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Mesarich CH, Barnes I, Bradley EL, de la Rosa S, de Wit PJGM, Guo Y, Griffiths SA, Hamelin RC, Joosten MHAJ, Lu M, McCarthy HM, Schol CR, Stergiopoulos I, Tarallo M, Zaccaron AZ, Bradshaw RE. Beyond the genomes of Fulvia fulva (syn. Cladosporium fulvum) and Dothistroma septosporum: New insights into how these fungal pathogens interact with their host plants. MOLECULAR PLANT PATHOLOGY 2023; 24:474-494. [PMID: 36790136 PMCID: PMC10098069 DOI: 10.1111/mpp.13309] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 01/23/2023] [Accepted: 01/25/2023] [Indexed: 05/03/2023]
Abstract
Fulvia fulva and Dothistroma septosporum are closely related apoplastic pathogens with similar lifestyles but different hosts: F. fulva is a pathogen of tomato, whilst D. septosporum is a pathogen of pine trees. In 2012, the first genome sequences of these pathogens were published, with F. fulva and D. septosporum having highly fragmented and near-complete assemblies, respectively. Since then, significant advances have been made in unravelling their genome architectures. For instance, the genome of F. fulva has now been assembled into 14 chromosomes, 13 of which have synteny with the 14 chromosomes of D. septosporum, suggesting these pathogens are even more closely related than originally thought. Considerable advances have also been made in the identification and functional characterization of virulence factors (e.g., effector proteins and secondary metabolites) from these pathogens, thereby providing new insights into how they promote host colonization or activate plant defence responses. For example, it has now been established that effector proteins from both F. fulva and D. septosporum interact with cell-surface immune receptors and co-receptors to activate the plant immune system. Progress has also been made in understanding how F. fulva and D. septosporum have evolved with their host plants, whilst intensive research into pandemics of Dothistroma needle blight in the Northern Hemisphere has shed light on the origins, migration, and genetic diversity of the global D. septosporum population. In this review, we specifically summarize advances made in our understanding of the F. fulva-tomato and D. septosporum-pine pathosystems over the last 10 years.
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Affiliation(s)
- Carl H. Mesarich
- Laboratory of Molecular Plant Pathology, School of Agriculture and EnvironmentMassey UniversityPalmerston NorthNew Zealand
- Bioprotection AotearoaMassey UniversityPalmerston NorthNew Zealand
| | - Irene Barnes
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology InstituteUniversity of PretoriaPretoriaSouth Africa
| | - Ellie L. Bradley
- Laboratory of Molecular Plant Pathology, School of Agriculture and EnvironmentMassey UniversityPalmerston NorthNew Zealand
| | - Silvia de la Rosa
- Laboratory of Molecular Plant Pathology, School of Agriculture and EnvironmentMassey UniversityPalmerston NorthNew Zealand
| | | | - Yanan Guo
- Bioprotection AotearoaMassey UniversityPalmerston NorthNew Zealand
- Laboratory of Molecular Plant Pathology, School of Natural SciencesMassey UniversityPalmerston NorthNew Zealand
| | | | - Richard C. Hamelin
- Department of Forest and Conservation SciencesUniversity of British ColumbiaVancouverBritish ColumbiaCanada
- Institut de Biologie Intégrative et des SystèmesUniversité LavalQuébec CityQuébecCanada
| | | | - Mengmeng Lu
- Department of Biological SciencesUniversity of CalgaryCalgaryAlbertaCanada
| | - Hannah M. McCarthy
- Laboratory of Molecular Plant Pathology, School of Natural SciencesMassey UniversityPalmerston NorthNew Zealand
| | - Christiaan R. Schol
- Laboratory of PhytopathologyWageningen UniversityWageningenNetherlands
- Plant BreedingWageningen University & ResearchWageningenNetherlands
| | | | - Mariana Tarallo
- Laboratory of Molecular Plant Pathology, School of Natural SciencesMassey UniversityPalmerston NorthNew Zealand
| | - Alex Z. Zaccaron
- Department of Plant PathologyUniversity of California DavisDavisCaliforniaUSA
| | - Rosie E. Bradshaw
- Bioprotection AotearoaMassey UniversityPalmerston NorthNew Zealand
- Laboratory of Molecular Plant Pathology, School of Natural SciencesMassey UniversityPalmerston NorthNew Zealand
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van der Nest A, Wingfield MJ, Sadiković D, Mullett MS, Marçais B, Queloz V, Adamčíková K, Davydenko K, Barnes I. Population structure and diversity of the needle pathogen Dothistroma pini suggests human-mediated movement in Europe. Front Genet 2023; 14:1103331. [PMID: 36873952 PMCID: PMC9978111 DOI: 10.3389/fgene.2023.1103331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Accepted: 01/27/2023] [Indexed: 02/18/2023] Open
