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Brenes Guallar MA, Fokkens L, Rep M, Berke L, van Dam P. Fusarium oxysporum effector clustering version 2: An updated pipeline to infer host range. FRONTIERS IN PLANT SCIENCE 2022; 13:1012688. [PMID: 36340405 PMCID: PMC9627151 DOI: 10.3389/fpls.2022.1012688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Accepted: 09/26/2022] [Indexed: 06/16/2023]
Abstract
The fungus Fusarium oxysporum is infamous for its devastating effects on economically important crops worldwide. F. oxysporum isolates are grouped into formae speciales based on their ability to cause disease on different hosts. Assigning F. oxysporum strains to formae speciales using non-experimental procedures has proven to be challenging due to their genetic heterogeneity and polyphyletic nature. However, genetically diverse isolates of the same forma specialis encode similar repertoires of effectors, proteins that are secreted by the fungus and contribute to the establishment of compatibility with the host. Based on this observation, we previously designed the F. oxysporum Effector Clustering (FoEC) pipeline which is able to classify F. oxysporum strains by forma specialis based on hierarchical clustering of the presence of predicted putative effector sequences, solely using genome assemblies as input. Here we present the updated FoEC2 pipeline which is more user friendly, customizable and, due to multithreading, has improved scalability. It is designed as a Snakemake pipeline and incorporates a new interactive visualization app. We showcase FoEC2 by clustering 537 publicly available F. oxysporum genomes and further analysis of putative effector families as multiple sequence alignments. We confirm classification of isolates into formae speciales and are able to further identify their subtypes. The pipeline is available on github: https://github.com/pvdam3/FoEC2.
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Affiliation(s)
- Megan A. Brenes Guallar
- Bioinformatics and Software Development Team, Genetwister Technologies B.V., Wageningen, Netherlands
| | - Like Fokkens
- Laboratory of Phytopathology, Wageningen University, Wageningen, Netherlands
- Molecular Plant Pathology, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, Netherlands
| | - Martijn Rep
- Molecular Plant Pathology, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, Netherlands
| | - Lidija Berke
- Bioinformatics and Software Development Team, Genetwister Technologies B.V., Wageningen, Netherlands
| | - Peter van Dam
- Bioinformatics and Software Development Team, Genetwister Technologies B.V., Wageningen, Netherlands
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2
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Buijs VA, Groenewald JZ, Haridas S, LaButti KM, Lipzen A, Martin FM, Barry K, Grigoriev IV, Crous PW, Seidl MF. Enemy or ally: a genomic approach to elucidate the lifestyle of Phyllosticta citrichinaensis. G3 (BETHESDA, MD.) 2022; 12:jkac061. [PMID: 35311955 PMCID: PMC9073689 DOI: 10.1093/g3journal/jkac061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 03/02/2022] [Indexed: 11/14/2022]
Abstract
Members of the fungal genus Phyllosticta can colonize a variety of plant hosts, including several Citrus species such as Citrus sinensis (orange), Citrus limon (lemon), and Citrus maxima (pomelo). Some Phyllosticta species have the capacity to cause disease, such as Citrus Black Spot, while others have only been observed as endophytes. Thus far, genomic differences underlying lifestyle adaptations of Phyllosticta species have not yet been studied. Furthermore, the lifestyle of Phyllosticta citrichinaensis is ambiguous, as it has been described as a weak pathogen but Koch's postulates may not have been established and the presence of this species was never reported to cause any crop or economic losses. Here, we examined the genomic differences between pathogenic and endophytic Phyllosticta spp. colonizing Citrus and specifically aimed to elucidate the lifestyle of Phyllosticta citrichinaensis. We found several genomic differences between species of different lifestyles, including groups of genes that were only present in pathogens or endophytes. We also observed that species, based on their carbohydrate active enzymes, group independent of their phylogenetic association, and this clustering correlated with trophy prediction. Phyllosticta citrichinaensis shows an intermediate lifestyle, sharing genomic and phenotypic attributes of both pathogens and endophytes. We thus present the first genomic comparison of multiple citrus-colonizing pathogens and endophytes of the genus Phyllosticta, and therefore provide the basis for further comparative studies into the lifestyle adaptations within this genus.
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Affiliation(s)
- Valerie A Buijs
- Evolutionary Phytopathology, Westerdijk Fungal Biodiversity Institute, Utrecht 3584 CT, The Netherlands
- Department of Plant Sciences, Laboratory of Phytopathology, Wageningen University and Research, Wageningen 6708 PB, The Netherlands
| | - Johannes Z Groenewald
- Evolutionary Phytopathology, Westerdijk Fungal Biodiversity Institute, Utrecht 3584 CT, The Netherlands
| | - Sajeet Haridas
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Kurt M LaButti
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Anna Lipzen
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Francis M Martin
- Department of Biology, Institut National de la Recherche Agronomique, UMR INRA-Université de Lorraine “Interaction Arbres/Microorganismes”, Champenoux F-54280, France
| | - Kerrie Barry
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Igor V Grigoriev
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, CA 94720, USA
| | - Pedro W Crous
- Evolutionary Phytopathology, Westerdijk Fungal Biodiversity Institute, Utrecht 3584 CT, The Netherlands
- Department of Plant Sciences, Laboratory of Phytopathology, Wageningen University and Research, Wageningen 6708 PB, The Netherlands
| | - Michael F Seidl
- Theoretical Biology & Bioinformatics, Utrecht University, Utrecht 3584 CH, The Netherlands
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3
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Skiadas P, Klein J, Quiroz Monnens T, Elberse J, de Jonge R, Van den Ackerveken G, Seidl MF. Sexual reproduction contributes to the evolution of resistance breaking isolates of the spinach pathogen Peronospora effusa. Environ Microbiol 2022; 24:1622-1637. [PMID: 35191594 PMCID: PMC9304176 DOI: 10.1111/1462-2920.15944] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 02/11/2022] [Accepted: 02/14/2022] [Indexed: 11/28/2022]
Abstract
Peronospora effusa causes downy mildew, the economically most important disease of cultivated spinach worldwide. To date, 19 P. effusa races have been denominated based on their capacity to break spinach resistances, but their genetic diversity and the evolutionary processes that contribute to race emergence are unknown. Here, we performed the first systematic analysis of P. effusa races showing that those emerge by both asexual and sexual reproduction. Specifically, we studied the diversity of 26 P. effusa isolates from 16 denominated races based on mitochondrial and nuclear comparative genomics. Mitochondrial genomes based on long‐read sequencing coupled with diversity assessment based on short‐read sequencing uncovered two mitochondrial haplogroups, each with distinct genome organization. Nuclear genome‐wide comparisons of the 26 isolates revealed that 10 isolates from six races could clearly be divided into three asexually evolving groups, in concordance with their mitochondrial phylogeny. The remaining isolates showed signals of reticulated evolution and discordance between nuclear and mitochondrial phylogenies, suggesting that these evolved through sexual reproduction. Increased understanding of this pathogen's reproductive modes will provide the framework for future studies into the molecular mechanisms underlying race emergence and into the P. effusa‐spinach interaction, thus assisting in sustainable production of spinach through knowledge‐driven resistance breeding.
