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Coomber A, Saville A, Ristaino JB. Evolution of Phytophthora infestans on its potato host since the Irish potato famine. Nat Commun 2024; 15:6488. [PMID: 39103347 DOI: 10.1038/s41467-024-50749-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 07/18/2024] [Indexed: 08/07/2024] Open
Abstract
Phytophthora infestans is a major oomycete plant pathogen, responsible for potato late blight, which led to the Irish Potato Famine from 1845-1852. Since then, potatoes resistant to this disease have been bred and deployed worldwide. Their resistance (R) genes recognize pathogen effectors responsible for virulence and then induce a plant response stopping disease progression. However, most deployed R genes are quickly overcome by the pathogen. We use targeted sequencing of effector and R genes on herbarium specimens to examine the joint evolution in both P. infestans and potato from 1845-1954. Currently relevant effectors are historically present in P. infestans, but with alternative alleles compared to modern reference genomes. The historic FAM-1 lineage has the virulent Avr1 allele and the ability to break the R1 resistance gene before breeders deployed it in potato. The FAM-1 lineage is diploid, but later, triploid US-1 lineages appear. We show that pathogen virulence genes and host resistance genes have undergone significant changes since the Famine, from both natural and artificial selection.
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Affiliation(s)
- Allison Coomber
- Department of Entomology and Plant Pathology, NC State University, Raleigh, NC, USA
- Functional Genomics Program, NC State University, Raleigh, NC, USA
| | - Amanda Saville
- Department of Entomology and Plant Pathology, NC State University, Raleigh, NC, USA
| | - Jean Beagle Ristaino
- Department of Entomology and Plant Pathology, NC State University, Raleigh, NC, USA.
- Emerging Plant Disease and Global Food Security Cluster, NC State University, Raleigh, NC, USA.
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2
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Paluchowska P, Śliwka J, Yin Z. Late blight resistance genes in potato breeding. PLANTA 2022; 255:127. [PMID: 35576021 PMCID: PMC9110483 DOI: 10.1007/s00425-022-03910-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 05/01/2022] [Indexed: 06/15/2023]
Abstract
Using late blight resistance genes targeting conservative effectors of Phytophthora infestans and the constructing gene pyramids may lead to durable, broad-spectrum resistance, which could be accelerated through genetic engineering. Potato (Solanum tuberosum L.) is one of the most important food crops worldwide. In 2020, potato production was estimated to be more than 359 million tons according to the Food and Agriculture Organization (FAO). Potato is affected by many pathogens, among which Phytophthora infestans, causing late blight, is of the most economic importance. Crop protection against late blight requires intensive use of fungicides, which has an impact on the environment and humans. Therefore, new potato cultivars have been bred using resistance genes against P. infestans (Rpi genes) that originate from wild relatives of potato. Such programmes were initiated 100 years ago, but the process is complex and long. The development of genetic engineering techniques has enabled the direct transfer of resistance genes from potato wild species to cultivars and easier pyramiding of multiple Rpi genes, which potentially increases the durability and spectrum of potato resistance to rapidly evolving P. infestans strains. In this review, we summarize the current knowledge concerning Rpi genes. We also discuss the use of Rpi genes in breeding as well as their detection in existing potato cultivars. Last, we review new sources of Rpi genes and new methods used to identify them and discuss interactions between P. infestans and host.
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Affiliation(s)
- Paulina Paluchowska
- Plant Breeding and Acclimatization Institute-National Research Institute, Platanowa 19, 05-831, Młochów, Poland.
