrichum higginsianum as a Model for Understanding Host⁻Pathogen Interactions: A Review. Int J Mol Sci 2018; 19:E2142. [PMID: 30041456 PMCID: PMC6073530 DOI: 10.3390/ijms19072142] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 07/18/2018] [Accepted: 07/18/2018] [Indexed: 11/16/2022] Open
Abstract
Colletotrichum higginsianum is a hemibiotrophic ascomycetous fungus that causes economically important anthracnose diseases on numerous monocot and dicot crops worldwide. As a model pathosystem, the Colletotrichum⁻Arabidopsis interaction has the significant advantage that both organisms can be manipulated genetically. The goal of this review is to provide an overview of the system and to point out recent significant studies that update our understanding of the pathogenesis of C. higginsianum and resistance mechanisms of Arabidopsis against this hemibiotrophic fungus. The genome sequence of C. higginsianum has provided insights into how genome structure and pathogen genetic variability has been shaped by transposable elements, and allows systematic approaches to longstanding areas of investigation, including infection structure differentiation and fungal⁻plant interactions. The Arabidopsis-Colletotrichum pathosystem provides an integrated system, with extensive information on the host plant and availability of genomes for both partners, to illustrate many of the important concepts governing fungal⁻plant interactions, and to serve as an excellent starting point for broad perspectives into issues in plant pathology.
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Affiliation(s)
- Yaqin Yan
- The Key Lab of Plant Pathology of Hubei Province, Huazhong Agricultural University, Wuhan 430070, China.
| | - Qinfeng Yuan
- The Key Lab of Plant Pathology of Hubei Province, Huazhong Agricultural University, Wuhan 430070, China.
| | - Jintian Tang
- The Key Lab of Plant Pathology of Hubei Province, Huazhong Agricultural University, Wuhan 430070, China.
| | - Junbin Huang
- The Key Lab of Plant Pathology of Hubei Province, Huazhong Agricultural University, Wuhan 430070, China.
| | - Tom Hsiang
- School of Environmental Sciences, University of Guelph, Guelph, ON N1G 2W1, Canada.
| | - Yangdou Wei
- Department of Biology, University of Saskatchewan, Saskatoon, SK S7N 5E2, Canada.
| | - Lu Zheng
- The Key Lab of Plant Pathology of Hubei Province, Huazhong Agricultural University, Wuhan 430070, China.
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Guo H, Huang T, Zhao J, Chen H, Chen G. Fungi short-chain carboxylate transporter: shift from microbe hereditary functional component to metabolic engineering target. Appl Microbiol Biotechnol 2018; 102:4653-4662. [PMID: 29679102 DOI: 10.1007/s00253-018-9010-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 04/05/2018] [Accepted: 04/10/2018] [Indexed: 11/29/2022]
Abstract
Short-chain carboxylic acids and their derivatives are widely utilized in all aspects of our daily life. Given their specific functional groups, these molecules are also utilized in fine chemical synthesis. The traditional petroleum-based carboxylate production methods are restricted by petrol shortage and environmental pollution. Renowned for their more sustainable processes than traditional methods, biotechnological methods are preferred alternatives and have attracted increasing attention. However, the industrial application of biotechnological methods is currently limited by low factors: low productivity and low yield. Therefore, understanding the regulation of carboxylate accumulation will greatly enhance the industrial biotechnological production of short-chain carboxylate acids. The carboxylate transporter plays a crucial role in transmembrane uptake and secretion of carboxylate; therefore, regulating these transporters is of high academic and application relevance. This review concentrates on the physiological roles, regulation mechanisms, and harnessing strategies of Jen and AcpA orthologs in fungi, which provide potential clues for the biotechnological production of short-chain carboxylic acids with high efficiency.
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Affiliation(s)
- Hongwei Guo
- Department of Biotechnology and Bioengineering, School of Chemical Engineering and Key Laboratory of Fujian Province for Biochemical Technology, National Huaqiao University, 668 Jimei Road, Amoy, 361021, Fujian, China.