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Affiliation(s)
- Petros Skiadas
- Theoretical Biology and Bioinformatics, Utrecht University, Padualaan 8 3584, CH, Utrecht, The Netherlands.,Plant-Microbe Interactions, Utrecht University, Padualaan 8 3584 CH, Utrecht, The Netherlands
| | - Joël Klein
- Plant-Microbe Interactions, Utrecht University, Padualaan 8 3584 CH, Utrecht, The Netherlands
| | - Thomas Quiroz Monnens
- Plant-Microbe Interactions, Utrecht University, Padualaan 8 3584 CH, Utrecht, The Netherlands
| | - Joyce Elberse
- Plant-Microbe Interactions, Utrecht University, Padualaan 8 3584 CH, Utrecht, The Netherlands
| | - Ronnie de Jonge
- Plant-Microbe Interactions, Utrecht University, Padualaan 8 3584 CH, Utrecht, The Netherlands
| | | | - Michael F Seidl
- Theoretical Biology and Bioinformatics, Utrecht University, Padualaan 8 3584, CH, Utrecht, The Netherlands
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4
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Koseoglou E, van der Wolf JM, Visser RGF, Bai Y. Susceptibility reversed: modified plant susceptibility genes for resistance to bacteria. TRENDS IN PLANT SCIENCE 2022; 27:69-79. [PMID: 34400073 DOI: 10.1016/j.tplants.2021.07.018] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 07/20/2021] [Accepted: 07/24/2021] [Indexed: 05/26/2023]
Abstract
Plants have evolved complex defence mechanisms to avoid invasion of potential pathogens. Despite this, adapted pathogens deploy effector proteins to manipulate host susceptibility (S) genes, rendering plant defences ineffective. The identification and mutation of plant S genes exploited by bacterial pathogens are important for the generation of crops with durable and broad-spectrum resistance. Application of mutant S genes in the breeding of resistant crops is limited because of potential pleiotropy. New genome editing techniques open up new possibilities for the modification of S genes. In this review, we focus on S genes manipulated by bacteria and propose ways for their identification and precise modification. Finally, we propose that genes coding for transporter proteins represent a new group of S genes.
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Affiliation(s)
- Eleni Koseoglou
- Plant Breeding, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands
| | - Jan M van der Wolf
- Biointeractions & Plant Health, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands
| | - Richard G F Visser
- Plant Breeding, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands
| | - Yuling Bai
- Plant Breeding, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands.
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5
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Nabi A, Banoo A, Rasool RS, Dar MS, Mubashir SS, Masoodi KZ, Shah MD, Khan AA, Khan I, Padder BA. Optimizing the Agrobacterium tumifaciens mediated transformation conditions in Colletotrichum lindemuthianum: A step forward to unravel the functions of pathogenicity arsenals. Lett Appl Microbiol 2021; 75:293-307. [PMID: 34398478 DOI: 10.1111/lam.13552] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 08/04/2021] [Accepted: 08/05/2021] [Indexed: 11/28/2022]
Abstract
Colletotrichum lindemuthianum is a hemibiotrophic fungal pathogen that causes bean anthracnose and it is rated among the top 10 important diseases infecting beans. Currently our knowledge on molecular mechanisms underlying C. lindemuthianum pathogenesis is limited. About five pathogenicity genes have been identified in C. lindemuthianum using Restricted Enzyme Mediated Integration (REMI) and the transformation using Agroinfection has not been optimized. In this study, a series of experiments were conducted to optimize the key parameters affecting the Agrobacterium tumefaciens- mediated transformation (ATMT) for C. lindemuthianum. The transformation efficiency increased with increase in spore concentration and co-cultivation time. However, the optimum conditions that yielded significant number of transformants were 106 ml-1 spore concentration, co-cultivation time of 72 h, incubation at 25ºC and using a cellulose membrane filter for the co-cultivation. The optimized protocol resulted in establishment of large mutant library (2400). A few mutants were melanin deficient and a few were unable to produce conidia. To determine the altered pathogenicity, two new approaches such as detached leaf and twig techniques proved reliable and require fewer resources to screen the large mutant libraries in a short time. Among the 1200 transformants tested for virulence, 90% transformants were pathogenically similar to wild type (race 2047), 96 and 24 were reduced and impaired, respectively. The altered avirulent transformants can prove vital for understanding the missing link between growth and developmental stages of pathogen with virulence. This platform will help to develop strategies to determine the potential pathogenicity genes and to decipher molecular mechanisms of host-pathogen interactions in more detail.
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Affiliation(s)
- Aasiya Nabi
- Plant Virology and Molecular Plant Pathology Laboratory, Division of Plant Pathology, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, India, 190 025
| | - Aqleema Banoo
- Plant Virology and Molecular Plant Pathology Laboratory, Division of Plant Pathology, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, India, 190 025
| | - Rovidha S Rasool
- Plant Virology and Molecular Plant Pathology Laboratory, Division of Plant Pathology, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, India, 190 025
| | - M S Dar
- Plant Virology and Molecular Plant Pathology Laboratory, Division of Plant Pathology, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, India, 190 025
| | - Syed Shoaib Mubashir
- Plant Virology and Molecular Plant Pathology Laboratory, Division of Plant Pathology, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, India, 190 025
| | - Khalid Z Masoodi
- Division of Plant Biotechnology, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, India, 190 025
| | - M D Shah
- Plant Virology and Molecular Plant Pathology Laboratory, Division of Plant Pathology, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, India, 190 025
| | - Akhtar A Khan
- Division of Entomology, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, India, 190 025
| | - Imran Khan
- Division of Agricultural Statistics, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, India, 190 025
| | - Bilal A Padder
- Plant Virology and Molecular Plant Pathology Laboratory, Division of Plant Pathology, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, India, 190 025
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Chavarro‐Carrero EA, Vermeulen JP, E. Torres D, Usami T, Schouten HJ, Bai Y, Seidl MF, Thomma BPHJ. Comparative genomics reveals the in planta-secreted Verticillium dahliae Av2 effector protein recognized in tomato plants that carry the V2 resistance locus. Environ Microbiol 2021; 23:1941-1958. [PMID: 33078534 PMCID: PMC8246953 DOI: 10.1111/1462-2920.15288] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 10/16/2020] [Accepted: 10/18/2020] [Indexed: 12/12/2022]
Abstract
Plant pathogens secrete effector molecules during host invasion to promote colonization. However, some of these effectors become recognized by host receptors to mount a defence response and establish immunity. Recently, a novel resistance was identified in wild tomato, mediated by the single dominant V2 locus, to control strains of the soil-borne vascular wilt fungus Verticillium dahliae that belong to race 2. With comparative genomics of race 2 strains and resistance-breaking race 3 strains, we identified the avirulence effector that activates V2 resistance, termed Av2. We identified 277 kb of race 2-specific sequence comprising only two genes encoding predicted secreted proteins that are expressed during tomato colonization. Subsequent functional analysis based on genetic complementation into race 3 isolates and targeted deletion from the race 1 isolate JR2 and race 2 isolate TO22 confirmed that one of the two candidates encodes the avirulence effector Av2 that is recognized in V2 tomato plants. Two Av2 allelic variants were identified that encode Av2 variants that differ by a single acid. Thus far, a role in virulence could not be demonstrated for either of the two variants.
