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Lynn KMT, Wingfield MJ, Hammerbacher A, Barnes I. High-resolution melting curve analysis: A detection assay for Ceratocystis eucalypticola and C. manginecans in infected Eucalyptus. Fungal Biol 2024; 128:2062-2072. [PMID: 39174241 DOI: 10.1016/j.funbio.2024.07.011] [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: 03/25/2024] [Revised: 07/13/2024] [Accepted: 07/31/2024] [Indexed: 08/24/2024]
Abstract
Eucalyptus spp. in plantations are negatively affected by canker and wilt diseases caused by several species of Ceratocystis, particularly those in the Latin American Clade (LAC). Ceratocystis eucalypticola and Ceratocystis manginecans are of particular concern where disease epidemics are reported globally, with recent outbreaks emerging in South African and Indonesian Eucalyptus plantations. Consequently, a rapid screening protocol is required for these pathogens. In this study, a high-resolution melting curve analysis (HRMA) was developed to detect C. eucalypticola and C. manginecans that bypasses time-consuming isolation and post-PCR procedures. Primers targeting a 172 bp region of the cerato-platanin (CP) gene were designed. Using these primers, the accuracy of HRMA to detect and distinguish between these two LAC species was assessed using pure fungal DNA, and DNA extracted directly from Eucalyptus samples naturally infected with C. eucalypticola. The assay accurately detected the presence of C. eucalypticola and C. manginecans and quantifies their DNA, both from cultures, and directly from wood samples. HRMA further differentiated these two species from all other tested LAC individuals. This assay was also able to detect the presence of all the tested LAC species and distinguish seven of these, including C. fimbriata, to species level. Ceratocystis polyconidia was the only non-LAC off-target species detected. Based on these results, the developed assay can be used to rapidly identify C. eucalypticola and C. manginecans directly from infected plant material or fungal cultures, with the potential to also screen for several other LAC species.
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Affiliation(s)
- Kira M T Lynn
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Private Bag X20, Pretoria, 0028, South Africa
| | - Michael J Wingfield
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Private Bag X20, Pretoria, 0028, South Africa
| | - Almuth Hammerbacher
- Department of Zoology and Entomology, Forestry and Agricultural Biotechnology Institute (FABI), Faculty of Natural and Agricultural Sciences, University of Pretoria, Pretoria, South Africa
| | - Irene Barnes
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Private Bag X20, Pretoria, 0028, South Africa.
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Nufer MI, Coates BS, Abel CA, O'Neill P, McCracken M, Jain D, Pierce CA, Glover J, Towles T, Reddy GVP, Perera OP. Anatomy of a pest control failure: introgression of cytochrome P450 337B3 alleles from invasive old-world bollworm into native corn earworm (Lepidoptera: Noctuidae). JOURNAL OF INSECT SCIENCE (ONLINE) 2024; 24:28. [PMID: 39348592 PMCID: PMC11441577 DOI: 10.1093/jisesa/ieae094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 08/13/2024] [Accepted: 09/03/2024] [Indexed: 10/02/2024]
Abstract
The establishment of invasive species populations can threaten the ecological balance in naïve habitats and impact agricultural production practices. Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) (old-world bollworm, OWBW) and Helicoverpa zea (corn earworm, CEW) were geographically separated prior to the 2013 report of OWBW invasion into South America. Introgression of OWBW-specific cytochrome P450 337B3 (CYP337B3) gene into CEW was repeatedly detected across South America and the Caribbean. Two hybrids were documented from Texas in 2019. In this study, screening insects collected in Olathe, CO, USA, where a failure of pyrethroids to control CEW damage to conventional sweetcorn in 2023 detected 28.6% of insects with the OWBW-specific CYP337B3 marker. Nucleotide sequencing of the CYP337B3 gene identified 73.1% and 26.9% of insects carried CYP337B3v2 and CYP337B3v6 alleles, respectively, and 0.15 overall frequency of CYP337B3 alleles. Based on prior data for distinct phylogeographic origins of CYP337B3v2 and v6 alleles, our results indicate Olathe samples were derived from 2 different introductions: An uncertain source of the v6 allele that was initially reported in West Africa and possibly South American or Caribbean origin of the globally distributed v2 allele. One of the 1618 individuals screened also carried a ribosomal RNA internal transcribed spacer 1 derived from OWBW. Local selection pressures at the Olathe location imposed by repeated pyrethroid exposures are likely attributed to the prevalence of CYP337B3, where control practices hasten the accumulation of phenotypic resistance by adaptive introgression. Pyrethroid and other resistance factors carried by invasive OWBW may continue to impact CEW management tactics across the Americas.
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Affiliation(s)
- Marissa I Nufer
- Southern Insect Management Research Unit, USDA ARS, Stoneville, MS, USA
| | - Brad S Coates
- Corn Insects & Crop Genetics Research Unit, Science II, USDA-ARS, Ames, IA, USA
| | - Craig A Abel
- Corn Insects & Crop Genetics Research Unit, Science II, USDA-ARS, Ames, IA, USA
| | | | | | - Devendra Jain
- Southern Insect Management Research Unit, USDA ARS, Stoneville, MS, USA
- Department of Molecular Biology and Biotechnology, Maharana Pratap University for Agriculture and Technology, Udaipur, India
| | - Calvin A Pierce
- Southern Insect Management Research Unit, USDA ARS, Stoneville, MS, USA
| | - James Glover
- Southern Insect Management Research Unit, USDA ARS, Stoneville, MS, USA
| | - Tyler Towles
- Delta Research and Extension Center, Mississippi State University, Stoneville, MS, USA
| | - Gadi V P Reddy
- Southern Insect Management Research Unit, USDA ARS, Stoneville, MS, USA
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Wang JC, Chen HH, Hsu TW, Hung KH, Huang CC. A taxonomic revision of the genus Angelica (Apiaceae) in Taiwan with a new species A. aliensis. BOTANICAL STUDIES 2024; 65:3. [PMID: 38252347 PMCID: PMC10803708 DOI: 10.1186/s40529-023-00407-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Accepted: 12/13/2023] [Indexed: 01/23/2024]
Abstract
BACKGROUND Angelica L. sensu lato is a taxonomically complex genus, and many studies have utilized morphological and molecular features to resolve its classification issues. In Taiwan, there are six taxa within Angelica, and their taxonomic treatments have been a subject of controversy. In this study, we conducted a comprehensive analysis incorporating morphological and molecular (cpDNA and nrDNA) characteristics to revise the taxonomic treatments of Angelica in Taiwan. RESULTS As a result of our research, we have revised the classification between A. dahurica var. formosana and A. pubescens and merged two varieties of A. morrisonicola into a single taxon. A new taxon, A. aliensis, has been identified and found to share a close relationship with A. tarokoensis. Based on the morphological and molecular characteristics data, it has been determined that the former three taxa should be grouped into the Eurasian Angelica clade, while the remaining four taxa should belong to the littoral Angelica clade. Furthermore, Angelica species in Taiwan distributed at higher altitudes displayed higher genetic diversity, implying that the central mountain range of Taiwan serves as a significant reservoir of plant biodiversity. Genetic drift, such as bottlenecks, has been identified as a potential factor leading to the fixation or reduction of genetic diversity of populations in most Angelica species. We provide key to taxa, synopsis, phenology, and distribution for each taxon of Taiwan. CONCLUSIONS Our comprehensive analysis of morphological and molecular features has shed light on the taxonomic complexities within Angelica in Taiwan, resolving taxonomic issues and providing valuable insights into the phylogenetic relationships of Angelica in Taiwan.
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Affiliation(s)
- Jenn-Che Wang
- Department of Life Science, National Taiwan Normal University, Taipei, 106, Taiwan
| | - Hung-Hsin Chen
- Department of Life Science, National Taiwan Normal University, Taipei, 106, Taiwan
| | - Tsai-Wen Hsu
- Wild Plants Division, Taiwan Biodiversity Research Institute, Nantou, 552, Taiwan
| | - Kuo-Hsiang Hung
- Graduate Institute of Bioresources, Pingtung University of Science and Technology, Pingtung, 912, Taiwan.
- Forestry and Biodiversity Research Center, National Pingtung University of Science and Technology, Pingtung, 912, Taiwan.
| | - Chi-Chun Huang
- Wild Plants Division, Taiwan Biodiversity Research Institute, Nantou, 552, Taiwan.
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Kerr M, Leavitt SD. A Custom Regional DNA Barcode Reference Library for Lichen-Forming Fungi of the Intermountain West, USA, Increases Successful Specimen Identification. J Fungi (Basel) 2023; 9:741. [PMID: 37504730 PMCID: PMC10381598 DOI: 10.3390/jof9070741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 06/27/2023] [Accepted: 07/10/2023] [Indexed: 07/29/2023] Open
Abstract
DNA barcoding approaches provide powerful tools for characterizing fungal diversity. However, DNA barcoding is limited by poor representation of species-level diversity in fungal sequence databases. Can the development of custom, regionally focused DNA reference libraries improve species-level identification rates for lichen-forming fungi? To explore this question, we created a regional ITS database for lichen-forming fungi (LFF) in the Intermountain West of the United States. The custom database comprised over 4800 sequences and represented over 600 formally described and provisional species. Lichen communities were sampled at 11 sites throughout the Intermountain West, and LFF diversity was characterized using high-throughput ITS2 amplicon sequencing. We compared the species-level identification success rates from our bulk community samples using our regional ITS database and the widely used UNITE database. The custom regional database resulted in significantly higher species-level assignments (72.3%) of candidate species than the UNITE database (28.3-34.2%). Within each site, identification of candidate species ranged from 72.3-82.1% using the custom database; and 31.5-55.4% using the UNITE database. These results highlight that developing regional databases may accelerate a wide range of LFF research by improving our ability to characterize species-level diversity using DNA barcoding.
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Affiliation(s)
- Michael Kerr
- Department of Biology, Brigham Young University, Provo, UT 84602, USA
| | - Steven D Leavitt
- M.L. Bean Life Science Museum and Department of Biology, Brigham Young University, Provo, UT 84602, USA
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Leavitt SD, DeBolt A, McQuhae E, Allen JL. Genomic Resources for the First Federally Endangered Lichen: The Florida Perforate Cladonia ( Cladonia perforata). J Fungi (Basel) 2023; 9:698. [PMID: 37504687 PMCID: PMC10381751 DOI: 10.3390/jof9070698] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 06/18/2023] [Accepted: 06/19/2023] [Indexed: 07/29/2023] Open
Abstract
Thirty years after its designation as a federally endangered species, the Florida Perforate Cladonia (FPC) remains imperiled in isolated populations in the Florida scrub in the southeastern USA. For threatened and endangered species, such as FPC, reference genomes provide critical insight into genomic diversity, local adaptations, landscape-level genetics, and phylogenomics. Using high-throughput sequencing, we assemble the first draft nuclear and mitochondrial genomes for the FPC mycobiont-Cladonia perforata. We also assess genetic diversity within and among populations in southeastern Florida using genome-scale data and investigate diversity across the entire nuclear ribosomal cistron, including the standard DNA barcoding marker for fungi. The draft nuclear genome spanned 33.6 Mb, and the complete, circular mitochondrial genome was 59 Kb. We also generated the first chloroplast genome, to our knowledge, for the photobiont genus associated with FPC, an undescribed Asterochloris species. We inferred the presence of multiple, distinct mycobiont parental genotypes (genets) occurring at local scales in southeastern Florida, and strikingly, no genets were shared among even the closest sample sites. All sampled thalli shared identical mitochondrial genomes, while the nuclear ribosomal cistron showed limited variability-highlighting the genetic resolution provided by nuclear genome-scale datasets. The genomic resources generated here provide critical resources for informed conservation efforts for the FPC.
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Affiliation(s)
- Steven D Leavitt
- M.L. Bean Life Science Museum and Department of Biology, Brigham Young University, Provo, UT 84602, USA
| | - Ann DeBolt
- Department of Biology, Boise State University, Boise, ID 83725, USA
| | - Ethan McQuhae
- Plant and Wildlife Sciences, Brigham Young University, Provo, UT 84602, USA
| | - Jessica L Allen
- Department of Biology, Eastern Washington University, Cheney, WA 99004, USA
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van der Walt D, Steenkamp ET, Wingfield BD, Wilken PM. Evidence of Biparental Mitochondrial Inheritance from Self-Fertile Crosses between Closely Related Species of Ceratocystis. J Fungi (Basel) 2023; 9:686. [PMID: 37367622 DOI: 10.3390/jof9060686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 06/07/2023] [Accepted: 06/15/2023] [Indexed: 06/28/2023] Open
Abstract
Hybridization is recognized as a notable driver of evolution and adaptation, which closely related species may exploit in the form of incomplete reproductive barriers. Three closely related species of Ceratocystis (i.e., C. fimbriata, C. manginecans and C. eucalypticola) have previously been shown to hybridize. In such studies, naturally occurring self-sterile strains were mated with an unusual laboratory-generated sterile isolate type, which could have impacted conclusions regarding the prevalence of hybridization and inheritance of mitochondria. In the current study, we investigated whether interspecific crosses between fertile isolates of these three species are possible and, if so, how mitochondria are inherited by the progeny. For this purpose, a PCR-RFLP method and a mitochondrial DNA-specific PCR technique were custom-made. These were applied in a novel approach of typing complete ascospore drops collected from the fruiting bodies in each cross to distinguish between self-fertilizations and potential hybridization. These markers showed hybridization between C. fimbriata and C. eucalypticola and between C. fimbriata and C. manginecans, while no hybridization was detected in the crosses involving C. manginecans and C. eucalypticola. In both sets of hybrid progeny, we detected biparental inheritance of mitochondria. This study was the first to successfully produce hybrids from a cross involving self-fertile isolates of Ceratocystis and also provided the first direct evidence of biparental mitochondrial inheritance in the Ceratocystidaceae. This work lays the foundation for further research focused on investigating the role of hybridization in the speciation of Ceratocystis species and if mitochondrial conflict could have influenced the process.
