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Paineau M, Minio A, Mestre P, Fabre F, Mazet ID, Couture C, Legeai F, Dumartinet T, Cantu D, Delmotte F. Multiple deletions of candidate effector genes lead to the breakdown of partial grapevine resistance to downy mildew. THE NEW PHYTOLOGIST 2024; 243:1490-1505. [PMID: 39021210 DOI: 10.1111/nph.19861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 03/21/2024] [Indexed: 07/20/2024]
Abstract
Grapevine downy mildew, caused by the oomycete Plasmopara viticola (P. viticola, Berk. & M. A. Curtis; Berl. & De Toni), is a global threat to Eurasian wine grapes Vitis vinifera. Although resistant grapevine varieties are becoming more accessible, P. viticola populations are rapidly evolving to overcome these resistances. We aimed to uncover avirulence genes related to Rpv3.1-mediated grapevine resistance. We sequenced the genomes and characterized the development of 136 P. viticola strains on resistant and sensitive grapevine cultivars. A genome-wide association study was conducted to identify genomic variations associated with resistant-breaking phenotypes. We identified a genomic region associated with the breakdown of Rpv3.1 grapevine resistance (avrRpv3.1 locus). A diploid-aware reassembly of the P. viticola INRA-Pv221 genome revealed structural variations in this locus, including a 30 kbp deletion. Virulent P. viticola strains displayed multiple deletions on both haplotypes at the avrRpv3.1 locus. These deletions involve two paralog genes coding for proteins with 800-900 amino acids and signal peptides. These proteins exhibited a structure featuring LWY-fold structural modules, common among oomycete effectors. When transiently expressed, these proteins induced cell death in grapevines carrying Rpv3.1 resistance, confirming their avirulence nature. This discovery sheds light on the genetic mechanisms enabling P. viticola to adapt to grapevine resistance, laying a foundation for developing strategies to manage this destructive crop pathogen.
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Affiliation(s)
- Manon Paineau
- INRAE, Bordeaux Sciences Agro, SAVE, ISVV, F-33340, Villenave d'Ornon, France
- Department of Viticulture and Enology, University of California Davis, Davis, 95616, CA, USA
| | - Andrea Minio
- Department of Viticulture and Enology, University of California Davis, Davis, 95616, CA, USA
| | - Pere Mestre
- INRAE, Université de Strasbourg, SVQV, F-68125, Colmar, France
| | - Frédéric Fabre
- INRAE, Bordeaux Sciences Agro, SAVE, ISVV, F-33340, Villenave d'Ornon, France
| | - Isabelle D Mazet
- INRAE, Bordeaux Sciences Agro, SAVE, ISVV, F-33340, Villenave d'Ornon, France
| | - Carole Couture
- INRAE, Bordeaux Sciences Agro, SAVE, ISVV, F-33340, Villenave d'Ornon, France
| | - Fabrice Legeai
- INRAE, IGEPP, F-35650, Le-Rheu, France
- INRIA, IRISA, GenOuest Core Facility, F-35000, Rennes, France
| | | | - Dario Cantu
- Department of Viticulture and Enology, University of California Davis, Davis, 95616, CA, USA
- Genome Center, University of California Davis, Davis, 95616, CA, USA
| | - François Delmotte
- INRAE, Bordeaux Sciences Agro, SAVE, ISVV, F-33340, Villenave d'Ornon, France
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2
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Gouveia C, Santos RB, Paiva-Silva C, Buchholz G, Malhó R, Figueiredo A. The pathogenicity of Plasmopara viticola: a review of evolutionary dynamics, infection strategies and effector molecules. BMC PLANT BIOLOGY 2024; 24:327. [PMID: 38658826 PMCID: PMC11040782 DOI: 10.1186/s12870-024-05037-0] [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: 07/13/2023] [Accepted: 04/17/2024] [Indexed: 04/26/2024]
Abstract
Oomycetes are filamentous organisms that resemble fungi in terms of morphology and life cycle, primarily due to convergent evolution. The success of pathogenic oomycetes lies in their ability to adapt and overcome host resistance, occasionally transitioning to new hosts. During plant infection, these organisms secrete effector proteins and other compounds during plant infection, as a molecular arsenal that contributes to their pathogenic success. Genomic sequencing, transcriptomic analysis, and proteomic studies have revealed highly diverse effector repertoires among different oomycete pathogens, highlighting their adaptability and evolution potential.The obligate biotrophic oomycete Plasmopara viticola affects grapevine plants (Vitis vinifera L.) causing the downy mildew disease, with significant economic impact. This disease is devastating in Europe, leading to substantial production losses. Even though Plasmopara viticola is a well-known pathogen, to date there are scarce reviews summarising pathogenicity, virulence, the genetics and molecular mechanisms of interaction with grapevine.This review aims to explore the current knowledge of the infection strategy, lifecycle, effector molecules, and pathogenicity of Plasmopara viticola. The recent sequencing of the Plasmopara viticola genome has provided new insights into understanding the infection strategies employed by this pathogen. Additionally, we will highlight the contributions of omics technologies in unravelling the ongoing evolution of this oomycete, including the first in-plant proteome analysis of the pathogen.
