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Wang J, Xu Y, Peng Y, Wang Y, Kang Z, Zhao J. A fully haplotype-resolved and nearly gap-free genome assembly of wheat stripe rust fungus. Sci Data 2024; 11:508. [PMID: 38755209 PMCID: PMC11099153 DOI: 10.1038/s41597-024-03361-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 05/10/2024] [Indexed: 05/18/2024] Open
Abstract
Stripe rust fungus Puccinia striiformis f. sp. tritici (Pst) is a destructive pathogen of wheat worldwide. Pst has a macrocyclic-heteroecious lifecycle, in which one-celled urediniospores are dikaryotic, each nucleus containing one haploid genome. We successfully generated the first fully haplotype-resolved and nearly gap-free chromosome-scale genome assembly of Pst by combining PacBio HiFi sequencing and trio-binning strategy. The genome size of the two haploid assemblies was 75.59 Mb and 75.91 Mb with contig N50 of 4.17 Mb and 4.60 Mb, and both had 18 pseudochromosomes. The high consensus quality values of 55.57 and 59.02 for both haplotypes confirmed the correctness of the assembly. Of the total 18 chromosomes, 15 and 16 were gapless while there were only five and two gaps for the remaining chromosomes of the two haplotypes, respectively. In total, 15,046 and 15,050 protein-coding genes were predicted for the two haplotypes, and the complete BUSCO scores achieved 97.7% and 97.9%, respectively. The genome will lay the foundation for further research on genetic variations and the evolution of rust fungi.
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Affiliation(s)
- Jierong Wang
- College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, 712100, China
- State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, Shaanxi, 712100, China
- College of Life Science, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Yiwen Xu
- College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Yuxi Peng
- College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Yiping Wang
- College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Zhensheng Kang
- College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, 712100, China.
- State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, Shaanxi, 712100, China.
| | - Jing Zhao
- College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, 712100, China.
- State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, Shaanxi, 712100, China.
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2
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Sperschneider J, Hewitt T, Lewis DC, Periyannan S, Milgate AW, Hickey LT, Mago R, Dodds PN, Figueroa M. Nuclear exchange generates population diversity in the wheat leaf rust pathogen Puccinia triticina. Nat Microbiol 2023; 8:2130-2141. [PMID: 37884814 PMCID: PMC10627818 DOI: 10.1038/s41564-023-01494-9] [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: 02/13/2023] [Accepted: 09/11/2023] [Indexed: 10/28/2023]
Abstract
In clonally reproducing dikaryotic rust fungi, non-sexual processes such as somatic nuclear exchange are postulated to play a role in diversity but have been difficult to detect due to the lack of genome resolution between the two haploid nuclei. We examined three nuclear-phased genome assemblies of Puccinia triticina, which causes wheat leaf rust disease. We found that the most recently emerged Australian lineage was derived by nuclear exchange between two pre-existing lineages, which originated in Europe and North America. Haplotype-specific phylogenetic analysis reveals that repeated somatic exchange events have shuffled haploid nuclei between long-term clonal lineages, leading to a global P. triticina population representing different combinations of a limited number of haploid genomes. Thus, nuclear exchange seems to be the predominant mechanism generating diversity and the emergence of new strains in this otherwise clonal pathogen. Such genomics-accelerated surveillance of pathogen evolution paves the way for more accurate global disease monitoring.
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Affiliation(s)
- Jana Sperschneider
- Black Mountain Science and Innovation Park, CSIRO Agriculture and Food, GPO, Canberra, Australian Capital Territory, Australia.
| | - Tim Hewitt
- Black Mountain Science and Innovation Park, CSIRO Agriculture and Food, GPO, Canberra, Australian Capital Territory, Australia
| | - David C Lewis
- Black Mountain Science and Innovation Park, CSIRO Agriculture and Food, GPO, Canberra, Australian Capital Territory, Australia
| | - Sambasivam Periyannan
- Black Mountain Science and Innovation Park, CSIRO Agriculture and Food, GPO, Canberra, Australian Capital Territory, Australia
- School of Agriculture and Environmental Science, Centre for Crop Health, The University of Southern Queensland, Toowoomba, Queensland, Australia
| | - Andrew W Milgate
- NSW Department of Primary Industries, Wagga Wagga Agricultural Institute, Wagga Wagga, New South Wales, Australia
| | - Lee T Hickey
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, Queensland, Australia
| | - Rohit Mago
- Black Mountain Science and Innovation Park, CSIRO Agriculture and Food, GPO, Canberra, Australian Capital Territory, Australia
| | - Peter N Dodds
- Black Mountain Science and Innovation Park, CSIRO Agriculture and Food, GPO, Canberra, Australian Capital Territory, Australia.
| | - Melania Figueroa
- Black Mountain Science and Innovation Park, CSIRO Agriculture and Food, GPO, Canberra, Australian Capital Territory, Australia.
