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Xia C, Wang M, Cornejo OE, Jiwan DA, See DR, Chen X. Secretome Characterization and Correlation Analysis Reveal Putative Pathogenicity Mechanisms and Identify Candidate Avirulence Genes in the Wheat Stripe Rust Fungus Puccinia striiformis f. sp. tritici. Front Microbiol 2017; 8:2394. [PMID: 29312156 PMCID: PMC5732408 DOI: 10.3389/fmicb.2017.02394] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2017] [Accepted: 11/20/2017] [Indexed: 12/30/2022] Open
Abstract
Stripe (yellow) rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most destructive diseases of wheat worldwide. Planting resistant cultivars is an effective way to control this disease, but race-specific resistance can be overcome quickly due to the rapid evolving Pst population. Studying the pathogenicity mechanisms is critical for understanding how Pst virulence changes and how to develop wheat cultivars with durable resistance to stripe rust. We re-sequenced 7 Pst isolates and included additional 7 previously sequenced isolates to represent balanced virulence/avirulence profiles for several avirulence loci in seretome analyses. We observed an uneven distribution of heterozygosity among the isolates. Secretome comparison of Pst with other rust fungi identified a large portion of species-specific secreted proteins, suggesting that they may have specific roles when interacting with the wheat host. Thirty-two effectors of Pst were identified from its secretome. We identified candidates for Avr genes corresponding to six Yr genes by correlating polymorphisms for effector genes to the virulence/avirulence profiles of the 14 Pst isolates. The putative AvYr76 was present in the avirulent isolates, but absent in the virulent isolates, suggesting that deleting the coding region of the candidate avirulence gene has produced races virulent to resistance gene Yr76. We conclude that incorporating avirulence/virulence phenotypes into correlation analysis with variations in genomic structure and secretome, particularly presence/absence polymorphisms of effectors, is an efficient way to identify candidate Avr genes in Pst. The candidate effector genes provide a rich resource for further studies to determine the evolutionary history of Pst populations and the co-evolutionary arms race between Pst and wheat. The Avr candidates identified in this study will lead to cloning avirulence genes in Pst, which will enable us to understand molecular mechanisms underlying Pst-wheat interactions, to determine the effectiveness of resistance genes and further to develop durable resistance to stripe rust.
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Affiliation(s)
- Chongjing Xia
- Department of Plant Pathology, Washington State University, Pullman, WA, United States
| | - Meinan Wang
- Department of Plant Pathology, Washington State University, Pullman, WA, United States
| | - Omar E. Cornejo
- School of Biological Sciences, Washington State University, Pullman, WA, United States
| | - Derick A. Jiwan
- Wheat Health, Genetics, and Quality Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Pullman, WA, United States
| | - Deven R. See
- Department of Plant Pathology, Washington State University, Pullman, WA, United States
- Wheat Health, Genetics, and Quality Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Pullman, WA, United States
| | - Xianming Chen
- Department of Plant Pathology, Washington State University, Pullman, WA, United States
- Wheat Health, Genetics, and Quality Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Pullman, WA, United States
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Xia Y, Fei B, He J, Zhou M, Zhang D, Pan L, Li S, Liang Y, Wang L, Zhu J, Li P, Zheng A. Transcriptome analysis reveals the host selection fitness mechanisms of the Rhizoctonia solani AG1IA pathogen. Sci Rep 2017; 7:10120. [PMID: 28860554 PMCID: PMC5579035 DOI: 10.1038/s41598-017-10804-1] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Accepted: 08/15/2017] [Indexed: 11/12/2022] Open
Abstract
Rhizoctonia solani AG1IA is a major generalist pathogen that causes sheath blight. Its genome, which was the first to be sequenced from the Rhizoctonia genus, may serve as a model for studying pathogenic mechanisms. To explore the pathogen-host fitness mechanism of sheath-blight fungus, a comprehensive comparative transcriptome ecotype analysis of R. solani AG1IA isolated from rice, soybean and corn during infection was performed. Special characteristics in gene expression, gene ontology terms and expression of pathogenesis-associated genes, including genes encoding secreted proteins, candidate effectors, hydrolases, and proteins involved in secondary metabolite production and the MAPK pathway, were revealed. Furthermore, as an important means of pathogenic modulation, diverse alternative splicing of key pathogenic genes in Rhizoctonia solani AG1IA during infections of the abovementioned hosts was uncovered for the first time. These important findings of key factors in the pathogenicity of R. solani AG1IA ecotypes during infection of various hosts explain host preference and provide novel insights into the pathogenic mechanisms and host-pathogen selection. Furthermore, they provide information on the fitness of Rhizoctonia, a severe pathogen with a wide host range.
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Affiliation(s)
- Yuan Xia
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
- Key Laboratory of Sichuan Crop Major Diseases, Sichuan Agricultural University, Chengdu, 611130, China
| | - Binghong Fei
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
- Key Laboratory of Sichuan Crop Major Diseases, Sichuan Agricultural University, Chengdu, 611130, China
| | - Jiayu He
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
- Key Laboratory of Sichuan Crop Major Diseases, Sichuan Agricultural University, Chengdu, 611130, China
| | - Menglin Zhou
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
- Key Laboratory of Sichuan Crop Major Diseases, Sichuan Agricultural University, Chengdu, 611130, China
| | - Danhua Zhang
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
- Key Laboratory of Sichuan Crop Major Diseases, Sichuan Agricultural University, Chengdu, 611130, China
| | - Linxiu Pan
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
- Key Laboratory of Sichuan Crop Major Diseases, Sichuan Agricultural University, Chengdu, 611130, China
| | - Shuangcheng Li
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
- Key Laboratory of Southwest Corp Gene Resource and Genetic Improvement of Ministry of Education, Sichuan Agricultural University, Ya'an, 625014, China
| | - Yueyang Liang
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
- Key Laboratory of Southwest Corp Gene Resource and Genetic Improvement of Ministry of Education, Sichuan Agricultural University, Ya'an, 625014, China
| | - Lingxia Wang
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
- Key Laboratory of Southwest Corp Gene Resource and Genetic Improvement of Ministry of Education, Sichuan Agricultural University, Ya'an, 625014, China
| | - Jianqing Zhu
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
- Key Laboratory of Southwest Corp Gene Resource and Genetic Improvement of Ministry of Education, Sichuan Agricultural University, Ya'an, 625014, China
| | - Ping Li
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
- Key Laboratory of Southwest Corp Gene Resource and Genetic Improvement of Ministry of Education, Sichuan Agricultural University, Ya'an, 625014, China
| | - Aiping Zheng
- Rice Research Institute, Sichuan Agricultural University, Chengdu, 611130, China.