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Affiliation(s)
| | - Jasper P. Vermeulen
- Laboratory of PhytopathologyWageningen University and ResearchWageningen6708 PBThe Netherlands
- Laboratory of Plant BreedingWageningen University and ResearchWageningen6708 PBThe Netherlands
| | - David E. Torres
- Laboratory of PhytopathologyWageningen University and ResearchWageningen6708 PBThe Netherlands
- Theoretical Biology and Bioinformatics Group, Department of BiologyUtrecht UniversityUtrechtThe Netherlands
| | - Toshiyuki Usami
- Graduate School of HorticultureChiba UniversityMatsudo, Chiba271‐8510Japan
| | - Henk J. Schouten
- Laboratory of Plant BreedingWageningen University and ResearchWageningen6708 PBThe Netherlands
| | - Yuling Bai
- Laboratory of Plant BreedingWageningen University and ResearchWageningen6708 PBThe Netherlands
| | - Michael F. Seidl
- Laboratory of PhytopathologyWageningen University and ResearchWageningen6708 PBThe Netherlands
- Theoretical Biology and Bioinformatics Group, Department of BiologyUtrecht UniversityUtrechtThe Netherlands
| | - Bart P. H. J. Thomma
- Laboratory of PhytopathologyWageningen University and ResearchWageningen6708 PBThe Netherlands
- Cluster of Excellence on Plant Sciences (CEPLAS)University of Cologne, Botanical InstituteCologneGermany
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7
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Singh KP, Kumari P, Rai PK. Current Status of the Disease-Resistant Gene(s)/QTLs, and Strategies for Improvement in Brassica juncea. FRONTIERS IN PLANT SCIENCE 2021; 12:617405. [PMID: 33747001 PMCID: PMC7965955 DOI: 10.3389/fpls.2021.617405] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 02/08/2021] [Indexed: 05/15/2023]
Abstract
Brassica juncea is a major oilseed crop in tropical and subtropical countries, especially in south-east Asia like India, China, Bangladesh, and Pakistan. The widespread cultivation of genetically similar varieties tends to attract fungal pathogens which cause heavy yield losses in the absence of resistant sources. The conventional disease management techniques are often expensive, have limited efficacy, and cause additional harm to the environment. A substantial approach is to identify and use of resistance sources within the Brassica hosts and other non-hosts to ensure sustainable oilseed crop production. In the present review, we discuss six major fungal pathogens of B. juncea: Sclerotinia stem rot (Sclerotinia sclerotiorum), Alternaria blight (Alternaria brassicae), White rust (Albugo candida), Downy mildew (Hyaloperonospora parasitica), Powdery mildew (Erysiphe cruciferarum), and Blackleg (Leptoshaeria maculans). From discussing studies on pathogen prevalence in B. juncea, the review then focuses on highlighting the resistance sources and quantitative trait loci/gene identified so far from Brassicaceae and non-filial sources against these fungal pathogens. The problems in the identification of resistance sources for B. juncea concerning genome complexity in host subpopulation and pathotypes were addressed. Emphasis has been laid on more elaborate and coordinated research to identify and deploy R genes, robust techniques, and research materials. Examples of fully characterized genes conferring resistance have been discussed that can be transformed into B. juncea using advanced genomics tools. Lastly, effective strategies for B. juncea improvement through introgression of novel R genes, development of pre-breeding resistant lines, characterization of pathotypes, and defense-related secondary metabolites have been provided suggesting the plan for the development of resistant B. juncea.
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Affiliation(s)
- Kaushal Pratap Singh
- ICAR-Directorate of Rapeseed-Mustard Research, Bharatpur, India
- *Correspondence: Kaushal Pratap Singh,
| | - Preetesh Kumari
- Genetics Division, ICAR-Indian Agricultural Research Institute, New Delhi, India
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8
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Mukhi N, Gorenkin D, Banfield MJ. Exploring folds, evolution and host interactions: understanding effector structure/function in disease and immunity. THE NEW PHYTOLOGIST 2020; 227:326-333. [PMID: 32239533 DOI: 10.1111/nph.16563] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 03/02/2020] [Indexed: 06/11/2023]
Abstract
Over the past decade, tremendous progress has been made in plant pathology, broadening our understanding of how pathogens colonize their hosts. To manipulate host cell physiology and subvert plant immune responses, pathogens secrete an array of effector proteins. A co-evolutionary arms-race drives the pathogen to constantly reinvent its effector repertoire to undermine plant immunity. In turn, hosts develop novel immune receptors to maintain effector recognition and mount defences. Understanding how effectors promote disease and how they are perceived by the plant's defence network persist as major subjects in the study of plant-pathogen interactions. Here, we focus on recent advances (over roughly the last two years) in understanding structure/function relationships in effectors from bacteria and filamentous plant pathogens. Structure/function studies of bacterial effectors frequently uncover diverse catalytic activities, while structure-informed similarity searches have enabled cataloguing of filamentous pathogen effectors. We also suggest how such advances have informed the study of plant-pathogen interactions.