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Affiliation(s)
- Daniella van der Walt
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria 0028, South Africa
| | - Emma T Steenkamp
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria 0028, South Africa
| | - Brenda D Wingfield
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria 0028, South Africa
| | - P Markus Wilken
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria 0028, South Africa
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Xian Q, Wang S, Liu Y, Kan S, Zhang W. Structure-Based GC Investigation Sheds New Light on ITS2 Evolution in Corydalis Species. Int J Mol Sci 2023; 24:ijms24097716. [PMID: 37175423 PMCID: PMC10178233 DOI: 10.3390/ijms24097716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 04/20/2023] [Accepted: 04/21/2023] [Indexed: 05/15/2023] Open
Abstract
Guanine and cytosine (GC) content is a fundamental component of genetic diversity and essential for phylogenetic analyses. However, the GC content of the ribosomal internal transcribed spacer 2 (ITS2) remains unknown, despite the fact that ITS2 is a widely used phylogenetic marker. Here, the ITS2 was high-throughput sequenced from 29 Corydalis species, and their GC contents were comparatively investigated in the context of ITS2's characteristic secondary structure and concerted evolution. Our results showed that the GC contents of ITS2 were 131% higher than those of their adjacent 5.8S regions, suggesting that ITS2 underwent GC-biased evolution. These GCs were distributed in a heterogeneous manner in the ITS2 secondary structure, with the paired regions being 130% larger than the unpaired regions, indicating that GC is chosen for thermodynamic stability. In addition, species with homogeneous ITS2 sequences were always GC-rich, supporting GC-biased gene conversion (gBGC), which occurred with ITS2's concerted evolution. The RNA substitution model inferred also showed a GC preference among base pair transformations, which again supports gBGC. Overall, structurally based GC investigation reveals that ITS2 evolves under structural stability and gBGC selection, significantly increasing its GC content.
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Affiliation(s)
- Qing Xian
- Marine College, Shandong University, Weihai 264209, China
| | - Suyin Wang
- Marine College, Shandong University, Weihai 264209, China
| | - Yanyan Liu
- College of Plant Protection, Henan Agricultural University, Zhengzhou 450002, China
| | - Shenglong Kan
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China
| | - Wei Zhang
- Marine College, Shandong University, Weihai 264209, China
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Sipiczki M, Hrabovszki V. Galactomyces candidus diversity in the complex mycobiota of cow-milk bryndza cheese comprising antagonistic and sensitive strains. Int J Food Microbiol 2023; 388:110088. [PMID: 36689829 DOI: 10.1016/j.ijfoodmicro.2023.110088] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 12/30/2022] [Accepted: 01/09/2023] [Indexed: 01/15/2023]
Abstract
Galactomyces candidus (orthographic variant: Galactomyces candidum) is a heterogeneous species of Saccharomycetales that comprises dimorphic yeasts described previously under various names (e.g. Geotrichum, Dipodascus). Its strains are common components of the cheese surface mycobiota. This study identified genetically and physiologically heterogeneous G. candidus strains in the complex mycobiota of artisanal cow-milk bryndza samples. The traditional Slovak bryndza is a cheese produced from ewe's milk in cooler mountainous regions and from cow's milk in warmer low-land regions. The taxonomic analysis of the culturable yeasts of the latter version carried out in this study revealed considerable differences from the yeast biota previously described for ovine bryndza. However, the conventional D1/D2- and ITS-based barcode analyses could not assign unanimously all isolates to species because of the intragenomic barcode diversity in certain groups and the discordance between the D1/D2 and ITS results in other groups. The identified species and groups of isolates had different abilities to utilise the carbon and energy sources (lactose, lactate, lipids and proteins) available in milk and ripening cheese. The G. candidus strains did not metabolise lactose and lactate, hydrolysed milk proteins with diverse, usually moderate efficiency and only could grow on certain amino acids as only energy sources. Their preferred substrate was lipid. Under aerobic conditions, its hyphae penetrated the lipid droplets and degraded their content from inside by developing a dense internal mycelium. Sporulation and different MLST (multilocus sequence typing) patterns indicated that the Galactomyces strains could sexually interact and their genomes could recombine. The Galactomyces and Kluyveromyces isolates had antagonistic effects against other members of the mycobiota.
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Affiliation(s)
- Matthias Sipiczki
- Department of Genetics and Applied Microbiology, University of Debrecen, Debrecen, Hungary.
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Vaghefi N, Kusch S, Németh MZ, Seress D, Braun U, Takamatsu S, Panstruga R, Kiss L. Beyond Nuclear Ribosomal DNA Sequences: Evolution, Taxonomy, and Closest Known Saprobic Relatives of Powdery Mildew Fungi ( Erysiphaceae) Inferred From Their First Comprehensive Genome-Scale Phylogenetic Analyses. Front Microbiol 2022; 13:903024. [PMID: 35756050 PMCID: PMC9218914 DOI: 10.3389/fmicb.2022.903024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 05/10/2022] [Indexed: 11/13/2022] Open
Abstract
Powdery mildew fungi (Erysiphaceae), common obligate biotrophic pathogens of many plants, including important agricultural and horticultural crops, represent a monophyletic lineage within the Ascomycota. Within the Erysiphaceae, molecular phylogenetic relationships and DNA-based species and genera delimitations were up to now mostly based on nuclear ribosomal DNA (nrDNA) phylogenies. This is the first comprehensive genome-scale phylogenetic analysis of this group using 751 single-copy orthologous sequences extracted from 24 selected powdery mildew genomes and 14 additional genomes from Helotiales, the fungal order that includes the Erysiphaceae. Representative genomes of all powdery mildew species with publicly available whole-genome sequencing (WGS) data that were of sufficient quality were included in the analyses. The 24 powdery mildew genomes included in the analysis represented 17 species belonging to eight out of 19 genera recognized within the Erysiphaceae. The epiphytic genera, all but one represented by multiple genomes, belonged each to distinct, well-supported lineages. Three hemiendophytic genera, each represented by a single genome, together formed the hemiendophytic lineage. Out of the 14 other taxa from the Helotiales, Arachnopeziza araneosa, a saprobic species, was the only taxon that grouped together with the 24 genome-sequenced powdery mildew fungi in a monophyletic clade. The close phylogenetic relationship between the Erysiphaceae and Arachnopeziza was revealed earlier by a phylogenomic study of the Leotiomycetes. Further analyses of powdery mildew and Arachnopeziza genomes may discover signatures of the evolutionary processes that have led to obligate biotrophy from a saprobic way of life. A separate phylogeny was produced using the 18S, 5.8S, and 28S nrDNA sequences of the same set of powdery mildew specimens and compared to the genome-scale phylogeny. The nrDNA phylogeny was largely congruent to the phylogeny produced using 751 orthologs. This part of the study has revealed multiple contamination and other quality issues in some powdery mildew genomes. We recommend that the presence of 28S, internal transcribed spacer (ITS), and 18S nrDNA sequences in powdery mildew WGS datasets that are identical to those determined by Sanger sequencing should be used to assess the quality of assemblies, in addition to the commonly used Benchmarking Universal Single-Copy Orthologs (BUSCO) values.
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Affiliation(s)
- Niloofar Vaghefi
- Centre for Crop Health, Institute for Life Sciences and the Environment, University of Southern Queensland, Toowoomba, QLD, Australia
- Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Stefan Kusch
- Unit of Plant Molecular Cell Biology, Institute for Biology I, RWTH Aachen University, Aachen, Germany
| | - Márk Z. Németh
- Plant Protection Institute, Centre for Agricultural Research, Eötvös Loránd Research Network, Budapest, Hungary
| | - Diána Seress
- Plant Protection Institute, Centre for Agricultural Research, Eötvös Loránd Research Network, Budapest, Hungary
| | - Uwe Braun
- Department of Geobotany and Botanical Garden, Herbarium, Institute for Biology, Martin Luther University of Halle-Wittenberg, Halle (Saale), Germany
| | - Susumu Takamatsu
- Laboratory of Plant Pathology, Faculty of Bioresources, Mie University, Tsu, Japan
| | - Ralph Panstruga
- Unit of Plant Molecular Cell Biology, Institute for Biology I, RWTH Aachen University, Aachen, Germany
| | - Levente Kiss
- Centre for Crop Health, Institute for Life Sciences and the Environment, University of Southern Queensland, Toowoomba, QLD, Australia
- Plant Protection Institute, Centre for Agricultural Research, Eötvös Loránd Research Network, Budapest, Hungary
- Centre for Research and Development, Eszterházy Károly Catholic University, Eger, Hungary
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Population Diversity and Genetic Structure Reveal Patterns of Host Association and Anthropogenic Impact for the Globally Important Fungal Tree Pathogen Ceratocystis manginecans. J Fungi (Basel) 2021; 7:jof7090759. [PMID: 34575797 PMCID: PMC8470894 DOI: 10.3390/jof7090759] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 09/10/2021] [Accepted: 09/12/2021] [Indexed: 11/17/2022] Open
Abstract
Species in the Ceratocystis manginecans complex are important fungal pathogens of plantation trees globally. The most important hosts include species of Eucalyptus, Acacia, Mangifera, and Punica. Despite their relevance and widespread occurrence, little is known regarding their population genetics and how this might relate to their host associations or geographic regions in which they occur. A global collection of 491 isolates representing the C. manginecans complex, from four different plant hosts and nine countries, were genotyped using microsatellite markers. Population genetic analyses using numerous tools were conducted to interrogate how their genetic diversity and structure might be affected by host or areas of occurrence. Results of genetic diversity studies showed that when grouping isolates into populations based on their host associations, the population on Eucalyptus was most diverse, and it also has a broad global distribution. When considering countries of origin as a basis for defining populations, the gene and genotypic diversity were highest in populations from China, Indonesia, and Brazil. In contrast, populations from Oman and Pakistan collected from Mangifera had the lowest genetic diversity and were clonal. Molecular variance, population differentiation, and network and structure analyses showed that the genetic structure of isolates in the C. manginecans complex is influenced by both host association as well as geographical isolation. Furthermore, the results reflected the movement of genotypes between plant hosts and geographic regions that have implications regarding the broad global distribution of this pathogen.
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Prahl RE, Khan S, Deo RC. The role of internal transcribed spacer 2 secondary structures in classifying mycoparasitic Ampelomyces. PLoS One 2021; 16:e0253772. [PMID: 34191835 PMCID: PMC8244850 DOI: 10.1371/journal.pone.0253772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Accepted: 06/13/2021] [Indexed: 11/19/2022] Open
Abstract
Many fungi require specific growth conditions before they can be identified. Direct environmental DNA sequencing is advantageous, although for some taxa, specific primers need to be used for successful amplification of molecular markers. The internal transcribed spacer region is the preferred DNA barcode for fungi. However, inter- and intra-specific distances in ITS sequences highly vary among some fungal groups; consequently, it is not a solely reliable tool for species delineation. Ampelomyces, mycoparasites of the fungal phytopathogen order Erysiphales, can have ITS genetic differences up to 15%; this may lead to misidentification with other closely related unknown fungi. Indeed, Ampelomyces were initially misidentified as other pycnidial mycoparasites, but subsequent research showed that they differ in pycnidia morphology and culture characteristics. We investigated whether the ITS2 nucleotide content and secondary structure was different between Ampelomyces ITS2 sequences and those unrelated to this genus. To this end, we retrieved all ITS sequences referred to as Ampelomyces from the GenBank database. This analysis revealed that fungal ITS environmental DNA sequences are still being deposited in the database under the name Ampelomyces, but they do not belong to this genus. We also detected variations in the conserved hybridization model of the ITS2 proximal 5.8S and 28S stem from two Ampelomyces strains. Moreover, we suggested for the first time that pseudogenes form in the ITS region of this mycoparasite. A phylogenetic analysis based on ITS2 sequences-structures grouped the environmental sequences of putative Ampelomyces into a different clade from the Ampelomyces-containing clades. Indeed, when conducting ITS2 analysis, resolution of genetic distances between Ampelomyces and those putative Ampelomyces improved. Each clade represented a distinct consensus ITS2 S2, which suggested that different pre-ribosomal RNA (pre-rRNA) processes occur across different lineages. This study recommends the use of ITS2 S2s as an important tool to analyse environmental sequencing and unveiling the underlying evolutionary processes.