- Key Laboratory of Sichuan Crop Major Diseases, Sichuan Agricultural University, Chengdu, 611130, China.
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Tao SQ, Cao B, Tian CM, Liang YM. Comparative transcriptome analysis and identification of candidate effectors in two related rust species (Gymnosporangium yamadae and Gymnosporangium asiaticum). BMC Genomics 2017; 18:651. [PMID: 28830353 PMCID: PMC5567642 DOI: 10.1186/s12864-017-4059-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Accepted: 08/14/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Rust fungi constitute the largest group of plant fungal pathogens. However, a paucity of data, including genomic sequences, transcriptome sequences, and associated molecular markers, hinders the development of inhibitory compounds and prevents their analysis from an evolutionary perspective. Gymnosporangium yamadae and G. asiaticum are two closely related rust fungal species, which are ecologically and economically important pathogens that cause apple rust and pear rust, respectively, proved to be devastating to orchards. In this study, we investigated the transcriptomes of these two Gymnosporangium species during the telial stage of their lifecycles. The aim of this study was to understand the evolutionary patterns of these two related fungi and to identify genes that developed by selection. RESULTS The transcriptomes of G. yamadae and G. asiaticum were generated from a mixture of RNA from three biological replicates of each species. We obtained 49,318 and 54,742 transcripts, with N50 values of 1957 and 1664, for G. yamadae and G. asiaticum, respectively. We also identified a repertoire of candidate effectors and other gene families associated with pathogenicity. A total of 4947 pairs of putative orthologues between the two species were identified. Estimation of the non-synonymous/synonymous substitution rate ratios for these orthologues identified 116 pairs with Ka/Ks values greater than1 that are under positive selection and 170 pairs with Ka/Ks values of 1 that are under neutral selection, whereas the remaining 4661 genes are subjected to purifying selection. We estimate that the divergence time between the two species is approximately 5.2 Mya. CONCLUSION This study constitutes a de novo assembly and comparative analysis between the transcriptomes of the two rust species G. yamadae and G. asiaticum. The results identified several orthologous genes, and many expressed genes were identified by annotation. Our analysis of Ka/Ks ratios identified orthologous genes subjected to positive or purifying selection. An evolutionary analysis of these two species provided a relatively precise divergence time. Overall, the information obtained in this study increases the genetic resources available for research on the genetic diversity of the Gymnosporangium genus.
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Affiliation(s)
- Si-Qi Tao
- The Key Laboratory for Silviculture and Conservation of Ministry of Education, Beijing Forestry University, Beijing, 100083, China
| | - Bin Cao
- The Key Laboratory for Silviculture and Conservation of Ministry of Education, Beijing Forestry University, Beijing, 100083, China
| | - Cheng-Ming Tian
- The Key Laboratory for Silviculture and Conservation of Ministry of Education, Beijing Forestry University, Beijing, 100083, China
| | - Ying-Mei Liang
- Museum of Beijing Forestry University, Beijing, 100083, China.
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Dagvadorj B, Ozketen AC, Andac A, Duggan C, Bozkurt TO, Akkaya MS. A Puccinia striiformis f. sp. tritici secreted protein activates plant immunity at the cell surface. Sci Rep 2017; 7:1141. [PMID: 28442716 PMCID: PMC5430700 DOI: 10.1038/s41598-017-01100-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Accepted: 03/24/2017] [Indexed: 01/02/2023] Open
Abstract
Pathogens secrete effector proteins to suppress host immunity, mediate nutrient uptake and subsequently enable parasitism. However, on non-adapted hosts, effectors can be detected as non-self by host immune receptors and activate non-host immunity. Nevertheless, the molecular mechanisms of effector triggered non-host resistance remain unknown. Here, we report that a small cysteine-rich protein PstSCR1 from the wheat rust pathogen Puccinia striiformis f. sp. tritici (Pst) activates immunity in the non-host solanaceous model plant Nicotiana benthamiana. PstSCR1 homologs were found to be conserved in Pst, and in its closest relatives, Puccinia graminis f. sp. tritici and Puccinia triticina. When PstSCR1 was expressed in N. benthamiana with its signal peptide, it provoked the plant immune system, whereas no stimulation was observed when it was expressed without its signal peptide. PstSCR1 expression in N. benthamiana significantly reduced infection capacity of the oomycete pathogens. Moreover, apoplast-targeted PstSCR1 triggered plant cell death in a dose dependent manner. However, in Brassinosteroid insensitive 1-Associated Kinase 1 (SERK3/BAK1) silenced N. benthamiana, cell death was remarkably decreased. Finally, purified PstSCR1 protein activated defence related gene expression in N. benthamiana. Our results show that a Pst-secreted protein, PstSCR1 can activate surface mediated immunity in non-adapted hosts and contribute to non-host resistance.