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Affiliation(s)
- Nitika Mukhi
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK
| | - Danylo Gorenkin
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK
| | - Mark J Banfield
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK
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9
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Mousavi-Derazmahalleh M, Chang S, Thomas G, Derbyshire M, Bayer PE, Edwards D, Nelson MN, Erskine W, Lopez-Ruiz FJ, Clements J, Hane JK. Prediction of pathogenicity genes involved in adaptation to a lupin host in the fungal pathogens Botrytis cinerea and Sclerotinia sclerotiorum via comparative genomics. BMC Genomics 2019; 20:385. [PMID: 31101009 PMCID: PMC6525431 DOI: 10.1186/s12864-019-5774-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Accepted: 05/03/2019] [Indexed: 01/13/2023] Open
Abstract
Background Narrow-leafed lupin is an emerging crop of significance in agriculture, livestock feed and human health food. However, its susceptibility to various diseases is a major obstacle towards increased adoption. Sclerotinia sclerotiorum and Botrytis cinerea – both necrotrophs with broad host-ranges - are reported among the top 10 lupin pathogens. Whole-genome sequencing and comparative genomics are useful tools to discover genes responsible for interactions between pathogens and their hosts. Results Genomes were assembled for one isolate of B. cinerea and two isolates of S. sclerotiorum, which were isolated from either narrow-leafed or pearl lupin species. Comparative genomics analysis between lupin-derived isolates and others isolated from alternate hosts was used to predict between 94 to 98 effector gene candidates from among their respective non-conserved gene contents. Conclusions Detection of minor differences between relatively recently-diverged isolates, originating from distinct regions and with hosts, may highlight novel or recent gene mutations and losses resulting from host adaptation in broad host-range fungal pathogens. Electronic supplementary material The online version of this article (10.1186/s12864-019-5774-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Mahsa Mousavi-Derazmahalleh
- UWA School of Agriculture and Environment, The University of Western Australia, 35 Stirling Highway, Crawley, WA, 6009, Australia
| | - Steven Chang
- Centre for Crop and Disease Management, School of Molecular and Life Sciences, Curtin University, Bentley, WA, 6102, Australia
| | - Geoff Thomas
- Department of Primary Industries and Regional Development, 3 Baron-Hay Court, South Perth, WA, 6151, Australia
| | - Mark Derbyshire
- Centre for Crop and Disease Management, School of Molecular and Life Sciences, Curtin University, Bentley, WA, 6102, Australia
| | - Phillip E Bayer
- School of Biological Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, WA, 6009, Australia.,UWA Institute of Agriculture, The University of Western Australia, 35 Stirling Highway, Crawley, WA, 6009, Australia
| | - David Edwards
- School of Biological Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, WA, 6009, Australia.,UWA Institute of Agriculture, The University of Western Australia, 35 Stirling Highway, Crawley, WA, 6009, Australia
| | - Matthew N Nelson
- UWA School of Agriculture and Environment, The University of Western Australia, 35 Stirling Highway, Crawley, WA, 6009, Australia.,UWA Institute of Agriculture, The University of Western Australia, 35 Stirling Highway, Crawley, WA, 6009, Australia.,Natural Capital and Plant Health, Royal Botanic Gardens Kew, Wakehurst Place, Ardingly, West Sussex, RH17 6TN, UK.,Current address: Agriculture and Food, Commonwealth Scientific and Industrial Research Organisation, Wembley, WA, 6913, Australia
| | - William Erskine
- UWA School of Agriculture and Environment, The University of Western Australia, 35 Stirling Highway, Crawley, WA, 6009, Australia.,UWA Institute of Agriculture, The University of Western Australia, 35 Stirling Highway, Crawley, WA, 6009, Australia
| | - Francisco J Lopez-Ruiz
- Centre for Crop and Disease Management, School of Molecular and Life Sciences, Curtin University, Bentley, WA, 6102, Australia
| | - Jon Clements
- Department of Primary Industries and Regional Development, 3 Baron-Hay Court, South Perth, WA, 6151, Australia
| | - James K Hane
- Centre for Crop and Disease Management, School of Molecular and Life Sciences, Curtin University, Bentley, WA, 6102, Australia. .,Curtin Institute for Computation, Curtin University, Bentley, WA, 6102, Australia.
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10
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Abstract
Genomics studies in potato and other plants have elucidated a large number of genes involved in a wide array of phenotypes. In particular, recent bioinformatic and genomic analyses of oomycetes and fungi have identified many effectors for which the corresponding host resistance-eliciting receptor remains to be found. Functional testing of host resistance gene candidates can be accomplished by generating whole plant transformants to either overexpress or silence these genes to obtain a visible phenotype. However, this is time consuming. Alternatively, Agrobacterium tumefaciens can be used to transiently express genes in plant tissue to observe phenotypic changes. Wild relatives of potato contain a large amount of genotypic diversity and are an excellent tool to identify important agronomic traits, including resistance to diseases. The methods presented here help to facilitate the screening of wild potato accessions using agroinfiltration.
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11
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Yao J, Yu D, Cheng Y, Kang Z. Histological and cytological studies of plant infection by Erysiphe euonymi-japonici. PROTOPLASMA 2018; 255:1613-1620. [PMID: 29696381 DOI: 10.1007/s00709-018-1254-9] [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: 01/26/2018] [Accepted: 04/16/2018] [Indexed: 06/08/2023]
Abstract
Powdery mildew caused by Erysiphe euonymi-japonici (Eej) is an increasingly serious fungal disease on Euonymus japonicus that is an important ornamental plant. However, little is currently known about infection and pathogenesis of Eej on E. japonicus. Here, we report plant infection by Eej at the histological and cytological levels. Eej caused severe disease symptoms with white and snow-like colonies on leaf surfaces of E. japonicus. Microscopic observations were conducted continuously to define infection process of Eej on E. japonicus. Eej conidia germinated to produce appressorial germ tubes on leaf surfaces and formed irregular haustoria in plant epidermal cells at 6 h post-inoculation (hpi) and 12 hpi, respectively. After uptaking nutrients from host cells by haustoria, Eej formed numerous hyphae and extensive colonization on leaf surfaces at 96 hpi and finally produced abundant conidiophores and new conidia on leaf surfaces at 168 hpi. In addition, there was consistently a single nucleus in different Eej infection structures and haustorial development could be divided into three major stages, including formation of penetration peg, formation of haustorial neck and initial haustorium, and maturation of haustorium. These results provide useful information for further determination of Eej pathogenesis and finally controlling the disease.
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Affiliation(s)
- Juanni Yao
- State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, 712100, Shaanxi, China
- School of Life Sciences, Chongqing University, Chongqing, China
| | - Dan Yu
- State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Yulin Cheng
- State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, 712100, Shaanxi, China.
- School of Life Sciences, Chongqing University, Chongqing, China.
| | - Zhensheng Kang
- State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, 712100, Shaanxi, China.
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12
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Sánchez-Vallet A, Fouché S, Fudal I, Hartmann FE, Soyer JL, Tellier A, Croll D. The Genome Biology of Effector Gene Evolution in Filamentous Plant Pathogens. ANNUAL REVIEW OF PHYTOPATHOLOGY 2018; 56:21-40. [PMID: 29768136 DOI: 10.1146/annurev-phyto-080516-035303] [Citation(s) in RCA: 103] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Filamentous pathogens, including fungi and oomycetes, pose major threats to global food security. Crop pathogens cause damage by secreting effectors that manipulate the host to the pathogen's advantage. Genes encoding such effectors are among the most rapidly evolving genes in pathogen genomes. Here, we review how the major characteristics of the emergence, function, and regulation of effector genes are tightly linked to the genomic compartments where these genes are located in pathogen genomes. The presence of repetitive elements in these compartments is associated with elevated rates of point mutations and sequence rearrangements with a major impact on effector diversification. The expression of many effectors converges on an epigenetic control mediated by the presence of repetitive elements. Population genomics analyses showed that rapidly evolving pathogens show high rates of turnover at effector loci and display a mosaic in effector presence-absence polymorphism among strains. We conclude that effective pathogen containment strategies require a thorough understanding of the effector genome biology and the pathogen's potential for rapid adaptation.