Abstract
Dothistroma needle blight (DNB) is an important disease of Pinus species that can be caused by one of two distinct but closely related pathogens; Dothistroma septosporum and Dothistroma pini. Dothistroma septosporum has a wide geographic distribution and is relatively well-known. In contrast, D. pini is known only from the United States and Europe, and there is a distinct lack of knowledge regarding its population structure and genetic diversity. The recent development of 16 microsatellite markers for D. pini provided an opportunity to investigate the diversity, structure, and mode of reproduction for populations collected over a period of 12 years, on eight different hosts in Europe. In total, 345 isolates from Belgium, the Czech Republic, France, Hungary, Romania, Western Russia, Serbia, Slovakia, Slovenia, Spain, Switzerland, and Ukraine were screened using microsatellite and species-specific mating type markers. A total of 109 unique multilocus haplotypes were identified and structure analyses suggested that the populations are influenced by location rather than host species. Populations from France and Spain displayed the highest levels of genetic diversity followed by the population in Ukraine. Both mating types were detected in most countries, with the exception of Hungary, Russia and Slovenia. Evidence for sexual recombination was supported only in the population from Spain. The observed population structure and several shared haplotypes between non-bordering countries provides good evidence that the movement of D. pini in Europe has been strongly influenced by human activity in Europe.
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Affiliation(s)
- Ariska van der Nest
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, South Africa
| | - Michael J Wingfield
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, South Africa
| | - Dušan Sadiković
- Slovenian Forestry Institute, Ljubljana, Slovenia.,Southern Swedish Forest Research Centre, Swedish University of Agricultural Science, Alnarp, Sweden
| | - Martin S Mullett
- Phytophthora Research Centre, Mendel University in Brno, Brno, Czechia
| | - Benoit Marçais
- Université de Lorraine, INRAE-Grand-Est, UMR1136 Interactions Arbres, Microorganismes, Nancy, France
| | - Valentin Queloz
- Swiss Federal Research Institute WSL, Birmensdorf, Switzerland
| | - Katarina Adamčíková
- Institute of Forest Ecology Slovak Academy of Sciences, Department of Plant Pathology and Mycology, Nitra, Slovakia
| | - Kateryna Davydenko
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Science, Uppsala, Sweden.,Ukrainian Forest Research Institute, Forestry and Forest Melioration, Kharkiv, Ukraine, Slovakia
| | - Irene Barnes
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, South Africa
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Waheed A, Haxim Y, Islam W, Kahar G, Liu X, Zhang D. Role of pathogen's effectors in understanding host-pathogen interaction. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2022; 1869:119347. [PMID: 36055522 DOI: 10.1016/j.bbamcr.2022.119347] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 08/16/2022] [Accepted: 08/23/2022] [Indexed: 06/15/2023]
Abstract
Pathogens can pose challenges to plant growth and development at various stages of their life cycle. Two interconnected defense strategies prevent the growth of pathogens in plants, i.e., molecular patterns triggered immunity (PTI) and pathogenic effector-triggered immunity (ETI) that often provides resistance when PTI no longer functions as a result of pathogenic effectors. Plants may trigger an ETI defense response by directly or indirectly detecting pathogen effectors via their resistance proteins. A typical resistance protein is a nucleotide-binding receptor with leucine-rich sequences (NLRs) that undergo structural changes as they recognize their effectors and form associations with other NLRs. As a result of dimerization or oligomerization, downstream components activate "helper" NLRs, resulting in a response to ETI. It was thought that ETI is highly dependent on PTI. However, recent studies have found that ETI and PTI have symbiotic crosstalk, and both work together to create a robust system of plant defense. In this article, we have summarized the recent advances in understanding the plant's early immune response, its components, and how they cooperate in innate defense mechanisms. Moreover, we have provided the current perspective on engineering strategies for crop protection based on up-to-date knowledge.