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Affiliation(s)
- Bayantes Dagvadorj
- Middle East Technical University, Biotechnology Program, Department of Chemistry, Dumlupinar Blvd., Cankaya, Ankara, TR-06800, Turkey
| | - Ahmet Caglar Ozketen
- Middle East Technical University, Biotechnology Program, Department of Chemistry, Dumlupinar Blvd., Cankaya, Ankara, TR-06800, Turkey
| | - Ayse Andac
- Middle East Technical University, Biotechnology Program, Department of Chemistry, Dumlupinar Blvd., Cankaya, Ankara, TR-06800, Turkey
| | - Cian Duggan
- Imperial College London, Department of Life Sciences, London, SW7 2AZ, UK
| | | | - Mahinur S Akkaya
- Middle East Technical University, Biotechnology Program, Department of Chemistry, Dumlupinar Blvd., Cankaya, Ankara, TR-06800, Turkey.
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Cheng Y, Wu K, Yao J, Li S, Wang X, Huang L, Kang Z. PSTha5a23, a candidate effector from the obligate biotrophic pathogen Puccinia striiformis f. sp. tritici, is involved in plant defense suppression and rust pathogenicity. Environ Microbiol 2017; 19:1717-1729. [PMID: 27871149 DOI: 10.1111/1462-2920.13610] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 11/16/2016] [Indexed: 11/26/2022]
Abstract
During the infection of host plants, pathogens can deliver virulence-associated 'effector' proteins to promote plant susceptibility. However, little is known about effector function in the obligate biotrophic pathogen Puccinia striiformis f. sp. tritici (Pst) that is an important fungal pathogen in wheat production worldwide. Here, they report their findings on an in planta highly induced candidate effector from Pst, PSTha5a23. The PSTha5a23 gene is unique to Pst and shows a low level of intra-species polymorphism. It has a functional N-terminal signal peptide and is translocated to the host cytoplasm after infection. Overexpression of PSTha5a23 in Nicotiana benthamiana was found to suppress the programmed cell death triggered by BAX, PAMP-INF1 and two resistance-related mitogen-activated protein kinases (MKK1 and NPK1). Overexpression of PSTha5a23 in wheat also suppressed pattern-triggered immunity (PTI)-associated callose deposition. In addition, silencing of PSTha5a23 did not change Pst virulence phenotypes; however, overexpression of PSTha5a23 significantly enhanced Pst virulence in wheat. These results indicate that the Pst candidate effector PSTha5a23 plays an important role in plant defense suppression and rust pathogenicity, and also highlight the utility of gene overexpression in plants as a tool for studying effectors from obligate biotrophic pathogens.
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Affiliation(s)
- Yulin Cheng
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Life Sciences, Northwest A&F University, Shaanxi, Yangling, 712100, China
| | - Kuan Wu
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Shaanxi, Yangling, 712100, China
| | - Juanni Yao
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Shaanxi, Yangling, 712100, China
| | - Shumin Li
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Shaanxi, Yangling, 712100, China
| | - Xiaojie Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Shaanxi, Yangling, 712100, China
| | - Lili Huang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Shaanxi, Yangling, 712100, China
| | - Zhensheng Kang
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Shaanxi, Yangling, 712100, China
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Comparative Analysis Highlights Variable Genome Content of Wheat Rusts and Divergence of the Mating Loci. G3-GENES GENOMES GENETICS 2017; 7:361-376. [PMID: 27913634 PMCID: PMC5295586 DOI: 10.1534/g3.116.032797] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Three members of the Puccinia genus, Pucciniatriticina (Pt), Pstriiformis f.sp. tritici (Pst), and Pgraminis f.sp. tritici (Pgt), cause the most common and often most significant foliar diseases of wheat. While similar in biology and life cycle, each species is uniquely adapted and specialized. The genomes of Pt and Pst were sequenced and compared to that of Pgt to identify common and distinguishing gene content, to determine gene variation among wheat rust pathogens, other rust fungi, and basidiomycetes, and to identify genes of significance for infection. Pt had the largest genome of the three, estimated at 135 Mb with expansion due to mobile elements and repeats encompassing 50.9% of contig bases; in comparison, repeats occupy 31.5% for Pst and 36.5% for Pgt We find all three genomes are highly heterozygous, with Pst [5.97 single nucleotide polymorphisms (SNPs)/kb] nearly twice the level detected in Pt (2.57 SNPs/kb) and that previously reported for Pgt Of 1358 predicted effectors in Pt, 784 were found expressed across diverse life cycle stages including the sexual stage. Comparison to related fungi highlighted the expansion of gene families involved in transcriptional regulation and nucleotide binding, protein modification, and carbohydrate degradation enzymes. Two allelic homeodomain pairs, HD1 and HD2, were identified in each dikaryotic Puccinia species along with three pheromone receptor (STE3) mating-type genes, two of which are likely representing allelic specificities. The HD proteins were active in a heterologous Ustilago maydis mating assay and host-induced gene silencing (HIGS) of the HD and STE3 alleles reduced wheat host infection.