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Affiliation(s)
- Catarina Gouveia
- Biosystems and Integrative Sciences Institute (BioISI), Faculty of Science, University of Lisbon, Lisboa, Portugal
| | - Rita B Santos
- Biosystems and Integrative Sciences Institute (BioISI), Faculty of Science, University of Lisbon, Lisboa, Portugal
| | - Catarina Paiva-Silva
- Biosystems and Integrative Sciences Institute (BioISI), Faculty of Science, University of Lisbon, Lisboa, Portugal
| | - Günther Buchholz
- RLP AgroScience/AlPlanta-Institute for Plant Research, Neustadt an Der Weinstrasse, Germany
| | - Rui Malhó
- Biosystems and Integrative Sciences Institute (BioISI), Faculty of Science, University of Lisbon, Lisboa, Portugal
| | - Andreia Figueiredo
- Biosystems and Integrative Sciences Institute (BioISI), Faculty of Science, University of Lisbon, Lisboa, Portugal.
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3
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Sabnam N, Hussain A, Saha P. The secret password: Cell death-inducing proteins in filamentous phytopathogens - As versatile tools to develop disease-resistant crops. Microb Pathog 2023; 183:106276. [PMID: 37541554 DOI: 10.1016/j.micpath.2023.106276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 07/25/2023] [Accepted: 07/27/2023] [Indexed: 08/06/2023]
Abstract
Cell death-inducing proteins (CDIPs) are some of the secreted effector proteins manifested by filamentous oomycetes and fungal pathogens to invade the plant tissue and facilitate infection. Along with their involvement in different developmental processes and virulence, CDIPs play a crucial role in plant-pathogen interactions. As the name implies, CDIPs cause necrosis and trigger localised cell death in the infected host tissues by the accumulation of higher concentrations of hydrogen peroxide (H2O2), oxidative burst, accumulation of nitric oxide (NO), and electrolyte leakage. They also stimulate the biosynthesis of defense-related phytohormones such as salicylic acid (SA), jasmonic acid (JA), abscisic acid (ABA), and ethylene (ET), as well as the expression of pathogenesis-related (PR) genes that are important in disease resistance. Altogether, the interactions result in the hypersensitive response (HR) in the host plant, which might confer systemic acquired resistance (SAR) in some cases against a vast array of related and unrelated pathogens. The CDIPs, due to their capability of inducing host resistance, are thus unique among the array of proteins secreted by filamentous plant pathogens. More interestingly, a few transgenic plant lines have also been developed expressing the CDIPs with added resistance. Thus, CDIPs have opened an interesting hot area of research. The present study critically reviews the current knowledge of major types of CDIPs identified across filamentous phytopathogens and their modes of action in the last couple of years. This review also highlights the recent breakthrough technologies in studying plant-pathogen interactions as well as crop improvement by enhancing disease resistance through CDIPs.
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Affiliation(s)
- Nazmiara Sabnam
- Department of Life Sciences, Presidency University, Kolkata, India.
| | - Afzal Hussain
- Department of Bioinformatics, Maulana Azad National Institute of Technology, Bhopal, India
| | - Pallabi Saha
- Biotechnology Institute, University of Minnesota, Saint Paul, Minnesota, 55108, United States; Department of Biotechnology, National Institute of Technology, Durgapur, India
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4
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Combier M, Evangelisti E, Piron MC, Schornack S, Mestre P. Candidate effector proteins from the oomycetes Plasmopara viticola and Phytophthora parasitica share similar predicted structures and induce cell death in Nicotiana species. PLoS One 2022; 17:e0278778. [PMID: 36459530 PMCID: PMC9718384 DOI: 10.1371/journal.pone.0278778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 11/22/2022] [Indexed: 12/04/2022] Open
Abstract
Effector proteins secreted by plant pathogens are essential for infection. Cytoplasmic RXLR effectors from oomycetes are characterized by the presence of RXLR and EER motifs that are frequently linked to WY- and/or LWY-domains, folds that are exclusive to this effector family. A related family of secreted candidate effector proteins, carrying WY-domains and the EER motif but lacking the canonical RXLR motif, has recently been described in oomycetes and is mainly found in downy mildew pathogens. Plasmopara viticola is an obligate biotrophic oomycete causing grapevine downy mildew. Here we describe a conserved Pl. viticola secreted candidate non-RXLR effector protein with cell death-inducing activity in Nicotiana species. A similar RXLR effector candidate from the broad host range oomycete pathogen Phytophthora parasitica also induces cell death in Nicotiana. Through comparative tertiary structure modelling, we reveal that both proteins are predicted to carry WY- and LWY-domains. Our work supports the presence of LWY-domains in non-RXLR effectors and suggests that effector candidates with similar domain architecture may exert similar activities.