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Affiliation(s)
- Abdul Waheed
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; Xinjiang Key Laboratory of Conservation and Utilization of Plant Gene Resources, Xinjiang Institute of Ecology & Geography, Chinese Academy of Sciences, Urumqi 830011, China; Turpan Eremophytes Botanical Garden, Chinese Academy of Sciences, Turpan 838008, China
| | - Yakupjan Haxim
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; Xinjiang Key Laboratory of Conservation and Utilization of Plant Gene Resources, Xinjiang Institute of Ecology & Geography, Chinese Academy of Sciences, Urumqi 830011, China; Turpan Eremophytes Botanical Garden, Chinese Academy of Sciences, Turpan 838008, China
| | - Waqar Islam
- Xinjiang Key Laboratory of Conservation and Utilization of Plant Gene Resources, Xinjiang Institute of Ecology & Geography, Chinese Academy of Sciences, Urumqi 830011, China; Xinjiang Key Laboratory of Desert Plant Roots Ecology and Vegetation Restoration, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
| | - Gulnaz Kahar
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; Xinjiang Key Laboratory of Conservation and Utilization of Plant Gene Resources, Xinjiang Institute of Ecology & Geography, Chinese Academy of Sciences, Urumqi 830011, China; Turpan Eremophytes Botanical Garden, Chinese Academy of Sciences, Turpan 838008, China
| | - Xiaojie Liu
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; Xinjiang Key Laboratory of Conservation and Utilization of Plant Gene Resources, Xinjiang Institute of Ecology & Geography, Chinese Academy of Sciences, Urumqi 830011, China; Turpan Eremophytes Botanical Garden, Chinese Academy of Sciences, Turpan 838008, China
| | - Daoyuan Zhang
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; Xinjiang Key Laboratory of Conservation and Utilization of Plant Gene Resources, Xinjiang Institute of Ecology & Geography, Chinese Academy of Sciences, Urumqi 830011, China; Turpan Eremophytes Botanical Garden, Chinese Academy of Sciences, Turpan 838008, China.
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Cox MP, Guo Y, Winter DJ, Sen D, Cauldron NC, Shiller J, Bradley EL, Ganley AR, Gerth ML, Lacey RF, McDougal RL, Panda P, Williams NM, Grunwald NJ, Mesarich CH, Bradshaw RE. Chromosome-level assembly of the Phytophthora agathidicida genome reveals adaptation in effector gene families. Front Microbiol 2022; 13:1038444. [PMID: 36406440 PMCID: PMC9667082 DOI: 10.3389/fmicb.2022.1038444] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 10/11/2022] [Indexed: 01/25/2023] Open
Abstract
Phytophthora species are notorious plant pathogens, with some causing devastating tree diseases that threaten the survival of their host species. One such example is Phytophthora agathidicida, the causal agent of kauri dieback - a root and trunk rot disease that kills the ancient, iconic and culturally significant tree species, Agathis australis (New Zealand kauri). A deeper understanding of how Phytophthora pathogens infect their hosts and cause disease is critical for the development of effective treatments. Such an understanding can be gained by interrogating pathogen genomes for effector genes, which are involved in virulence or pathogenicity. Although genome sequencing has become more affordable, the complete assembly of Phytophthora genomes has been problematic, particularly for those with a high abundance of repetitive sequences. Therefore, effector genes located in repetitive regions could be truncated or missed in a fragmented genome assembly. Using a combination of long-read PacBio sequences, chromatin conformation capture (Hi-C) and Illumina short reads, we assembled the P. agathidicida genome into ten complete chromosomes, with a genome size of 57 Mb including 34% repeats. This is the first Phytophthora genome assembled to chromosome level and it reveals a high level of syntenic conservation with the complete genome of Peronospora effusa, the only other completely assembled genome sequence of an oomycete. All P. agathidicida chromosomes have clearly defined centromeres and contain candidate effector genes such as RXLRs and CRNs, but in different proportions, reflecting the presence of gene family clusters. Candidate effector genes are predominantly found in gene-poor, repeat-rich regions of the genome, and in some cases showed a high degree of duplication. Analysis of candidate RXLR effector genes that occur in multicopy gene families indicated half of them were not expressed in planta. Candidate CRN effector gene families showed evidence of transposon-mediated recombination leading to new combinations of protein domains, both within and between chromosomes. Further analysis of this complete genome assembly will help inform new methods of disease control against P. agathidicida and other Phytophthora species, ultimately helping decipher how Phytophthora pathogens have evolved to shape their effector repertoires and how they might adapt in the future.
