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Wilken PM, Lane FA, Steenkamp ET, Wingfield MJ, Wingfield BD. Unidirectional mating-type switching is underpinned by a conserved MAT1 locus architecture. Fungal Genet Biol 2024; 170:103859. [PMID: 38114017 DOI: 10.1016/j.fgb.2023.103859] [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: 10/09/2023] [Revised: 12/11/2023] [Accepted: 12/14/2023] [Indexed: 12/21/2023]
Abstract
Unidirectional mating-type switching is a form of homothallic reproduction known only in a small number of filamentous ascomycetes. Their ascospores can give rise to either self-sterile isolates that require compatible partners for subsequent sexual reproduction, or self-fertile individuals capable of completing this process in isolation. The limited studies previously conducted in these fungi suggest that the differences in mating specificity are determined by the architecture of the MAT1 locus. In self-fertile isolates that have not undergone unidirectional mating-type switching, the locus contains both MAT1-1 and MAT1-2 mating-type genes, typical of primary homothallism. In the self-sterile isolates produced after a switching event, the MAT1-2 genes are lacking from the locus, likely due to a recombination-mediated deletion of the MAT1-2 gene information. To determine whether these arrangements of the MAT1 locus support unidirectional mating-type switching in the Ceratocystidaceae, the largest known fungal assemblage capable of this reproduction strategy, a combination of genetic and genomic approaches were used. The MAT1 locus was annotated in representative species of Ceratocystis, Endoconidiophora, and Davidsoniella. In all cases, MAT1-2 genes interrupted the MAT1-1-1 gene in self-fertile isolates. The MAT1-2 genes were flanked by two copies of a direct repeat that accurately predicted the boundaries of the deletion event that would yield the MAT1 locus of self-sterile isolates. Although the relative position of the MAT1-2 gene region differed among species, it always disrupted the MAT1-1-1 gene and/or its expression in the self-fertile MAT1 locus. Following switching, this gene and/or its expression was restored in the self-sterile arrangement of the locus. This mirrors what has been reported in other species capable of unidirectional mating-type switching, providing the strongest support for a conserved MAT1 locus structure that is associated with this process. This study contributes to our understanding of the evolution of unidirectional mating-type switching.
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Affiliation(s)
- P Markus Wilken
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), Faculty of Natural and Agricultural Sciences, University of Pretoria, Private Bag X20, Pretoria 0028, South Africa.
| | - Frances A Lane
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), Faculty of Natural and Agricultural Sciences, University of Pretoria, Private Bag X20, Pretoria 0028, South Africa
| | - Emma T Steenkamp
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), Faculty of Natural and Agricultural Sciences, 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), Faculty of Natural and Agricultural Sciences, University of Pretoria, Private Bag X20, Pretoria 0028, South Africa
| | - Brenda D Wingfield
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), Faculty of Natural and Agricultural Sciences, University of Pretoria, Private Bag X20, Pretoria 0028, South Africa
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Yao L, Kong Y, Yang W, Tian H, Meng X, Zhao X, Zhang R, Sun G, Rollins JA, Liang X. Two Putative Pheromone Receptors, but Not Their Cognate Pheromones, Regulate Female Fertility in the Atypical Mating Fungus Colletotrichum fructicola. PHYTOPATHOLOGY 2023; 113:1934-1945. [PMID: 37141175 DOI: 10.1094/phyto-11-22-0436-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Colletotrichum fungi are a group of damaging phytopathogens with atypical mating type loci (harboring only MAT1-2-1 but not MAT1-1-1) and complex sexual behaviors. Sex pheromones and their cognate G-protein-coupled receptors are conserved regulators of fungal mating. These genes, however, lose function frequently among Colletotrichum species, indicating a possibility that pheromone signaling is dispensable for Colletotrichum sexual reproduction. We have identified two putative pheromone-receptor pairs (PPG1:PRE2, PPG2:PRE1) in C. fructicola, a species that exhibits plus-to-minus mating type switching and plus-minus-mediated mating line development. Here, we report the generation and characterization of gene-deletion mutants for all four genes in both plus and minus strain backgrounds. Single-gene deletion of pre1 or pre2 had no effect on sexual development, whereas their double deletion caused self-sterility in both the plus and minus strains. Moreover, double deletion of pre1 and pre2 caused female sterility in plus-minus outcrossing. Double deletion of pre1 and pre2, however, did not inhibit perithecial differentiation or plus-minus-mediated enhancement of perithecial differentiation. Contrary to the results with pre1 and pre2, double deletion of ppg1 and ppg2 had no effect on sexual compatibility, development, or fecundity. We concluded that pre1 and pre2 coordinately regulate C. fructicola mating by recognizing novel signal molecule(s) distinct from canonical Ascomycota pheromones. The contrasting importance between pheromone receptors and their cognate pheromones highlights the complicated nature of sex regulation in Colletotrichum fungi.