| | - Tianqiu Huang
- Department of Biotechnology and Bioengineering, School of Chemical Engineering and Key Laboratory of Fujian Province for Biochemical Technology, National Huaqiao University, 668 Jimei Road, Amoy, 361021, Fujian, China
| | - Jun Zhao
- Department of Biotechnology and Bioengineering, School of Chemical Engineering and Key Laboratory of Fujian Province for Biochemical Technology, National Huaqiao University, 668 Jimei Road, Amoy, 361021, Fujian, China
| | - Hongwen Chen
- Department of Biotechnology and Bioengineering, School of Chemical Engineering and Key Laboratory of Fujian Province for Biochemical Technology, National Huaqiao University, 668 Jimei Road, Amoy, 361021, Fujian, China
| | - Guo Chen
- Department of Biotechnology and Bioengineering, School of Chemical Engineering and Key Laboratory of Fujian Province for Biochemical Technology, National Huaqiao University, 668 Jimei Road, Amoy, 361021, Fujian, China
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7
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Ren W, Sang C, Shi D, Song X, Zhou M, Chen C. Ubiquitin-like activating enzymes BcAtg3 and BcAtg7 participate in development and pathogenesis of Botrytis cinerea. Curr Genet 2018; 64:919-930. [PMID: 29417220 DOI: 10.1007/s00294-018-0810-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2017] [Revised: 01/29/2018] [Accepted: 02/02/2018] [Indexed: 11/26/2022]
Abstract
In eukaryotes, the ubiquitin-like (UBL) protein-activating enzymes play a crucial role in autophagy process, however, it is poorly characterized in filamentous fungi. Here, we investigated the functions of two UBL activating enzymes, BcAtg3 (E2) and BcAtg7 (E1) in the plant pathogenic fungus Botrytis cinerea. The physical interaction of BcAtg3 with BcAtg7 was demonstrated by yeast two-hybrid system. Subcellular localization assays showed that BcAtg3 diffused in cytoplasm, and BcAtg7 localized in cytoplasm as pre-autophagosomal structures (PAS). Target gene deletion experiments revealed that both BcATG3 and BcATG7 are essential for autophagy pathway. Notably, the single deletion mutant of BcATG3 and BcATG7 displayed similar biological phenotypes, including the defects in mycelial growth, conidiation and sclerotial formation. Infection tests showed that both BcATG3 and BcATG7 were required for full virulence of B. cinerea. All of these defective phenotypes were rescued by gene complementation. These results indicate that BcATG3 and BcATG7 are necessary for autophagy to regulate fungal development and pathogenesis in B. cinerea.
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Affiliation(s)
- Weichao Ren
- College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, Jiangsu, China
| | - Chengwei Sang
- College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, Jiangsu, China
| | - Dongya Shi
- College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, Jiangsu, China
| | - Xiushi Song
- College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, Jiangsu, China
| | - Mingguo Zhou
- College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, Jiangsu, China
| | - Changjun Chen
- College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, Jiangsu, China.
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8
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Wang R, Dong L, He R, Wang Q, Chen Y, Qu L, Zhang YA. Comparative genomic analyses reveal the features for adaptation to nematodes in fungi. DNA Res 2018; 25:4791394. [PMID: 29315395 PMCID: PMC6014366 DOI: 10.1093/dnares/dsx053] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 12/06/2017] [Indexed: 12/20/2022] Open
Abstract
Nematophagous (NP) fungi are ecologically important components of the soil microbiome in natural ecosystems. Esteya vermicola (Ev) has been reported as a NP fungus with a poorly understood evolutionary history and mechanism of adaptation to parasitism. Furthermore, NP fungal genomic basis of lifestyle was still unclear. We sequenced and annotated the Ev genome (34.2 Mbp) and integrated genetic makeup and evolution of pathogenic genes to investigate NP fungi. The results revealed that NP fungi had some abundant pathogenic genes corresponding to their niche. A number of gene families involved in pathogenicity were expanded, and some pathogenic orthologous genes underwent positive selection. NP fungi with diverse morphological features exhibit similarities of evolutionary convergence in attacking nematodes, but their genetic makeup and microscopic mechanism are different. Endoparasitic NP fungi showed similarity in large number of transporters and secondary metabolite coding genes. Noteworthy, expanded families of transporters and endo-beta-glucanase implied great genetic potential of Ev in quickly perturbing nematode metabolism and parasitic behavior. These results facilitate our understanding of NP fungal genomic features for adaptation to nematodes and lay a solid theoretical foundation for further research and application.