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Affiliation(s)
- Murray P. Cox
- Laboratory of Molecular Plant Pathology/Bioprotection Aotearoa, School of Natural Sciences, Massey University, Palmerston North, New Zealand
| | - Yanan Guo
- Laboratory of Molecular Plant Pathology/Bioprotection Aotearoa, School of Natural Sciences, Massey University, Palmerston North, New Zealand
| | - David J. Winter
- Institute of Environmental Science and Research (ESR), Porirua, New Zealand
| | | | - Nicholas C. Cauldron
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, United States
| | | | - Ellie L. Bradley
- Laboratory of Molecular Plant Pathology/Bioprotection Aotearoa, School of Agriculture and Environment, Massey University, Palmerston North, New Zealand
| | - Austen R. Ganley
- School of Biological Sciences and Digital Life Institute, University of Auckland, Auckland, New Zealand
| | - Monica L. Gerth
- Bioprotection Aotearoa, School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Randy F. Lacey
- Bioprotection Aotearoa, School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | | | | | | | - Niklaus J. Grunwald
- Horticultural Crops Disease and Pest Management Research Unit, USDA Agricultural Research Service, Corvallis, OR, United States
| | - Carl H. Mesarich
- Laboratory of Molecular Plant Pathology/Bioprotection Aotearoa, School of Agriculture and Environment, Massey University, Palmerston North, New Zealand
| | - Rosie E. Bradshaw
- Laboratory of Molecular Plant Pathology/Bioprotection Aotearoa, School of Natural Sciences, Massey University, Palmerston North, New Zealand,*Correspondence: Rosie E. Bradshaw,
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Tarallo M, McDougal RL, Chen Z, Wang Y, Bradshaw RE, Mesarich CH. Characterization of two conserved cell death elicitor families from the Dothideomycete fungal pathogens Dothistroma septosporum and Fulvia fulva (syn. Cladosporium fulvum). Front Microbiol 2022; 13:964851. [PMID: 36160260 PMCID: PMC9493481 DOI: 10.3389/fmicb.2022.964851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 08/15/2022] [Indexed: 11/25/2022] Open
Abstract
Dothistroma septosporum (Ds) and Fulvia fulva (Ff; previously called Cladosporium fulvum) are two closely related Dothideomycete fungal species that cause Dothistroma needle blight in pine and leaf mold in tomato, respectively. During host colonization, these pathogens secrete virulence factors termed effectors to promote infection. In the presence of corresponding host immune receptors, however, these effectors activate plant defenses, including a localized cell death response that halts pathogen growth. We identified two apoplastic effector protein families, Ecp20 and Ecp32, which are conserved between the two pathogens. The Ecp20 family has four paralogues in both species, while the Ecp32 family has four paralogues in D. septosporum and five in F. fulva. Both families have members that are highly expressed during host infection. Members of the Ecp20 family have predicted structural similarity to proteins with a β-barrel fold, including the Alt a 1 allergen from Alternaria alternata, while members of the Ecp32 family have predicted structural similarity to proteins with a β-trefoil fold, such as trypsin inhibitors and lectins. Using Agrobacterium tumefaciens-mediated transient transformation assays, each family member was assessed for its ability to trigger cell death in leaves of the non-host species Nicotiana benthamiana and N. tabacum. Using this approach, FfEcp20-2, DsEcp20-3, and FfEcp20-3 from the Ecp20 family, and all members from the Ecp32 family, except for the Ds/FfEcp32-4 pair, triggered cell death in both species. This cell death was dependent on secretion of the effectors to the apoplast. In line with recognition by an extracellular immune receptor, cell death triggered by Ds/FfEcp20-3 and FfEcp32-3 was compromised in N. benthamiana silenced for BAK1 or SOBIR1, which encode extracellular co-receptors involved in transducing defense response signals following apoplastic effector recognition. We then investigated whether DsEcp20-3 and DsEcp20-4 triggered cell death in the host species Pinus radiata by directly infiltrating purified protein into pine needles. Strikingly, as in the non-host species, DsEcp20-3 triggered cell death, while DsEcp20-4 did not. Collectively, our study describes two new candidate effector families with cell death-eliciting activity from D. septosporum and F. fulva and provides evidence that members of these families are recognized by plant immune receptors.