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3
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Li C, Qiao L, Lu Y, Xing G, Wang X, Zhang G, Qian H, Shen Y, Zhang Y, Yao W, Cheng K, Ma Z, Liu N, Wang D, Zheng W. Gapless Genome Assembly of Puccinia triticina Provides Insights into Chromosome Evolution in Pucciniales. Microbiol Spectr 2023; 11:e0282822. [PMID: 36688678 PMCID: PMC9927501 DOI: 10.1128/spectrum.02828-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 12/02/2022] [Indexed: 01/24/2023] Open
Abstract
Chromosome evolution drives species evolution, speciation, and adaptive radiation. Accurate genome assembly is crucial to understanding chromosome evolution of species, such as dikaryotic fungi. Rust fungi (Pucciniales) in dikaryons represent the largest group of plant pathogens, but the evolutionary process of adaptive radiation in Pucciniales remains poorly understood. Here, we report a gapless genome for the wheat leaf rust fungus Puccinia triticina determined using PacBio high-fidelity (HiFi) sequencing. This gapless assembly contains two sets of chromosomes, showing that one contig represents one chromosome. Comparisons of homologous chromosomes between the phased haplotypes revealed that highly frequent small-scale sequence divergence shapes haplotypic variation. Genome analyses of Puccinia triticina along with other rusts revealed that recent transposable element bursts and extensive segmental gene duplications synergistically highlight the evolution of chromosome structures. Comparative analysis of chromosomes indicated that frequent chromosomal rearrangements may act as a major contributor to rapid radiation of Pucciniales. This study presents the first gapless, phased assembly for a dikaryotic rust fungus and provides insights into adaptive evolution and species radiation in Pucciniales. IMPORTANCE Rust fungi (Pucciniales) are the largest group of plant pathogens. Adaptive radiation is a predominant feature in Pucciniales evolution. Chromosome evolution plays an important role in adaptive evolution. Accurate chromosome-scale assembly is required to understand the role of chromosome evolution in Pucciniales. We took advantage of HiFi sequencing to construct a gapless, phased genome for Puccinia triticina. Further analyses revealed that the evolution of chromosome structures in rust lineage is shaped by the combination of transposable element bursts and segmental gene duplications. Chromosome comparisons of Puccinia triticina and other rusts suggested that frequent chromosomal arrangements may make remarkable contributions to high species diversity of rust fungi. Our results present the first gapless genome for Pucciniales and shed light on the feature of chromosome evolution in Pucciniales.
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Affiliation(s)
- Chuang Li
- State Key Laboratory of Wheat and Maize Crop Science, College of Life Sciences, Henan Agricultural University, Zhengzhou, China
- State Key Laboratory of Wheat and Maize Crop Science, College of Agronomy and Center for Crop Genome Engineering, Henan Agricultural University, Zhengzhou, China
| | - Liuhui Qiao
- State Key Laboratory of Wheat and Maize Crop Science, College of Life Sciences, Henan Agricultural University, Zhengzhou, China
- State Key Laboratory of Wheat and Maize Crop Science, College of Agronomy and Center for Crop Genome Engineering, Henan Agricultural University, Zhengzhou, China
| | - Yanan Lu
- State Key Laboratory of Wheat and Maize Crop Science, College of Life Sciences, Henan Agricultural University, Zhengzhou, China
| | - Guozhen Xing
- State Key Laboratory of Wheat and Maize Crop Science, College of Life Sciences, Henan Agricultural University, Zhengzhou, China
| | - Xiaodong Wang
- State Key Laboratory of North China Crop Improvement and Regulation, College of Plant Protection, Hebei Agricultural University, Baoding, China
| | | | - Huimin Qian
- State Key Laboratory of Wheat and Maize Crop Science, College of Life Sciences, Henan Agricultural University, Zhengzhou, China
| | - Yilin Shen
- State Key Laboratory of Wheat and Maize Crop Science, College of Life Sciences, Henan Agricultural University, Zhengzhou, China
| | - Yibo Zhang
- State Key Laboratory of Wheat and Maize Crop Science, College of Life Sciences, Henan Agricultural University, Zhengzhou, China
| | - Wen Yao
- State Key Laboratory of Wheat and Maize Crop Science, College of Life Sciences, Henan Agricultural University, Zhengzhou, China
| | - Kun Cheng
- State Key Laboratory of Wheat and Maize Crop Science, College of Life Sciences, Henan Agricultural University, Zhengzhou, China
| | - Zhenling Ma
- State Key Laboratory of Wheat and Maize Crop Science, College of Life Sciences, Henan Agricultural University, Zhengzhou, China
| | - Na Liu
- State Key Laboratory of Wheat and Maize Crop Science, College of Life Sciences, Henan Agricultural University, Zhengzhou, China
| | - Daowen Wang
- State Key Laboratory of Wheat and Maize Crop Science, College of Agronomy and Center for Crop Genome Engineering, Henan Agricultural University, Zhengzhou, China
| | - Wenming Zheng
- State Key Laboratory of Wheat and Maize Crop Science, College of Life Sciences, Henan Agricultural University, Zhengzhou, China
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Hoang MTV, Irinyi L, Hu Y, Schwessinger B, Meyer W. Long-Reads-Based Metagenomics in Clinical Diagnosis With a Special Focus on Fungal Infections. Front Microbiol 2022; 12:708550. [PMID: 35069461 PMCID: PMC8770865 DOI: 10.3389/fmicb.2021.708550] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 12/03/2021] [Indexed: 12/12/2022] Open
Abstract
Identification of the causative infectious agent is essential in the management of infectious diseases, with the ideal diagnostic method being rapid, accurate, and informative, while remaining cost-effective. Traditional diagnostic techniques rely on culturing and cell propagation to isolate and identify the causative pathogen. These techniques are limited by the ability and the time required to grow or propagate an agent in vitro and the facts that identification based on morphological traits are non-specific, insensitive, and reliant on technical expertise. The evolution of next-generation sequencing has revolutionized genomic studies to generate more data at a cheaper cost. These are divided into short- and long-read sequencing technologies, depending on the length of reads generated during sequencing runs. Long-read sequencing also called third-generation sequencing emerged commercially through the instruments released by Pacific Biosciences and Oxford Nanopore Technologies, although relying on different sequencing chemistries, with the first one being more accurate both platforms can generate ultra-long sequence reads. Long-read sequencing is capable of entirely spanning previously established genomic identification regions or potentially small whole genomes, drastically improving the accuracy of the identification of pathogens directly from clinical samples. Long-read sequencing may also provide additional important clinical information, such as antimicrobial resistance profiles and epidemiological data from a single sequencing run. While initial applications of long-read sequencing in clinical diagnosis showed that it could be a promising diagnostic technique, it also has highlighted the need for further optimization. In this review, we show the potential long-read sequencing has in clinical diagnosis of fungal infections and discuss the pros and cons of its implementation.