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Affiliation(s)
- Ruizhen Wang
- The Key Laboratory of Forest Protection, State Forestry Administration of China, Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing 100091, China
- Institute of Botany, Beijing Botanical Garden, Beijing 100093, China
| | - Leiming Dong
- State Key Laboratory of Tree Genetics and Breeding, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China
| | - Ran He
- The Key Laboratory of Forest Protection, State Forestry Administration of China, Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing 100091, China
- Institute of Botany, Beijing Botanical Garden, Beijing 100093, China
| | - Qinghua Wang
- The Key Laboratory of Forest Protection, State Forestry Administration of China, Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing 100091, China
| | - Yuequ Chen
- The Key Laboratory of Forest Protection, State Forestry Administration of China, Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing 100091, China
- Forestry Resources Protection Institute, Jilin Provincial Academy of Forestry Sciences, Changchun 130031, China
| | - Liangjian Qu
- The Key Laboratory of Forest Protection, State Forestry Administration of China, Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing 100091, China
| | - Yong-An Zhang
- The Key Laboratory of Forest Protection, State Forestry Administration of China, Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing 100091, China
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Kretschmer M, Lambie S, Croll D, Kronstad JW. Acetate provokes mitochondrial stress and cell death in Ustilago maydis. Mol Microbiol 2018; 107:488-507. [PMID: 29235175 DOI: 10.1111/mmi.13894] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 12/06/2017] [Accepted: 12/08/2017] [Indexed: 12/30/2022]
Abstract
The fungal pathogen Ustilago maydis causes disease on maize by mating to establish an infectious filamentous cell type that invades the host and induces tumours. We previously found that β-oxidation mutants were defective in virulence and did not grow on acetate. Here, we demonstrate that acetate inhibits filamentation during mating and in response to oleic acid. We therefore examined the influence of different carbon sources by comparing the transcriptomes of cells grown on acetate, oleic acid or glucose, with expression changes for the fungus during tumour formation in planta. Guided by the transcriptional profiling, we found that acetate negatively influenced resistance to stress, promoted the formation of reactive oxygen species, triggered cell death in stationary phase and impaired virulence on maize. We also found that acetate induced mitochondrial stress by interfering with mitochondrial functions. Notably, the disruption of oxygen perception or inhibition of the electron transport chain also influenced filamentation and mating. Finally, we made use of the connections between acetate and β-oxidation to test metabolic inhibitors for an influence on growth and virulence. These experiments identified diclofenac as a potential inhibitor of virulence. Overall, these findings support the possibility of targeting mitochondrial metabolic functions to control fungal pathogens.
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Affiliation(s)
- Matthias Kretschmer
- Michael Smith Laboratories, Department of Microbiology and Immunology, and Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Scott Lambie
- Michael Smith Laboratories, Department of Microbiology and Immunology, and Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Daniel Croll
- Michael Smith Laboratories, Department of Microbiology and Immunology, and Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
- Laboratory of Evolutionary Genetics, Institute of Biology, University of Neuchâtel, CH-2000 Neuchâtel, Switzerland
| | - James W Kronstad
- Michael Smith Laboratories, Department of Microbiology and Immunology, and Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
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Ghosh S, Kanwar P, Jha G. Identification of candidate pathogenicity determinants of Rhizoctonia solani AG1-IA, which causes sheath blight disease in rice. Curr Genet 2017; 64:729-740. [PMID: 29196814 DOI: 10.1007/s00294-017-0791-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2017] [Revised: 11/24/2017] [Accepted: 11/27/2017] [Indexed: 01/04/2023]
Abstract
Sheath blight disease is one of the predominant diseases of rice and it is caused by the necrotrophic fungal pathogen Rhizoctonia solani. The mechanistic insight about its widespread success as a broad host range pathogen is limited. In this study, we endeavor to identify pathogenicity determinants of R. solani during infection process in rice. Through RNAseq analysis, we identified a total of 65 and 232 R. solani (strain BRS1) genes to be commonly upregulated in three different rice genotypes (PB1, Tetep, and TP309) at establishment and necrotrophic phase, respectively. The induction of genes encoding extracellular protease, ABC transporter, and transcription factors were notable during establishment phase. While during necrotrophic phase, several CAZymes, sugar transporters, cellular metabolism, and protein degradation-related genes were prominently induced. We have also identified few putative secreted effector encoding genes that were upregulated during pathogenesis. The qPCR analysis further validated the phase-specific expression dynamics of some selected putative effectors and pathogenicity-associated genes. Overall, the present study reports identification of key genes and processes that might be crucial for R. solani pathogenesis. The ability to effectively damage host cell wall and survive in hostile plant environment by managing oxidative stress, cytotoxic compounds, etc. is being proposed to be important for pathogenesis of R. solani in rice. The functional characterization of these genes would provide key insights about this important pathosystem and facilitate development of strategies to control this devastating disease.