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Affiliation(s)
- Mariana Tarallo
- Laboratory of Molecular Plant Pathology/Bioprotection Aotearoa, School of Natural Sciences, Massey University, Palmerston North, New Zealand
- *Correspondence: Mariana Tarallo,
| | | | - Zhiyuan Chen
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing, China
| | - Yan Wang
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing, China
| | - Rosie E. Bradshaw
- Laboratory of Molecular Plant Pathology/Bioprotection Aotearoa, School of Natural Sciences, Massey University, Palmerston North, New Zealand
- Rosie E. Bradshaw,
| | - Carl H. Mesarich
- Laboratory of Molecular Plant Pathology/Bioprotection Aotearoa, School of Agriculture and Environment, Massey University, Palmerston North, New Zealand
- Carl H. Mesarich,
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McCarthy HM, Tarallo M, Mesarich CH, McDougal RL, Bradshaw RE. Targeted Gene Mutations in the Forest Pathogen Dothistroma septosporum Using CRISPR/Cas9. PLANTS (BASEL, SWITZERLAND) 2022; 11:plants11081016. [PMID: 35448744 PMCID: PMC9025729 DOI: 10.3390/plants11081016] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 04/04/2022] [Accepted: 04/04/2022] [Indexed: 05/19/2023]
Abstract
Dothistroma needle blight, caused by Dothistroma septosporum, has increased in incidence and severity over the last few decades and is now one of the most important global diseases of pines. Disease resistance breeding could be accelerated by knowledge of pathogen virulence factors and their host targets. However, this is hindered due to inefficient targeted gene disruption in D. septosporum, which is required for virulence gene characterisation. Here we report the first successful application of CRISPR/Cas9 gene editing to a Dothideomycete forest pathogen, D. septosporum. Disruption of the dothistromin pathway regulator gene AflR, with a known phenotype, was performed using nonhomologous end-joining repair with an efficiency of > 90%. Transformants with a range of disruption mutations in AflR were produced. Disruption of Ds74283, a D. septosporum gene encoding a secreted cell death elicitor, was also achieved using CRISPR/Cas9, by using a specific donor DNA repair template to aid selection where the phenotype was unknown. In this case, 100% of screened transformants were identified as disruptants. In establishing CRISPR/Cas9 as a tool for gene editing in D. septosporum, our research could fast track the functional characterisation of candidate virulence factors in D. septosporum and helps set the foundation for development of this technology in other forest pathogens.
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Affiliation(s)
- Hannah M. McCarthy
- BioProtection Aotearoa, School of Natural Sciences, Massey University, Palmerston North 4472, New Zealand; (M.T.); (R.E.B.)
- Correspondence:
| | - Mariana Tarallo
- BioProtection Aotearoa, School of Natural Sciences, Massey University, Palmerston North 4472, New Zealand; (M.T.); (R.E.B.)
| | - Carl H. Mesarich
- BioProtection Aotearoa, School of Agriculture and Environment, Massey University, Palmerston North 4472, New Zealand;
| | - Rebecca L. McDougal
- Scion, New Zealand Forest Research Institute Ltd., Rotorua 3010, New Zealand;
| | - Rosie E. Bradshaw
- BioProtection Aotearoa, School of Natural Sciences, Massey University, Palmerston North 4472, New Zealand; (M.T.); (R.E.B.)
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Hunziker L, Tarallo M, Gough K, Guo M, Hargreaves C, Loo TS, McDougal RL, Mesarich CH, Bradshaw RE. Apoplastic effector candidates of a foliar forest pathogen trigger cell death in host and non-host plants. Sci Rep 2021; 11:19958. [PMID: 34620932 PMCID: PMC8497623 DOI: 10.1038/s41598-021-99415-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 09/22/2021] [Indexed: 11/23/2022] Open
Abstract
Forests are under threat from pests, pathogens, and changing climate. A major forest pathogen worldwide is the hemibiotroph Dothistroma septosporum, which causes dothistroma needle blight (DNB) of pines. While D. septosporum uses effector proteins to facilitate host infection, it is currently unclear whether any of these effectors are recognised by immune receptors to activate the host immune system. Such information is needed to identify and select disease resistance against D. septosporum in pines. We predicted and investigated apoplastic D. septosporum candidate effectors (DsCEs) using bioinformatics and plant-based experiments. We discovered DsCEs that trigger cell death in the angiosperm Nicotiana spp., indicative of a hypersensitive defence response and suggesting their recognition by immune receptors in non-host plants. In a first for foliar forest pathogens, we developed a novel protein infiltration method to show that tissue-cultured pine shoots can respond with a cell death response to a DsCE, as well as to a reference cell death-inducing protein. The conservation of responses across plant taxa suggests that knowledge of pathogen-angiosperm interactions may also be relevant to pathogen-gymnosperm interactions. These results contribute to our understanding of forest pathogens and may ultimately provide clues to disease immunity in both commercial and natural forests.