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Affiliation(s)
- Minh Thuy Vi Hoang
- Molecular Mycology Research Laboratory, Centre for Infectious Diseases and Microbiology, Faculty of Medicine and Health, Sydney Medical School, Westmead Clinical School, The University of Sydney, Sydney, NSW, Australia
- Westmead Institute for Medical Research, Westmead, NSW, Australia
| | - Laszlo Irinyi
- Molecular Mycology Research Laboratory, Centre for Infectious Diseases and Microbiology, Faculty of Medicine and Health, Sydney Medical School, Westmead Clinical School, The University of Sydney, Sydney, NSW, Australia
- Westmead Institute for Medical Research, Westmead, NSW, Australia
- Sydney Infectious Disease Institute, The University of Sydney, Sydney, NSW, Australia
| | - Yiheng Hu
- Research School of Biology, Australia National University, Canberra, ACT, Australia
| | | | - Wieland Meyer
- Molecular Mycology Research Laboratory, Centre for Infectious Diseases and Microbiology, Faculty of Medicine and Health, Sydney Medical School, Westmead Clinical School, The University of Sydney, Sydney, NSW, Australia
- Westmead Institute for Medical Research, Westmead, NSW, Australia
- Sydney Infectious Disease Institute, The University of Sydney, Sydney, NSW, Australia
- Westmead Hospital (Research and Education Network), Westmead, NSW, Australia
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5
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Baldrich P, Chaya T, Caplan JL, Meyers BC. Genome Assembly and Transcriptome of Colletotrichum sublineola CsGL1, a New Resource to Study Anthracnose Disease in Sorghum. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2021; 34:1209-1211. [PMID: 34662144 DOI: 10.1094/mpmi-04-21-0094-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Colletotrichum species are globally distributed and well known as members of a destructive phytopathogenic genus, causing the anthracnose disease in a wide variety of crops and fruits. Colletotrichum sublineola is the causal agent of the anthracnose disease in sorghum, causing losses of up to 50% in yield. Here, we used PacBio sequencing combined with RNA-seq to generate a chromosome-level assembly and annotation of the Colletotrichum sublineola strain CsGL1.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
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Affiliation(s)
| | - Timothy Chaya
- Department Plant and Soil Sciences, University of Delaware, Newark, DE 19716, U.S.A
| | - Jeffrey L Caplan
- Department Plant and Soil Sciences, University of Delaware, Newark, DE 19716, U.S.A
| | - Blake C Meyers
- Donald Danforth Plant Science Center, St. Louis, MO 63132, U.S.A
- University of Missouri-Columbia, Division of Plant Sciences, 52 Agriculture Lab, Columbia, MO 65211, U.S.A
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6
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Wu JQ, Song L, Ding Y, Dong C, Hasan M, Park RF. A Chromosome-Scale Assembly of the Wheat Leaf Rust Pathogen Puccinia triticina Provides Insights Into Structural Variations and Genetic Relationships With Haplotype Resolution. Front Microbiol 2021; 12:704253. [PMID: 34394053 PMCID: PMC8358450 DOI: 10.3389/fmicb.2021.704253] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Accepted: 07/12/2021] [Indexed: 11/24/2022] Open
Abstract
Despite the global economic importance of the wheat leaf rust pathogen Puccinia triticina (Pt), genomic resources for Pt are limited and chromosome-level assemblies of Pt are lacking. Here, we present a complete haplotype-resolved genome assembly at a chromosome-scale for Pt using the Australian pathotype 64-(6),(7),(10),11 (Pt64; North American race LBBQB) built upon the newly developed technologies of PacBio and Hi-C sequencing. PacBio reads with ∼200-fold coverage (29.8 Gb data) were assembled by Falcon and Falcon-unzip and subsequently scaffolded with Hi-C data using Falcon-phase and Proximo. This approach allowed us to construct 18 chromosome pseudomolecules ranging from 3.5 to 12.3 Mb in size for each haplotype of the dikaryotic genome of Pt64. Each haplotype had a total length of ∼147 Mb, scaffold N50 of ∼9.4 Mb, and was ∼93% complete for BUSCOs. Each haplotype had ∼29,800 predicted genes, of which ∼2,000 were predicted as secreted proteins (SPs). The investigation of structural variants (SVs) between haplotypes A and B revealed that 10% of the total genome was spanned by SVs, highlighting variations previously undetected by short-read based assemblies. For the first time, the mating type (MAT) genes on each haplotype of Pt64 were identified, which showed that MAT loci a and b are located on two chromosomes (chromosomes 7 and 14), representing a tetrapolar type. Furthermore, the Pt64 assembly enabled haplotype-based evolutionary analyses for 21 Australian Pt isolates, which highlighted the importance of a haplotype resolved reference when inferring genetic relationships using whole genome SNPs. This Pt64 assembly at chromosome-scale with full phase information provides an invaluable resource for genomic and evolutionary research, which will accelerate the understanding of molecular mechanisms underlying Pt-wheat interactions and facilitate the development of durable resistance to leaf rust in wheat and sustainable control of rust disease.