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Affiliation(s)
- Liqiang Yao
- State Key Laboratory of Crop Stress Biology in Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi Province, China
| | - Yuanyuan Kong
- State Key Laboratory of Crop Stress Biology in Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi Province, China
| | - Wenrui Yang
- State Key Laboratory of Crop Stress Biology in Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi Province, China
| | - Huanhuan Tian
- State Key Laboratory of Crop Stress Biology in Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi Province, China
| | - Xiangchen Meng
- State Key Laboratory of Crop Stress Biology in Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi Province, China
| | - Xuemei Zhao
- State Key Laboratory of Crop Stress Biology in Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi Province, China
| | - Rong Zhang
- State Key Laboratory of Crop Stress Biology in Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi Province, China
| | - Guangyu Sun
- State Key Laboratory of Crop Stress Biology in Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi Province, China
| | - Jeffrey A Rollins
- Department of Plant Pathology, University of Florida, Gainesville, FL, U.S.A
| | - Xiaofei Liang
- State Key Laboratory of Crop Stress Biology in Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi Province, China
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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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Mating-Type Switching in Budding Yeasts, from Flip/Flop Inversion to Cassette Mechanisms. Microbiol Mol Biol Rev 2022; 86:e0000721. [PMID: 35195440 PMCID: PMC8941940 DOI: 10.1128/mmbr.00007-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mating-type switching is a natural but unusual genetic control process that regulates cell identity in ascomycete yeasts. It involves physically replacing one small piece of genomic DNA by another, resulting in replacement of the master regulatory genes in the mating pathway and hence a switch of cell type and mating behavior. In this review, we concentrate on recent progress that has been made on understanding the origins and evolution of mating-type switching systems in budding yeasts (subphylum Saccharomycotina). Because of the unusual nature and the complexity of the mechanism in Saccharomyces cerevisiae, mating-type switching was assumed until recently to have originated only once or twice during yeast evolution. However, comparative genomics analysis now shows that switching mechanisms arose many times independently-at least 11 times in budding yeasts and once in fission yeasts-a dramatic example of convergent evolution. Most of these lineages switch mating types by a flip/flop mechanism that inverts a section of a chromosome and is simpler than the well-characterized 3-locus cassette mechanism (MAT/HML/HMR) used by S. cerevisiae. Mating-type switching (secondary homothallism) is one of the two possible mechanisms by which a yeast species can become self-fertile. The other mechanism (primary homothallism) has also emerged independently in multiple evolutionary lineages of budding yeasts, indicating that homothallism has been favored strongly by natural selection. Recent work shows that HO endonuclease, which makes the double-strand DNA break that initiates switching at the S. cerevisiae MAT locus, evolved from an unusual mobile genetic element that originally targeted a glycolytic gene, FBA1.
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Yu C, Diao Y, Lu Q, Zhao J, Cui S, Xiong X, Lu A, Zhang X, Liu H. Comparative Genomics Reveals Evolutionary Traits, Mating Strategies, and Pathogenicity-Related Genes Variation of Botryosphaeriaceae. Front Microbiol 2022; 13:800981. [PMID: 35283828 PMCID: PMC8905617 DOI: 10.3389/fmicb.2022.800981] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2021] [Accepted: 02/03/2022] [Indexed: 11/13/2022] Open
Abstract
Botryosphaeriaceae, as a major family of the largest class of kingdom fungi Dothideomycetes, encompasses phytopathogens, saprobes, and endophytes. Many members of this family are opportunistic phytopathogens with a wide host range and worldwide geographical distribution, and can infect many economically important plants, including food crops and raw material plants for biofuel production. To date, however, little is known about the family evolutionary characterization, mating strategies, and pathogenicity-related genes variation from a comparative genome perspective. Here, we conducted a large-scale whole-genome comparison of 271 Dothideomycetes, including 19 species in Botryosphaeriaceae. The comparative genome analysis provided a clear classification of Botryosphaeriaceae in Dothideomycetes and indicated that the evolution of lifestyle within Dothideomycetes underwent four major transitions from non-phytopathogenic to phytopathogenic. Mating strategies analysis demonstrated that at least 3 transitions were found within Botryosphaeriaceae from heterothallism to homothallism. Additionally, pathogenicity-related genes contents in different genera varied greatly, indicative of genus-lineage expansion within Botryosphaeriaceae. These findings shed new light on evolutionary traits, mating strategies and pathogenicity-related genes variation of Botryosphaeriaceae.