| | - Jadwiga Śliwka
- Plant Breeding and Acclimatization Institute-National Research Institute, Platanowa 19, 05-831, Młochów, Poland
| | - Zhimin Yin
- Plant Breeding and Acclimatization Institute-National Research Institute, Platanowa 19, 05-831, Młochów, Poland
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3
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El-Ganainy SM, Iqbal Z, Awad HM, Sattar MN, Tohamy AM, Abbas AO, Squires J, Cooke DEL. Genotypic and Phenotypic Structure of the Population of Phytophthora infestans in Egypt Revealed the Presence of European Genotypes. J Fungi (Basel) 2022; 8:jof8050468. [PMID: 35628724 PMCID: PMC9147654 DOI: 10.3390/jof8050468] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Revised: 04/27/2022] [Accepted: 04/28/2022] [Indexed: 12/10/2022] Open
Abstract
Late blight disease of potato and tomato, caused by Phytophthora infestans, results in serious losses to Egyptian and global potato and tomato production. To understand the structure and dynamics of the Egyptian population of P. infestans, 205 isolates were collected from potato and tomato plants during three growing seasons in 2010–2012. The characterization was achieved by mating-type assay, metalaxyl sensitivity assay, and virulence pattern. Additionally, genotyping of 85 Egyptian isolates and 15 reference UK isolates was performed using 12 highly informative microsatellite (SSR) markers David E. L. Cooke and five effector (RxLR) genes. Mating-type testing showed that 58% (118 of 205) of the isolates belonged to mating type A1, 35% (71 isolates) to mating type A2, and the rest 8% (16 isolates) were self-fertile. The phenotype of metalaxyl response was represented as 45% resistant, 43% sensitive, and 12% as intermediate. Structure analysis grouped the 85 identified genotypes into two main clonal lineages. The first clonal lineage comprised 21 isolates belonging to A2 mating type and 8 self-fertile isolates. This clonal lineage was identified as Blue_13 or EU_13_A2. The second main clonal lineage comprised 55 isolates and was identified as EU_23_A1. A single isolate with a novel SSR genotype that formed a distinct genetic grouping was also identified. The effector sequencing showed good correspondence with the virulence data and highlighted differences in the presence and absence of loci as well as nucleotide polymorphism that affect gene function. This study indicated a changing population of P. infestans in Egypt and discusses the findings in the context of late blight management.
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Affiliation(s)
- Sherif Mohamed El-Ganainy
- Department of Arid Land Agriculture, College of Agriculture and Food Sciences, King Faisal University, P.O. Box 420, Al-Ahsa 31982, Saudi Arabia
- Vegetable Diseases Research Department, Plant Pathology Research Institute, ARC, Giza 12619, Egypt;
- Correspondence: (S.M.E.-G.); (D.E.L.C.)
| | - Zafar Iqbal
- Central Laboratories, King Faisal University, P.O. Box 420, Al-Ahsa 31982, Saudi Arabia; (Z.I.); (M.N.S.)
| | - Hossam Mohamed Awad
- Agriculture Botany Department, Menofia University, Shibin El-Kom 32415, Egypt;
| | - Muhammad Naeem Sattar
- Central Laboratories, King Faisal University, P.O. Box 420, Al-Ahsa 31982, Saudi Arabia; (Z.I.); (M.N.S.)
| | - Abdel Mohsen Tohamy
- Vegetable Diseases Research Department, Plant Pathology Research Institute, ARC, Giza 12619, Egypt;
| | - Ahmed O. Abbas
- Department of Animal and Fish Production, College of Agricultural and Food Sciences, King Faisal University, P.O. Box 420, Al-Ahsa 31982, Saudi Arabia;
| | | | - David E. L. Cooke
- The James Hutton Institute, Dundee DD2 5DA, UK;
- Correspondence: (S.M.E.-G.); (D.E.L.C.)
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Sun K, Schipper D, Jacobsen E, Visser RGF, Govers F, Bouwmeester K, Bai Y. Silencing susceptibility genes in potato hinders primary infection of Phytophthora infestans at different stages. HORTICULTURE RESEARCH 2022; 9:uhab058. [PMID: 35043191 PMCID: PMC8968627 DOI: 10.1093/hr/uhab058] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Accepted: 11/12/2021] [Indexed: 06/01/2023]
Abstract
Most potato cultivars are susceptible to late blight disease caused by the oomycete pathogen Phytophthora infestans. A new source of resistance to prevent or diminish pathogen infection is found in the genetic loss of host susceptibility. Previously, we showed that RNAi-mediated silencing of the potato susceptibility (S) genes StDND1, StDMR1 and StDMR6 leads to increased late blight resistance. The mechanisms underlying this S-gene mediated resistance have thus far not been identified. In this study, we examined the infection process of P. infestans on StDND1-, StDMR1- and StDMR6-silenced potato lines. Microscopic analysis showed that penetration of P. infestans spores was hampered on StDND1-silenced plants. On StDMR1- and StDMR6-silenced plants, P. infestans infection was arrested at a primary infection stage by enhanced cell death responses. Histochemical staining revealed that StDMR1- and StDMR6-silenced plants display elevated ROS levels in cells at the infection sites. Resistance in StDND1-silenced plants, however, seems not to rely on a cell death response as ROS accumulation was found to be absent at most inoculated sites. Quantitative analysis of marker gene expression suggests that the increased resistance observed in StDND1- and StDMR6-silenced plants relies on an early onset of SA- and ET-mediated signalling pathways. Resistance mediated by silencing StDMR1 was found to be correlated with the early induction of SA-mediated signalling. These data provide evidence that different defense mechanisms are involved in late blight resistance mediated by functional impairment of different potato S-genes.