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Affiliation(s)
- Jing Qin Wu
- Plant Breeding Institute, School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Sydney, NSW, Australia
| | - Long Song
- Plant Breeding Institute, School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Sydney, NSW, Australia
| | - Yi Ding
- Plant Breeding Institute, School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Sydney, NSW, Australia
| | - Chongmei Dong
- Plant Breeding Institute, School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Sydney, NSW, Australia
| | - Mafruha Hasan
- Plant Breeding Institute, School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Sydney, NSW, Australia
| | - Robert F Park
- Plant Breeding Institute, School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Sydney, NSW, Australia
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7
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Xie Y, Zhong Y, Chang J, Kwan HS. Chromosome-level de novo assembly of Coprinopsis cinerea A43mut B43mut pab1-1 #326 and genetic variant identification of mutants using Nanopore MinION sequencing. Fungal Genet Biol 2020; 146:103485. [PMID: 33253902 DOI: 10.1016/j.fgb.2020.103485] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 10/22/2020] [Accepted: 11/13/2020] [Indexed: 11/26/2022]
Abstract
The homokaryotic Coprinopsis cinerea strain A43mut B43mut pab1-1 #326 is a widely used experimental model for developmental studies in mushroom-forming fungi. It can grow on defined artificial media and complete the whole lifecycle within two weeks. The mutations in mating type factors A and B result in the special feature of clamp formation and fruiting without mating. This feature allows investigations and manipulations with a homokaryotic genetic background. Current genome assembly of strain #326 was based on short-read sequencing data and was highly fragmented, leading to the bias in gene annotation and downstream analyses. Here, we report a chromosome-level genome assembly of strain #326. Oxford Nanopore Technology (ONT) MinION sequencing was used to get long reads. Illumina short reads was used to polish the sequences. A combined assembly yield 13 chromosomes and a mitochondrial genome as individual scaffolds. The assembly has 15,250 annotated genes with a high synteny with the C. cinerea strain Okayama-7 #130. This assembly has great improvement on contiguity and annotations. It is a suitable reference for further genomic studies, especially for the genetic, genomic and transcriptomic analyses in ONT long reads. Single nucleotide variants and structural variants in six mutagenized and cisplatin-screened mutants could be identified and validated. A 66 bp deletion in Ras GTPase-activating protein (RasGAP) was found in all mutants. To make a better use of ONT sequencing platform, we modified a high-molecular-weight genomic DNA isolation protocol based on magnetic beads for filamentous fungi. This study showed the use of MinION to construct a fungal reference genome and to perform downstream studies in an individual laboratory. An experimental workflow was proposed, from DNA isolation and whole genome sequencing, to genome assembly and variant calling. Our results provided solutions and parameters for fungal genomic analysis on MinION sequencing platform.
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Affiliation(s)
- Yichun Xie
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong Special Administrative Region
| | - Yiyi Zhong
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong Special Administrative Region
| | - Jinhui Chang
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong Special Administrative Region; The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen, China
| | - Hoi Shan Kwan
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong Special Administrative Region.
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8
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Vasquez-Gross H, Kaur S, Epstein L, Dubcovsky J. A haplotype-phased genome of wheat stripe rust pathogen Puccinia striiformis f. sp. tritici, race PST-130 from the Western USA. PLoS One 2020; 15:e0238611. [PMID: 33175843 PMCID: PMC7657539 DOI: 10.1371/journal.pone.0238611] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 10/28/2020] [Indexed: 01/27/2023] Open
Abstract
More virulent and aggressive races of Puccinia striiformis f. sp. tritici (Pst), the pathogen causing wheat stripe rust, have been spreading around the world since 2000 causing large grain yield losses. A better understanding of the genome and genetic diversity of these new Pst races will be useful to develop new strategies to ameliorate these losses. In this study, we generated an improved genome assembly of a post-2000 virulent race from the Western USA designated as PST-130. We implemented a haplotype phasing strategy using the diploid-aware assembler, Falcon-Unzip and new long-read technology from PacBio to phase the two genomes of this dikaryotic organism. The combination of these new technologies resulted in an improved PST-130 assembly with only 151 contigs (85.4 Mb, N50 of 1.44 Mb), and a complementary assembly (haplotigs) with 458 contigs (65.9 Mb, N50 of 0.235 Mb, PRJNA650506). This new assembly improved gene predictions resulting in 228 more predicted complete genes than in the initial Illumina assembly (29,178 contigs, N50 of 5 kb). The alignment of the non-repetitive primary and haplotig contigs revealed and average of 5.22 SNP/kb, with 39.1% showing <2 SNP/kb and 15.9% >10 SNP/kb. This large divergent regions may represent introgressions of chromosome segments from more divergent Pst races in regions where a complete sexual cycle and recombination are possible. We hypothesize that some of the divergent regions in PST-130 may be related to the European "Warrior" race PST-DK0911 because this genome is more similar to PST-130 (3.18 SNP/kb) than to the older European race PST-104E (3.75 SNP/kb). Complete phasing of additional Pst genomes or sequencing individual nuclei will facilitate the tracing of the haploid genomes introduced by the new Pst races into local populations.