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Affiliation(s)
- Rosa E. Prahl
- School of Sciences, University of Southern Queensland, Toowoomba, Queensland, Australia
- * E-mail:
| | - Shahjahan Khan
- School of Sciences, Centre for Health Research, Centre for Applied Climate Sciences, University of Southern Queensland, Toowoomba, Queensland, Australia
| | - Ravinesh C. Deo
- School of Sciences, University of Southern Queensland, Toowoomba, Queensland, Australia
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Suwandi S, Irsan C, Hamidson H, Umayah A, Asriyani KD. Identification and Characterization of Ceratocystis fimbriata Causing Lethal Wilt on the Lansium Tree in Indonesia. THE PLANT PATHOLOGY JOURNAL 2021; 37:124-136. [PMID: 33866755 PMCID: PMC8053844 DOI: 10.5423/ppj.oa.08.2020.0147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 01/25/2021] [Accepted: 01/25/2021] [Indexed: 06/12/2023]
Abstract
Bark canker, wood discoloration, and wilting of the duku tree (Lansium domesticum) along the watershed of Komering River, South Sumatra Province, Indonesia first appeared in 2013. The incidence of tree mortality was 100% within 3 years in badly infected orchards. A Ceratocystis species was consistently isolated from the diseased tissue and identified by morphological and sequence analyses of the internal transcribed spacer (ITS) and β-tubulin regions. Pathogenicity tests were conducted and Koch's postulates were confirmed. The fungus was also pathogenic on Acacia mangium, but was less pathogenic on mango. Partial flooding was unfavourable for disease development. Two described isolates (WRC and WBC) had minor variation in morphology and DNA sequences, but the former exhibited a more pathogenic on both duku and acacia. The ITS phylogenies grouped the most pathogenic isolate (WRC) causing wilting of the duku tree within the aggressive and widely distributed ITS5 haplotype of C. fimbriata.
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Conti A, Corte L, Casagrande Pierantoni D, Robert V, Cardinali G. What Is the Best Lens? Comparing the Resolution Power of Genome-Derived Markers and Standard Barcodes. Microorganisms 2021; 9:microorganisms9020299. [PMID: 33540579 PMCID: PMC7912933 DOI: 10.3390/microorganisms9020299] [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: 12/30/2020] [Revised: 01/22/2021] [Accepted: 01/29/2021] [Indexed: 02/07/2023] Open
Abstract
Fungal species delimitation was traditionally carried out with multicopy ribosomal RNA (rRNA) genes, principally for their ease of amplification. Since the efficacy of these markers has been questioned, single-copy protein-encoding genes have been proposed alone or in combination for Multi-Locus Sequence Typing (MLST). In this context, the role of the many sequences obtained with Next-Generation Sequencing (NGS) techniques, in both genomics and metagenomics, further pushes toward an analysis of the efficacy of NGS-derived markers and of the metrics to evaluate the marker efficacy in discriminating fungal species. This paper aims at proposing MeTRe (Mean Taxonomic Resolution), a novel index that could be used both for measuring marker efficacy and for assessing the actual resolution (i.e., the level of separation) between species obtained with different markers or their combinations. In this paper, we described and then employed this index to compare the efficacy of two rRNAs and four single-copy markers obtained from public databases as both an amplicon-based approach and genome-derived sequences. Two different groups of species were used, one with a pathogenic species of Candida that was characterized by relatively well-separated taxa, whereas the other, comprising some relevant species of the sensu stricto group of the genus Saccharomyces, included close species and interspecific hybrids. The results showed the ability of MeTRe to evaluate marker efficacy in general and genome-derived markers specifically.
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Affiliation(s)
- Angela Conti
- Department of Pharmaceutical Sciences, University of Perugia, 06121 Perugia, Italy; (A.C.); (L.C.); (D.C.P.)
| | - Laura Corte
- Department of Pharmaceutical Sciences, University of Perugia, 06121 Perugia, Italy; (A.C.); (L.C.); (D.C.P.)
| | | | - Vincent Robert
- Westerdjik Institute for Biodiversity, 3584 Utrecht, The Netherlands;
| | - Gianluigi Cardinali
- Department of Pharmaceutical Sciences, University of Perugia, 06121 Perugia, Italy; (A.C.); (L.C.); (D.C.P.)
- CEMIN Excellence Research Centre, 06123 Perugia, Italy
- Correspondence:
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Rosazlina R, Jacobsen N, Ørgaard M, Othman AS. Molecular evidence of the hybrid origin of Cryptocoryne ×purpurea Ridl. nothovar. purpurea (Araceae). PLoS One 2021; 16:e0239499. [PMID: 33476321 PMCID: PMC7819605 DOI: 10.1371/journal.pone.0239499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 11/12/2020] [Indexed: 11/18/2022] Open
Abstract
Natural hybridization has been considered a source of taxonomic complexity in Cryptocoryne. A combined study of DNA sequencing data from the internal transcribed spacer (ITS) of nuclear ribosomal DNA and the trnK-matK region of chloroplast DNA was used to identify the parents of Cryptocoryne putative hybrids from Peninsular Malaysia. Based on the intermediate morphology and sympatric distribution area, the plants were tentatively identified as the hybrid Cryptocoryne ×purpurea nothovar. purpurea. The plants were pollen sterile and had long been considered as hybrids, supposedly between two related and co-existing species, C. cordata var. cordata and C. griffithii. The status of C. ×purpurea nothovar. purpurea was independently confirmed by the presence of an additive ITS sequence pattern from these two parental species in hybrid individuals. An analysis of the chloroplast trnK-matK sequences showed that the hybridization is bidirectional with the putative hybrids sharing identical sequences from C. cordata var. cordata and C. griffithii, indicating that both putative parental species had been the maternal parent in different accessions.
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Affiliation(s)
- Rusly Rosazlina
- School of Biological Sciences, University Sains Malaysia, Minden, Penang, Malaysia
- * E-mail: (RR); (ASO)
| | - Niels Jacobsen
- Department of Plant and Environmental Sciences, Section of Organismal Biology, Faculty of Science, University of Copenhagen, Frederiksberg C, Copenhagen, Denmark
| | - Marian Ørgaard
- Department of Plant and Environmental Sciences, Section of Organismal Biology, Faculty of Science, University of Copenhagen, Frederiksberg C, Copenhagen, Denmark
| | - Ahmad Sofiman Othman
- School of Biological Sciences, University Sains Malaysia, Minden, Penang, Malaysia
- * E-mail: (RR); (ASO)
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De Luca D, Kooistra WHCF, Sarno D, Biffali E, Piredda R. Empirical evidence for concerted evolution in the 18S rDNA region of the planktonic diatom genus Chaetoceros. Sci Rep 2021; 11:807. [PMID: 33437054 PMCID: PMC7804092 DOI: 10.1038/s41598-020-80829-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 12/28/2020] [Indexed: 11/08/2022] Open
Abstract
Concerted evolution is a process of homogenisation of repetitive sequences within a genome through unequal crossing over and gene conversion. This homogenisation is never fully achieved because mutations always create new variants. Classically, concerted evolution has been detected as "noise" in electropherograms and these variants have been characterised through cloning and sequencing of subsamples of amplified products. However, this approach limits the number of detectable variants and provides no information about the abundance of each variant. In this study, we investigated concerted evolution by using environmental time-series metabarcoding data, single strain high-throughput sequencing (HTS) and a collection of Sanger reference barcode sequences. We used six species of the marine planktonic diatom genus Chaetoceros as study system. Abundance plots obtained from environmental metabarcoding and single strain HTS showed the presence of a haplotype far more abundant than all the others (the "dominant" haplotype) and identical to the reference sequences of that species obtained with Sanger sequencing. This distribution fitted best with Zipf's law among the rank abundance/ dominance models tested. Furthermore, in each strain 99% of reads showed a similarity of 99% with the dominant haplotype, confirming the efficiency of the homogenisation mechanism of concerted evolution. We also demonstrated that minor haplotypes found in the environmental samples are not only technical artefacts, but mostly intragenomic variation generated by incomplete homogenisation. Finally, we showed that concerted evolution can be visualised inferring phylogenetic networks from environmental data. In conclusion, our study provides an important contribution to the understanding of concerted evolution and to the interpretation of DNA barcoding and metabarcoding data based on multigene family markers.
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Affiliation(s)
- Daniele De Luca
- Department of Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121, Naples, Italy.
- Department of Biology, University of Naples Federico II, Botanical Garden of Naples, Via Foria 223, 80139, Naples, Italy.
| | - Wiebe H C F Kooistra
- Department of Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121, Naples, Italy
| | - Diana Sarno
- Department of Research Infrastructure for Marine Biological Resources, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121, Naples, Italy
| | - Elio Biffali
- Department of Research Infrastructure for Marine Biological Resources, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121, Naples, Italy
| | - Roberta Piredda
- Department of Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121, Naples, Italy.
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16
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Gubanova A, Drapun I, Garbazey O, Krivenko O, Vodiasova E. Pseudodiaptomus marinus Sato, 1913 in the Black Sea: morphology, genetic analysis, and variability in seasonal and interannual abundance. PeerJ 2020; 8:e10153. [PMID: 33150076 PMCID: PMC7585723 DOI: 10.7717/peerj.10153] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 09/21/2020] [Indexed: 12/02/2022] Open
Abstract
Calanoid copepod Peudodiaptomus marinus Sato, 1913 was first recorded in Sevastopol Bay in the northern Black Sea in September 2016. We performed regular observations of this new invasive species between October 2016 and December 2018. We conducted bi-weekly plankton sampling at three stations located within or adjacent to Sevastopol Bay. This is the first paper to combine (i) a detailed morphological study, (ii) molecular genetic analysis, and (iii) an investigation of P. marinus seasonal dynamics and interannual abundance variability in the coastal Black Sea. Our morphological research showed similarities between Pseudodiaptomus specimens and existing P. marinus illustrations and descriptions. Our morphological analysis results were confirmed using molecular genetic studies. Based on the genetic variability of ITS2 and cytb, we found that all investigated specimens from Sevastopol Bay belonged to P. marinus. Investigations of P. marinus seasonal and interannual abundance variability showed the same seasonal patterns throughout the studied period, with a higher seasonal abundance from October to November and one pronounced density peak in autumn. The highest abundances (2,000 ind m–3 at the mouth of the bay and more than 5,000 ind m–3at its centre) were recorded in November 2018. In the samples, we found adults of both sexes, including ovigerous females, copepodites I–V, and nauplii, suggesting that the species reproduce in Sevastopol Bay. Our research indicated that P. marinus is a new non-indigenous species (NIS) in the Black Sea, and we will discuss a possible vector of its introduction into this basin.
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Affiliation(s)
- Alexandra Gubanova
- Plankton department, A.O. Kovalevsky Institute of Biology of the Southern Seas of RAS, Sevastopol, Russia
| | - Inna Drapun
- Plankton department, A.O. Kovalevsky Institute of Biology of the Southern Seas of RAS, Sevastopol, Russia
| | - Oksana Garbazey
- Plankton department, A.O. Kovalevsky Institute of Biology of the Southern Seas of RAS, Sevastopol, Russia
| | - Olga Krivenko
- Marine biodiversity and functional genomics laboratory, A.O. Kovalevsky Institute of Biology of the Southern Seas of RAS, Sevastopol, Russia
| | - Ekaterina Vodiasova
- Marine biodiversity and functional genomics laboratory, A.O. Kovalevsky Institute of Biology of the Southern Seas of RAS, Sevastopol, Russia
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17
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Borowska‐Zuchowska N, Kovarik A, Robaszkiewicz E, Tuna M, Tuna GS, Gordon S, Vogel JP, Hasterok R. The fate of 35S rRNA genes in the allotetraploid grass Brachypodium hybridum. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 103:1810-1825. [PMID: 32506573 PMCID: PMC7497271 DOI: 10.1111/tpj.14869] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 05/20/2020] [Accepted: 05/28/2020] [Indexed: 05/22/2023]
Abstract
Nucleolar dominance (ND) consists of the reversible silencing of 35S/45S rDNA loci inherited from one of the ancestors of an allopolyploid. The molecular mechanisms by which one ancestral rDNA set is selected for silencing remain unclear. We applied a combination of molecular (Southern blot hybridization and reverse-transcription cleaved amplified polymorphic sequence analysis), genomic (analysis of variants) and cytogenetic (fluorescence in situ hybridization) approaches to study the structure, expression and epigenetic landscape of 35S rDNA in an allotetraploid grass that exhibits ND, Brachypodium hybridum (genome composition DDSS), and its putative progenitors, Brachypodium distachyon (DD) and Brachypodium stacei (SS). In progenitor genomes, B. stacei showed a higher intragenomic heterogeneity of rDNA compared with B. distachyon. In all studied accessions of B. hybridum, there was a reduction in the copy number of S homoeologues, which was accompanied by their inactive transcriptional status. The involvement of DNA methylation in CG and CHG contexts in the silencing of the S-genome rDNA loci was revealed. In the B. hybridum allotetraploid, ND is stabilized towards the D-genome units, irrespective of the polyphyletic origin of the species, and does not seem to be influenced by homoeologous 35S rDNA ratios and developmental stage.