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Affiliation(s)
- Andrea Sánchez-Vallet
- Plant Pathology, Institute of Integrative Biology, ETH Zürich, 8092 Zürich, Switzerland
| | - Simone Fouché
- Plant Pathology, Institute of Integrative Biology, ETH Zürich, 8092 Zürich, Switzerland
| | - Isabelle Fudal
- UMR BIOGER, INRA, AgroParisTech, Université Paris-Saclay, 78850 Thiverval-Grignon, France
| | - Fanny E Hartmann
- Ecologie Systématique Evolution, AgroParisTech, Université Paris-Sud, CNRS, Université Paris-Saclay, 91400 Orsay, France
| | - Jessica L Soyer
- UMR BIOGER, INRA, AgroParisTech, Université Paris-Saclay, 78850 Thiverval-Grignon, France
| | - Aurélien Tellier
- Section of Population Genetics, Technical University of Munich, 85354 Freising, Germany
| | - Daniel Croll
- Laboratory of Evolutionary Genetics, Institute of Biology, University of Neuchâtel, 2000 Neuchâtel, Switzerland;
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13
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Marton K, Flajšman M, Radišek S, Košmelj K, Jakše J, Javornik B, Berne S. Comprehensive analysis of Verticillium nonalfalfae in silico secretome uncovers putative effector proteins expressed during hop invasion. PLoS One 2018; 13:e0198971. [PMID: 29894496 PMCID: PMC5997321 DOI: 10.1371/journal.pone.0198971] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 05/28/2018] [Indexed: 12/22/2022] Open
Abstract
The vascular plant pathogen Verticillium nonalfalfae causes Verticillium wilt in several important crops. VnaSSP4.2 was recently discovered as a V. nonalfalfae virulence effector protein in the xylem sap of infected hop. Here, we expanded our search for candidate secreted effector proteins (CSEPs) in the V. nonalfalfae predicted secretome using a bioinformatic pipeline built on V. nonalfalfae genome data, RNA-Seq and proteomic studies of the interaction with hop. The secretome, rich in carbohydrate active enzymes, proteases, redox proteins and proteins involved in secondary metabolism, cellular processing and signaling, includes 263 CSEPs. Several homologs of known fungal effectors (LysM, NLPs, Hce2, Cerato-platanins, Cyanovirin-N lectins, hydrophobins and CFEM domain containing proteins) and avirulence determinants in the PHI database (Avr-Pita1 and MgSM1) were found. The majority of CSEPs were non-annotated and were narrowed down to 44 top priority candidates based on their likelihood of being effectors. These were examined by spatio-temporal gene expression profiling of infected hop. Among the highest in planta expressed CSEPs, five deletion mutants were tested in pathogenicity assays. A deletion mutant of VnaUn.279, a lethal pathotype specific gene with sequence similarity to SAM-dependent methyltransferase (LaeA), had lower infectivity and showed highly reduced virulence, but no changes in morphology, fungal growth or conidiation were observed. Several putative secreted effector proteins that probably contribute to V. nonalfalfae colonization of hop were identified in this study. Among them, LaeA gene homolog was found to act as a potential novel virulence effector of V. nonalfalfae. The combined results will serve for future characterization of V. nonalfalfae effectors, which will advance our understanding of Verticillium wilt disease.
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Affiliation(s)
- Kristina Marton
- Department of Agronomy, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Marko Flajšman
- Department of Agronomy, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | | | - Katarina Košmelj
- Department of Agronomy, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Jernej Jakše
- Department of Agronomy, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Branka Javornik
- Department of Agronomy, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Sabina Berne
- Department of Agronomy, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
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14
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Sahebi M, Hanafi MM, van Wijnen AJ, Rice D, Rafii MY, Azizi P, Osman M, Taheri S, Bakar MFA, Isa MNM, Noor YM. Contribution of transposable elements in the plant's genome. Gene 2018; 665:155-166. [PMID: 29684486 DOI: 10.1016/j.gene.2018.04.050] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 04/04/2018] [Accepted: 04/18/2018] [Indexed: 12/26/2022]
Abstract
Plants maintain extensive growth flexibility under different environmental conditions, allowing them to continuously and rapidly adapt to alterations in their environment. A large portion of many plant genomes consists of transposable elements (TEs) that create new genetic variations within plant species. Different types of mutations may be created by TEs in plants. Many TEs can avoid the host's defense mechanisms and survive alterations in transposition activity, internal sequence and target site. Thus, plant genomes are expected to utilize a variety of mechanisms to tolerate TEs that are near or within genes. TEs affect the expression of not only nearby genes but also unlinked inserted genes. TEs can create new promoters, leading to novel expression patterns or alternative coding regions to generate alternate transcripts in plant species. TEs can also provide novel cis-acting regulatory elements that act as enhancers or inserts within original enhancers that are required for transcription. Thus, the regulation of plant gene expression is strongly managed by the insertion of TEs into nearby genes. TEs can also lead to chromatin modifications and thereby affect gene expression in plants. TEs are able to generate new genes and modify existing gene structures by duplicating, mobilizing and recombining gene fragments. They can also facilitate cellular functions by sharing their transposase-coding regions. Hence, TE insertions can not only act as simple mutagens but can also alter the elementary functions of the plant genome. Here, we review recent discoveries concerning the contribution of TEs to gene expression in plant genomes and discuss the different mechanisms by which TEs can affect plant gene expression and reduce host defense mechanisms.