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Kamel L, Tang N, Malbreil M, San Clemente H, Le Marquer M, Roux C, Frei dit Frey N. The Comparison of Expressed Candidate Secreted Proteins from Two Arbuscular Mycorrhizal Fungi Unravels Common and Specific Molecular Tools to Invade Different Host Plants. FRONTIERS IN PLANT SCIENCE 2017; 8:124. [PMID: 28223991 PMCID: PMC5293756 DOI: 10.3389/fpls.2017.00124] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 01/20/2017] [Indexed: 05/19/2023]
Abstract
Arbuscular mycorrhizal fungi (AMF), belonging to the fungal phylum Glomeromycota, form mutualistic symbioses with roots of almost 80% of land plants. The release of genomic data from the ubiquitous AMF Rhizophagus irregularis revealed that this species possesses a large set of putative secreted proteins (RiSPs) that could be of major importance for establishing the symbiosis. In the present study, we aimed to identify SPs involved in the establishment of AM symbiosis based on comparative gene expression analyses. We first curated the secretome of the R. irregularis DAOM 197198 strain based on two available genomic assemblies. Then we analyzed the expression patterns of the putative RiSPs obtained from the fungus in symbiotic association with three phylogenetically distant host plants-a monocot, a dicot and a liverwort-in comparison with non-symbiotic stages. We found that 33 out of 84 RiSPs induced in planta were commonly up-regulated in these three hosts. Most of these common RiSPs are small proteins of unknown function that may represent putative host non-specific effector proteins. We further investigated the expressed secretome of Gigaspora rosea, an AM fungal species phylogenetically distant from R. irregularis. G. rosea also presents original symbiotic features, a narrower host spectrum and a restrictive geographic distribution compared to R. irregularis. Interestingly, when analyzing up-regulated G. rosea SPs (GrSPs) in different hosts, a higher ratio of host-specific GrSPs was found compared to RiSPs. Such difference of expression patterns may mirror the restrained host spectrum of G. rosea compared to R. irregularis. Finally, we identified a set of conserved SPs, commonly up-regulated by both fungi in all hosts tested, that could correspond to common keys of AMF to colonize host plants. Our data thus highlight the specificities of two distant AM fungi and help in understanding their conserved and specific strategies to invade different hosts.
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Affiliation(s)
- Laurent Kamel
- Laboratoire de Recherche en Sciences Végétales, Université Paul Sabatier - Université de Toulouse, Centre National de la Recherche ScientifiqueCastanet-Tolosan, France
- Agronutrition, Laboratoire de BiotechnologiesLabege, France
| | - Nianwu Tang
- Laboratoire de Recherche en Sciences Végétales, Université Paul Sabatier - Université de Toulouse, Centre National de la Recherche ScientifiqueCastanet-Tolosan, France
| | - Mathilde Malbreil
- Laboratoire de Recherche en Sciences Végétales, Université Paul Sabatier - Université de Toulouse, Centre National de la Recherche ScientifiqueCastanet-Tolosan, France
| | - Hélène San Clemente
- Laboratoire de Recherche en Sciences Végétales, Université Paul Sabatier - Université de Toulouse, Centre National de la Recherche ScientifiqueCastanet-Tolosan, France
| | - Morgane Le Marquer
- Laboratoire de Recherche en Sciences Végétales, Université Paul Sabatier - Université de Toulouse, Centre National de la Recherche ScientifiqueCastanet-Tolosan, France
| | - Christophe Roux
- Laboratoire de Recherche en Sciences Végétales, Université Paul Sabatier - Université de Toulouse, Centre National de la Recherche ScientifiqueCastanet-Tolosan, France
| | - Nicolas Frei dit Frey
- Laboratoire de Recherche en Sciences Végétales, Université Paul Sabatier - Université de Toulouse, Centre National de la Recherche ScientifiqueCastanet-Tolosan, France
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Phylogenetics and Phylogenomics of Rust Fungi. FUNGAL PHYLOGENETICS AND PHYLOGENOMICS 2017; 100:267-307. [DOI: 10.1016/bs.adgen.2017.09.011] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Characterization and comparative analysis of the genome of Puccinia sorghi Schwein, the causal agent of maize common rust. Fungal Genet Biol 2016; 112:31-39. [PMID: 27746189 DOI: 10.1016/j.fgb.2016.10.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 08/17/2016] [Accepted: 10/03/2016] [Indexed: 01/25/2023]
Abstract
Rust fungi are one of the most devastating pathogens of crop plants. The biotrophic fungus Puccinia sorghi Schwein (Ps) is responsible for maize common rust, an endemic disease of maize (Zea mays L.) in Argentina that causes significant yield losses in corn production. In spite of this, the Ps genomic sequence was not available. We used Illumina sequencing to rapidly produce the 99.6Mbdraft genome sequence of Ps race RO10H11247, derived from a single-uredinial isolate from infected maize leaves collected in the Argentine Corn Belt Region during 2010. High quality reads were obtained from 200bppaired-end and 5000bpmate-paired libraries and assembled in 15,722 scaffolds. A pipeline which combined an ab initio program with homology-based models and homology to in planta enriched ESTs from four cereal pathogenic fungus (the three sequenced wheat rusts and Ustilago maydis) was used to identify 21,087 putative coding sequences, of which 1599 might be part of the Ps RO10H11247 secretome. Among the 458 highly conserved protein families from the euKaryotic Orthologous Groups (KOG) that occur in a wide range of eukaryotic organisms, 97.5% have at least one member with high homology in the Ps assembly (TBlastN, E-value⩽e-10) covering more than 50% of the length of the KOG protein. Comparative studies with the three sequenced wheat rust fungus, and microsynteny analysis involving Puccinia striiformis f. sp. tritici (Pst, wheat stripe rust fungus), support the quality achieved. The results presented here show the effectiveness of the Illumina strategy for sequencing dikaryotic genomes of non-model organisms and provides reliable DNA sequence information for genomic studies, including pathogenic mechanisms of this maize fungus and molecular marker design.
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60
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Qi M, Link TI, Müller M, Hirschburger D, Pudake RN, Pedley KF, Braun E, Voegele RT, Baum TJ, Whitham SA. A Small Cysteine-Rich Protein from the Asian Soybean Rust Fungus, Phakopsora pachyrhizi, Suppresses Plant Immunity. PLoS Pathog 2016; 12:e1005827. [PMID: 27676173 PMCID: PMC5038961 DOI: 10.1371/journal.ppat.1005827] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2015] [Accepted: 07/26/2016] [Indexed: 11/25/2022] Open
Abstract
The Asian soybean rust fungus, Phakopsora pachyrhizi, is an obligate biotrophic pathogen causing severe soybean disease epidemics. Molecular mechanisms by which P. pachyrhizi and other rust fungi interact with their host plants are poorly understood. The genomes of all rust fungi encode many small, secreted cysteine-rich proteins (SSCRP). While these proteins are thought to function within the host, their roles are completely unknown. Here, we present the characterization of P. pachyrhizi effector candidate 23 (PpEC23), a SSCRP that we show to suppress plant immunity. Furthermore, we show that PpEC23 interacts with soybean transcription factor GmSPL12l and that soybean plants in which GmSPL12l is silenced have constitutively active immunity, thereby identifying GmSPL12l as a negative regulator of soybean defenses. Collectively, our data present evidence for a virulence function of a rust SSCRP and suggest that PpEC23 is able to suppress soybean immune responses and physically interact with soybean transcription factor GmSPL12l, a negative immune regulator.