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Affiliation(s)
- Kaile Sun
- College of Horticulture, Henan Agricultural University, Nongye Road 63, 450002 Zhengzhou, Henan, China
- Plant Breeding, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Danny Schipper
- Plant Breeding, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Evert Jacobsen
- Plant Breeding, 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
| | - Francine Govers
- Laboratory of Phytopathology, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands
| | - Klaas Bouwmeester
- Laboratory of Phytopathology, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands
- Biosystematics Group, 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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Ivanov AA, Ukladov EO, Golubeva TS. Phytophthora infestans: An Overview of Methods and Attempts to Combat Late Blight. J Fungi (Basel) 2021; 7:1071. [PMID: 34947053 PMCID: PMC8707485 DOI: 10.3390/jof7121071] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Revised: 12/10/2021] [Accepted: 12/11/2021] [Indexed: 12/20/2022] Open
Abstract
Phytophthora infestans (Mont.) de Bary is one of the main pathogens in the agricultural sector. The most affected are the Solanaceae species, with the potato (Solanum tuberosum) and the tomato (Solanum lycopersicum) being of great agricultural importance. Ornamental Solanaceae can also host the pests Petunia spp., Calibrachoa spp., as well as the wild species Solanum dulcamara, Solanum sarrachoides, etc. Annual crop losses caused by this pathogen are highly significant. Although the interaction between P. infestans and the potato has been investigated for a long time, further studies are still needed. This review summarises the basic approaches in the fight against the late blight over the past 20 years and includes four sections devoted to methods of control: (1) fungicides; (2) R-gene-based resistance of potato species; (3) RNA interference approaches; (4) other approaches to control P. infestans. Based on the latest advances, we have provided a description of the significant advantages and disadvantages of each approach.
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Affiliation(s)
- Artemii A. Ivanov
- Institute of Cytology and Genetics SB RAS, 630090 Novosibirsk, Russia;
- Faculty of Natural Sciences, Novosibirsk State University, 630090 Novosibirsk, Russia;
| | - Egor O. Ukladov
- Faculty of Natural Sciences, Novosibirsk State University, 630090 Novosibirsk, Russia;
| | - Tatiana S. Golubeva
- Institute of Cytology and Genetics SB RAS, 630090 Novosibirsk, Russia;
- Faculty of Natural Sciences, Novosibirsk State University, 630090 Novosibirsk, Russia;
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Duggan C, Moratto E, Savage Z, Hamilton E, Adachi H, Wu CH, Leary AY, Tumtas Y, Rothery SM, Maqbool A, Nohut S, Martin TR, Kamoun S, Bozkurt TO. Dynamic localization of a helper NLR at the plant-pathogen interface underpins pathogen recognition. Proc Natl Acad Sci U S A 2021; 118:e2104997118. [PMID: 34417294 PMCID: PMC8403872 DOI: 10.1073/pnas.2104997118] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Plants employ sensor-helper pairs of NLR immune receptors to recognize pathogen effectors and activate immune responses. Yet, the subcellular localization of NLRs pre- and postactivation during pathogen infection remains poorly understood. Here, we show that NRC4, from the "NRC" solanaceous helper NLR family, undergoes dynamic changes in subcellular localization by shuttling to and from the plant-pathogen haustorium interface established during infection by the Irish potato famine pathogen Phytophthora infestans. Specifically, prior to activation, NRC4 accumulates at the extrahaustorial membrane (EHM), presumably to mediate response to perihaustorial effectors that are recognized by NRC4-dependent sensor NLRs. However, not all NLRs accumulate at the EHM, as the closely related helper NRC2 and the distantly related ZAR1 did not accumulate at the EHM. NRC4 required an intact N-terminal coiled-coil domain to accumulate at the EHM, whereas the functionally conserved MADA motif implicated in cell death activation and membrane insertion was dispensable for this process. Strikingly, a constitutively autoactive NRC4 mutant did not accumulate at the EHM and showed punctate distribution that mainly associated with the plasma membrane, suggesting that postactivation, NRC4 may undergo a conformation switch to form clusters that do not preferentially associate with the EHM. When NRC4 is activated by a sensor NLR during infection, however, NRC4 forms puncta mainly at the EHM and, to a lesser extent, at the plasma membrane. We conclude that following activation at the EHM, NRC4 may spread to other cellular membranes from its primary site of activation to trigger immune responses.