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Affiliation(s)
- Natalia Borowska‐Zuchowska
- Plant Cytogenetics and Molecular Biology Group, Institute of Biology, Biotechnology and Environmental ProtectionFaculty of Natural SciencesUniversity of Silesia in KatowiceJagiellonska 28Katowice40‐032Poland
| | - Ales Kovarik
- Department of Molecular EpigeneticsInstitute of BiophysicsAcademy of Sciences of the Czech Republic, v.v.i.Královopolská 135Brno612 65Czech Republic
| | - Ewa Robaszkiewicz
- Plant Cytogenetics and Molecular Biology Group, Institute of Biology, Biotechnology and Environmental ProtectionFaculty of Natural SciencesUniversity of Silesia in KatowiceJagiellonska 28Katowice40‐032Poland
| | - Metin Tuna
- Department of Field CropsFaculty of AgricultureTekirdag Namik Kemal UniversitySuleymanpasaTekirdag59030Turkey
| | | | - Sean Gordon
- US Department of Energy (DOE) Joint Genome Institute (JGI)BerkeleyCA94720USA
| | - John P. Vogel
- US Department of Energy (DOE) Joint Genome Institute (JGI)BerkeleyCA94720USA
- University CaliforniaBerkeley, BerkeleyCA94720USA
| | - Robert Hasterok
- Plant Cytogenetics and Molecular Biology Group, Institute of Biology, Biotechnology and Environmental ProtectionFaculty of Natural SciencesUniversity of Silesia in KatowiceJagiellonska 28Katowice40‐032Poland
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18
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Sipiczki M. Metschnikowia pulcherrima and Related Pulcherrimin-Producing Yeasts: Fuzzy Species Boundaries and Complex Antimicrobial Antagonism. Microorganisms 2020; 8:E1029. [PMID: 32664630 PMCID: PMC7409158 DOI: 10.3390/microorganisms8071029] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 07/08/2020] [Accepted: 07/10/2020] [Indexed: 12/30/2022] Open
Abstract
Yeasts affiliated with the Metschnikowia pulcherrima clade (subclade) of the large ascomycetous genus Metschnikowia frequently turn out to produce the characteristic maroon-red pulcherrimin when tested for pigment production and prove to exert antagonistic effects on many types of microorganisms. The determination of the exact taxonomic position of the strains is hampered by the shortage of distinctive morphological and physiological properties of the species of the clade and the lack of rDNA barcode gaps. The rDNA repeats of the type strains of the species are not homogenized and are assumed to evolve by a birth-and-death mechanism combined with reticulation. The taxonomic division is further hampered by the incomplete biological (reproductive) isolation of the species: certain type strains can be hybridized and genome sequencing revealed chimeric genome structures in certain strains that might have evolved from interspecies hybrids (alloploid genome duplication). Various mechanisms have been proposed for the antimicrobial antagonism. One is related to pulcherrimin production. The diffusible precursor of pulcherrimin, the pulcherriminic acid is secreted by the cells into the environment where it forms the insoluble pulcherrimin with the ferric ions. The lack of free iron caused by the immobilization of ferric ions inhibits the growth of many microorganisms. Recent results of research into the complexity of the taxonomic division of the pulcherrimin-producing Metschnikowia yeasts and the mechanism(s) underlying their antimicrobial antagonism are discussed in this review.
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Affiliation(s)
- Matthias Sipiczki
- Department of Genetics and Applied Microbiology, University of Debrecen, 4032 Debrecen, Hungary
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19
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Species, Sequence Types and Alleles: Dissecting Genetic Variation in Acanthamoeba. Pathogens 2020; 9:pathogens9070534. [PMID: 32630775 PMCID: PMC7400246 DOI: 10.3390/pathogens9070534] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 06/29/2020] [Accepted: 06/30/2020] [Indexed: 12/15/2022] Open
Abstract
Species designations within Acanthamoeba are problematic because of pleomorphic morphology. Molecular approaches, including DNA sequencing, hinted at a resolution that has yet to be fully achieved. Alternative approaches were required. In 1996, the Byers/Fuerst lab introduced the concept of sequence types. Differences between isolates of Acanthamoeba could be quantitatively assessed by comparing sequences of the nuclear 18S rRNA gene, ultimately producing 22 sequence types, designated T1 through T22. The concept of sequence types helps our understanding of Acanthamoeba evolution. Nevertheless, substantial variation in the 18S rRNA gene differentiates many isolates within each sequence type. Because the majority of isolates with sequences in the international DNA databases have been studied for only a small segment of the gene, designated ASA.S1, genetic variation within this hypervariable region of the 18S rRNA gene has been scrutinized. In 2002, we first categorized variation in this region in a sample of T3 and T4 isolates from Hong Kong, observing ten “alleles” within type T4 and five “alleles” within T3. Subsequently, confusion occurred when different labs applied redundant numerical labels to identify different alleles. A more unified approach was required. We have tabulated alleles occurring in the sequences submitted to the international DNA databases, and determined their frequencies. Over 150 alleles have occurred more than once within 3500+ isolates of sequence type T4. Results from smaller samples of other sequence types (T3, T5, T11 and T15, and supergroup T2/6) have also been obtained. Our results provide new insights into the evolutionary history of Acanthamoeba, further illuminating the degree of genetic separation between significant taxonomic units within the genus, perhaps eventually elucidating what constitutes a species of Acanthamoeba.
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20
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Kanzi AM, Trollip C, Wingfield MJ, Barnes I, Van der Nest MA, Wingfield BD. Phylogenomic incongruence in Ceratocystis: a clue to speciation? BMC Genomics 2020; 21:362. [PMID: 32408859 PMCID: PMC7222570 DOI: 10.1186/s12864-020-6772-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 05/06/2020] [Indexed: 11/26/2022] Open
Abstract
Background The taxonomic history of Ceratocystis, a genus in the Ceratocystidaceae, has been beset with questions and debate. This is due to many of the commonly used species recognition concepts (e.g., morphological and biological species concepts) providing different bases for interpretation of taxonomic boundaries. Species delineation in Ceratocystis primarily relied on genealogical concordance phylogenetic species recognition (GCPSR) using multiple standard molecular markers. Results Questions have arisen regarding the utility of these markers e.g., ITS, BT and TEF1-α due to evidence of intragenomic variation in the ITS, as well as genealogical incongruence, especially for isolates residing in a group referred to as the Latin-American clade (LAC) of the species. This study applied a phylogenomics approach to investigate the extent of phylogenetic incongruence in Ceratocystis. Phylogenomic analyses of a total of 1121 shared BUSCO genes revealed widespread incongruence within Ceratocystis, particularly within the LAC, which was typified by three equally represented topologies. Comparative analyses of the individual gene trees revealed evolutionary patterns indicative of hybridization. The maximum likelihood phylogenetic tree generated from the concatenated dataset comprised of 1069 shared BUSCO genes provided improved phylogenetic resolution suggesting the need for multiple gene markers in the phylogeny of Ceratocystis. Conclusion The incongruence observed among single gene phylogenies in this study call into question the utility of single or a few molecular markers for species delineation. Although this study provides evidence of interspecific hybridization, the role of hybridization as the source of discordance will require further research because the results could also be explained by high levels of shared ancestral polymorphism in this recently diverged lineage. This study also highlights the utility of BUSCO genes as a set of multiple orthologous genes for phylogenomic studies.
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Affiliation(s)
- Aquillah M Kanzi
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria, South Africa.
| | - Conrad Trollip
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria, South Africa.,School of Applied Systems Biology, La Trobe University, Bundoora, Victoria, Australia.,Agriculture Victoria Research, Department of Jobs, Precincts and Regions, AgriBio Centre, Bundoora, Australia
| | - Michael J Wingfield
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria, South Africa
| | - Irene Barnes
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria, South Africa
| | - Magriet A Van der Nest
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria, South Africa.,Biotechnology Platform, Agricultural Research Council, Onderstepoort Campus, Pretoria, South Africa
| | - Brenda D Wingfield
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria, South Africa
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21
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Tremble K, Suz LM, Dentinger BTM. Lost in translation: Population genomics and long-read sequencing reveals relaxation of concerted evolution of the ribosomal DNA cistron. Mol Phylogenet Evol 2020; 148:106804. [PMID: 32247883 DOI: 10.1016/j.ympev.2020.106804] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 03/17/2020] [Accepted: 03/18/2020] [Indexed: 12/31/2022]
Abstract
Concerted evolution of the ribosomal DNA array has been studied in numerous eukaryotic taxa, yet is still poorly understood. rDNA genes are repeated dozens to hundreds of times in the eukaryotic genome (Eickbush and Eickbush, 2007) and it is believed that these arrays are homogenized through concerted evolution (Zimmer et al., 1980; Dover, 1993) preventing the accumulation of intragenomic, and intraspecific, variation. However, numerous studies have reported rampant intragenomic and intraspecific variation in the rDNA array (Ganley and Kobayashi, 2011; Naidoo et al., 2013; Hughes and Petersen, 2001; Lindner and Banik, 2011; Li et al., 2013; Lindner et al., 2013; Hughes et al., 2018), contradicting our current understanding of concerted evolution. The internal transcribed spacers (ITS) of the rDNA cistron are the most commonly used DNA barcoding region in Fungi (Schoch et al., 2012), and rely on concerted evolution to homogenize the rDNA array leading to a "barcode gap" (Puillandre et al., 2012). Here we show that in Boletus edulis Bull., ITS intragenomic variation persists at low allele frequencies throughout the rDNA array, this variation does not correlate with genomic relatedness between populations, and rDNA genes may not evolve in a strictly concerted fashion despite the presence of unequal recombination and gene conversion. Under normal assumptions, heterozygous positions found in ITS sequences represent hybridization between populations, yet through allelic mapping of the rDNA array we found numerous heterozygous alleles to be stochastically introgressed throughout, presenting a dishonest signal of gene flow. Moreover, despite the signal of gene flow in ITS, our organisms were highly inbred, indicating a disconnect between true gene flow and barcoding signals. In addition, we show that while the mechanisms of concerted evolution are ongoing in pseudo-heterozygous individuals, they are not fully homogenizing the ITS array. Concerted evolution of the rDNA array may insufficiently homogenize the ITS gene, allowing for misleading signals of gene flow to persist, vastly complicating the use of the ITS locus for DNA barcoding in Fungi.
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Affiliation(s)
- Keaton Tremble
- School of Biological Sciences, University of Utah, 257 1400 E, Salt Lake City, UT 84112, USA; Natural History Museum of Utah, University of Utah, 301 Wakara Way, Salt Lake City, UT 84108, USA.
| | - Laura M Suz
- Comparative Plant and Fungal Biology, Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3DS, UK
| | - Bryn T M Dentinger
- School of Biological Sciences, University of Utah, 257 1400 E, Salt Lake City, UT 84112, USA; Natural History Museum of Utah, University of Utah, 301 Wakara Way, Salt Lake City, UT 84108, USA.
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Bradshaw M, Grewe F, Thomas A, Harrison CH, Lindgren H, Muggia L, St Clair LL, Lumbsch HT, Leavitt SD. Characterizing the ribosomal tandem repeat and its utility as a DNA barcode in lichen-forming fungi. BMC Evol Biol 2020; 20:2. [PMID: 31906844 PMCID: PMC6945747 DOI: 10.1186/s12862-019-1571-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Accepted: 12/19/2019] [Indexed: 02/08/2023] Open
Abstract
Background Regions within the nuclear ribosomal operon are a major tool for inferring evolutionary relationships and investigating diversity in fungi. In spite of the prevalent use of ribosomal markers in fungal research, central features of nuclear ribosomal DNA (nrDNA) evolution are poorly characterized for fungi in general, including lichenized fungi. The internal transcribed spacer (ITS) region of the nrDNA has been adopted as the primary DNA barcode identification marker for fungi. However, little is known about intragenomic variation in the nrDNA in symbiotic fungi. In order to better understand evolution of nrDNA and the utility of the ITS region for barcode identification of lichen-forming fungal species, we generated nearly complete nuclear ribosomal operon sequences from nine species in the Rhizoplaca melanophthalma species complex using short reads from high-throughput sequencing. Results We estimated copy numbers for the nrDNA operon, ranging from nine to 48 copies for members of this complex, and found low levels of intragenomic variation in the standard barcode region (ITS). Monophyly of currently described species in this complex was supported in phylogenetic inferences based on the ITS, 28S, intergenic spacer region, and some intronic regions, independently; however, a phylogenetic inference based on the 18S provided much lower resolution. Phylogenetic analysis of concatenated ITS and intergenic spacer sequence data generated from 496 specimens collected worldwide revealed previously unrecognized lineages in the nrDNA phylogeny. Conclusions The results from our study support the general assumption that the ITS region of the nrDNA is an effective barcoding marker for fungi. For the R. melanophthalma group, the limited amount of potential intragenomic variability in the ITS region did not correspond to fixed diagnostic nucleotide position characters separating taxa within this species complex. Previously unrecognized lineages inferred from ITS sequence data may represent undescribed species-level lineages or reflect uncharacterized aspects of nrDNA evolution in the R. melanophthalma species complex.
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Affiliation(s)
- Michael Bradshaw
- Department of Biology, Brigham Young University, 4102 Life Science Building, Provo, UT, 84602, USA
| | - Felix Grewe
- Grainger Bioinformatics Center, The Field Museum, Chicago, IL, USA
| | - Anne Thomas
- Department of Biology, Brigham Young University, 4102 Life Science Building, Provo, UT, 84602, USA
| | - Cody H Harrison
- Department of Biology, Brigham Young University, 4102 Life Science Building, Provo, UT, 84602, USA
| | | | - Lucia Muggia
- Department of Life Sciences, University of Trieste, via Giorgieri 10, 34127, Trieste, Italy
| | - Larry L St Clair
- Department of Biology, Brigham Young University, 4102 Life Science Building, Provo, UT, 84602, USA.,M. L. Bean Life Science Museum, Brigham Young University, 4102 Life Science Building, Provo, UT, 84602, USA
| | | | - Steven D Leavitt
- Department of Biology, Brigham Young University, 4102 Life Science Building, Provo, UT, 84602, USA. .,M. L. Bean Life Science Museum, Brigham Young University, 4102 Life Science Building, Provo, UT, 84602, USA.