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Affiliation(s)
- Mingsheng Qi
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, Iowa, United States of America
| | - Tobias I. Link
- Institut für Phytomedizin, Universität Hohenheim, Stuttgart, Germany
| | - Manuel Müller
- Institut für Phytomedizin, Universität Hohenheim, Stuttgart, Germany
| | | | - Ramesh N. Pudake
- Amity Institute of Nanotechnology, Amity University Uttar Pradesh, Noida, India
| | - Kerry F. Pedley
- Foreign Disease-Weed Science Research Unit, United States Department of Agriculture–Agricultural Research Service, Ft. Detrick, Maryland, United States of America
| | - Edward Braun
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, Iowa, United States of America
| | - Ralf T. Voegele
- Institut für Phytomedizin, Universität Hohenheim, Stuttgart, Germany
| | - Thomas J. Baum
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, Iowa, United States of America
| | - Steven A. Whitham
- Department of Plant Pathology and Microbiology, Iowa State University, Ames, Iowa, United States of America
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Selin C, de Kievit TR, Belmonte MF, Fernando WGD. Elucidating the Role of Effectors in Plant-Fungal Interactions: Progress and Challenges. Front Microbiol 2016; 7:600. [PMID: 27199930 PMCID: PMC4846801 DOI: 10.3389/fmicb.2016.00600] [Citation(s) in RCA: 127] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2016] [Accepted: 04/11/2016] [Indexed: 11/13/2022] Open
Abstract
Pathogenic fungi have diverse growth lifestyles that support fungal colonization on plants. Successful colonization and infection for all lifestyles depends upon the ability to modify living host plants to sequester the necessary nutrients required for growth and reproduction. Secretion of virulence determinants referred to as “effectors” is assumed to be the key governing factor that determines host infection and colonization. Effector proteins are capable of suppressing plant defense responses and alter plant physiology to accommodate fungal invaders. This review focuses on effector molecules of biotrophic and hemibiotrophic plant pathogenic fungi, and the mechanism required for the release and uptake of effector molecules by the fungi and plant cells, respectively. We also place emphasis on the discovery of effectors, difficulties associated with predicting the effector repertoire, and fungal genomic features that have helped promote effector diversity leading to fungal evolution. We discuss the role of specific effectors found in biotrophic and hemibiotrophic fungi and examine how CRISPR/Cas9 technology may provide a new avenue for accelerating our ability in the discovery of fungal effector function.
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Affiliation(s)
- Carrie Selin
- Department of Plant Science, University of Manitoba Winnipeg, MB, Canada
| | | | - Mark F Belmonte
- Department of Biological Sciences, University of Manitoba Winnipeg, MB, Canada
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Kunjeti SG, Iyer G, Johnson E, Li E, Broglie KE, Rauscher G, Rairdan GJ. Identification of Phakopsora pachyrhizi Candidate Effectors with Virulence Activity in a Distantly Related Pathosystem. FRONTIERS IN PLANT SCIENCE 2016; 7:269. [PMID: 27014295 PMCID: PMC4781881 DOI: 10.3389/fpls.2016.00269] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Accepted: 02/21/2016] [Indexed: 05/26/2023]
Abstract
Phakopsora pachyrhizi is the causal agent of Asian Soybean Rust, a disease that causes enormous economic losses, most markedly in South America. P. pachyrhizi is a biotrophic pathogen that utilizes specialized feeding structures called haustoria to colonize its hosts. In rusts and other filamentous plant pathogens, haustoria have been shown to secrete effector proteins into their hosts to permit successful completion of their life cycle. We have constructed a cDNA library from P. pachyrhizi haustoria using paramagnetic bead-based methodology and have identified 35 P. pachyrhizi candidate effector (CE) genes from this library which are described here. In addition, we quantified the transcript expression pattern of six of these genes and show that two of these CEs are able to greatly increase the susceptibility of Nicotiana benthamiana to Phytophthora infestans. This strongly suggests that these genes play an important role in P. pachyrhizi virulence on its hosts.
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Secreted protein gene derived-single nucleotide polymorphisms (SP-SNPs) reveal population diversity and differentiation of Puccinia striiformis f. sp. tritici in the United States. Fungal Biol 2016; 120:729-44. [PMID: 27109369 DOI: 10.1016/j.funbio.2016.02.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2015] [Revised: 02/18/2016] [Accepted: 02/23/2016] [Indexed: 11/21/2022]
Abstract
Single nucleotide polymorphism (SNP) is a powerful molecular marker technique that has been widely used in population genetics and molecular mapping studies for various organisms. However, the technique has not been used for studying Puccinia striiformis f. sp. tritici (Pst), the wheat stripe rust pathogen. In this study, we developed over a hundred secreted protein gene-derived SNP (SP-SNP) markers and used 92 markers to study the population structure of Pst. From 352 isolates collected in the United States, we identified 242 multi-locus genotypes. The SP-SNP genotypes had a moderate, but significant correlation with the virulence phenotype data. Clustering of the multi-locus genotypes was consistent by various analyses, revealing distinct genetic groups. Analysis of molecular variance detected significant differences between the eastern and western US Pst populations. High heterozygosity was found in the US population with significant differences identified among epidemiological regions. Analysis of population differentiation revealed that populations between the eastern and western US were highly differentiated while moderate differentiation was found in populations within the western or eastern US. Isolates from the western US were more diverse than isolates from the eastern US. The information is useful for guiding the disease management in different epidemiological regions.