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Affiliation(s)
- Srayan Ghosh
- Plant Microbe Interactions Laboratory, National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Poonam Kanwar
- Plant Microbe Interactions Laboratory, National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Gopaljee Jha
- Plant Microbe Interactions Laboratory, National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India.
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11
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Functional analysis of diacylglycerol O-acyl transferase 2 gene to decipher its role in virulence of Botrytis cinerea. Curr Genet 2017; 64:443-457. [PMID: 28940057 DOI: 10.1007/s00294-017-0752-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 08/28/2017] [Accepted: 09/12/2017] [Indexed: 01/21/2023]
Abstract
Gray mold disease inflicted by Botrytis cinerea is a serious menace responsible for significant economic loss worldwide. Due to its polyphagous nature, the pathogen has enthused inquisitiveness in researchers to unravel its complexity. Agrobacterium tumefaciens-mediated transformation was used to generate insertional mutants of Botrytis cinerea. A mutant (BCM-55) with disruption in a gene (BcDGAT2) that encodes for diacylglycerol O-acyl transferase 2 (DGAT2), showed enervated virulence on various hosts' tissues. Enzyme DGAT2 is crucial in the final step of synthesis of triacylglycerol (TAG) that plays an important role in homeostasis of membrane and cellular processes. However, the role of DGAT2 has never been reported in a phytopathogenic fungus. In this study, BCM-55 was characterized to ascertain the role of DGAT2 in virulence of B. cinerea. The insertional mutant was defective in spore production and lacked sclerotia formation as a consequence of lower accumulation of TAG. A significant delay in spore germination in BCM-55 was accompanied with a low penetration potential. Hyphae of the mutant formed swollen endings with considerable impairment in penetration. Deletion of BcDGAT2 also led to increased sensitivity towards cell wall and membrane-disturbing agents. Furthermore, BCM-55 was deficient in the production of oxalic acid and showed lower activity of a cell wall-degrading enzyme, polygalacturonase. The role of BcDGAT2 in virulence was further confirmed by targeted deletion and complementation of the gene. The results insinuate a crucial role of BcDGAT2 in penetration and consequently virulence of B. cinerea. The study provides novel insights into plant-pathogen interactions that can be exploited to develop suitable disease management strategies.
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12
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Toh-E A, Ohkusu M, Shimizu K, Takahashi-Nakaguchi A, Kawamoto S, Ishiwada N, Watanabe A, Kamei K. Putative orotate transporter of Cryptococcus neoformans, Oat1, is a member of the NCS1/PRT transporter super family and its loss causes attenuation of virulence. Curr Genet 2016; 63:697-707. [PMID: 28011993 DOI: 10.1007/s00294-016-0672-5] [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: 10/03/2016] [Revised: 12/05/2016] [Accepted: 12/08/2016] [Indexed: 12/01/2022]
Abstract
It is well known that 5-fluoroorotic acid (5-FOA)-resistant mutants isolated from wild-type Cryptococcus neoformans are exclusively either ura3 or ura5 mutants. Unexpectedly, many of the 5-FOA-resistant mutants isolated in our selective regime were Ura+. We identified CNM00460 as the gene responsible for these mutations. Cnm00460 belongs to the nucleobase cation symporter 1/purine-related transporter (NCS1/PRT) super family of fungal transporters, representative members of which are uracil transporter, uridine transporter and allantoin transporter of Saccharomyces cerevisiae. Since the CNM00460 gene turned out to be involved in utilization of orotic acid, most probably as transporter, we designated this gene Orotic Acid Transporter 1 (OAT1). This is the first report of orotic acid transporter in this family. C. neoformans has four members of the NCS1/PRT family, including Cnm00460, Cnm02550, Cnj00690, and Cnn02280. Since the cnm02550∆ strain showed resistance to 5-fluorouridine, we concluded that CNM02550 encodes uridine permease and designated it URidine Permease 1 (URP1). We found that oat1 mutants were sensitive to 5-FOA in the medium containing proline as nitrogen source. A mutation in the GAT1 gene, a positive transcriptional regulator of genes under the control of nitrogen metabolite repression, in the genetic background of oat1 conferred the phenotype of weak resistance to 5-FOA even in the medium using proline as nitrogen source. Thus, we proposed the existence of another orotic acid utilization system (tentatively designated OAT2) whose expression is under the control of nitrogen metabolite repression at least in part. We found that the OAT1 gene is necessary for full pathogenic activity of C. neoformans var. neoformans.