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Affiliation(s)
- Cian Duggan
- Department of Life Sciences, Imperial College, SW7 2AZ London, United Kingdom
| | - Eleonora Moratto
- Department of Life Sciences, Imperial College, SW7 2AZ London, United Kingdom
| | - Zachary Savage
- Department of Life Sciences, Imperial College, SW7 2AZ London, United Kingdom
| | - Eranthika Hamilton
- Department of Life Sciences, Imperial College, SW7 2AZ London, United Kingdom
| | - Hiroaki Adachi
- The Sainsbury Laboratory, University of East Anglia, NR4 7UH Norwich, United Kingdom
- Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma 630-0192, Japan
| | - Chih-Hang Wu
- The Sainsbury Laboratory, University of East Anglia, NR4 7UH Norwich, United Kingdom
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Alexandre Y Leary
- Department of Life Sciences, Imperial College, SW7 2AZ London, United Kingdom
| | - Yasin Tumtas
- Department of Life Sciences, Imperial College, SW7 2AZ London, United Kingdom
| | - Stephen M Rothery
- Department of Life Sciences, Imperial College, SW7 2AZ London, United Kingdom
| | - Abbas Maqbool
- The Sainsbury Laboratory, University of East Anglia, NR4 7UH Norwich, United Kingdom
| | - Seda Nohut
- Department of Life Sciences, Imperial College, SW7 2AZ London, United Kingdom
| | - Toby Ross Martin
- Department of Life Sciences, Imperial College, SW7 2AZ London, United Kingdom
| | - Sophien Kamoun
- The Sainsbury Laboratory, University of East Anglia, NR4 7UH Norwich, United Kingdom
| | - Tolga Osman Bozkurt
- Department of Life Sciences, Imperial College, SW7 2AZ London, United Kingdom;
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Overdijk EJR, Putker V, Smits J, Tang H, Bouwmeester K, Govers F, Ketelaar T. Phytophthora infestans RXLR effector AVR1 disturbs the growth of Physcomitrium patens without affecting Sec5 localization. PLoS One 2021; 16:e0249637. [PMID: 33831039 PMCID: PMC8031463 DOI: 10.1371/journal.pone.0249637] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 03/22/2021] [Indexed: 11/19/2022] Open
Abstract
Plant pathogens often exploit a whole range of effectors to facilitate infection. The RXLR effector AVR1 produced by the oomycete plant pathogen Phytophthora infestans suppresses host defense by targeting Sec5. Sec5 is a subunit of the exocyst, a protein complex that is important for mediating polarized exocytosis during plant development and defense against pathogens. The mechanism by which AVR1 manipulates Sec5 functioning is unknown. In this study, we analyzed the effect of AVR1 on Sec5 localization and functioning in the moss Physcomitrium patens. P. patens has four Sec5 homologs. Two (PpSec5b and PpSec5d) were found to interact with AVR1 in yeast-two-hybrid assays while none of the four showed a positive interaction with AVR1ΔT, a truncated version of AVR1. In P. patens lines carrying β-estradiol inducible AVR1 or AVR1ΔT transgenes, expression of AVR1 or AVR1ΔT caused defects in the development of caulonemal protonema cells and abnormal morphology of chloronema cells. Similar phenotypes were observed in Sec5- or Sec6-silenced P. patens lines, suggesting that both AVR1 and AVR1ΔT affect exocyst functioning in P. patens. With respect to Sec5 localization we found no differences between β-estradiol-treated and untreated transgenic AVR1 lines. Sec5 localizes at the plasma membrane in growing caulonema cells, also during pathogen attack, and its subcellular localization is the same, with or without AVR1 in the vicinity.