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Affiliation(s)
- Hans Vasquez-Gross
- Department of Plant Sciences, University of California, Davis, CA, United States of America
| | - Sukhwinder Kaur
- Department of Plant Pathology, University of California, Davis, CA, United States of America
| | - Lynn Epstein
- Department of Plant Pathology, University of California, Davis, CA, United States of America
| | - Jorge Dubcovsky
- Department of Plant Sciences, University of California, Davis, CA, United States of America
- Howard Hughes Medical Institute, Chevy Chase, MD, United States of America
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9
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Integrated Analysis of Gene Expression, SNP, InDel, and CNV Identifies Candidate Avirulence Genes in Australian Isolates of the Wheat Leaf Rust Pathogen Puccinia triticina. Genes (Basel) 2020; 11:genes11091107. [PMID: 32967372 PMCID: PMC7564353 DOI: 10.3390/genes11091107] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 09/18/2020] [Indexed: 11/17/2022] Open
Abstract
The leaf rust pathogen, Puccinia triticina (Pt), threatens global wheat production. The deployment of leaf rust (Lr) resistance (R) genes in wheat varieties is often followed by the development of matching virulence in Pt due to presumed changes in avirulence (Avr) genes in Pt. Identifying such Avr genes is a crucial step to understand the mechanisms of wheat-rust interactions. This study is the first to develop and apply an integrated framework of gene expression, single nucleotide polymorphism (SNP), insertion/deletion (InDel), and copy number variation (CNV) analysis in a rust fungus and identify candidate avirulence genes. Using a long-read based de novo genome assembly of an isolate of Pt ('Pt104') as the reference, whole-genome resequencing data of 12 Pt pathotypes derived from three lineages Pt104, Pt53, and Pt76 were analyzed. Candidate avirulence genes were identified by correlating virulence profiles with small variants (SNP and InDel) and CNV, and RNA-seq data of an additional three Pt isolates to validate expression of genes encoding secreted proteins (SPs). Out of the annotated 29,043 genes, 2392 genes were selected as SP genes with detectable expression levels. Small variant comparisons between the isolates identified 27-40 candidates and CNV analysis identified 14-31 candidates for each Avr gene, which when combined, yielded the final 40, 64, and 69 candidates for AvrLr1, AvrLr15, and AvrLr24, respectively. Taken together, our results will facilitate future work on experimental validation and cloning of Avr genes. In addition, the integrated framework of data analysis that we have developed and reported provides a more comprehensive approach for Avr gene mining than is currently available.
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10
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Peng J, Rojas JA, Sang H, Proffer TJ, Outwater CA, Vilgalys R, Sundin GW. Draft Genome Sequence Resource for Blumeriella jaapii, the Cherry Leaf Spot Pathogen. PHYTOPATHOLOGY 2020; 110:1507-1510. [PMID: 32338196 DOI: 10.1094/phyto-03-20-0082-a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Blumeriella jaapii is the causal agent of cherry leaf spot (CLS), the most important disease of tart cherry in the Midwestern United States. Infection of leaves by B. jaapii leads to premature defoliation, which places trees at heightened risk of winter injury and death. Current management of CLS relies primarily on the application of three important fungicide classes, quinone outside inhibitors, sterol demethylation inhibitors, and succinate dehydrogenase inhibitors. Here, we present the first high-quality genome of B. jaapii through a hybrid assembly of PacBio long reads and Illumina short reads. The assembled draft genome of B. jaapii is 47.4 Mb and consists of 95 contigs with a N50 value of 1.5 Mb. The genomic information of B. jaapii, representing the most complete sequenced genome of the family Dermateaceae (Ascomycota) to date, provides a valuable resource for identifying fungicide resistance mechanisms of this pathogen and expands our knowledge of the phytopathogenic fungi in this family.
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Affiliation(s)
- Jingyu Peng
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, MI, U.S.A
| | - J Alejandro Rojas
- Department of Biology, Duke University, Durham, NC, U.S.A
- Department of Entomology and Plant Pathology, University of Arkansas, Fayetteville, AR, U.S.A
| | - Hyunkyu Sang
- Department of Biotechnology, Chonnam National University, Gwangju, South Korea
| | - Tyre J Proffer
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, MI, U.S.A
| | - Cory A Outwater
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, MI, U.S.A
| | - Rytas Vilgalys
- Department of Biology, Duke University, Durham, NC, U.S.A
| | - George W Sundin
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, MI, U.S.A
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11
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Wu JQ, Dong C, Song L, Park RF. Long-Read-Based de novo Genome Assembly and Comparative Genomics of the Wheat Leaf Rust Pathogen Puccinia triticina Identifies Candidates for Three Avirulence Genes. Front Genet 2020; 11:521. [PMID: 32582280 PMCID: PMC7287177 DOI: 10.3389/fgene.2020.00521] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 04/29/2020] [Indexed: 11/18/2022] Open
Abstract
Leaf rust, caused by Puccinia triticina (Pt), is one of the most devastating diseases of wheat, affecting production in nearly all wheat-growing regions worldwide. Despite its economic importance, genomic resources for Pt are very limited. In the present study, we have used long-read sequencing (LRS) and the pipeline of FALCON and FALCON-Unzip (v4.1.0) to carry out the first LRS-based de novo genome assembly for Pt. Using 22.4-Gb data with an average read length of 11.6 kb and average coverage of 150-fold, we generated a genome assembly for Pt104 [strain 104-2,3,(6),(7),11; isolate S423], considered to be the founding isolate of a clonal lineage of Pt in Australia. The Pt104 genome contains 162 contigs with a total length of 140.5 Mb and N50 of 2 Mb, with the associated haplotigs providing haplotype information for 91% of the genome. This represents the best quality of Pt genome assembly to date, which reduces the contig number by 91-fold and improves the N50 by 4-fold as compared to the previous Pt race1 assembly. An annotation pipeline that combined multiple lines of evidence including the transcriptome assemblies derived from RNA-Seq, previously identified expressed sequence tags and Pt race 1 protein sequences predicted 29,043 genes for Pt104 genome. Based on the presence of a signal peptide, no transmembrane segment, and no target location to mitochondria, 2,178 genes were identified as secreted proteins (SPs). Whole-genome sequencing (Illumina paired-end) was performed for Pt104 and six additional strains with differential virulence profile on the wheat leaf rust resistance genes Lr26, Lr2a, and Lr3ka. To identify candidates for the corresponding avirulence genes AvrLr26, AvrLr2a, and AvrLr3ka, genetic variation within each strain was first identified by mapping to the Pt104 genome. Variants within predicted SP genes between the strains were then correlated to the virulence profiles, identifying 38, 31, and 37 candidates for AvrLr26, AvrLr2a, and AvrLr3ka, respectively. The identification of these candidate genes lays a good foundation for future studies on isolating these avirulence genes, investigating the molecular mechanisms underlying host-pathogen interactions, and the development of new diagnostic tools for pathogen monitoring.