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Affiliation(s)
- Maud Combier
- SVQV, UMR-A 1131, Université de Strasbourg, INRAE, Colmar, France
| | - Edouard Evangelisti
- Sainsbury Laboratory (SLCU), University of Cambridge, Cambridge, United Kingdom
| | | | - Sebastian Schornack
- Sainsbury Laboratory (SLCU), University of Cambridge, Cambridge, United Kingdom
| | - Pere Mestre
- SVQV, UMR-A 1131, Université de Strasbourg, INRAE, Colmar, France
- * E-mail:
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5
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The molecular dialog between oomycete effectors and their plant and animal hosts. FUNGAL BIOL REV 2022. [DOI: 10.1016/j.fbr.2022.10.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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6
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Yin X, Fu Q, Shang B, Wang Y, Liu R, Chen T, Xiang G, Dou M, Liu G, Xu Y. An RxLR effector from Plasmopara viticola suppresses plant immunity in grapevine by targeting and stabilizing VpBPA1. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 112:104-114. [PMID: 35929367 DOI: 10.1111/tpj.15933] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 07/25/2022] [Accepted: 08/01/2022] [Indexed: 06/15/2023]
Abstract
Grapevine downy mildew, caused by Plasmopara viticola, is one of the most devastating diseases in viticulture. Plasmopara viticola secretes RxLR effectors to modulate immune responses in grapevine. Here, we report an RxLR effector RxLR50253 from P. viticola that can interfere with plant immune response and thus promote pathogen colonization. RxLR50253 was induced at an early stage of P. viticola infection and could suppress elicitor (INF1 and Bax)-triggered cell death. RxLR50253 promote pathogen colonization in both tobacco and grapevine leaves. VpBPA1 was found to be the host target of RxLR50253 by yeast two-hybrid screening, and interaction between RxLR50253 and VpBPA1 was confirmed by multiple in vivo and in vitro assays. Further analysis revealed that VpBPA1 promoted pathogen colonization and decreased H2 O2 accumulation in transgenic tobacco and grapevine, while there was enhanced resistance and H2 O2 accumulation in NbBPA1-silenced Nicotiana benthamiana leaves. Moreover, transient expression of VpBPA1 in NbBPA1-silenced N. benthamiana leaves could reduce the accumulation of H2 O2 . Experiments in vivo demonstrated that RxLR50253 inhibits degradation of VpBPA1. Taken together, our findings showed that RxLR50253 targets and stabilizes VpBPA1 to attenuate plant immunity through decreasing H2 O2 accumulation during pathogen infection.
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Affiliation(s)
- Xiao Yin
- State Key Laboratory of Crop Stress Biology in Arid Areas (Northwest A&F University) Yangling, Shaanxi, People's Republic of China
- College of Horticulture, Northwest A&F University, Yangling, Shaanxi, People's Republic of China
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Yangling, Shaanxi, People's Republic of China
| | - Qingqing Fu
- State Key Laboratory of Crop Stress Biology in Arid Areas (Northwest A&F University) Yangling, Shaanxi, People's Republic of China
- College of Horticulture, Northwest A&F University, Yangling, Shaanxi, People's Republic of China
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Yangling, Shaanxi, People's Republic of China
| | - Boxing Shang
- State Key Laboratory of Crop Stress Biology in Arid Areas (Northwest A&F University) Yangling, Shaanxi, People's Republic of China
- College of Horticulture, Northwest A&F University, Yangling, Shaanxi, People's Republic of China
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Yangling, Shaanxi, People's Republic of China
| | - Yunlei Wang
- State Key Laboratory of Crop Stress Biology in Arid Areas (Northwest A&F University) Yangling, Shaanxi, People's Republic of China
- College of Horticulture, Northwest A&F University, Yangling, Shaanxi, People's Republic of China
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Yangling, Shaanxi, People's Republic of China
| | - Ruiqi Liu
- State Key Laboratory of Crop Stress Biology in Arid Areas (Northwest A&F University) Yangling, Shaanxi, People's Republic of China
- College of Horticulture, Northwest A&F University, Yangling, Shaanxi, People's Republic of China
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Yangling, Shaanxi, People's Republic of China
| | - Tingting Chen
- State Key Laboratory of Crop Stress Biology in Arid Areas (Northwest A&F University) Yangling, Shaanxi, People's Republic of China
- College of Horticulture, Northwest A&F University, Yangling, Shaanxi, People's Republic of China
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Yangling, Shaanxi, People's Republic of China
| | - Gaoqing Xiang
- State Key Laboratory of Crop Stress Biology in Arid Areas (Northwest A&F University) Yangling, Shaanxi, People's Republic of China
- College of Horticulture, Northwest A&F University, Yangling, Shaanxi, People's Republic of China