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Affiliation(s)
- Elysa J. R. Overdijk
- Laboratory of Cell Biology, Wageningen University & Research, Wageningen, The Netherlands
- Laboratory of Phytopathology, Wageningen University & Research, Wageningen, The Netherlands
| | - Vera Putker
- Laboratory of Cell Biology, Wageningen University & Research, Wageningen, The Netherlands
| | - Joep Smits
- Laboratory of Cell Biology, Wageningen University & Research, Wageningen, The Netherlands
| | - Han Tang
- Laboratory of Cell Biology, Wageningen University & Research, Wageningen, The Netherlands
| | - Klaas Bouwmeester
- Laboratory of Phytopathology, Wageningen University & Research, Wageningen, The Netherlands
- Biosystematics Group, Wageningen University & Research, Wageningen, The Netherlands
| | - Francine Govers
- Laboratory of Phytopathology, Wageningen University & Research, Wageningen, The Netherlands
- * E-mail:
| | - Tijs Ketelaar
- Laboratory of Cell Biology, Wageningen University & Research, Wageningen, The Netherlands
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8
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Morales JG, Gaviria AE, Gilchrist E. Allelic Variation and Selection in Effector Genes of Phytophthora infestans (Mont.) de Bary. Pathogens 2020; 9:pathogens9070551. [PMID: 32659973 PMCID: PMC7400436 DOI: 10.3390/pathogens9070551] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Revised: 07/02/2020] [Accepted: 07/06/2020] [Indexed: 12/12/2022] Open
Abstract
Phytophthora infestans is a devastating plant pathogen in several crops such as potato (Solanum tuberosum), tomato (Solanum lycopersicum) and Andean fruits such as tree tomato (Solanum betaceum), lulo (Solanum quitoense), uchuva (Physalis peruviana) and wild species in the genus Solanum sp. Despite intense research performed around the world, P. infestans populations from Colombia, South America, are poorly understood. Of particular importance is knowledge about pathogen effector proteins, which are responsible for virulence. The present work was performed with the objective to analyze gene sequences coding for effector proteins of P. infestans from isolates collected from different hosts and geographical regions. Several genetic parameters, phylogenetic analyses and neutrality tests for non-synonymous and synonymous substitutions were calculated. Non-synonymous substitutions were identified for all genes that exhibited polymorphisms at the DNA level. Significant negative selection values were found for two genes (PITG_08994 and PITG_12737) suggesting active coevolution with the corresponding host resistance proteins. Implications for pathogen virulence mechanisms and disease management are discussed.
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Affiliation(s)
- Juan G. Morales
- Group and Laboratory of Fitotecnia Tropical, Departamento de Ciencias Agronómicas, Facultad de Ciencias Agrarias, Universidad Nacional de Colombia sede Medellín, Medellín, 050034 Antioquia, Colombia; (A.E.G.); (E.G.)
- Correspondence: ; Tel.: +0057-4-4309088
| | - Astrid E. Gaviria
- Group and Laboratory of Fitotecnia Tropical, Departamento de Ciencias Agronómicas, Facultad de Ciencias Agrarias, Universidad Nacional de Colombia sede Medellín, Medellín, 050034 Antioquia, Colombia; (A.E.G.); (E.G.)
| | - Elizabeth Gilchrist
- Group and Laboratory of Fitotecnia Tropical, Departamento de Ciencias Agronómicas, Facultad de Ciencias Agrarias, Universidad Nacional de Colombia sede Medellín, Medellín, 050034 Antioquia, Colombia; (A.E.G.); (E.G.)