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Affiliation(s)
| | | | | | - Robert F. Park
- Plant Breeding Institute, School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Sydney, NSW, Australia
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12
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Schwessinger B, Chen YJ, Tien R, Vogt JK, Sperschneider J, Nagar R, McMullan M, Sicheritz-Ponten T, Sørensen CK, Hovmøller MS, Rathjen JP, Justesen AF. Distinct Life Histories Impact Dikaryotic Genome Evolution in the Rust Fungus Puccinia striiformis Causing Stripe Rust in Wheat. Genome Biol Evol 2020; 12:597-617. [PMID: 32271913 DOI: 10.1101/859728] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/03/2020] [Indexed: 05/27/2023] Open
Abstract
Stripe rust of wheat, caused by the obligate biotrophic fungus Puccinia striiformis f.sp. tritici, is a major threat to wheat production worldwide with an estimated yearly loss of US $1 billion. The recent advances in long-read sequencing technologies and tailored-assembly algorithms enabled us to disentangle the two haploid genomes of Pst. This provides us with haplotype-specific information at a whole-genome level. Exploiting this novel information, we perform whole-genome comparative genomics of two P. striiformis f.sp. tritici isolates with contrasting life histories. We compare one isolate of the old European lineage (PstS0), which has been asexual for over 50 years, and a Warrior isolate (PstS7 lineage) from a novel incursion into Europe in 2011 from a sexual population in the Himalayan region. This comparison provides evidence that long-term asexual evolution leads to genome expansion, accumulation of transposable elements, and increased heterozygosity at the single nucleotide, structural, and allele levels. At the whole-genome level, candidate effectors are not compartmentalized and do not exhibit reduced levels of synteny. Yet we were able to identify two subsets of candidate effector populations. About 70% of candidate effectors are invariant between the two isolates, whereas 30% are hypervariable. The latter might be involved in host adaptation on wheat and explain the different phenotypes of the two isolates. Overall, this detailed comparative analysis of two haplotype-aware assemblies of P. striiformis f.sp. tritici is the first step in understanding the evolution of dikaryotic rust fungi at a whole-genome level.
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Affiliation(s)
- Benjamin Schwessinger
- Research School of Biology, The Australian National University, Acton, Canberra, Australian Capital Territory, Australia
| | - Yan-Jun Chen
- The GLOBE Institute, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Richard Tien
- School of Dentistry, The University of Western Australia, Nedlands, Western Australia, Australia
| | - Josef Korbinian Vogt
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Denmark
| | - Jana Sperschneider
- Biological Data Science Institute, The Australian National University, Acton, Canberra, Australian Capital Territory, Australia
| | - Ramawatar Nagar
- Research School of Biology, The Australian National University, Acton, Canberra, Australian Capital Territory, Australia
| | - Mark McMullan
- Earlham Institute, Norwich Research Park, United Kingdom
| | - Thomas Sicheritz-Ponten
- The GLOBE Institute, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Chris K Sørensen
- Department of Agroecology, Faculty of Science and Technology, Aarhus University, Slagelse, Denmark
| | | | - John P Rathjen
- Research School of Biology, The Australian National University, Acton, Canberra, Australian Capital Territory, Australia
| | - Annemarie Fejer Justesen
- Department of Agroecology, Faculty of Science and Technology, Aarhus University, Slagelse, Denmark
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13
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Schwessinger B, Chen YJ, Tien R, Vogt JK, Sperschneider J, Nagar R, McMullan M, Sicheritz-Ponten T, Sørensen CK, Hovmøller MS, Rathjen JP, Justesen AF. Distinct Life Histories Impact Dikaryotic Genome Evolution in the Rust Fungus Puccinia striiformis Causing Stripe Rust in Wheat. Genome Biol Evol 2020; 12:597-617. [PMID: 32271913 PMCID: PMC7250506 DOI: 10.1093/gbe/evaa071] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/03/2020] [Indexed: 12/12/2022] Open
Abstract
Stripe rust of wheat, caused by the obligate biotrophic fungus Puccinia striiformis f.sp. tritici, is a major threat to wheat production worldwide with an estimated yearly loss of US $1 billion. The recent advances in long-read sequencing technologies and tailored-assembly algorithms enabled us to disentangle the two haploid genomes of Pst. This provides us with haplotype-specific information at a whole-genome level. Exploiting this novel information, we perform whole-genome comparative genomics of two P. striiformis f.sp. tritici isolates with contrasting life histories. We compare one isolate of the old European lineage (PstS0), which has been asexual for over 50 years, and a Warrior isolate (PstS7 lineage) from a novel incursion into Europe in 2011 from a sexual population in the Himalayan region. This comparison provides evidence that long-term asexual evolution leads to genome expansion, accumulation of transposable elements, and increased heterozygosity at the single nucleotide, structural, and allele levels. At the whole-genome level, candidate effectors are not compartmentalized and do not exhibit reduced levels of synteny. Yet we were able to identify two subsets of candidate effector populations. About 70% of candidate effectors are invariant between the two isolates, whereas 30% are hypervariable. The latter might be involved in host adaptation on wheat and explain the different phenotypes of the two isolates. Overall, this detailed comparative analysis of two haplotype-aware assemblies of P. striiformis f.sp. tritici is the first step in understanding the evolution of dikaryotic rust fungi at a whole-genome level.