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Affiliation(s)
- Mahbod Sahebi
- Laboratory of Climate-Smart Food Crop Production, Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
| | - Mohamed M Hanafi
- Laboratory of Climate-Smart Food Crop Production, Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia; Laboratory of Plantation Science and Technology, Institute of Plantation Studies, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia; Department of Land Management, Faculty of Agriculture, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
| | | | - David Rice
- Department of Molecular Biology & Biotecnology, University of Sheffield, United Kingdom
| | - M Y Rafii
- Laboratory of Climate-Smart Food Crop Production, Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Parisa Azizi
- Department of Crop Science, Faculty of Agriculture, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Mohamad Osman
- Department of Crop Science, Faculty of Agriculture, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Sima Taheri
- Department of Crop Science, Faculty of Agriculture, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
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15
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Fouché S, Plissonneau C, Croll D. The birth and death of effectors in rapidly evolving filamentous pathogen genomes. Curr Opin Microbiol 2018; 46:34-42. [PMID: 29455143 DOI: 10.1016/j.mib.2018.01.020] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 01/15/2018] [Accepted: 01/31/2018] [Indexed: 11/19/2022]
Abstract
Plant pathogenic fungi and oomycetes are major risks to food security due to their evolutionary success in overcoming plant defences. Pathogens produce effectors to interfere with host defences and metabolism. These effectors are often encoded in rapidly evolving compartments of the genome. We review how effector genes emerged and were lost in pathogen genomes drawing on the links between effector evolution and chromosomal rearrangements. Some new effectors entered pathogen genomes via horizontal transfer or introgression. However, new effector functions also arose through gene duplication or from previously non-coding sequences. The evolutionary success of an effector is tightly linked to its transcriptional regulation during host colonization. Some effectors converged on an epigenetic control of expression imposed by genomic defences against transposable elements. Transposable elements were also drivers of effector diversification and loss that led to mosaics in effector presence-absence variation. Such effector mosaics within species was the foundation for rapid pathogen adaptation.
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Affiliation(s)
- Simone Fouché
- Plant Pathology, Institute of Integrative Biology, ETH Zurich, 8092 Zurich, Switzerland
| | - Clémence Plissonneau
- Plant Pathology, Institute of Integrative Biology, ETH Zurich, 8092 Zurich, Switzerland; UMR BIOGER, INRA, AgroParisTech, Université Paris-Saclay, Avenue Lucien Bretignières, BP 01, Thiverval-Grignon F-78850, France
| | - Daniel Croll
- Laboratory of Evolutionary Genetics, Institute of Biology, University of Neuchâtel, CH-2000 Neuchâtel, Switzerland.
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16
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Richards JK, Wyatt NA, Liu Z, Faris JD, Friesen TL. Reference Quality Genome Assemblies of Three Parastagonospora nodorum Isolates Differing in Virulence on Wheat. G3 (BETHESDA, MD.) 2018; 8:393-399. [PMID: 29233913 PMCID: PMC5919747 DOI: 10.1534/g3.117.300462] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 12/07/2017] [Indexed: 01/01/2023]
Abstract
Parastagonospora nodorum, the causal agent of Septoria nodorum blotch in wheat, has emerged as a model necrotrophic fungal organism for the study of host-microbe interactions. To date, three necrotrophic effectors have been identified and characterized from this pathogen, including SnToxA, SnTox1, and SnTox3. Necrotrophic effector identification was greatly aided by the development of a draft genome of Australian isolate SN15 via Sanger sequencing, yet it remained largely fragmented. This research presents the development of nearly finished genomes of P. nodorum isolates Sn4, Sn2000, and Sn79-1087 using long-read sequencing technology. RNAseq analysis of isolate Sn4, consisting of eight time points covering various developmental and infection stages, mediated the annotation of 13,379 genes. Analysis of these genomes revealed large-scale polymorphism between the three isolates, including the complete absence of contig 23 from isolate Sn79-1087, and a region of genome expansion on contig 10 in isolates Sn4 and Sn2000. Additionally, these genomes exhibit the hallmark characteristics of a "two-speed" genome, being partitioned into two distinct GC-equilibrated and AT-rich compartments. Interestingly, isolate Sn79-1087 contains a lower proportion of AT-rich segments, indicating a potential lack of evolutionary hotspots. These newly sequenced genomes, consisting of telomere-to-telomere assemblies of nearly all 23 P. nodorum chromosomes, provide a robust foundation for the further examination of effector biology and genome evolution.
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Affiliation(s)
- Jonathan K Richards
- Department of Plant Pathology, North Dakota State University, Fargo, North Dakota 58102
| | - Nathan A Wyatt
- Genomics and Bioinformatics Program, North Dakota State University, Fargo, North Dakota 58102
| | - Zhaohui Liu
- Department of Plant Pathology, North Dakota State University, Fargo, North Dakota 58102
| | - Justin D Faris
- Genomics and Bioinformatics Program, North Dakota State University, Fargo, North Dakota 58102
- Cereal Crops Research Unit, Red River Valley Agricultural Research Center, United States Department of Agriculture-Agricultural Research Service (USDA-ARS), Fargo, North Dakota 58102
| | - Timothy L Friesen
- Department of Plant Pathology, North Dakota State University, Fargo, North Dakota 58102
- Genomics and Bioinformatics Program, North Dakota State University, Fargo, North Dakota 58102
- Cereal Crops Research Unit, Red River Valley Agricultural Research Center, United States Department of Agriculture-Agricultural Research Service (USDA-ARS), Fargo, North Dakota 58102
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17
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Stewart EL, Croll D, Lendenmann MH, Sanchez‐Vallet A, Hartmann FE, Palma‐Guerrero J, Ma X, McDonald BA. Quantitative trait locus mapping reveals complex genetic architecture of quantitative virulence in the wheat pathogen Zymoseptoria tritici. MOLECULAR PLANT PATHOLOGY 2018; 19:201-216. [PMID: 27868326 PMCID: PMC6638037 DOI: 10.1111/mpp.12515] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
We conducted a comprehensive analysis of virulence in the fungal wheat pathogen Zymoseptoria tritici using quantitative trait locus (QTL) mapping. High-throughput phenotyping based on automated image analysis allowed the measurement of pathogen virulence on a scale and with a precision that was not previously possible. Across two mapping populations encompassing more than 520 progeny, 540 710 pycnidia were counted and their sizes and grey values were measured. A significant correlation was found between pycnidia size and both spore size and number. Precise measurements of percentage leaf area covered by lesions provided a quantitative measure of host damage. Combining these large and accurate phenotypic datasets with a dense panel of restriction site-associated DNA sequencing (RADseq) genetic markers enabled us to genetically dissect pathogen virulence into components related to host damage and those related to pathogen reproduction. We showed that different components of virulence can be under separate genetic control. Large- and small-effect QTLs were identified for all traits, with some QTLs specific to mapping populations, cultivars and traits and other QTLs shared among traits within the same mapping population. We associated the presence of four accessory chromosomes with small, but significant, increases in several virulence traits, providing the first evidence for a meaningful function associated with accessory chromosomes in this organism. A large-effect QTL involved in host specialization was identified on chromosome 7, leading to the identification of candidate genes having a large effect on virulence.