- Universidad EAFIT, 050034 Medellín, Colombia
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Derbyshire MC. Bioinformatic Detection of Positive Selection Pressure in Plant Pathogens: The Neutral Theory of Molecular Sequence Evolution in Action. Front Microbiol 2020; 11:644. [PMID: 32328056 PMCID: PMC7160247 DOI: 10.3389/fmicb.2020.00644] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 03/20/2020] [Indexed: 11/13/2022] Open
Abstract
The genomes of plant pathogenic fungi and oomycetes are often exposed to strong positive selection pressure. During speciation, shifts in host range and preference can lead to major adaptive changes. Furthermore, evolution of total host resistance to most isolates can force rapid evolutionary changes in host-specific pathogens. Crop pathogens are subjected to particularly intense selective pressures from monocultures and fungicides. Detection of the footprints of positive selection in plant pathogen genomes is a worthwhile endeavor as it aids understanding of the fundamental biology of these important organisms. There are two main classes of test for detection of positively selected alleles. Tests based on the ratio of non-synonymous to synonymous substitutions per site detect the footprints of multiple fixation events between divergent lineages. Thus, they are well-suited to the study of ancient adaptation events spanning speciations. On the other hand, tests that scan genomes for local fluctuations in allelic diversity within populations are suitable for detection of recent positive selection in populations. In this review, I briefly describe some of the more widely used tests of positive selection and the theory underlying them. I then discuss various examples of their application to plant pathogen genomes, emphasizing the types of genes that are associated with signatures of positive selection. I conclude with a discussion of the practicality of such tests for identification of pathogen genes of interest and the important features of pathogen ecology that must be taken into account for accurate interpretation.
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Affiliation(s)
- Mark C. Derbyshire
- Centre for Crop and Disease Management, School of Molecular and Life Sciences, Curtin University, Perth, WA, Australia
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Naveed ZA, Wei X, Chen J, Mubeen H, Ali GS. The PTI to ETI Continuum in Phytophthora-Plant Interactions. FRONTIERS IN PLANT SCIENCE 2020; 11:593905. [PMID: 33391306 PMCID: PMC7773600 DOI: 10.3389/fpls.2020.593905] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 11/24/2020] [Indexed: 05/15/2023]
Abstract
Phytophthora species are notorious pathogens of several economically important crop plants. Several general elicitors, commonly referred to as Pathogen-Associated Molecular Patterns (PAMPs), from Phytophthora spp. have been identified that are recognized by the plant receptors to trigger induced defense responses in a process termed PAMP-triggered Immunity (PTI). Adapted Phytophthora pathogens have evolved multiple strategies to evade PTI. They can either modify or suppress their elicitors to avoid recognition by host and modulate host defense responses by deploying hundreds of effectors, which suppress host defense and physiological processes by modulating components involved in calcium and MAPK signaling, alternative splicing, RNA interference, vesicle trafficking, cell-to-cell trafficking, proteolysis and phytohormone signaling pathways. In incompatible interactions, resistant host plants perceive effector-induced modulations through resistance proteins and activate downstream components of defense responses in a quicker and more robust manner called effector-triggered-immunity (ETI). When pathogens overcome PTI-usually through effectors in the absence of R proteins-effectors-triggered susceptibility (ETS) ensues. Qualitatively, many of the downstream defense responses overlap between PTI and ETI. In general, these multiple phases of Phytophthora-plant interactions follow the PTI-ETS-ETI paradigm, initially proposed in the zigzag model of plant immunity. However, based on several examples, in Phytophthora-plant interactions, boundaries between these phases are not distinct but are rather blended pointing to a PTI-ETI continuum.