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Affiliation(s)
- Benjamin Schwessinger
- Research School of Biology, The Australian National University, Acton, Canberra, Australian Capital Territory, Australia
| | - Yan-Jun Chen
- The GLOBE Institute, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Richard Tien
- School of Dentistry, The University of Western Australia, Nedlands, Western Australia, Australia
| | - Josef Korbinian Vogt
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Denmark
| | - Jana Sperschneider
- Biological Data Science Institute, The Australian National University, Acton, Canberra, Australian Capital Territory, Australia
| | - Ramawatar Nagar
- Research School of Biology, The Australian National University, Acton, Canberra, Australian Capital Territory, Australia
| | - Mark McMullan
- Earlham Institute, Norwich Research Park, United Kingdom
| | - Thomas Sicheritz-Ponten
- The GLOBE Institute, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Chris K Sørensen
- Department of Agroecology, Faculty of Science and Technology, Aarhus University, Slagelse, Denmark
| | | | - John P Rathjen
- Research School of Biology, The Australian National University, Acton, Canberra, Australian Capital Territory, Australia
| | - Annemarie Fejer Justesen
- Department of Agroecology, Faculty of Science and Technology, Aarhus University, Slagelse, Denmark
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14
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Suzuki O, Koura M, Uchio-Yamada K, Sasaki M. Analysis of the transgene insertion pattern in a transgenic mouse strain using long-read sequencing. Exp Anim 2020; 69:279-286. [PMID: 32051389 PMCID: PMC7445054 DOI: 10.1538/expanim.19-0118] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Transgene insertion patterns are critical for the analysis of transgenic animals because
the influence of transgenes may change depending on the insertion pattern (such as copy
numbers and orientations of concatenations) and the insertion position in the genome. We
previously reported a genomic walking strategy to locate transgenes in the genomes of
transgenic mice (Exp. Anim. 53: 103–111, 2004) and to analyze transgene insertion patterns
(Exp. Anim. 55: 65–69, 2006). With such strategies, however, we could not determine the
copy number of transgenes or global genome modification induced by transgene insertion due
to read-length limitation. In this study, we used a long-read sequencer (MinION, Oxford
Nanopore Technologies) to overcome this limitation. We obtained 922,210 reads using MinION
with genomic DNA from a transgenic mouse strain (4C30, Proc. Jpn. Acad. Ser. B. Phys.
Biol. Sci. 87: 550–562, 2011). Among the reads, we found one 21,457-bp read containing the
transgene using a local BLAST search. Nucleotide dot plot analysis revealed that the
transgene was inserted in the genome as a tandem concatemer with an almost entire
construct (15–3,508 of 3,508 bp) and a partial fragment (4–660, 657 bp). Ensembl’s BLAST
search against the C57BL/6N genome revealed a 9,388-bp deletion at the insertion position
in the intron of the Sgcd gene, confirming that mutations such as a large
genomic deletion could occur at the time of transgene insertion. Thus, long-read
sequencers are useful tools for the analysis of transgene insertion patterns.
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Affiliation(s)
- Osamu Suzuki
- Laboratory of Animal Models for Human Diseases, National Institutes of Biomedical Innovation, Health and Nutrition,7-6-8 Saito-Asagi, Ibaraki, Ibaraki, Osaka 568-0085, Japan
| | - Minako Koura
- Laboratory of Animal Models for Human Diseases, National Institutes of Biomedical Innovation, Health and Nutrition,7-6-8 Saito-Asagi, Ibaraki, Ibaraki, Osaka 568-0085, Japan
| | - Kozue Uchio-Yamada
- Laboratory of Animal Models for Human Diseases, National Institutes of Biomedical Innovation, Health and Nutrition,7-6-8 Saito-Asagi, Ibaraki, Ibaraki, Osaka 568-0085, Japan
| | - Mitsuho Sasaki
- Laboratory of Animal Models for Human Diseases, National Institutes of Biomedical Innovation, Health and Nutrition,7-6-8 Saito-Asagi, Ibaraki, Ibaraki, Osaka 568-0085, Japan
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15
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Schalamun M, Nagar R, Kainer D, Beavan E, Eccles D, Rathjen JP, Lanfear R, Schwessinger B. Harnessing the MinION: An example of how to establish long-read sequencing in a laboratory using challenging plant tissue from Eucalyptus pauciflora. Mol Ecol Resour 2019; 19:77-89. [PMID: 30118581 PMCID: PMC7380007 DOI: 10.1111/1755-0998.12938] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 08/08/2018] [Accepted: 08/10/2018] [Indexed: 11/28/2022]
Abstract
Long-read sequencing technologies are transforming our ability to assemble highly complex genomes. Realizing their full potential is critically reliant on extracting high-quality, high-molecular-weight (HMW) DNA from the organisms of interest. This is especially the case for the portable MinION sequencer which enables all laboratories to undertake their own genome sequencing projects, due to its low entry cost and minimal spatial footprint. One challenge of the MinION is that each group has to independently establish effective protocols for using the instrument, which can be time-consuming and costly. Here, we present a workflow and protocols that enabled us to establish MinION sequencing in our own laboratories, based on optimizing DNA extraction from a challenging plant tissue as a case study. Following the workflow illustrated, we were able to reliably and repeatedly obtain >6.5 Gb of long-read sequencing data with a mean read length of 13 kb and an N50 of 26 kb. Our protocols are open source and can be performed in any laboratory without special equipment. We also illustrate some more elaborate workflows which can increase mean and average read lengths if this is desired. We envision that our workflow for establishing MinION sequencing, including the illustration of potential pitfalls and suggestions of how to adapt it to other tissue types, will be useful to others who plan to establish long-read sequencing in their own laboratories.