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Affiliation(s)
- Ethan l. Stewart
- Plant Pathology Group, ETH Zürich, Universitätstrasse 2Zürich8092Switzerland
| | - Daniel Croll
- Plant Pathology Group, ETH Zürich, Universitätstrasse 2Zürich8092Switzerland
| | - Mark H. Lendenmann
- Plant Pathology Group, ETH Zürich, Universitätstrasse 2Zürich8092Switzerland
| | | | - Fanny E. Hartmann
- Plant Pathology Group, ETH Zürich, Universitätstrasse 2Zürich8092Switzerland
| | | | - Xin Ma
- Plant Pathology Group, ETH Zürich, Universitätstrasse 2Zürich8092Switzerland
| | - Bruce A. McDonald
- Plant Pathology Group, ETH Zürich, Universitätstrasse 2Zürich8092Switzerland
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18
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Neik TX, Barbetti MJ, Batley J. Current Status and Challenges in Identifying Disease Resistance Genes in Brassica napus. FRONTIERS IN PLANT SCIENCE 2017; 8:1788. [PMID: 29163558 PMCID: PMC5681527 DOI: 10.3389/fpls.2017.01788] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 10/02/2017] [Indexed: 05/18/2023]
Abstract
Brassica napus is an economically important crop across different continents including temperate and subtropical regions in Europe, Canada, South Asia, China and Australia. Its widespread cultivation also brings setbacks as it plays host to fungal, oomycete and chytrid pathogens that can lead to serious yield loss. For sustainable crop production, identification of resistance (R) genes in B. napus has become of critical importance. In this review, we discuss four key pathogens affecting Brassica crops: Clubroot (Plasmodiophora brassicae), Blackleg (Leptosphaeria maculans and L. biglobosa), Sclerotinia Stem Rot (Sclerotinia sclerotiorum), and Downy Mildew (Hyaloperonospora parasitica). We first review current studies covering prevalence of these pathogens on Brassica crops and highlight the R genes and QTL that have been identified from Brassica species against these pathogens. Insights into the relationships between the pathogen and its Brassica host, the unique host resistance mechanisms and how these affect resistance outcomes is also presented. We discuss challenges in identification and deployment of R genes in B. napus in relation to highly specific genetic interactions between host subpopulations and pathogen pathotypes and emphasize the need for common or shared techniques and research materials or tighter collaboration between researchers to reconcile the inconsistencies in the research outcomes. Using current genomics tools, we provide examples of how characterization and cloning of R genes in B. napus can be carried out more effectively. Lastly, we put forward strategies to breed resistant cultivars through introgressions supported by genomic approaches and suggest prospects that can be implemented in the future for a better, pathogen-resistant B. napus.
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Affiliation(s)
- Ting Xiang Neik
- School of Biological Sciences, University of Western Australia, Perth, WA, Australia
| | - Martin J. Barbetti
- School of Agriculture and Environment and Institute of Agriculture, University of Western Australia, Perth, WA, Australia
| | - Jacqueline Batley
- School of Biological Sciences, University of Western Australia, Perth, WA, Australia
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19
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Seidl MF, Thomma BPHJ. Transposable Elements Direct The Coevolution between Plants and Microbes. Trends Genet 2017; 33:842-851. [PMID: 28800915 DOI: 10.1016/j.tig.2017.07.003] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 06/24/2017] [Accepted: 07/14/2017] [Indexed: 12/31/2022]
Abstract
Transposable elements are powerful drivers of genome evolution in many eukaryotes. Although they are mostly considered as 'selfish' genetic elements, increasing evidence suggests that they contribute to genetic variability; particularly under stress conditions. Over the past few years, the role of transposable elements during host-microbe interactions has been recognised. It has been proposed that many pathogenic microbes have evolved a 'two-speed' genome with regions that show increased variability and that are enriched in transposable elements and pathogenicity-related genes. Plants similarly display structured genomes with transposable-element-rich regions that mediate accelerated evolution. Immune receptor genes typically reside in such regions. Various mechanisms have recently been identified through which transposable elements contribute to the coevolution between plants and their associated microbes.
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Affiliation(s)
- Michael F Seidl
- Laboratory of Phytopathology, Wageningen University and Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands; Both authors contributed equally.
| | - Bart P H J Thomma
- Laboratory of Phytopathology, Wageningen University and Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands; Both authors contributed equally.
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20
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Kombrink A, Rovenich H, Shi‐Kunne X, Rojas‐Padilla E, van den Berg GCM, Domazakis E, de Jonge R, Valkenburg D, Sánchez‐Vallet A, Seidl MF, Thomma BPHJ. Verticillium dahliae LysM effectors differentially contribute to virulence on plant hosts. MOLECULAR PLANT PATHOLOGY 2017; 18:596-608. [PMID: 27911046 PMCID: PMC6638240 DOI: 10.1111/mpp.12520] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Chitin-binding lysin motif (LysM) effectors contribute to the virulence of various plant-pathogenic fungi that are causal agents of foliar diseases. Here, we report the LysM effectors of the soil-borne fungal vascular wilt pathogen Verticillium dahliae. Comparative genomics revealed three core LysM effectors that are conserved in a collection of V. dahliae strains. Remarkably, and in contrast with the previously studied LysM effectors of other plant pathogens, no expression of core LysM effectors was monitored in planta in a taxonomically diverse panel of host plants. Moreover, targeted deletion of the individual LysM effector genes in V. dahliae strain JR2 did not compromise virulence in infections on Arabidopsis, tomato or Nicotiana benthamiana. Interestingly, an additional lineage-specific LysM effector is encoded in the genome of V. dahliae strain VdLs17, but not in any other V. dahliae strain sequenced to date. Remarkably, this lineage-specific effector is expressed in planta and contributes to the virulence of V. dahliae strain VdLs17 on tomato, but not on Arabidopsis or N. benthamiana. Functional analysis revealed that this LysM effector binds chitin, is able to suppress chitin-induced immune responses and protects fungal hyphae against hydrolysis by plant hydrolytic enzymes. Thus, in contrast with the core LysM effectors of V. dahliae, this lineage-specific LysM effector of strain VdLs17 contributes to virulence in planta.