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Affiliation(s)
- Zunaira Afzal Naveed
- Department of Plant Pathology, Institute of Food and Agriculture Sciences, University of Florida, Gainesville, FL, United States
- Mid-Florida Research and Education Center, Institute of Food and Agriculture Sciences, University of Florida, Apopka, FL, United States
| | - Xiangying Wei
- Mid-Florida Research and Education Center, Institute of Food and Agriculture Sciences, University of Florida, Apopka, FL, United States
- Institute of Oceanography, Minjiang University, Fuzhou, China
- Xiangying Wei
| | - Jianjun Chen
- Mid-Florida Research and Education Center, Institute of Food and Agriculture Sciences, University of Florida, Apopka, FL, United States
| | - Hira Mubeen
- Departement of Biotechnology, University of Central Punjab, Lahore, Pakistan
| | - Gul Shad Ali
- Department of Plant Pathology, Institute of Food and Agriculture Sciences, University of Florida, Gainesville, FL, United States
- Mid-Florida Research and Education Center, Institute of Food and Agriculture Sciences, University of Florida, Apopka, FL, United States
- EukaryoTech LLC, Apopka, FL, United States
- *Correspondence: Gul Shad Ali
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11
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The Role of Peptide Signals Hidden in the Structure of Functional Proteins in Plant Immune Responses. Int J Mol Sci 2019; 20:ijms20184343. [PMID: 31491850 PMCID: PMC6770897 DOI: 10.3390/ijms20184343] [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: 08/05/2019] [Revised: 09/02/2019] [Accepted: 09/03/2019] [Indexed: 02/04/2023] Open
Abstract
Plants have evolved a sophisticated innate immune system to cope with a diverse range of phytopathogens and insect herbivores. Plasma-membrane-localized pattern recognition receptors (PRRs), such as receptor-like kinases (RLK), recognize special signals, pathogen- or damage-associated molecular patterns (PAMPs or DAMPs), and trigger immune responses. A growing body of evidence shows that many peptides hidden in both plant and pathogen functional protein sequences belong to the group of such immune signals. However, the origin, evolution, and release mechanisms of peptide sequences from functional and nonfunctional protein precursors, known as cryptic peptides, are largely unknown. Various special proteases, such as metacaspase or subtilisin-like proteases, are involved in the release of such peptides upon activation during defense responses. In this review, we discuss the roles of cryptic peptide sequences hidden in the structure of functional proteins in plant defense and plant-pathogen interactions.
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Liu L, Xu L, Jia Q, Pan R, Oelmüller R, Zhang W, Wu C. Arms race: diverse effector proteins with conserved motifs. PLANT SIGNALING & BEHAVIOR 2019; 14:1557008. [PMID: 30621489 PMCID: PMC6351098 DOI: 10.1080/15592324.2018.1557008] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Effector proteins play important roles in the infection by pathogenic oomycetes and fungi or the colonization by endophytic and mycorrhizal fungi. They are either translocated into the host plant cells via specific translocation mechanisms and function in the host's cytoplasm or nucleus, or they reside in the apoplast of the plant cells and act at the extracellular host-microbe interface. Many effector proteins possess conserved motifs (such as the RXLR, CRN, LysM, RGD, DELD, EAR, RYWT, Y/F/WXC or CFEM motifs) localized in their N- or C-terminal regions. Analysis of the functions of effector proteins, especially so-called "core effectors", is crucial for the understanding of pathogenicity/symbiosis mechanisms and plant defense strategies, and helps to develop breeding strategies for pathogen-resistant cultivars, and to increase crop yield and quality as well as abiotic stress resistance. This review summarizes current knowledge about these effector proteins with the conversed motifs and their involvement in pathogenic or mutualistic plant/fungal interactions.
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Affiliation(s)
- Liping Liu
- College of Horticulture & Gardening, Yangtze University, Jingzhou, China
| | - Le Xu
- Hubei Collaborative Innovation Center for Grain Industry/Research Center of Crop Stresses Resistance Technologies, Yangtze University, Jingzhou, China
| | - Qie Jia
- College of Horticulture & Gardening, Yangtze University, Jingzhou, China
| | - Rui Pan
- Hubei Collaborative Innovation Center for Grain Industry/Research Center of Crop Stresses Resistance Technologies, Yangtze University, Jingzhou, China
| | - Ralf Oelmüller
- Plant Physiology, Matthias-Schleiden-Institute for Genetics, Bioinformatics and Molecular Botany, Faculty of Biological Science, Friedrich-Schiller-University Jena, Jena, Germany
| | - Wenying Zhang
- Hubei Collaborative Innovation Center for Grain Industry/Research Center of Crop Stresses Resistance Technologies, Yangtze University, Jingzhou, China
- CONTACT Wenying Zhang Hubei Collaborative Innovation Center for Grain Industry/Research Center of Crop Stresses Resistance Technologies, Yangtze University, Jingzhou 434025, China; Chu Wu College of Horticulture & Gardening, Yangtze University, Jingzhou 434025, China
| | - Chu Wu
- College of Horticulture & Gardening, Yangtze University, Jingzhou, China
- Institute of Plant Ecology and Environmental Restoration, Yangtze University, Jingzhou, China
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