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Yangling, Shaanxi, People's Republic of China
| | - Mengru Dou
- State Key Laboratory of Crop Stress Biology in Arid Areas (Northwest A&F University) Yangling, Shaanxi, People's Republic of China
- College of Horticulture, Northwest A&F University, Yangling, Shaanxi, People's Republic of China
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Yangling, Shaanxi, People's Republic of China
| | - Guotian Liu
- State Key Laboratory of Crop Stress Biology in Arid Areas (Northwest A&F University) Yangling, Shaanxi, People's Republic of China
- College of Horticulture, Northwest A&F University, Yangling, Shaanxi, People's Republic of China
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Yangling, Shaanxi, People's Republic of China
| | - Yan Xu
- State Key Laboratory of Crop Stress Biology in Arid Areas (Northwest A&F University) Yangling, Shaanxi, People's Republic of China
- College of Horticulture, Northwest A&F University, Yangling, Shaanxi, People's Republic of China
- Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Yangling, Shaanxi, People's Republic of China
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7
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Chepsergon J, Motaung TE, Moleleki LN. "Core" RxLR effectors in phytopathogenic oomycetes: A promising way to breeding for durable resistance in plants? Virulence 2021; 12:1921-1935. [PMID: 34304703 PMCID: PMC8516161 DOI: 10.1080/21505594.2021.1948277] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 06/11/2021] [Accepted: 06/18/2021] [Indexed: 12/30/2022] Open
Abstract
Phytopathogenic oomycetes are known to successfully infect their hosts due to their ability to secrete effector proteins. Of interest to many researchers are effectors with the N-terminal RxLR motif (Arginine-any amino acid-Leucine-Arginine). Owing to advances in genome sequencing, we can now comprehend the high level of diversity among oomycete effectors, and similarly, their conservation within and among species referred to here as "core" RxLR effectors (CREs). Currently, there is a considerable number of CREs that have been identified in oomycetes. Functional characterization of these CREs propose their virulence role with the potential of targeting central cellular processes that are conserved across diverse plant species. We reason that effectors that are highly conserved and recognized by the host, could be harnessed in engineering plants for durable as well as broad-spectrum resistance.
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Affiliation(s)
- Jane Chepsergon
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria, Gauteng, South Africa
| | - Thabiso E. Motaung
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria, Gauteng, South Africa
| | - Lucy Novungayo Moleleki
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria, Gauteng, South Africa
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Wood KJ, Nur M, Gil J, Fletcher K, Lakeman K, Gann D, Gothberg A, Khuu T, Kopetzky J, Naqvi S, Pandya A, Zhang C, Maisonneuve B, Pel M, Michelmore R. Effector prediction and characterization in the oomycete pathogen Bremia lactucae reveal host-recognized WY domain proteins that lack the canonical RXLR motif. PLoS Pathog 2020; 16:e1009012. [PMID: 33104763 PMCID: PMC7644090 DOI: 10.1371/journal.ppat.1009012] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 11/05/2020] [Accepted: 09/29/2020] [Indexed: 12/11/2022] Open
Abstract
Pathogens that infect plants and animals use a diverse arsenal of effector proteins to suppress the host immune system and promote infection. Identification of effectors in pathogen genomes is foundational to understanding mechanisms of pathogenesis, for monitoring field pathogen populations, and for breeding disease resistance. We identified candidate effectors from the lettuce downy mildew pathogen Bremia lactucae by searching the predicted proteome for the WY domain, a structural fold found in effectors that has been implicated in immune suppression as well as effector recognition by host resistance proteins. We predicted 55 WY domain containing proteins in the genome of B. lactucae and found substantial variation in both sequence and domain architecture. These candidate effectors exhibit several characteristics of pathogen effectors, including an N-terminal signal peptide, lineage specificity, and expression during infection. Unexpectedly, only a minority of B. lactucae WY effectors contain the canonical N-terminal RXLR motif, which is a conserved feature in the majority of cytoplasmic effectors reported in Phytophthora spp. Functional analysis of 21 effectors containing WY domains revealed 11 that elicited cell death on wild accessions and domesticated lettuce lines containing resistance genes, indicative of recognition of these effectors by the host immune system. Only two of the 11 recognized effectors contained the canonical RXLR motif, suggesting that there has been an evolutionary divergence in sequence motifs between genera; this has major consequences for robust effector prediction in oomycete pathogens.