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Affiliation(s)
- Anja Kombrink
- Laboratory of PhytopathologyWageningen UniversityDroevendaalsesteeg 1WageningenPB 6708the Netherlands
| | - Hanna Rovenich
- Laboratory of PhytopathologyWageningen UniversityDroevendaalsesteeg 1WageningenPB 6708the Netherlands
| | - Xiaoqian Shi‐Kunne
- Laboratory of PhytopathologyWageningen UniversityDroevendaalsesteeg 1WageningenPB 6708the Netherlands
| | - Eduardo Rojas‐Padilla
- Laboratory of PhytopathologyWageningen UniversityDroevendaalsesteeg 1WageningenPB 6708the Netherlands
| | - Grardy C. M. van den Berg
- Laboratory of PhytopathologyWageningen UniversityDroevendaalsesteeg 1WageningenPB 6708the Netherlands
| | - Emmanouil Domazakis
- Laboratory of PhytopathologyWageningen UniversityDroevendaalsesteeg 1WageningenPB 6708the Netherlands
| | - Ronnie de Jonge
- Laboratory of PhytopathologyWageningen UniversityDroevendaalsesteeg 1WageningenPB 6708the Netherlands
| | - Dirk‐Jan Valkenburg
- Laboratory of PhytopathologyWageningen UniversityDroevendaalsesteeg 1WageningenPB 6708the Netherlands
| | - Andrea Sánchez‐Vallet
- Laboratory of PhytopathologyWageningen UniversityDroevendaalsesteeg 1WageningenPB 6708the Netherlands
| | - Michael F. Seidl
- Laboratory of PhytopathologyWageningen UniversityDroevendaalsesteeg 1WageningenPB 6708the Netherlands
| | - Bart P. H. J. Thomma
- Laboratory of PhytopathologyWageningen UniversityDroevendaalsesteeg 1WageningenPB 6708the Netherlands
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21
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Plissonneau C, Benevenuto J, Mohd-Assaad N, Fouché S, Hartmann FE, Croll D. Using Population and Comparative Genomics to Understand the Genetic Basis of Effector-Driven Fungal Pathogen Evolution. FRONTIERS IN PLANT SCIENCE 2017; 8:119. [PMID: 28217138 PMCID: PMC5289978 DOI: 10.3389/fpls.2017.00119] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 01/20/2017] [Indexed: 05/20/2023]
Abstract
Epidemics caused by fungal plant pathogens pose a major threat to agro-ecosystems and impact global food security. High-throughput sequencing enabled major advances in understanding how pathogens cause disease on crops. Hundreds of fungal genomes are now available and analyzing these genomes highlighted the key role of effector genes in disease. Effectors are small secreted proteins that enhance infection by manipulating host metabolism. Fungal genomes carry 100s of putative effector genes, but the lack of homology among effector genes, even for closely related species, challenges evolutionary and functional analyses. Furthermore, effector genes are often found in rapidly evolving chromosome compartments which are difficult to assemble. We review how population and comparative genomics toolsets can be combined to address these challenges. We highlight studies that associated genome-scale polymorphisms with pathogen lifestyles and adaptation to different environments. We show how genome-wide association studies can be used to identify effectors and other pathogenicity-related genes underlying rapid adaptation. We also discuss how the compartmentalization of fungal genomes into core and accessory regions shapes the evolution of effector genes. We argue that an understanding of genome evolution provides important insight into the trajectory of host-pathogen co-evolution.
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Affiliation(s)
- Clémence Plissonneau
- Plant Pathology, Institute of Integrative Biology, ETH ZurichZurich, Switzerland
- UMR, BIOGER, INRA, AgroParisTech, Université Paris-SaclayThiverval-Grignon, France
| | - Juliana Benevenuto
- College of Agriculture “Luiz de Queiroz”, University of São PauloSão Paulo, Brazil
| | - Norfarhan Mohd-Assaad
- Plant Pathology, Institute of Integrative Biology, ETH ZurichZurich, Switzerland
- School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan MalaysiaSelangor, Malaysia
| | - Simone Fouché
- Plant Pathology, Institute of Integrative Biology, ETH ZurichZurich, Switzerland
| | - Fanny E. Hartmann
- Plant Pathology, Institute of Integrative Biology, ETH ZurichZurich, Switzerland
| | - Daniel Croll
- Plant Pathology, Institute of Integrative Biology, ETH ZurichZurich, Switzerland
- Laboratory of Evolutionary Genetics, Institute of Biology, University of NeuchatelNeuchatel, Switzerland
- *Correspondence: Daniel Croll,
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22
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Klosterman SJ, Rollins JR, Sudarshana MR, Vinatzer BA. Disease Management in the Genomics Era-Summaries of Focus Issue Papers. PHYTOPATHOLOGY 2016; 106:1068-1070. [PMID: 27482626 DOI: 10.1094/phyto-07-16-0276-fi] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The genomics revolution has contributed enormously to research and disease management applications in plant pathology. This development has rapidly increased our understanding of the molecular mechanisms underpinning pathogenesis and resistance, contributed novel markers for rapid pathogen detection and diagnosis, and offered further insights into the genetics of pathogen populations on a larger scale. The availability of whole genome resources coupled with next-generation sequencing (NGS) technologies has helped fuel genomics-based approaches to improve disease resistance in crops. NGS technologies have accelerated the pace at which whole plant and pathogen genomes have become available, and made possible the metagenomic analysis of plant-associated microbial communities. Furthermore, NGS technologies can now be applied routinely and cost effectively to rapidly generate plant and/or pathogen genome or transcriptome marker sequences associated with virulence phenotypes in the pathogen or resistance phenotypes in the plant, potentially leading to improvements in plant disease management. In some systems, investments in plant and pathogen genomics have led to immediate, tangible benefits. This focus issue covers some of the systems. The articles in this focus issue range from overall perspective articles to research articles describing specific genomics applications for detection and control of diseases caused by nematode, viral, bacterial, fungal, and oomycete pathogens. The following are representative short summaries of the articles that appear in this Focus Issue .
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Affiliation(s)
- S J Klosterman
- 2016 Focus Issue Senior Editors First author: U.S. Department of Agriculture-Agriculture Research Service (USDA-ARS), 1636 E. Alisal Street, Salinas, CA 93905; second author: Department of Plant Pathology, University of Florida, Gainesville 32611; third author: USDA-ARS, One Shields Avenue, Davis, CA 95616; and fourth author: Department of Plant Pathology, Physiology, and Weed Science, Virginia Tech, Blacksburg 24061
| | - J R Rollins
- 2016 Focus Issue Senior Editors First author: U.S. Department of Agriculture-Agriculture Research Service (USDA-ARS), 1636 E. Alisal Street, Salinas, CA 93905; second author: Department of Plant Pathology, University of Florida, Gainesville 32611; third author: USDA-ARS, One Shields Avenue, Davis, CA 95616; and fourth author: Department of Plant Pathology, Physiology, and Weed Science, Virginia Tech, Blacksburg 24061
| | - M R Sudarshana
- 2016 Focus Issue Senior Editors First author: U.S. Department of Agriculture-Agriculture Research Service (USDA-ARS), 1636 E. Alisal Street, Salinas, CA 93905; second author: Department of Plant Pathology, University of Florida, Gainesville 32611; third author: USDA-ARS, One Shields Avenue, Davis, CA 95616; and fourth author: Department of Plant Pathology, Physiology, and Weed Science, Virginia Tech, Blacksburg 24061
| | - B A Vinatzer
- 2016 Focus Issue Senior Editors First author: U.S. Department of Agriculture-Agriculture Research Service (USDA-ARS), 1636 E. Alisal Street, Salinas, CA 93905; second author: Department of Plant Pathology, University of Florida, Gainesville 32611; third author: USDA-ARS, One Shields Avenue, Davis, CA 95616; and fourth author: Department of Plant Pathology, Physiology, and Weed Science, Virginia Tech, Blacksburg 24061
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