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Petre B, Saunders DGO, Sklenar J, Lorrain C, Krasileva KV, Win J, Duplessis S, Kamoun S. Heterologous Expression Screens in Nicotiana benthamiana Identify a Candidate Effector of the Wheat Yellow Rust Pathogen that Associates with Processing Bodies. PLoS One 2016; 11:e0149035. [PMID: 26863009 PMCID: PMC4749346 DOI: 10.1371/journal.pone.0149035] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Accepted: 01/26/2016] [Indexed: 12/29/2022] Open
Abstract
Rust fungal pathogens of wheat (Triticum spp.) affect crop yields worldwide. The molecular mechanisms underlying the virulence of these pathogens remain elusive, due to the limited availability of suitable molecular genetic research tools. Notably, the inability to perform high-throughput analyses of candidate virulence proteins (also known as effectors) impairs progress. We previously established a pipeline for the fast-forward screens of rust fungal candidate effectors in the model plant Nicotiana benthamiana. This pipeline involves selecting candidate effectors in silico and performing cell biology and protein-protein interaction assays in planta to gain insight into the putative functions of candidate effectors. In this study, we used this pipeline to identify and characterize sixteen candidate effectors from the wheat yellow rust fungal pathogen Puccinia striiformis f sp tritici. Nine candidate effectors targeted a specific plant subcellular compartment or protein complex, providing valuable information on their putative functions in plant cells. One candidate effector, PST02549, accumulated in processing bodies (P-bodies), protein complexes involved in mRNA decapping, degradation, and storage. PST02549 also associates with the P-body-resident ENHANCER OF mRNA DECAPPING PROTEIN 4 (EDC4) from N. benthamiana and wheat. We propose that P-bodies are a novel plant cell compartment targeted by pathogen effectors.
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Affiliation(s)
- Benjamin Petre
- The Sainsbury Laboratory, Norwich Research Park, Norwich, United Kingdom
- INRA, UMR 1136 Interactions Arbres/Microorganismes, Centre INRA Nancy Lorraine, Champenoux, France
- Université de Lorraine, UMR 1136 Interactions Arbres/Microorganismes, Faculté des Sciences et Technologies, Vandoeuvre-lès-Nancy, France
| | - Diane G. O. Saunders
- The Sainsbury Laboratory, Norwich Research Park, Norwich, United Kingdom
- The Genome Analysis Centre, Norwich Research Park, Norwich, United Kingdom
- The John Innes Centre, Norwich Research Park, Norwich, United Kingdom
| | - Jan Sklenar
- The Sainsbury Laboratory, Norwich Research Park, Norwich, United Kingdom
| | - Cécile Lorrain
- The Sainsbury Laboratory, Norwich Research Park, Norwich, United Kingdom
- INRA, UMR 1136 Interactions Arbres/Microorganismes, Centre INRA Nancy Lorraine, Champenoux, France
- Université de Lorraine, UMR 1136 Interactions Arbres/Microorganismes, Faculté des Sciences et Technologies, Vandoeuvre-lès-Nancy, France
| | - Ksenia V. Krasileva
- The Sainsbury Laboratory, Norwich Research Park, Norwich, United Kingdom
- The Genome Analysis Centre, Norwich Research Park, Norwich, United Kingdom
| | - Joe Win
- The Sainsbury Laboratory, Norwich Research Park, Norwich, United Kingdom
| | - Sébastien Duplessis
- INRA, UMR 1136 Interactions Arbres/Microorganismes, Centre INRA Nancy Lorraine, Champenoux, France
- Université de Lorraine, UMR 1136 Interactions Arbres/Microorganismes, Faculté des Sciences et Technologies, Vandoeuvre-lès-Nancy, France
| | - Sophien Kamoun
- The Sainsbury Laboratory, Norwich Research Park, Norwich, United Kingdom
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Lorrain C, Hecker A, Duplessis S. Effector-Mining in the Poplar Rust Fungus Melampsora larici-populina Secretome. FRONTIERS IN PLANT SCIENCE 2015; 6:1051. [PMID: 26697026 PMCID: PMC4678189 DOI: 10.3389/fpls.2015.01051] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 11/11/2015] [Indexed: 05/24/2023]
Abstract
The poplar leaf rust fungus, Melampsora larici-populina has been established as a tree-microbe interaction model. Understanding the molecular mechanisms controlling infection by pathogens appears essential for durable management of tree plantations. In biotrophic plant-parasites, effectors are known to condition host cell colonization. Thus, investigation of candidate secreted effector proteins (CSEPs) is a major goal in the poplar-poplar rust interaction. Unlike oomycetes, fungal effectors do not share conserved motifs and candidate prediction relies on a set of a priori criteria established from reported bona fide effectors. Secretome prediction, genome-wide analysis of gene families and transcriptomics of M. larici-populina have led to catalogs of more than a thousand secreted proteins. Automatized effector-mining pipelines hold great promise for rapid and systematic identification and prioritization of CSEPs for functional characterization. In this review, we report on and discuss the current status of the poplar rust fungus secretome and prediction of candidate effectors from this species.