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Affiliation(s)
- Chengming Yu
- Shandong Research Center for Forestry Harmful Biological Control Engineering and Technology, College of Plant Protection, Shandong Agricultural University, Taian, China
| | - Yufei Diao
- Shandong Research Center for Forestry Harmful Biological Control Engineering and Technology, College of Plant Protection, Shandong Agricultural University, Taian, China
| | - Quan Lu
- Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing, China
| | - Jiaping Zhao
- Institute of Forestry New Technology, Chinese Academy of Forestry, Beijing, China
| | - Shengnan Cui
- Shandong Research Center for Forestry Harmful Biological Control Engineering and Technology, College of Plant Protection, Shandong Agricultural University, Taian, China
| | - Xiong Xiong
- Shandong Research Center for Forestry Harmful Biological Control Engineering and Technology, College of Plant Protection, Shandong Agricultural University, Taian, China
| | - Anna Lu
- Shandong Research Center for Forestry Harmful Biological Control Engineering and Technology, College of Plant Protection, Shandong Agricultural University, Taian, China
| | - Xingyao Zhang
- Institute of Forestry New Technology, Chinese Academy of Forestry, Beijing, China
| | - Huixiang Liu
- Shandong Research Center for Forestry Harmful Biological Control Engineering and Technology, College of Plant Protection, Shandong Agricultural University, Taian, China
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Poli A, Prigione V, Bovio E, Perugini I, Varese GC. Insights on Lulworthiales Inhabiting the Mediterranean Sea and Description of Three Novel Species of the Genus Paralulworthia. J Fungi (Basel) 2021; 7:940. [PMID: 34829227 PMCID: PMC8623521 DOI: 10.3390/jof7110940] [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: 09/08/2021] [Revised: 10/26/2021] [Accepted: 11/03/2021] [Indexed: 11/24/2022] Open
Abstract
The order Lulworthiales, with its sole family Lulworthiaceae, consists of strictly marine genera found on a wide range of substrates such as seagrasses, seaweeds, and seafoam. Twenty-one unidentified Lulworthiales were isolated in previous surveys aimed at broadening our understanding of the biodiversity hosted in the Mediterranean Sea. Here, these organisms, mostly found in association with Posidonia oceanica and with submerged woods, were examined using thorough multi-locus phylogenetic analyses and morphological observations. Maximum-likelihood and Bayesian phylogeny based on nrITS, nrSSU, nrLSU, and four protein-coding genes led to the introduction of three novel species of the genus Paralulworthia: P. candida, P. elbensis, and P. mediterranea. Once again, the marine environment is a confirmed huge reservoir of novel fungal lineages with an under-investigated biotechnological potential waiting to be explored.
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Affiliation(s)
| | - Valeria Prigione
- Mycotheca Universitatis Taurinensis, Department of Life Sciences and Systems Biology, University of Torino, Viale Mattioli 25, 10125 Torino, Italy; (A.P.); (E.B.); (I.P.); (G.C.V.)
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7
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Abstract
Pneumocystis species colonize mammalian lungs and cause deadly pneumonia if the immune system of the host weakens. Each species presents a specificity for a single mammalian host species. Pneumocystis jirovecii infects humans and provokes pneumonia, which is among the most frequent invasive fungal infections. The lack of in vitro culture methods for these fungi complicates their study. Recently, high-throughput sequencing technologies followed by comparative genomics have allowed a better understanding of the mechanisms involved in the sexuality of Pneumocystis organisms. The structure of their mating-type locus corresponding to a fusion of two loci, Plus and Minus, and the concomitant expression of the three mating-type genes revealed that their mode of sexual reproduction is primarily homothallism. This mode is favored by microbial pathogens and involves a single self-compatible mating type that can enter into the sexual cycle on its own. Pneumocystis sexuality is obligatory within the host's lungs during pneumonia in adults, primary infection in children, and possibly colonization. This sexuality participates in cell proliferation, airborne transmission to new hosts, and probably antigenic variation, processes that are crucial to ensure the survival of the fungus. Thus, sexuality is central in the Pneumocystis life cycle. The obligate biotrophic parasitism with obligate sexuality of Pneumocystis is unique among fungi pathogenic to humans. Pneumocystis organisms are similar to the plant fungal obligate biotrophs that complete their entire life cycle within their hosts, including sex, and that are also difficult to grow in vitro.