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Affiliation(s)
- Kelsey J. Wood
- The Genome Center, University of California, Davis, Davis, California, United States of America
- Integrative Genetics & Genomics Graduate Group, University of California, Davis, Davis, California, United States of America
| | - Munir Nur
- The Genome Center, University of California, Davis, Davis, California, United States of America
| | - Juliana Gil
- The Genome Center, University of California, Davis, Davis, California, United States of America
- Plant Pathology Graduate Group, University of California, Davis, Davis, California, United States of America
| | - Kyle Fletcher
- The Genome Center, University of California, Davis, Davis, California, United States of America
| | | | - Dasan Gann
- The Genome Center, University of California, Davis, Davis, California, United States of America
| | - Ayumi Gothberg
- The Genome Center, University of California, Davis, Davis, California, United States of America
| | - Tina Khuu
- The Genome Center, University of California, Davis, Davis, California, United States of America
| | - Jennifer Kopetzky
- The Genome Center, University of California, Davis, Davis, California, United States of America
| | - Sanye Naqvi
- The Genome Center, University of California, Davis, Davis, California, United States of America
| | - Archana Pandya
- The Genome Center, University of California, Davis, Davis, California, United States of America
| | - Chi Zhang
- The Genome Center, University of California, Davis, Davis, California, United States of America
| | | | | | - Richard Michelmore
- The Genome Center, University of California, Davis, Davis, California, United States of America
- Departments of Plant Sciences, Molecular & Cellular Biology, Medical Microbiology & Immunology, University of California, Davis, Davis, California, United States of America
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9
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Purayannur S, Cano LM, Bowman MJ, Childs KL, Gent DH, Quesada-Ocampo LM. The Effector Repertoire of the Hop Downy Mildew Pathogen Pseudoperonospora humuli. Front Genet 2020; 11:910. [PMID: 32849854 PMCID: PMC7432248 DOI: 10.3389/fgene.2020.00910] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 07/22/2020] [Indexed: 01/18/2023] Open
Abstract
Pseudoperonospora humuli is an obligate biotrophic oomycete that causes downy mildew (DM), one of the most destructive diseases of cultivated hop that can lead to 100% crop loss in susceptible cultivars. We used the published genome of P. humuli to predict the secretome and effectorome and analyze the transcriptome variation among diverse isolates and during infection of hop leaves. Mining the predicted coding genes of the sequenced isolate OR502AA of P. humuli revealed a secretome of 1,250 genes. We identified 296 RXLR and RXLR-like effector-encoding genes in the secretome. Among the predicted RXLRs, there were several WY-motif-containing effectors that lacked canonical RXLR domains. Transcriptome analysis of sporangia from 12 different isolates collected from various hop cultivars revealed 754 secreted proteins and 201 RXLR effectors that showed transcript evidence across all isolates with reads per kilobase million (RPKM) values > 0. RNA-seq analysis of OR502AA-infected hop leaf samples at different time points after infection revealed highly expressed effectors that may play a relevant role in pathogenicity. Quantitative RT-PCR analysis confirmed the differential expression of selected effectors. We identified a set of P. humuli core effectors that showed transcript evidence in all tested isolates and elevated expression during infection. These effectors are ideal candidates for functional analysis and effector-assisted breeding to develop DM resistant hop cultivars.
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Affiliation(s)
- Savithri Purayannur
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC, United States
| | - Liliana M. Cano
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC, United States
- Indian River Research and Education Center, Department of Plant Pathology, Institute of Food and Agricultural Sciences, University of Florida, Fort Pierce, FL, United States
| | - Megan J. Bowman
- Department of Plant Biology, Michigan State University, East Lansing, MI, United States
- Ball Horticultural Company, West Chicago, IL, United States
| | - Kevin L. Childs
- Department of Plant Biology, Michigan State University, East Lansing, MI, United States
| | - David H. Gent
- United States Department of Agriculture-Agricultural Research Service, Forage Seed and Cereal Research Unit, Oregon State University, Corvallis, OR, United States
| | - Lina M. Quesada-Ocampo
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC, United States
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