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Affiliation(s)
- Miriam Schalamun
- Research School of BiologyThe Australian National UniversityActonACTAustralia
- Present address:
University of Natural Resources and Life SciencesViennaAustria
| | - Ramawatar Nagar
- Research School of BiologyThe Australian National UniversityActonACTAustralia
| | - David Kainer
- Research School of BiologyThe Australian National UniversityActonACTAustralia
| | - Eleanor Beavan
- Research School of BiologyThe Australian National UniversityActonACTAustralia
| | - David Eccles
- Malaghan Institute of Medical ResearchWellingtonNew Zealand
- Present address:
Malaghan Institute of Medical ResearchWellingtonNew Zealand
| | - John P. Rathjen
- Research School of BiologyThe Australian National UniversityActonACTAustralia
| | - Robert Lanfear
- Research School of BiologyThe Australian National UniversityActonACTAustralia
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16
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Schwessinger B, Sperschneider J, Cuddy WS, Garnica DP, Miller ME, Taylor JM, Dodds PN, Figueroa M, Park RF, Rathjen JP. A Near-Complete Haplotype-Phased Genome of the Dikaryotic Wheat Stripe Rust Fungus Puccinia striiformis f. sp. tritici Reveals High Interhaplotype Diversity. mBio 2018; 9:e02275-17. [PMID: 29463659 PMCID: PMC5821087 DOI: 10.1128/mbio.02275-17] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Accepted: 01/09/2018] [Indexed: 01/01/2023] Open
Abstract
A long-standing biological question is how evolution has shaped the genomic architecture of dikaryotic fungi. To answer this, high-quality genomic resources that enable haplotype comparisons are essential. Short-read genome assemblies for dikaryotic fungi are highly fragmented and lack haplotype-specific information due to the high heterozygosity and repeat content of these genomes. Here, we present a diploid-aware assembly of the wheat stripe rust fungus Puccinia striiformis f. sp. tritici based on long reads using the FALCON-Unzip assembler. Transcriptome sequencing data sets were used to infer high-quality gene models and identify virulence genes involved in plant infection referred to as effectors. This represents the most complete Puccinia striiformis f. sp. tritici genome assembly to date (83 Mb, 156 contigs, N50 of 1.5 Mb) and provides phased haplotype information for over 92% of the genome. Comparisons of the phase blocks revealed high interhaplotype diversity of over 6%. More than 25% of all genes lack a clear allelic counterpart. When we investigated genome features that potentially promote the rapid evolution of virulence, we found that candidate effector genes are spatially associated with conserved genes commonly found in basidiomycetes. Yet, candidate effectors that lack an allelic counterpart are more distant from conserved genes than allelic candidate effectors and are less likely to be evolutionarily conserved within the P. striiformis species complex and Pucciniales In summary, this haplotype-phased assembly enabled us to discover novel genome features of a dikaryotic plant-pathogenic fungus previously hidden in collapsed and fragmented genome assemblies.IMPORTANCE Current representations of eukaryotic microbial genomes are haploid, hiding the genomic diversity intrinsic to diploid and polyploid life forms. This hidden diversity contributes to the organism's evolutionary potential and ability to adapt to stress conditions. Yet, it is challenging to provide haplotype-specific information at a whole-genome level. Here, we take advantage of long-read DNA sequencing technology and a tailored-assembly algorithm to disentangle the two haploid genomes of a dikaryotic pathogenic wheat rust fungus. The two genomes display high levels of nucleotide and structural variations, which lead to allelic variation and the presence of genes lacking allelic counterparts. Nonallelic candidate effector genes, which likely encode important pathogenicity factors, display distinct genome localization patterns and are less likely to be evolutionary conserved than those which are present as allelic pairs. This genomic diversity may promote rapid host adaptation and/or be related to the age of the sequenced isolate since last meiosis.
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Affiliation(s)
- Benjamin Schwessinger
- Research School of Biology, the Australian National University, Acton, ACT, Australia
| | - Jana Sperschneider
- Centre for Environment and Life Sciences, CSIRO Agriculture and Food, Perth, WA, Australia
| | - William S Cuddy
- Plant Breeding Institute, Faculty of Agriculture and Environment, the University of Sydney, Narellan, NSW, Australia
- NSW Department of Primary Industries, Elizabeth Macarthur Agricultural Institute, Menangle, NSW, Australia
| | - Diana P Garnica
- Research School of Biology, the Australian National University, Acton, ACT, Australia
| | - Marisa E Miller
- Department of Plant Pathology, University of Minnesota, St. Paul, Minnesota, USA
| | - Jennifer M Taylor
- Black Mountain Laboratories, CSIRO Agriculture and Food, Canberra, ACT, Australia
| | - Peter N Dodds
- Black Mountain Laboratories, CSIRO Agriculture and Food, Canberra, ACT, Australia
| | - Melania Figueroa
- Department of Plant Pathology, University of Minnesota, St. Paul, Minnesota, USA
- Stakman-Borlaug Center for Sustainable Plant Health, University of Minnesota, St. Paul, Minnesota, USA
| | - Robert F Park
- Plant Breeding Institute, Faculty of Agriculture and Environment, the University of Sydney, Narellan, NSW, Australia
| | - John P Rathjen
- Research School of Biology, the Australian National University, Acton, ACT, Australia
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