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Affiliation(s)
- Akio Toh-E
- Medical Mycology Research Center, Chiba University, 1-8-1 Inohana, Chiba, 260-8673, Japan.
| | - Misako Ohkusu
- Medical Mycology Research Center, Chiba University, 1-8-1 Inohana, Chiba, 260-8673, Japan
| | - Kiminori Shimizu
- Medical Mycology Research Center, Chiba University, 1-8-1 Inohana, Chiba, 260-8673, Japan
- Tokyo University of Science, 5-3-1 Sinjuku, Katsusika-ku, Tokyo, 125-0051, Japan
| | | | - Susumu Kawamoto
- Medical Mycology Research Center, Chiba University, 1-8-1 Inohana, Chiba, 260-8673, Japan
| | - Naruhiko Ishiwada
- Medical Mycology Research Center, Chiba University, 1-8-1 Inohana, Chiba, 260-8673, Japan
| | - Akira Watanabe
- Medical Mycology Research Center, Chiba University, 1-8-1 Inohana, Chiba, 260-8673, Japan
| | - Katsuhiko Kamei
- Medical Mycology Research Center, Chiba University, 1-8-1 Inohana, Chiba, 260-8673, Japan
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Abrahamian M, Ah-Fong AMV, Davis C, Andreeva K, Judelson HS. Gene Expression and Silencing Studies in Phytophthora infestans Reveal Infection-Specific Nutrient Transporters and a Role for the Nitrate Reductase Pathway in Plant Pathogenesis. PLoS Pathog 2016; 12:e1006097. [PMID: 27936244 PMCID: PMC5176271 DOI: 10.1371/journal.ppat.1006097] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 12/21/2016] [Accepted: 11/28/2016] [Indexed: 11/19/2022] Open
Abstract
To help learn how phytopathogens feed from their hosts, genes for nutrient transporters from the hemibiotrophic potato and tomato pest Phytophthora infestans were annotated. This identified 453 genes from 19 families. Comparisons with a necrotrophic oomycete, Pythium ultimum var. ultimum, and a hemibiotrophic fungus, Magnaporthe oryzae, revealed diversity in the size of some families although a similar fraction of genes encoded transporters. RNA-seq of infected potato tubers, tomato leaves, and several artificial media revealed that 56 and 207 transporters from P. infestans were significantly up- or down-regulated, respectively, during early infection timepoints of leaves or tubers versus media. About 17 were up-regulated >4-fold in both leaves and tubers compared to media and expressed primarily in the biotrophic stage. The transcription pattern of many genes was host-organ specific. For example, the mRNA level of a nitrate transporter (NRT) was about 100-fold higher during mid-infection in leaves, which are nitrate-rich, than in tubers and three types of artificial media, which are nitrate-poor. The NRT gene is physically linked with genes encoding nitrate reductase (NR) and nitrite reductase (NiR), which mobilize nitrate into ammonium and amino acids. All three genes were coregulated. For example, the three genes were expressed primarily at mid-stage infection timepoints in both potato and tomato leaves, but showed little expression in potato tubers. Transformants down-regulated for all three genes were generated by DNA-directed RNAi, with silencing spreading from the NR target to the flanking NRT and NiR genes. The silenced strains were nonpathogenic on leaves but colonized tubers. We propose that the nitrate assimilation genes play roles both in obtaining nitrogen for amino acid biosynthesis and protecting P. infestans from natural or fertilization-induced nitrate and nitrite toxicity. Little is known of how plant pathogens adapt to different growth conditions and host tissues. To understand the interaction between the filamentous eukaryotic microbe Phytophthora infestans and its potato and tomato hosts, we mined the genome for genes encoding proteins involved in nutrient uptake and measured their expression in leaves, tubers, and three artificial media. We observed dynamic changes between the growth conditions, and identified transporters expressed mainly in the biotrophic stage, leaves, tubers, or artificial media. When we blocked the expression of a nitrate transporter and two other genes involved in assimilating nitrate, we observed that those genes were required for successful colonization of nitrate-rich leaves but not nitrate-poor tissues, and that nitrate had become toxic to the silenced strains. We therefore hypothesize that the nitrate assimilation pathway may help the pathogen use inorganic nitrogen for nutrition and/or detoxify nitrate when its levels may become damaging.