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Affiliation(s)
- Lukas Hunziker
- Centre for Crop and Disease Management, Curtin University, Bentley, Perth, 6102, Australia
| | - Mariana Tarallo
- Bio-Protection Research Centre, School of Fundamental Sciences, Massey University, Palmerston North, 4474, New Zealand
| | - Keiko Gough
- Scion, New Zealand Forest Research Institute Ltd, Rotorua, 3010, New Zealand
| | - Melissa Guo
- Bio-Protection Research Centre, School of Fundamental Sciences, Massey University, Palmerston North, 4474, New Zealand
| | - Cathy Hargreaves
- Scion, New Zealand Forest Research Institute Ltd, Rotorua, 3010, New Zealand
| | - Trevor S Loo
- Bio-Protection Research Centre, School of Fundamental Sciences, Massey University, Palmerston North, 4474, New Zealand
| | - Rebecca L McDougal
- Scion, New Zealand Forest Research Institute Ltd, Rotorua, 3010, New Zealand
| | - Carl H Mesarich
- Bio-Protection Research Centre, School of Agriculture and Environment, Massey University, Palmerston North, 4474, New Zealand
| | - Rosie E Bradshaw
- Bio-Protection Research Centre, School of Fundamental Sciences, Massey University, Palmerston North, 4474, New Zealand.
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Lu M, Feau N, Vidakovic DO, Ukrainetz N, Wong B, Aitken SN, Hamelin RC, Yeaman S. Comparative Gene Expression Analysis Reveals Mechanism of Pinus contorta Response to the Fungal Pathogen Dothistroma septosporum. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2021; 34:397-409. [PMID: 33258711 DOI: 10.1094/mpmi-10-20-0282-r] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Many conifers have distributions that span wide ranges in both biotic and abiotic conditions, but the basis of response to biotic stress has received much less attention than response to abiotic stress. In this study, we investigated the gene expression response of lodgepole pine (Pinus contorta) to attack by the fungal pathogen Dothistroma septosporum, which causes Dothistroma needle blight, a disease that has caused severe climate-related outbreaks in northwestern British Columbia. We inoculated tolerant and susceptible pines with two D. septosporum isolates and analyzed the differentially expressed genes (DEGs), differential exon usage, and coexpressed gene modules using RNA-sequencing data. We found a rapid and strong transcriptomic response in tolerant lodgepole pine samples inoculated with one D. septosporum isolate, and a late and weak response in susceptible samples inoculated with another isolate. We mapped 43 of the DEG- or gene module-identified genes to the reference plant-pathogen interaction pathway deposited in the Kyoto Encyclopedia of Genes and Genomes database. These genes are present in PAMP-triggered and effector-triggered immunity pathways. Genes comprising pathways and gene modules had signatures of strong selective constraint, while the highly expressed genes in tolerant samples appear to have been favored by selection to counterattack the pathogen. We identified candidate resistance genes that may respond to D. septosporum effectors. Taken together, our results show that gene expression response to D. septosporum infection in lodgepole pine varies both among tree genotypes and pathogen strains and involves both known candidate genes and a number of genes with previously unknown functions.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
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Affiliation(s)
- Mengmeng Lu
- Department of Biological Sciences, University of Calgary, 507 Campus Drive NW, Calgary, Canada
| | - Nicolas Feau
- Department of Forest and Conservation Sciences, University of British Columbia, 3041-2424 Main Mall, Vancouver, Canada
| | - Dragana Obreht Vidakovic
- Department of Forest and Conservation Sciences, University of British Columbia, 3041-2424 Main Mall, Vancouver, Canada
| | - Nicholas Ukrainetz
- Forest Improvement and Research Management Branch, Ministry of Forests, Lands and Natural Resource Operations & Rural Development, 18793-32nd Ave., Surrey, Canada
| | - Barbara Wong
- Institut de Biologie Intégrative et des Systèmes, Université Laval, Pavillon Charles-Eugène-Marchand 1030, avenue de la Médecine, Québec, Canada
| | - Sally N Aitken
- Department of Forest and Conservation Sciences, University of British Columbia, 3041-2424 Main Mall, Vancouver, Canada
| | - Richard C Hamelin
- Department of Forest and Conservation Sciences, University of British Columbia, 3041-2424 Main Mall, Vancouver, Canada
- Institut de Biologie Intégrative et des Systèmes, Université Laval, Pavillon Charles-Eugène-Marchand 1030, avenue de la Médecine, Québec, Canada
| | - Sam Yeaman
- Department of Biological Sciences, University of Calgary, 507 Campus Drive NW, Calgary, Canada
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