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de Souza TB, Gaeta ML, Martins C, Vanzela ALL. IGS sequences in Cestrum present AT- and GC-rich conserved domains, with strong regulatory potential for 5S rDNA. Mol Biol Rep 2019; 47:55-66. [PMID: 31571109 DOI: 10.1007/s11033-019-05104-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 09/24/2019] [Indexed: 11/28/2022]
Abstract
The 35S and 5S ribosomal DNA (rDNA) organized in thousands of copies in genomes, have been widely used in numerous comparative cytogenetic studies. Nevertheless, several questions related to the diversity and organization of regulatory motifs in 5S rDNA remain to be addressed. The 5S rDNA unit is composed of a conserved 120 bp length coding region and an intergenic spacer (IGS) containing potential regulatory motifs (Poly-T, AT-rich and GC-rich) differing in number, redundancy and position along the IGS. The Cestrum species (Solanaceae) have large genomes (about 10 pg/1C) and conserved 2n = 16 karyotypes. Strikingly, these genomes show high diversity of heterochromatin distribution, variability in 35S rDNA loci and the occurrence of B chromosomes. However, the 5S rDNA loci are highly conserved in the proximal region of chromosome 8. Comparison of seventy-one IGS sequences in plants revealed several conserved motifs with potential regulatory function. The AT- and GC-rich domains appeared highly conserved in Cestrum chromosomes. The 5S genic and the GC-rich IGS probe produced FISH signals in both A (pair 8) and B chromosomes. The GC-rich domain presented a strong potential for regulation because it may be associated with CpG islands organization, as well as to hairpin and loop organization. Another interesting aspect was the ability of AT- and GC-rich motifs to produce non-heterochromatic CMA/DAPI signals. While the length of the 5S rDNA IGS region varied in size between the Cestrum species, the individual sequence motifs seem to be conserved suggesting their regulatory function. The most striking feature was the conserved GC-rich domain in Cestrum, which is recognized as a signature trait of the proximal region of chromosome pair 8.
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Affiliation(s)
- Thaíssa Boldieri de Souza
- Laboratório de Citogenética e Diversidade Vegetal, Departamento de Biologia Geral, Centro de Ciências Biológicas, Universidade Estadual de Londrina, Londrina, Paraná, 86057-970, Brazil
| | - Marcos Letaif Gaeta
- Laboratório de Citogenética e Diversidade Vegetal, Departamento de Biologia Geral, Centro de Ciências Biológicas, Universidade Estadual de Londrina, Londrina, Paraná, 86057-970, Brazil
| | - Cesar Martins
- Departamento de Morfologia, Instituto de Biociências, Universidade Estadual Paulista (UNESP), Botucatu, SP, CEP 18618689, Brazil
| | - André Luís Laforga Vanzela
- Laboratório de Citogenética e Diversidade Vegetal, Departamento de Biologia Geral, Centro de Ciências Biológicas, Universidade Estadual de Londrina, Londrina, Paraná, 86057-970, Brazil.
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Zalar P, Zupančič J, Gostinčar C, Zajc J, de Hoog GS, De Leo F, Azua-Bustos A, Gunde-Cimerman N. The extremely halotolerant black yeast Hortaea werneckii - a model for intraspecific hybridization in clonal fungi. IMA Fungus 2019; 10:10. [PMID: 32647617 PMCID: PMC7325687 DOI: 10.1186/s43008-019-0007-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 04/03/2019] [Indexed: 12/22/2022] Open
Abstract
The polymorphic black yeast Hortaea werneckii (Capnodiales, Ascomycota) is extremely halotolerant (growth from 0 to 30% [w/v] NaCl) and has been extensively studied as a model for halotolerance in Eukaryotes for over two decades. Its most frequent sources are hypersaline environments and adjacent sea-water habitats in temperate, subtropical and tropical climates. Although typically saprobic, H. werneckii can also act as a commensal coloniser on human skin, causing tinea nigra on hands and soles. Here, we report that addition of NaCl to culture media expands the growth range of H. werneckii to 37 °C, which explains its colonisation of human skin, with its increased salinity. The morphological and physiological plasticity/ versatility of H. werneckii indicate that a species complex might be involved. This was investigated in this polyphasic taxonomic analysis based on the global diversity of H. werneckii strains collected from hypersaline environments, and from humans and animals. Analysis of D1/D2domains of 28S and internal transcribed spacer rDNA revealed 10 and 17 genotypes, respectively, that were not always compliant. The genotypes have global distributions. Human and environmental strains with the same genotypes are intermingled. Due to the limited number of phylogenetically informative characters in the ribosomal DNA dataset, the partial genes encoding for β-tubulin (BTB) and mini-chromosome maintenance protein (MCM7) were also sequenced. The use of these genes was hampered by ambiguous sequences obtained by Sanger sequencing, as a consequence of the diploid and highly heterozygous genome of many H. werneckii strains. Analysis of the BTB and MCM7 genes showed that in some cases two copies of the gene from the same genome are positioned in distant phylogenetic clusters of the intraspecific gene tree. Analysis of whole-genome sequences of selected H. werneckii strains generally confirmed the phylogenetic distances estimated on the basis of ribosomal genes, but also showed substantial reticulation within the phylogenetic history of the strains. This is in line with the hypothesis that the diploid genomes of H. werneckii were formed by hybridizations, which have sometimes occurred between relatively divergent strains.
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Affiliation(s)
- Polona Zalar
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, SI-1000 Ljubljana, Slovenia
| | - Jerneja Zupančič
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, SI-1000 Ljubljana, Slovenia
| | - Cene Gostinčar
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, SI-1000 Ljubljana, Slovenia
- Lars Bolund Institute of Regenerative Medicine, BGI-Qingdao, Qingdao, 266555 China
| | - Janja Zajc
- Department of Biotechnology and Systems Biology, National Institute of Biology, Večna pot 111, 1000 Ljubljana, Slovenia
| | - G. Sybren de Hoog
- Westerdijk Fungal Biodiversity Institute, P.O. Box 85167, Utrecht, 3508 AD The Netherlands
- Centre of Expertise in Mycology of RadboudUMC, Canisius Wilhelmina Hospital, Nijmegen, The Netherlands
| | - Filomena De Leo
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences (ChiBioFarAm), University of Messina, Viale F. Stagno d’Alcontres, 31 98166 Messina, Italy
| | - Armando Azua-Bustos
- Centro de Astrobiología (CSIC-INTA), Madrid, Spain
- Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, 8910060 Santiago, Chile
| | - Nina Gunde-Cimerman
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, SI-1000 Ljubljana, Slovenia
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Gong L, Luo H, Shi W, Yang M. Intra-individual variation and transcribed pseudogenes in the ribosomal ITS1-5.8S-ITS2 rDNA of Paraplagusia japonica (Pleuronectiformes: Cynoglossidae). Biochem Biophys Res Commun 2019; 513:726-731. [DOI: 10.1016/j.bbrc.2019.04.064] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 04/09/2019] [Indexed: 10/27/2022]
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26
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Rodionov AV, Dobryakova KS, Punina EO. Polymorphic Sites in ITS1-5.8S rDNA-ITS2 Region in Hybridogenic Genus × Elyhordeum and Putative Interspecific Hybrids Elymus (Poaceae: Triticeae). RUSS J GENET+ 2018. [DOI: 10.1134/s1022795418090120] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Roscini L, Tristezza M, Corte L, Colabella C, Perrotta C, Rampino P, Robert V, Vu D, Cardinali G, Grieco F. Early Ongoing Speciation of Ogataea uvarum Sp. Nov. Within the Grape Ecosystem Revealed by the Internal Variability Among the rDNA Operon Repeats. Front Microbiol 2018; 9:1687. [PMID: 30123190 PMCID: PMC6085423 DOI: 10.3389/fmicb.2018.01687] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Accepted: 07/06/2018] [Indexed: 11/13/2022] Open
Abstract
A yeast strain was isolated during a study on vineyard-associated yeast strains from Apulia in Southern Italy. ITS and LSU D1/D2 rDNA sequences showed this strain not to belong to any known species and was described as the type strain of Ogataea uvarum sp. nov., a close relative of O. philodendri. Several secondary peaks appeared in the sequences, suggesting internal heterogeneity among the copies of the rDNA. This hypothesis was tested by sequencing single clones of the marker region. The analyses showed different levels of variability throughout the operon with differences between the rRNA encoding genes and the internally transcribed regions. O. uvarum and O. philodendri share high frequency variants, i.e., variants frequently found in many clones, whereas there is a large variability of the low frequency polymorphisms, suggesting that the mechanism of homogenization is more active with the former than with the latter type of variation. These findings indicate that low frequency variants are detected in Sanger sequencing as secondary peaks whereas in Next Generation Sequencing (NGS) of metagenomics DNA would lead to an overestimate of the alpha diversity. For the first time in our knowledge, this investigation shed light on the variation of the copy number of the rDNA cistron during the yeast speciation process. These polymorphisms can be used to investigate on the processes occurring in these taxonomic markers during the separation of fungal species, it being a genetic process highly frequent in the complex microbial ecosystem existing in grape, must and wine.
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Affiliation(s)
- Luca Roscini
- Department of Pharmaceutical Sciences – Microbiology, University of Perugia, Perugia, Italy
| | - Mariana Tristezza
- Institute of Sciences of Food Production (ISPA), National Research Council (CNR), Lecce, Italy
| | - Laura Corte
- Department of Pharmaceutical Sciences – Microbiology, University of Perugia, Perugia, Italy
| | - Claudia Colabella
- Department of Pharmaceutical Sciences – Microbiology, University of Perugia, Perugia, Italy
| | - Carla Perrotta
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Lecce, Italy
| | - Patrizia Rampino
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Lecce, Italy
| | - Vincent Robert
- Bioinformatics Unit, Westerdijk Fungal Biodiversity Institute, Utrecht, Netherlands
| | - Duong Vu
- Bioinformatics Unit, Westerdijk Fungal Biodiversity Institute, Utrecht, Netherlands
| | - Gianluigi Cardinali
- Department of Pharmaceutical Sciences – Microbiology, University of Perugia, Perugia, Italy
- Centre of Excellence on Nanostructured Innovative Materials (CEMIN), Department of Chemistry Biology and Biotechnology, University of Perugia, Perugia, Italy
| | - Francesco Grieco
- Institute of Sciences of Food Production (ISPA), National Research Council (CNR), Lecce, Italy
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Colabella C, Corte L, Roscini L, Bassetti M, Tascini C, Mellor JC, Meyer W, Robert V, Vu D, Cardinali G. NGS barcode sequencing in taxonomy and diagnostics, an application in " Candida" pathogenic yeasts with a metagenomic perspective. IMA Fungus 2018; 9:91-105. [PMID: 30018874 PMCID: PMC6048569 DOI: 10.5598/imafungus.2018.09.01.07] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Accepted: 05/10/2018] [Indexed: 11/29/2022] Open
Abstract
Species identification of yeasts and other Fungi is currently carried out with Sanger sequences of selected molecular markers, mainly from the ribosomal DNA operon, characterized by hundreds of tandem repeats of the 18S, ITS1, 5.8S, ITS2 and LSU loci. The ITS region has been recently proposed as a primary barcode marker making this region the most used one in taxonomy, phylogeny and diagnostics. The introduction of NGS is providing tools of high efficacy and relatively low cost to amplify two or more markers simultaneously with great sequencing depth. However, the presence of intra-genomic variability between the repeats requires specific analytical procedures and pipelines. In this study, 286 strains belonging to 11 pathogenic yeasts species were analysed with NGS of the region spanning from ITS1 to the D1/D2 domain of the LSU encoding ribosomal DNA. Results showed that relatively high heterogeneity can hamper the use of these sequences for the identification of single strains and even more of complex microbial mixtures. These observations point out that the metagenomics studies could be affected by species inflection at levels higher than currently expected.
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Affiliation(s)
- Claudia Colabella
- Microbiology Section, Department of Pharmaceutical Sciences, University of Perugia, 06121, Italy
| | - Laura Corte
- Microbiology Section, Department of Pharmaceutical Sciences, University of Perugia, 06121, Italy
| | - Luca Roscini
- Microbiology Section, Department of Pharmaceutical Sciences, University of Perugia, 06121, Italy
| | - Matteo Bassetti
- Infectious Diseases Division, Santa Maria Misericordia University Hospital, Udine, 33100, Italy
| | - Carlo Tascini
- Infectious Diseases Division, Cotugno Hospital Napoli, 80131, Italy
| | | | - Wieland Meyer
- Molecular Mycology Research Laboratory, Centre for Infectious Diseases and Microbiology, Sydney Medical School, Westmead Hospital, Marie Bashir Institute for Infectious Diseases and Biosecurity, The University of Sydney, Westmead Institute for Medical Research, Sydney, NSW 2006, Australia
| | - Vincent Robert
- Bioinformatics Unit, Westerdijk Fungal Biodiversity Institute, 3508 CT, Utrecht, Netherlands
| | - Duong Vu
- Bioinformatics Unit, Westerdijk Fungal Biodiversity Institute, 3508 CT, Utrecht, Netherlands
| | - Gianluigi Cardinali
- Microbiology Section, Department of Pharmaceutical Sciences, University of Perugia, 06121, Italy.,CEMIN Research Centre of Excellence, University of Perugia, Borgo 20 Giugno 74, 06121, Italy
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New Ceratocystis species associated with rapid death of Metrosideros polymorpha in Hawai'i. Persoonia - Molecular Phylogeny and Evolution of Fungi 2018; 40:154-181. [PMID: 30505000 PMCID: PMC6146641 DOI: 10.3767/persoonia.2018.40.07] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 02/10/2018] [Indexed: 12/02/2022]
Abstract
The native ‘ōhi’a lehua (Metrosideros polymorpha) has cultural, biological and ecological significance to Hawai’i, but it is seriously threatened by a disease commonly referred to as rapid ‘ōhi’a death (ROD). Preliminary investigations showed that a Ceratocystis species similar to C. fimbriata s.lat. was the cause of the disease. In this study, we used a combination of the phylogenetic, morphological and biological species concepts, as well as pathogenicity tests and microsatellite analyses, to characterise isolates collected from diseased ‘ōhi’a trees across Hawai’i Island. Two distinct lineages, representing new species of Ceratocystis, were evident based on multigene phylogenetic analyses. These are described here as C. lukuohia and C. huliohia. Ceratocystis lukuohia forms part of the Latin American clade (LAC) and was most closely associated with isolates from Syngonium and Xanthosoma from the Caribbean and elsewhere, including Hawai’i, and C. platani, which is native to eastern USA. Ceratocystis huliohia resides in the Asian-Australian clade (AAC) and is most closely related to C. uchidae, C. changhui and C. cercfabiensis, which are thought to be native to Asia. Morphology and interfertility tests support the delineation of these two new species and pathogenicity tests show that both species are aggressive pathogens on seedlings of M. polymorpha. Characterisation of isolates using microsatellite markers suggest that both species are clonal and likely represent recently-introduced strains. Intensive research is underway to develop rapid screening protocols for early detection of the pathogens and management strategies in an attempt to prevent the spread of the pathogens to the other islands of Hawai’i, which are currently disease free.