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Affiliation(s)
- Melania Abrahamian
- Department of Plant Pathology and Microbiology, University of California, Riverside, California, United States of America
| | - Audrey M. V. Ah-Fong
- Department of Plant Pathology and Microbiology, University of California, Riverside, California, United States of America
| | - Carol Davis
- Department of Plant Pathology and Microbiology, University of California, Riverside, California, United States of America
| | - Kalina Andreeva
- Department of Plant Pathology and Microbiology, University of California, Riverside, California, United States of America
| | - Howard S. Judelson
- Department of Plant Pathology and Microbiology, University of California, Riverside, California, United States of America
- * E-mail:
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Daumann M, Golfier P, Knüppel N, Hahn M, Möhlmann T. Botrytis cinerea can import and utilize nucleosides in salvage and catabolism and BcENT functions as high affinity nucleoside transporter. Fungal Biol 2016; 120:904-916. [PMID: 27521624 DOI: 10.1016/j.funbio.2016.05.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 04/13/2016] [Accepted: 05/31/2016] [Indexed: 10/21/2022]
Abstract
Nucleotide de novo synthesis is an essential pathway in nearly all organisms. Transport processes as well as salvage and catabolism of nucleotides and pathway intermediates are required to balance nucleotide pools. We have analysed the genome of the fungal plant pathogen Botrytis cinerea for genes involved in nucleotide metabolism and found a complete set of genes necessary for purine and pyrimidine uptake and salvage based on homology of the gene products to corresponding proteins from Aspergillus nidulans. Candidate genes required for a complete purine catabolic sequence were identified in addition. These analyses were complemented by growth tests showing functional transport and salvage activity for pyrimidines. Growth of B. cinerea mycelium in nitrogen free medium could be restored by addition of purines, indicating the presence of a functional purine catabolism, whereas pyrimidines did not support growth. Bcin07g05490 (BcENT) was identified as sole member of the equilibrative nucleoside transporter (ENT) family. The protein synthesized in Saccharomyces cerevisiae revealed high affinity transport of adenosine (KM = 6.81 μM) and uridine (KM=9.04 μM). Furthermore, a BcENT knockout mutant was generated and tested in a range of growth and infection assays. These results provide detailed insight in the use of externally supplied nucleobases and nucleosides by B. cinerea.
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Affiliation(s)
- Manuel Daumann
- Pflanzenphysiologie, Fachbereich Biologie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Straße, D-67663 Kaiserslautern, Germany
| | - Philippe Golfier
- Pflanzenphysiologie, Fachbereich Biologie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Straße, D-67663 Kaiserslautern, Germany
| | - Nathalie Knüppel
- Phytopathologie, Fachbereich Biologie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Straße, D-67663 Kaiserslautern, Germany
| | - Matthias Hahn
- Phytopathologie, Fachbereich Biologie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Straße, D-67663 Kaiserslautern, Germany
| | - Torsten Möhlmann
- Pflanzenphysiologie, Fachbereich Biologie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Straße, D-67663 Kaiserslautern, Germany.
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Insight into different environmental niches adaptation and allergenicity from the Cladosporium sphaerospermum genome, a common human allergy-eliciting Dothideomycetes. Sci Rep 2016; 6:27008. [PMID: 27243961 PMCID: PMC4886633 DOI: 10.1038/srep27008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 05/10/2016] [Indexed: 11/09/2022] Open
Abstract
Cladosporium sphaerospermum, a dematiaceous saprophytic fungus commonly found in diverse environments, has been reported to cause allergy and other occasional diseases in humans. However, its basic biology and genetic information are largely unexplored. A clinical isolate C. sphaerospermum genome, UM 843, was re-sequenced and combined with previously generated sequences to form a model 26.89 Mb genome containing 9,652 predicted genes. Functional annotation on predicted genes suggests the ability of this fungus to degrade carbohydrate and protein complexes. Several putative peptidases responsible for lung tissue hydrolysis were identified. These genes shared high similarity with the Aspergillus peptidases. The UM 843 genome encodes a wide array of proteins involved in the biosynthesis of melanin, siderophores, cladosins and survival in high salinity environment. In addition, a total of 28 genes were predicted to be associated with allergy. Orthologous gene analysis together with 22 other Dothideomycetes showed genes uniquely present in UM 843 that encode four class 1 hydrophobins which may be allergens specific to Cladosporium. The mRNA of these hydrophobins were detected by RT-PCR. The genomic analysis of UM 843 contributes to the understanding of the biology and allergenicity of this widely-prevalent species.
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