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Affiliation(s)
- Cécile Lorrain
- INRA, UMR 1136 Interactions Arbres/Microorganismes INRA/Université de Lorraine, Centre INRA Nancy Lorraine, Champenoux, France
- Université de Lorraine, UMR 1136 Interactions Arbres/Microorganismes Université de Lorraine/INRA, Faculté des Sciences et Technologies, Vandoeuvre-lès-Nancy, France
| | - Arnaud Hecker
- INRA, UMR 1136 Interactions Arbres/Microorganismes INRA/Université de Lorraine, Centre INRA Nancy Lorraine, Champenoux, France
- Université de Lorraine, UMR 1136 Interactions Arbres/Microorganismes Université de Lorraine/INRA, Faculté des Sciences et Technologies, Vandoeuvre-lès-Nancy, France
| | - Sébastien Duplessis
- INRA, UMR 1136 Interactions Arbres/Microorganismes INRA/Université de Lorraine, Centre INRA Nancy Lorraine, Champenoux, France
- Université de Lorraine, UMR 1136 Interactions Arbres/Microorganismes Université de Lorraine/INRA, Faculté des Sciences et Technologies, Vandoeuvre-lès-Nancy, France
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66
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Hirschburger D, Müller M, Voegele RT, Link T. Reference Genes in the Pathosystem Phakopsora pachyrhizi/ Soybean Suitable for Normalization in Transcript Profiling. Int J Mol Sci 2015; 16:23057-75. [PMID: 26404265 PMCID: PMC4613351 DOI: 10.3390/ijms160923057] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 09/14/2015] [Accepted: 09/18/2015] [Indexed: 11/16/2022] Open
Abstract
Phakopsora pachyrhizi is a devastating pathogen on soybean, endangering soybean production worldwide. Use of Host Induced Gene Silencing (HIGS) and the study of effector proteins could provide novel strategies for pathogen control. For both approaches quantification of transcript abundance by RT-qPCR is essential. Suitable stable reference genes for normalization are indispensable to obtain accurate RT-qPCR results. According to the Minimum Information for Publication of Quantitative Real-Time PCR Experiments (MIQE) guidelines and using algorithms geNorm and NormFinder we tested candidate reference genes from P. pachyrhizi and Glycine max for their suitability in normalization of transcript levels throughout the infection process. For P. pachyrhizi we recommend a combination of CytB and PDK or GAPDH for in planta experiments. Gene expression during in vitro stages and over the whole infection process was found to be highly unstable. Here, RPS14 and UbcE2 are ranked best by geNorm and NormFinder. Alternatively CytB that has the smallest Cq range (Cq: quantification cycle) could be used. We recommend specification of gene expression relative to the germ tube stage rather than to the resting urediospore stage. For studies omitting the resting spore and the appressorium stages a combination of Elf3 and RPS9, or PKD and GAPDH should be used. For normalization of soybean genes during rust infection Ukn2 and cons7 are recommended.
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Affiliation(s)
- Daniela Hirschburger
- Department of Phytopathology, Institute of Phytomedicine, Faculty of Agricultural Sciences, University of Hohenheim, Otto-Sander-Straße 5, 70599 Stuttgart, Germany.
| | - Manuel Müller
- Department of Phytopathology, Institute of Phytomedicine, Faculty of Agricultural Sciences, University of Hohenheim, Otto-Sander-Straße 5, 70599 Stuttgart, Germany.
| | - Ralf T Voegele
- Department of Phytopathology, Institute of Phytomedicine, Faculty of Agricultural Sciences, University of Hohenheim, Otto-Sander-Straße 5, 70599 Stuttgart, Germany.
| | - Tobias Link
- Department of Phytopathology, Institute of Phytomedicine, Faculty of Agricultural Sciences, University of Hohenheim, Otto-Sander-Straße 5, 70599 Stuttgart, Germany.
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Liu JJ, Sturrock RN, Sniezko RA, Williams H, Benton R, Zamany A. Transcriptome analysis of the white pine blister rust pathogen Cronartium ribicola: de novo assembly, expression profiling, and identification of candidate effectors. BMC Genomics 2015; 16:678. [PMID: 26338692 PMCID: PMC4559923 DOI: 10.1186/s12864-015-1861-1] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 08/18/2015] [Indexed: 12/21/2022] Open
Abstract
Background The fungus Cronartium ribicola (Cri) is an economically and ecologically important forest pathogen that causes white pine blister rust (WPBR) disease on five-needle pines. To cause stem cankers and kill white pine trees the fungus elaborates a life cycle with five stages of spore development on five-needle pines and the alternate host Ribes plants. To increase our understanding of molecular WP-BR interactions, here we report genome-wide transcriptional profile analysis of C. ribicola using RNA-seq. Results cDNA libraries were constructed from aeciospore, urediniospore, and western white pine (Pinus monticola) tissues post Cri infection. Over 200 million RNA-seq 100-bp paired-end (PE) reads from rust fungal spores were de novo assembled and a reference transcriptome was generated with 17,880 transcripts that were expressed from 13,629 unigenes. A total of 734 unique proteins were predicted as a part of the Cri secretome from complete open reading frames (ORFs), and 41 % of them were Cronartium-specific. This study further identified a repertoire of candidate effectors and other pathogenicity determinants. Differentially expressed genes (DEGs) were identified to gain an understanding of molecular events important during the WPBR fungus life cycle by comparing Cri transcriptomes at different infection stages. Large-scale changes of in planta gene expression profiles were observed, revealing that multiple fungal biosynthetic pathways were enhanced during mycelium growth inside infected pine stem tissues. Conversely, many fungal genes that were up-regulated at the urediniospore stage appeared to be signalling components and transporters. The secreted fungal protein genes that were up-regulated in pine needle tissues during early infection were primarily associated with cell wall modifications, possibly to mask the rust pathogen from plant defenses. Conclusion This comprehensive transcriptome profiling substantially improves our current understanding of molecular WP-BR interactions. The repertoire of candidate effectors and other putative pathogenicity determinants identified here are valuable for future functional analysis of Cri virulence and pathogenicity. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-1861-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jun-Jun Liu
- Pacific Forestry Centre, Canadian Forest Service, Natural Resources Canada, 506 West Burnside Road, Victoria, BC, V8Z 1M5, Canada.