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30
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Gong L, Shi W, Yang M, Kong X. Marked intra-genomic variation and pseudogenes in the ITS1-5.8S-ITS2 rDNA of Symphurus plagiusa (Pleuronectiformes: Cynoglossidae). ANIM BIOL 2018. [DOI: 10.1163/15707563-17000134] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Abstract
The eukaryotic ribosomal DNA (rDNA) cluster consists of multiple copies of three genes (18S, 5.8S, and 28S rDNA) and two internal transcribed spacers (ITS1 and ITS2). In recent years, an increasing number of rDNA sequence polymorphisms have been identified in numerous species. In the present study, we provide 33 complete ITS (ITS1-5.8S-ITS2) sequences from two Symphurus plagiusa individuals. To the best of our knowledge, these sequences are the first detailed information on ITS sequences in Pleuronectiformes. Here, two divergent types (Type A and B) of the ITS1-5.8S-ITS2 rDNA sequence were found, which mainly differ in sequence length, GC content, nucleotide diversity (π), secondary structure and minimum free energy. The ITS1-5.8S-ITS2 rDNA sequence of Type B was speculated to be a putative pseudogene according to pseudogene identification criteria. Cluster analysis showed that sequences from the same type clustered into one group and two major groups were formed. The high degree of ITS1-5.8S-ITS2 sequence polymorphism at the intra-specific level indicated that the S. plagiusa genome has evolved in a non-concerted evolutionary manner. These results not only provide useful data for ribosomal pseudogene identification, but also further contribute to the study of rDNA evolution in teleostean genomes.
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Affiliation(s)
- Li Gong
- 1National Engineering Laboratory of Marine Germplasm Resources Exploration and Utilization, Zhejiang Ocean University, 316022, Zhoushan, China
- 2National Engineering Research Center for Facilitated Marine Aquaculture, Marine Science and Technology College, Zhejiang Ocean University, 316022, Zhoushan, China
| | - Wei Shi
- 3Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 510000, Guangzhou, China
- 4South China Sea Bio-Resource Exploitation and Utilization Collaborative Innovation Center, 510000, Guangzhou, China
| | - Min Yang
- 3Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 510000, Guangzhou, China
- 4South China Sea Bio-Resource Exploitation and Utilization Collaborative Innovation Center, 510000, Guangzhou, China
| | - Xiaoyu Kong
- 3Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 510000, Guangzhou, China
- 4South China Sea Bio-Resource Exploitation and Utilization Collaborative Innovation Center, 510000, Guangzhou, China
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31
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SMORE: Synteny Modulator of Repetitive Elements. Life (Basel) 2017; 7:life7040042. [PMID: 29088079 PMCID: PMC5745555 DOI: 10.3390/life7040042] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 10/27/2017] [Accepted: 10/28/2017] [Indexed: 12/19/2022] Open
Abstract
Several families of multicopy genes, such as transfer ribonucleic acids (tRNAs) and ribosomal RNAs (rRNAs), are subject to concerted evolution, an effect that keeps sequences of paralogous genes effectively identical. Under these circumstances, it is impossible to distinguish orthologs from paralogs on the basis of sequence similarity alone. Synteny, the preservation of relative genomic locations, however, also remains informative for the disambiguation of evolutionary relationships in this situation. In this contribution, we describe an automatic pipeline for the evolutionary analysis of such cases that use genome-wide alignments as a starting point to assign orthology relationships determined by synteny. The evolution of tRNAs in primates as well as the history of the Y RNA family in vertebrates and nematodes are used to showcase the method. The pipeline is freely available.
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Dyomin A, Volodkina V, Koshel E, Galkina S, Saifitdinova A, Gaginskaya E. Evolution of ribosomal internal transcribed spacers in Deuterostomia. Mol Phylogenet Evol 2017; 116:87-96. [PMID: 28860009 DOI: 10.1016/j.ympev.2017.08.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 08/11/2017] [Accepted: 08/25/2017] [Indexed: 11/30/2022]
Abstract
Sequences of ribosomal internal transcribed spacers (ITSs) are of great importance to molecular phylogenetics and DNA barcoding, but remain unstudied in some large taxa of Deuterostomia. We have analyzed complete ITS1 and ITS2 sequences in 62 species from 16 Deuterostomia classes, with ITS sequences in 24 species from 11 classes initially obtained using unannotated contigs and raw read sequences. A general tendency for both ITS length and GC-content increase from interior to superior Deuterostomia taxa, a uniform GC-content in both ITSs within the same species, thymine content decrease in sense DNA sequences of both ITSs are shown. A possible role of GC-based gene conversion in Deuterostomia ITS evolutionary changes is hypothesized. The first example of non-LTR retrotransposon insertion into ITS sequence in Deuterostomia is described in turtle Geochelone nigra. The roles of mobile genetic element insertions in the evolution of ITS sequences in some Sauropsida taxa are discussed as well.
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Affiliation(s)
- Alexander Dyomin
- Biological Faculty of Saint-Petersburg State University, Universitetskaya emb. 7/9, Saint-Petersburg 199034, Russia.
| | - Valeria Volodkina
- Biological Faculty of Saint-Petersburg State University, Universitetskaya emb. 7/9, Saint-Petersburg 199034, Russia.
| | - Elena Koshel
- Biological Faculty of Saint-Petersburg State University, Universitetskaya emb. 7/9, Saint-Petersburg 199034, Russia.
| | - Svetlana Galkina
- Biological Faculty of Saint-Petersburg State University, Universitetskaya emb. 7/9, Saint-Petersburg 199034, Russia.
| | - Alsu Saifitdinova
- Biological Faculty of Saint-Petersburg State University, Universitetskaya emb. 7/9, Saint-Petersburg 199034, Russia.
| | - Elena Gaginskaya
- Biological Faculty of Saint-Petersburg State University, Universitetskaya emb. 7/9, Saint-Petersburg 199034, Russia.
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Evolutionary and polymorphism analyses reveal the central role of BTN3A2 in the concerted evolution of the BTN3 gene family. Immunogenetics 2017; 69:379-390. [PMID: 28382515 DOI: 10.1007/s00251-017-0980-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 03/22/2017] [Indexed: 12/11/2022]
Abstract
The butyrophilin 3 (BTN3) receptors are implicated in the T lymphocytes regulation and present a wide plasticity in mammals. In order to understand how these genes have been diversified, we studied their evolution and show that the three human BTN3 are the result of two successive duplications in Primates and that the three genes are present in Hominoids and the Old World Monkey groups. A thorough phylogenetic analysis reveals a concerted evolution of BTN3 characterized by a strong and recurrent homogenization of the region encoding the signal peptide and the immunoglobulin variable (IgV) domain in Hominoids, where the sequences of BTN3A1 or BTN3A3 are replaced by BTN3A2 sequence. In human, the analysis of the diversity of these genes in 1683 individuals representing 26 worldwide populations shows that the three genes are polymorphic, with more than 46 alleles for each gene, and marked by extreme homogenization of the IgV sequences. The same analysis performed for the BTN2 genes shows also a concerted evolution; however, it is not as strong and recurrent as for BTN3. This study shows that BTN3 receptors are marked by extreme concerted evolution at the IgV domain and that BTN3A2 plays a central role in this evolution.
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34
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Marin-Felix Y, Groenewald J, Cai L, Chen Q, Marincowitz S, Barnes I, Bensch K, Braun U, Camporesi E, Damm U, de Beer Z, Dissanayake A, Edwards J, Giraldo A, Hernández-Restrepo M, Hyde K, Jayawardena R, Lombard L, Luangsa-ard J, McTaggart A, Rossman A, Sandoval-Denis M, Shen M, Shivas R, Tan Y, van der Linde E, Wingfield M, Wood A, Zhang J, Zhang Y, Crous P. Genera of phytopathogenic fungi: GOPHY 1. Stud Mycol 2017; 86:99-216. [PMID: 28663602 PMCID: PMC5486355 DOI: 10.1016/j.simyco.2017.04.002] [Citation(s) in RCA: 186] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Genera of Phytopathogenic Fungi (GOPHY) is introduced as a new series of publications in order to provide a stable platform for the taxonomy of phytopathogenic fungi. This first paper focuses on 21 genera of phytopathogenic fungi: Bipolaris, Boeremia, Calonectria, Ceratocystis, Cladosporium, Colletotrichum, Coniella, Curvularia, Monilinia, Neofabraea, Neofusicoccum, Pilidium, Pleiochaeta, Plenodomus, Protostegia, Pseudopyricularia, Puccinia, Saccharata, Thyrostroma, Venturia and Wilsonomyces. For each genus, a morphological description and information about its pathology, distribution, hosts and disease symptoms are provided. In addition, this information is linked to primary and secondary DNA barcodes of the presently accepted species, and relevant literature. Moreover, several novelties are introduced, i.e. new genera, species and combinations, and neo-, lecto- and epitypes designated to provide a stable taxonomy. This first paper includes one new genus, 26 new species, ten new combinations, and four typifications of older names.
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Affiliation(s)
- Y. Marin-Felix
- Westerdijk Fungal Biodiversity Institute, P.O. Box 85167, 3508 AD Utrecht, The Netherlands
- Department of Microbiology and Plant Pathology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, South Africa
| | - J.Z. Groenewald
- Westerdijk Fungal Biodiversity Institute, P.O. Box 85167, 3508 AD Utrecht, The Netherlands
| | - L. Cai
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Q. Chen
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China
| | - S. Marincowitz
- Department of Microbiology and Plant Pathology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, South Africa
| | - I. Barnes
- Department of Genetics, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, South Africa
| | - K. Bensch
- Westerdijk Fungal Biodiversity Institute, P.O. Box 85167, 3508 AD Utrecht, The Netherlands
- Botanische Staatssammlung München, Menzinger Straße 67, D-80638 München, Germany
| | - U. Braun
- Martin-Luther-Universität, Institut für Biologie, Bereich Geobotanik und Botanischer Garten, Herbarium, Neuwerk 21, D-06099 Halle (Saale), Germany
| | - E. Camporesi
- A.M.B. Gruppo Micologico Forlivese “Antonio Cicognani”, Via Roma 18, Forlì, Italy
- A.M.B. Circolo Micologico “Giovanni Carini”, C.P. 314, Brescia, Italy
- Società per gli Studi Naturalistici della Romagna, C.P. 144, Bagnacavallo (RA), Italy
| | - U. Damm
- Senckenberg Museum of Natural History Görlitz, PF 300 154, 02806 Görlitz, Germany
| | - Z.W. de Beer
- Department of Microbiology and Plant Pathology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, South Africa
| | - A. Dissanayake
- Center of Excellence in Fungal Research, School of Science, Mae Fah Luang University, Chiang Rai 57100, Thailand
- Institute of Plant and Environment Protection, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, PR China
| | - J. Edwards
- AgriBio Centre for AgriBiosciences, Department of Economic Development, Jobs, Transport and Resources, 5 Ring Road, LaTrobe University, Bundoora, Victoria 3083, Australia
| | - A. Giraldo
- Westerdijk Fungal Biodiversity Institute, P.O. Box 85167, 3508 AD Utrecht, The Netherlands
- Department of Microbiology and Plant Pathology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, South Africa
| | - M. Hernández-Restrepo
- Westerdijk Fungal Biodiversity Institute, P.O. Box 85167, 3508 AD Utrecht, The Netherlands
- Department of Microbiology and Plant Pathology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, South Africa
| | - K.D. Hyde
- Center of Excellence in Fungal Research, School of Science, Mae Fah Luang University, Chiang Rai 57100, Thailand
- School of Science, Mae Fah Luang University, Chiang Rai 57100, Thailand
| | - R.S. Jayawardena
- Center of Excellence in Fungal Research, School of Science, Mae Fah Luang University, Chiang Rai 57100, Thailand
- Institute of Plant and Environment Protection, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, PR China
| | - L. Lombard
- Westerdijk Fungal Biodiversity Institute, P.O. Box 85167, 3508 AD Utrecht, The Netherlands
| | - J. Luangsa-ard
- Microbe Interaction and Ecology Laboratory, Biodiversity and Biotechnological Resource Research Unit (BBR), BIOTEC, NSTDA 113 Thailand Science Park Phahonyothin Rd., Khlong Nueng, Khlong Luang, Pathum Thani 12120, Thailand
| | - A.R. McTaggart
- Department of Plant and Soil Science, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, South Africa
| | - A.Y. Rossman
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR 97331, USA
| | - M. Sandoval-Denis
- Westerdijk Fungal Biodiversity Institute, P.O. Box 85167, 3508 AD Utrecht, The Netherlands
- Faculty of Natural and Agricultural Sciences, Department of Plant Sciences, University of the Free State, P.O. Box 339, Bloemfontein 9300, South Africa
| | - M. Shen
- Institute of Microbiology, P.O. Box 61, Beijing Forestry University, Beijing 100083, PR China
| | - R.G. Shivas
- Centre for Crop Health, Institute for Agriculture and the Environment, University of Southern Queensland, Toowoomba 4350, Queensland, Australia
| | - Y.P. Tan
- Department of Agriculture & Fisheries, Biosecurity Queensland, Ecosciences Precinct, Dutton Park, Queensland 4102, Australia
- Microbiology, Department of Biology, Utrecht University, Padualaan 8, 3584 CT Utrecht, The Netherlands
| | - E.J. van der Linde
- ARC – Plant Protection Research Institute, Biosystematics Division – Mycology, P. Bag X134, Queenswood 0121, South Africa
| | - M.J. Wingfield
- Department of Microbiology and Plant Pathology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, South Africa
| | - A.R. Wood
- ARC – Plant Protection Research Institute, P. Bag X5017, Stellenbosch 7599, South Africa
| | - J.Q. Zhang
- Institute of Microbiology, P.O. Box 61, Beijing Forestry University, Beijing 100083, PR China
| | - Y. Zhang
- Institute of Microbiology, P.O. Box 61, Beijing Forestry University, Beijing 100083, PR China
| | - P.W. Crous
- Westerdijk Fungal Biodiversity Institute, P.O. Box 85167, 3508 AD Utrecht, The Netherlands
- Department of Microbiology and Plant Pathology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, South Africa
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Sabia L, Di Capua I, Percopo I, Uttieri M, Amato A. ITS2 in calanoid copepods: reconstructing phylogenetic relationships and identifying a newly introduced species in the Mediterranean. EUROPEAN ZOOLOGICAL JOURNAL 2017. [DOI: 10.1080/11250003.2016.1276639] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- L. Sabia
- Department of Science and Technology, University of Naples “Parthenope”, Italy
| | - I. Di Capua
- Department of Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, Italy
| | - I. Percopo
- Department of Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, Italy
| | - M. Uttieri
- Department of Science and Technology, University of Naples “Parthenope”, Italy
- Department of Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, Italy
- CoNISMa, Rome, Italy
| | - A. Amato
- Department of Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, Italy
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DNA Barcoding for Diagnosis and Monitoring of Fungal Plant Pathogens. Fungal Biol 2017. [DOI: 10.1007/978-3-319-34106-4_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Zhang W, Yang S, Zhao H, Huang L. Using the ITS2 sequence-structure as a DNA mini-barcode: A case study in authenticating the traditional medicine“Fang Feng”. BIOCHEM SYST ECOL 2016. [DOI: 10.1016/j.bse.2016.10.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Hawksworthiomyces gen. nov. (Ophiostomatales), illustrates the urgency for a decision on how to name novel taxa known only from environmental nucleic acid sequences (ENAS). Fungal Biol 2016; 120:1323-1340. [DOI: 10.1016/j.funbio.2016.07.004] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Revised: 07/02/2016] [Accepted: 07/12/2016] [Indexed: 11/23/2022]
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Velandia-Huerto CA, Berkemer SJ, Hoffmann A, Retzlaff N, Romero Marroquín LC, Hernández-Rosales M, Stadler PF, Bermúdez-Santana CI. Orthologs, turn-over, and remolding of tRNAs in primates and fruit flies. BMC Genomics 2016; 17:617. [PMID: 27515907 PMCID: PMC4981973 DOI: 10.1186/s12864-016-2927-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 07/11/2016] [Indexed: 12/26/2022] Open
Abstract
Background Transfer RNAs (tRNAs) are ubiquitous in all living organism. They implement the genetic code so that most genomes contain distinct tRNAs for almost all 61 codons. They behave similar to mobile elements and proliferate in genomes spawning both local and non-local copies. Most tRNA families are therefore typically present as multicopy genes. The members of the individual tRNA families evolve under concerted or rapid birth-death evolution, so that paralogous copies maintain almost identical sequences over long evolutionary time-scales. To a good approximation these are functionally equivalent. Individual tRNA copies thus are evolutionary unstable and easily turn into pseudogenes and disappear. This leads to a rapid turnover of tRNAs and often large differences in the tRNA complements of closely related species. Since tRNA paralogs are not distinguished by sequence, common methods cannot not be used to establish orthology between tRNA genes. Results In this contribution we introduce a general framework to distinguish orthologs and paralogs in gene families that are subject to concerted evolution. It is based on the use of uniquely aligned adjacent sequence elements as anchors to establish syntenic conservation of sequence intervals. In practice, anchors and intervals can be extracted from genome-wide multiple sequence alignments. Syntenic clusters of concertedly evolving genes of different families can then be subdivided by list alignments, leading to usually small clusters of candidate co-orthologs. On the basis of recent advances in phylogenetic combinatorics, these candidate clusters can be further processed by cograph editing to recover their duplication histories. We developed a workflow that can be conceptualized as stepwise refinement of a graph of homologous genes. We apply this analysis strategy with different types of synteny anchors to investigate the evolution of tRNAs in primates and fruit flies. We identified a large number of tRNA remolding events concentrated at the tips of the phylogeny. With one notable exception all phylogenetically old tRNA remoldings do not change the isoacceptor class. Conclusions Gene families evolving under concerted evolution are not amenable to classical phylogenetic analyses since paralogs maintain identical, species-specific sequences, precluding the estimation of correct gene trees from sequence differences. This leaves conservation of syntenic arrangements with respect to “anchor elements” that are not subject to concerted evolution as the only viable source of phylogenetic information. We have demonstrated here that a purely synteny-based analysis of tRNA gene histories is indeed feasible. Although the choice of synteny anchors influences the resolution in particular when tight gene clusters are present, and the quality of sequence alignments, genome assemblies, and genome rearrangements limits the scope of the analysis, largely coherent results can be obtained for tRNAs. In particular, we conclude that a large fraction of the tRNAs are recent copies. This proliferation is compensated by rapid pseudogenization as exemplified by many very recent alloacceptor remoldings. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-2927-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Cristian A Velandia-Huerto
- Biology Department, Universidad Nacional de Colombia, Carrera 45 # 26-85, Edif. Uriel Gutiérrez, Bogotá, D.C, Colombia
| | - Sarah J Berkemer
- Max Planck Institute for Mathematics in the Sciences, Inselstraße 22, Leipzig, D-04103, Germany.,Bioinformatics Group, Department of Computer Science, and Interdisciplinary Center for Bioinformatics, Universität Leipzig, Härtelstraße 16-18D-04107, Leipzig, Germany
| | - Anne Hoffmann
- Bioinformatics Group, Department of Computer Science, and Interdisciplinary Center for Bioinformatics, Universität Leipzig, Härtelstraße 16-18D-04107, Leipzig, Germany
| | - Nancy Retzlaff
- Max Planck Institute for Mathematics in the Sciences, Inselstraße 22, Leipzig, D-04103, Germany.,Bioinformatics Group, Department of Computer Science, and Interdisciplinary Center for Bioinformatics, Universität Leipzig, Härtelstraße 16-18D-04107, Leipzig, Germany
| | - Liliana C Romero Marroquín
- Biology Department, Universidad Nacional de Colombia, Carrera 45 # 26-85, Edif. Uriel Gutiérrez, Bogotá, D.C, Colombia
| | - Maribel Hernández-Rosales
- CONACYT - Instituto de Matemáticas, UNAM Juriquilla, Av. Juriquilla #3001, Santiago de Querétaro, MX-76230, QRO, México
| | - Peter F Stadler
- Max Planck Institute for Mathematics in the Sciences, Inselstraße 22, Leipzig, D-04103, Germany. .,Bioinformatics Group, Department of Computer Science, and Interdisciplinary Center for Bioinformatics, Universität Leipzig, Härtelstraße 16-18D-04107, Leipzig, Germany. .,Fraunhofer Institut for Cell Therapy and Immunology, Perlickstraße 1, Leipzig, D-04103, Germany. .,Department of Theoretical Chemistry, University of Vienna, Währinger Straße 17, Vienna, A-1090, Austria. .,Center for non-coding RNA in Technology and Health, Grønegårdsvej 3, Frederiksberg C, DK-1870, Denmark. .,Santa Fe Institute, 1399 Hyde Park Rd., Santa Fe, NM87501, USA.
| | - Clara I Bermúdez-Santana
- Biology Department, Universidad Nacional de Colombia, Carrera 45 # 26-85, Edif. Uriel Gutiérrez, Bogotá, D.C, Colombia
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Chand Dakal T, Giudici P, Solieri L. Contrasting Patterns of rDNA Homogenization within the Zygosaccharomyces rouxii Species Complex. PLoS One 2016; 11:e0160744. [PMID: 27501051 PMCID: PMC4976873 DOI: 10.1371/journal.pone.0160744] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 07/25/2016] [Indexed: 11/18/2022] Open
Abstract
Arrays of repetitive ribosomal DNA (rDNA) sequences are generally expected to evolve as a coherent family, where repeats within such a family are more similar to each other than to orthologs in related species. The continuous homogenization of repeats within individual genomes is a recombination process termed concerted evolution. Here, we investigated the extent and the direction of concerted evolution in 43 yeast strains of the Zygosaccharomyces rouxii species complex (Z. rouxii, Z. sapae, Z. mellis), by analyzing two portions of the 35S rDNA cistron, namely the D1/D2 domains at the 5’ end of the 26S rRNA gene and the segment including the internal transcribed spacers (ITS) 1 and 2 (ITS regions). We demonstrate that intra-genomic rDNA sequence variation is unusually frequent in this clade and that rDNA arrays in single genomes consist of an intermixing of Z. rouxii, Z. sapae and Z. mellis-like sequences, putatively evolved by reticulate evolutionary events that involved repeated hybridization between lineages. The levels and distribution of sequence polymorphisms vary across rDNA repeats in different individuals, reflecting four patterns of rDNA evolution: I) rDNA repeats that are homogeneous within a genome but are chimeras derived from two parental lineages via recombination: Z. rouxii in the ITS region and Z. sapae in the D1/D2 region; II) intra-genomic rDNA repeats that retain polymorphisms only in ITS regions; III) rDNA repeats that vary only in their D1/D2 domains; IV) heterogeneous rDNA arrays that have both polymorphic ITS and D1/D2 regions. We argue that an ongoing process of homogenization following allodiplodization or incomplete lineage sorting gave rise to divergent evolutionary trajectories in different strains, depending upon temporal, structural and functional constraints. We discuss the consequences of these findings for Zygosaccharomyces species delineation and, more in general, for yeast barcoding.
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Affiliation(s)
- Tikam Chand Dakal
- Department of Life Sciences, University of Modena and Reggio Emilia, Via Amendola 2, 42122, Reggio Emilia, Italy
| | - Paolo Giudici
- Department of Life Sciences, University of Modena and Reggio Emilia, Via Amendola 2, 42122, Reggio Emilia, Italy
| | - Lisa Solieri
- Department of Life Sciences, University of Modena and Reggio Emilia, Via Amendola 2, 42122, Reggio Emilia, Italy
- * E-mail:
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Non-concerted evolution in ribosomal ITS2 sequence in Cynoglossus zanzibarensis (Pleuronectiformes: Cynoglossidae). BIOCHEM SYST ECOL 2016. [DOI: 10.1016/j.bse.2016.04.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Selosse MA, Vincenot L, Öpik M. Data processing can mask biology: towards better reporting of fungal barcoding data? THE NEW PHYTOLOGIST 2016; 210:1159-1164. [PMID: 26818207 DOI: 10.1111/nph.13851] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Affiliation(s)
- Marc-André Selosse
- Institut de Systématique, Évolution, Biodiversité (ISYEB - UMR 7205 - CNRS, MNHN, UPMC, EPHE), Muséum National d'Histoire Naturelle, Sorbonne Universités, 57 rue Cuvier, CP50, 75005, Paris, France
- Department of Plant Taxonomy and Nature Conservation, University of Gdansk, Wita Stwosza 59, 80-308, Gdansk, Poland
| | - Lucie Vincenot
- Ecodiv URA/IRSTEA/EA-1293, Normandie Université, SFR Scale 4116, UFR Sciences & Techniques, Université de Rouen, Mont-Saint-Aignan, 76821, France
| | - Maarja Öpik
- Department of Botany, Institute of Ecology and Earth Sciences, University of Tartu, 40 Lai St., Tartu, 51005, Estonia
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A possible centre of diversity in South East Asia for the tree pathogen, Ceratocystis manginecans. INFECTION GENETICS AND EVOLUTION 2016; 41:73-83. [PMID: 27016374 DOI: 10.1016/j.meegid.2016.03.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Revised: 02/29/2016] [Accepted: 03/11/2016] [Indexed: 11/23/2022]
Abstract
The fungal pathogen, Ceratocystis manginecans, has caused serious canker and wilt disease on Mangifera indica (mango), on legume tree species in Oman and Pakistan and on Acacia spp. in Indonesia. A Ceratocystis species, with similar morphology to C. manginecans, has recently been reported in Vietnam, causing severe disease of Acacia trees. Previous population genetic studies on isolates from M. indica in Oman and Pakistan have shown that the pathogen represents a single clonal haplotype, indicative of an introduced pathogen. The aim of this study was to investigate the genetic diversity and population structure of 160 C. manginecans isolates, from four host-associated populations from Oman, Pakistan, Indonesia and Vietnam. This was done by applying a combination of 14 previously developed microsatellite markers and a new set, designed in this study from two different C. manginecans genomes. Sequence data confirmed that the isolates in Vietnam are the same species as those in Indonesia and were thus identified as C. manginecans. Unlike the populations in Oman and Pakistan, relatively high levels of genetic variation were found for the isolates from Indonesia and Vietnam. The Vietnam population was significantly differentiated from the other populations and isolates from this area had the highest level of genetic diversity thus far encountered for the pathogen.