| | - Rona N Sturrock
- Pacific Forestry Centre, Canadian Forest Service, Natural Resources Canada, 506 West Burnside Road, Victoria, BC, V8Z 1M5, Canada.
| | - Richard A Sniezko
- USDA Forest Service, Dorena Genetic Resource Center, 34963 Shoreview Road, Cottage Grove, OR, 97424, USA.
| | - Holly Williams
- Pacific Forestry Centre, Canadian Forest Service, Natural Resources Canada, 506 West Burnside Road, Victoria, BC, V8Z 1M5, Canada.
| | - Ross Benton
- Pacific Forestry Centre, Canadian Forest Service, Natural Resources Canada, 506 West Burnside Road, Victoria, BC, V8Z 1M5, Canada.
| | - Arezoo Zamany
- Pacific Forestry Centre, Canadian Forest Service, Natural Resources Canada, 506 West Burnside Road, Victoria, BC, V8Z 1M5, Canada.
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How eukaryotic filamentous pathogens evade plant recognition. Curr Opin Microbiol 2015; 26:92-101. [PMID: 26162502 DOI: 10.1016/j.mib.2015.06.012] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Revised: 06/16/2015] [Accepted: 06/17/2015] [Indexed: 12/29/2022]
Abstract
Plant pathogenic fungi and oomycetes employ sophisticated mechanisms for evading host recognition. After host penetration, many fungi and oomycetes establish a biotrophic interaction. It is assumed that different strategies employed by these pathogens to avoid triggering host defence responses, including establishment of biotrophic interfacial layers between the pathogen and host, masking of invading hyphae and active suppression of host defence mechanisms, are essential for a biotrophic parasitic lifestyle. During the infection process, filamentous plant pathogens secrete various effectors, which are hypothesized to be involved in facilitating effective host infection. Live-cell imaging of fungi and oomycetes secreting fluorescently labeled effector proteins as well as functional characterization of the components of biotrophic interfaces have led to the recent progress in understanding how eukaryotic filamentous pathogens evade plant recognition.
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69
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Petre B, Saunders DGO, Sklenar J, Lorrain C, Win J, Duplessis S, Kamoun S. Candidate Effector Proteins of the Rust Pathogen Melampsora larici-populina Target Diverse Plant Cell Compartments. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2015; 28:689-700. [PMID: 25650830 DOI: 10.1094/mpmi-01-15-0003-r] [Citation(s) in RCA: 111] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Rust fungi are devastating crop pathogens that deliver effector proteins into infected tissues to modulate plant functions and promote parasitic growth. The genome of the poplar leaf rust fungus Melampsora larici-populina revealed a large catalog of secreted proteins, some of which have been considered candidate effectors. Unraveling how these proteins function in host cells is a key to understanding pathogenicity mechanisms and developing resistant plants. In this study, we used an effectoromics pipeline to select, clone, and express 20 candidate effectors in Nicotiana benthamiana leaf cells to determine their subcellular localization and identify the plant proteins they interact with. Confocal microscopy revealed that six candidate effectors target the nucleus, nucleoli, chloroplasts, mitochondria, and discrete cellular bodies. We also used coimmunoprecipitation (coIP) and mass spectrometry to identify 606 N. benthamiana proteins that associate with the candidate effectors. Five candidate effectors specifically associated with a small set of plant proteins that may represent biologically relevant interactors. We confirmed the interaction between the candidate effector MLP124017 and TOPLESS-related protein 4 from poplar by in planta coIP. Altogether, our data enable us to validate effector proteins from M. larici-populina and reveal that these proteins may target multiple compartments and processes in plant cells. It also shows that N. benthamiana can be a powerful heterologous system to study effectors of obligate biotrophic pathogens.
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Affiliation(s)
- Benjamin Petre
- 1 The Sainsbury Laboratory, Norwich Research Park, NR4 7UH Norwich, U.K
- 2 INRA, UMR 1136 Interactions Arbres/Microorganismes, Centre INRA Nancy Lorraine, 54280 Champenoux, France
- 3 Université de Lorraine, UMR 1136 Interactions Arbres/Microorganismes, Faculté des Sciences et Technologies, 54506 Vandoeuvre-lès-Nancy, France
| | - Diane G O Saunders
- 1 The Sainsbury Laboratory, Norwich Research Park, NR4 7UH Norwich, U.K
- 4 The Genome Analysis Centre, Norwich Research Park, NR4 7UH Norwich, U.K
- 5 The John Innes Centre, Norwich Research Park, NR4 7UH Norwich, U.K
| | - Jan Sklenar
- 1 The Sainsbury Laboratory, Norwich Research Park, NR4 7UH Norwich, U.K
| | - Cécile Lorrain
- 1 The Sainsbury Laboratory, Norwich Research Park, NR4 7UH Norwich, U.K
- 2 INRA, UMR 1136 Interactions Arbres/Microorganismes, Centre INRA Nancy Lorraine, 54280 Champenoux, France
- 3 Université de Lorraine, UMR 1136 Interactions Arbres/Microorganismes, Faculté des Sciences et Technologies, 54506 Vandoeuvre-lès-Nancy, France
| | - Joe Win
- 1 The Sainsbury Laboratory, Norwich Research Park, NR4 7UH Norwich, U.K
| | - Sébastien Duplessis
- 2 INRA, UMR 1136 Interactions Arbres/Microorganismes, Centre INRA Nancy Lorraine, 54280 Champenoux, France
- 3 Université de Lorraine, UMR 1136 Interactions Arbres/Microorganismes, Faculté des Sciences et Technologies, 54506 Vandoeuvre-lès-Nancy, France
| | - Sophien Kamoun
- 1 The Sainsbury Laboratory, Norwich Research Park, NR4 7UH Norwich, U.K
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