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Intra-Genomic Internal Transcribed Spacer Region Sequence Heterogeneity and Molecular Diagnosis in Clinical Microbiology. Int J Mol Sci 2015; 16:25067-79. [PMID: 26506340 PMCID: PMC4632790 DOI: 10.3390/ijms161025067] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Revised: 10/05/2015] [Accepted: 10/14/2015] [Indexed: 12/15/2022] Open
Abstract
Internal transcribed spacer region (ITS) sequencing is the most extensively used technology for accurate molecular identification of fungal pathogens in clinical microbiology laboratories. Intra-genomic ITS sequence heterogeneity, which makes fungal identification based on direct sequencing of PCR products difficult, has rarely been reported in pathogenic fungi. During the process of performing ITS sequencing on 71 yeast strains isolated from various clinical specimens, direct sequencing of the PCR products showed ambiguous sequences in six of them. After cloning the PCR products into plasmids for sequencing, interpretable sequencing electropherograms could be obtained. For each of the six isolates, 10-49 clones were selected for sequencing and two to seven intra-genomic ITS copies were detected. The identities of these six isolates were confirmed to be Candida glabrata (n=2), Pichia (Candida) norvegensis (n=2), Candida tropicalis (n=1) and Saccharomyces cerevisiae (n=1). Multiple sequence alignment revealed that one to four intra-genomic ITS polymorphic sites were present in the six isolates, and all these polymorphic sites were located in the ITS1 and/or ITS2 regions. We report and describe the first evidence of intra-genomic ITS sequence heterogeneity in four different pathogenic yeasts, which occurred exclusively in the ITS1 and ITS2 spacer regions for the six isolates in this study.
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Oliveira LSS, Harrington TC, Ferreira MA, Damacena MB, Al-Sadi AM, Al-Mahmooli IHS, Alfenas AC. Species or Genotypes? Reassessment of Four Recently Described Species of the Ceratocystis Wilt Pathogen, Ceratocystis fimbriata, on Mangifera indica. PHYTOPATHOLOGY 2015; 105:1229-1244. [PMID: 25822187 DOI: 10.1094/phyto-03-15-0065-r] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Ceratocystis wilt is among the most important diseases on mango (Mangifera indica) in Brazil, Oman, and Pakistan. The causal agent was originally identified in Brazil as Ceratocystis fimbriata, which is considered by some as a complex of many cryptic species, and four new species on mango trees were distinguished from C. fimbriata based on variation in internal transcribed spacer sequences. In the present study, phylogenetic analyses using DNA sequences of mating type genes, TEF-1α, and β-tubulin failed to identify lineages corresponding to the four new species names. Further, mating experiments found that the mango isolates representing the new species were interfertile with each other and a tester strain from sweet potato (Ipomoea batatas), on which the name C. fimbriata is based, and there was little morphological variation among the mango isolates. Microsatellite markers found substantial differentiation among mango isolates at the regional and population levels, but certain microsatellite genotypes were commonly found in multiple populations, suggesting that these genotypes had been disseminated in infected nursery stock. The most common microsatellite genotypes corresponded to the four recently named species (C. manginecans, C. acaciivora, C. mangicola, and C. mangivora), which are considered synonyms of C. fimbriata. This study points to the potential problems of naming new species based on introduced genotypes of a pathogen, the value of an understanding of natural variation within and among populations, and the importance of phenotype in delimiting species.
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Affiliation(s)
- Leonardo S S Oliveira
- First, fourth, and seventh authors: Departamento de Fitopatologia, Universidade Federal de Viçosa, Viçosa, MG 36570-900, Brazil; second author: Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011; third author: Departamento de Fitopatologia, Universidade Federal de Lavras, Lavras, MG 37200-000, Brazil; and fifth and sixth authors: Department of Crop Sciences, Sultan Qaboos University, P.O. Box 34, AlKhoud 123, Oman
| | - Thomas C Harrington
- First, fourth, and seventh authors: Departamento de Fitopatologia, Universidade Federal de Viçosa, Viçosa, MG 36570-900, Brazil; second author: Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011; third author: Departamento de Fitopatologia, Universidade Federal de Lavras, Lavras, MG 37200-000, Brazil; and fifth and sixth authors: Department of Crop Sciences, Sultan Qaboos University, P.O. Box 34, AlKhoud 123, Oman
| | - Maria A Ferreira
- First, fourth, and seventh authors: Departamento de Fitopatologia, Universidade Federal de Viçosa, Viçosa, MG 36570-900, Brazil; second author: Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011; third author: Departamento de Fitopatologia, Universidade Federal de Lavras, Lavras, MG 37200-000, Brazil; and fifth and sixth authors: Department of Crop Sciences, Sultan Qaboos University, P.O. Box 34, AlKhoud 123, Oman
| | - Michelle B Damacena
- First, fourth, and seventh authors: Departamento de Fitopatologia, Universidade Federal de Viçosa, Viçosa, MG 36570-900, Brazil; second author: Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011; third author: Departamento de Fitopatologia, Universidade Federal de Lavras, Lavras, MG 37200-000, Brazil; and fifth and sixth authors: Department of Crop Sciences, Sultan Qaboos University, P.O. Box 34, AlKhoud 123, Oman
| | - Abdullah M Al-Sadi
- First, fourth, and seventh authors: Departamento de Fitopatologia, Universidade Federal de Viçosa, Viçosa, MG 36570-900, Brazil; second author: Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011; third author: Departamento de Fitopatologia, Universidade Federal de Lavras, Lavras, MG 37200-000, Brazil; and fifth and sixth authors: Department of Crop Sciences, Sultan Qaboos University, P.O. Box 34, AlKhoud 123, Oman
| | - Issa H S Al-Mahmooli
- First, fourth, and seventh authors: Departamento de Fitopatologia, Universidade Federal de Viçosa, Viçosa, MG 36570-900, Brazil; second author: Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011; third author: Departamento de Fitopatologia, Universidade Federal de Lavras, Lavras, MG 37200-000, Brazil; and fifth and sixth authors: Department of Crop Sciences, Sultan Qaboos University, P.O. Box 34, AlKhoud 123, Oman
| | - Acelino C Alfenas
- First, fourth, and seventh authors: Departamento de Fitopatologia, Universidade Federal de Viçosa, Viçosa, MG 36570-900, Brazil; second author: Department of Plant Pathology and Microbiology, Iowa State University, Ames 50011; third author: Departamento de Fitopatologia, Universidade Federal de Lavras, Lavras, MG 37200-000, Brazil; and fifth and sixth authors: Department of Crop Sciences, Sultan Qaboos University, P.O. Box 34, AlKhoud 123, Oman
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New Ceratocystis species from Eucalyptus and Cunninghamia in South China. Antonie van Leeuwenhoek 2015; 107:1451-73. [PMID: 25840908 DOI: 10.1007/s10482-015-0441-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Accepted: 03/26/2015] [Indexed: 12/27/2022]
Abstract
During routine surveys for possible fungal pathogens in the rapidly expanding plantations of Eucalyptus and Cunninghamia lanceolata in China, numerous isolates of unknown species in the genus Ceratocystis (Microascales) were obtained from tree wounds. In this study we identified the Ceratocystis isolates from Eucalyptus and Cunninghamia in the GuangDong, GuangXi, FuJian and HaiNan Provinces of South China based on morphology and through comparisons of DNA sequence data for the ITS, partial β-tubulin and TEF-1α gene regions. Morphological and DNA sequence comparisons revealed two previously unknown species residing in the Indo-Pacific Clade. These are described here as Ceratocystis cercfabiensis sp. nov. and Ceratocystis collisensis sp. nov. Isolates of Ceratocystis cercfabiensis showed intragenomic variation in their ITS sequences and four strains were selected for cloning of the ITS gene region. Twelve ITS haplotypes were obtained from 17 clones selected for sequencing, differing in up to seven base positions and representing two separate phylogenetic groups. This is the first evidence of multiple ITS types in isolates of Ceratocystis residing in the Indo-Pacific Clade. Caution should thus be exercised when using the ITS gene region as a barcoding marker for Ceratocystis species in this clade. This study also represents the first record of a species of Ceratocystis from Cunninghamia.
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Abstract
The genus Ceratocystis was established in 1890 and accommodates many important fungi. These include serious plant pathogens, significant insect symbionts and agents of timber degradation that result in substantial economic losses. Virtually since its type was described from sweet potatoes, the taxonomy of Ceratocystis has been confused and vigorously debated. In recent years, particulary during the last two decades, it has become very obvious that this genus includes a wide diversity of very different fungi. These have been roughly lumped together due to their similar morphological structures that have clearly evolved through convergent evolution linked to an insect-associated ecology. As has been true for many other groups of fungi, the emergence of DNA-based sequence data and associated phylogenetic inferences, have made it possible to robustly support very distinct boundaries defined by morphological characters and ecological differences. In this study, DNA-sequence data for three carefully selected gene regions (60S, LSU, MCM7) were generated for 79 species residing in the aggregate genus Ceratocystis sensu lato and these data were subjected to rigorous phylogenetic analyses. The results made it possible to distinguish seven major groups for which generic names have been chosen and descriptions either provided or emended. The emended genera included Ceratocystis sensu stricto, Chalaropsis, Endoconidiophora, Thielaviopsis, and Ambrosiella, while two new genera, Davidsoniella and Huntiella, were described. In total, 30 new combinations have been made. This major revision of the generic boundaries in the Ceratocystidaceae will simplify future treatments and work with an important group of fungi including distantly related species illogically aggregated under a single name.
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Affiliation(s)
- Z.W. de Beer
- Department of Microbiology and Plant Pathology, University of Pretoria, Pretoria 0002, South Africa
| | - T.A. Duong
- Department of Genetics, Forestry and Agricultural Research Institute (FABI), University of Pretoria, Pretoria 0002, South Africa
| | - I. Barnes
- Department of Genetics, Forestry and Agricultural Research Institute (FABI), University of Pretoria, Pretoria 0002, South Africa
| | - B.D. Wingfield
- Department of Genetics, Forestry and Agricultural Research Institute (FABI), University of Pretoria, Pretoria 0002, South Africa
| | - M.J. Wingfield
- Department of Microbiology and Plant Pathology, University of Pretoria, Pretoria 0002, South Africa
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Hodač L, Scheben AP, Hojsgaard D, Paun O, Hörandl E. ITS polymorphisms shed light on hybrid evolution in apomictic plants: a case study on the Ranunculus auricomus complex. PLoS One 2014; 9:e103003. [PMID: 25062066 PMCID: PMC4111349 DOI: 10.1371/journal.pone.0103003] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Accepted: 06/23/2014] [Indexed: 11/18/2022] Open
Abstract
The reconstruction of reticulate evolutionary histories in plants is still a major methodological challenge. Sequences of the ITS nrDNA are a popular marker to analyze hybrid relationships, but variation of this multicopy spacer region is affected by concerted evolution, high intraindividual polymorphism, and shifts in mode of reproduction. The relevance of changes in secondary structure is still under dispute. We aim to shed light on the extent of polymorphism within and between sexual species and their putative natural as well as synthetic hybrid derivatives in the Ranunculus auricomus complex to test morphology-based hypotheses of hybrid origin and parentage of taxa. We employed direct sequencing of ITS nrDNA from 68 individuals representing three sexuals, their synthetic hybrids and one sympatric natural apomict, as well as cloning of ITS copies in four representative individuals, RNA secondary structure analysis, and landmark geometric morphometric analysis on leaves. Phylogenetic network analyses indicate additivity of parental ITS variants in both synthetic and natural hybrids. The triploid synthetic hybrids are genetically much closer to their maternal progenitors, probably due to ploidy dosage effects, although exhibiting a paternal-like leaf morphology. The natural hybrids are genetically and morphologically closer to the putative paternal progenitor species. Secondary structures of ITS1-5.8S-ITS2 were rather conserved in all taxa. The observed similarities in ITS polymorphisms suggest that the natural apomict R. variabilis is an ancient hybrid of the diploid sexual species R. notabilis and the sexual species R. cassubicifolius. The additivity pattern shared by R. variabilis and the synthetic hybrids supports an evolutionary and biogeographical scenario that R. variabilis originated from ancient hybridization. Concerted evolution of ITS copies in R. variabilis is incomplete, probably due to a shift to asexual reproduction. Under the condition of comprehensive inter- and intraspecific sampling, ITS polymorphisms are powerful for elucidating reticulate evolutionary histories.
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Affiliation(s)
- Ladislav Hodač
- Department of Systematics, Biodiversity and Evolution of Plants (with Herbarium), Georg August University Göttingen, Göttingen, Germany
| | - Armin Patrick Scheben
- Department of Systematics, Biodiversity and Evolution of Plants (with Herbarium), Georg August University Göttingen, Göttingen, Germany
| | - Diego Hojsgaard
- Department of Systematics, Biodiversity and Evolution of Plants (with Herbarium), Georg August University Göttingen, Göttingen, Germany
| | - Ovidiu Paun
- Division of Systematic and Evolutionary Botany, University of Vienna, Vienna, Austria
| | - Elvira Hörandl
- Department of Systematics, Biodiversity and Evolution of Plants (with Herbarium), Georg August University Göttingen, Göttingen, Germany
- * E-mail:
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