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Krämer D, Lane FA, Steenkamp ET, Wingfield BD, Wilken PM. Unidirectional mating-type switching confers self-fertility to Thielaviopsis cerberus, the only homothallic species in the genus. Fungal Biol 2021; 125:427-434. [PMID: 34024590 DOI: 10.1016/j.funbio.2020.12.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 12/28/2020] [Accepted: 12/30/2020] [Indexed: 11/29/2022]
Abstract
Sexual reproduction is ubiquitous in nature, and nowhere is this more so than in the fungi. Heterothallic behaviour is observed when there is a strict requirement of contact between two individuals of opposite mating type for sexual reproduction to occur. In contrast, a homothallic species can complete the entire sexual cycle in isolation, although several genetic mechanisms underpin this self-fertility. These can be inferred by characterising the structure and gene-content of the mating-type locus, which contains genes that are involved in the regulation of sexual reproduction. In this study, the genetic basis of homothallism in Thielaviopsis cerberus was investigated, the only known self-fertile species within this genus. Using genome sequencing and conventional molecular techniques, two versions of the mating-type locus were identified in this species. This is typical of species that have a unidirectional mating-type switching reproductive strategy. The first version was a self-fertile locus that contained four known mating-type genes, while the second was a self-sterile version with a single mating-type gene. The conversion from a self-fertile to a self-sterile locus is likely mediated by a homologous recombination event at two direct repeats present in the self-fertile locus, resulting in the deletion of three mating-type genes and one of the repeats. Both locus versions were present in isolates that were self-fertile, while self-sterility was caused by the presence of only a switched locus. This study provides a clear example of the architectural fluidity in the mating-type loci that is common among even closely related fungal species.
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Affiliation(s)
- Daniella Krämer
- Department of Biochemistry, Genetics and Microbiology; Forestry and Agricultural Biotechnology Institute, University of Pretoria, Private Bag X20, Hatfield, Pretoria, 0028, South Africa
| | - Frances A Lane
- Department of Biochemistry, Genetics and Microbiology; Forestry and Agricultural Biotechnology Institute, University of Pretoria, Private Bag X20, Hatfield, Pretoria, 0028, South Africa
| | - Emma T Steenkamp
- Department of Biochemistry, Genetics and Microbiology; Forestry and Agricultural Biotechnology Institute, University of Pretoria, Private Bag X20, Hatfield, Pretoria, 0028, South Africa
| | - Brenda D Wingfield
- Department of Biochemistry, Genetics and Microbiology; Forestry and Agricultural Biotechnology Institute, University of Pretoria, Private Bag X20, Hatfield, Pretoria, 0028, South Africa
| | - P Markus Wilken
- Department of Biochemistry, Genetics and Microbiology; Forestry and Agricultural Biotechnology Institute, University of Pretoria, Private Bag X20, Hatfield, Pretoria, 0028, South Africa. http://
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Nagel JH, Wingfield MJ, Slippers B. Evolution of the mating types and mating strategies in prominent genera in the Botryosphaeriaceae. Fungal Genet Biol 2018. [PMID: 29530630 DOI: 10.1016/j.fgb.2018.03.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Little is known regarding mating strategies in the Botryosphaeriaceae. To understand sexual reproduction in this fungal family, the mating type genes of Botryosphaeria dothidea and Macrophomina phaseolina, as well as several species of Diplodia, Lasiodiplodia and Neofusicoccum were characterized from whole genome assemblies. Comparisons between the mating type loci of these fungi showed that the mating type genes are highly variable, but in most cases the organization of these genes is conserved. Of the species considered, nine were homothallic and seven were heterothallic. Mating type gene fragments were discovered flanking the mating type regions, which indicates both ongoing and ancestral recombination occurring within the mating type region. Ancestral reconstruction analysis further indicated that heterothallism is the ancestral state in the Botryosphaeriaceae and this is supported by the presence of mating type gene fragments in homothallic species. The results also show that at least five transitions from heterothallism to homothallism have taken place in the Botryosphaeriaceae. The study provides a foundation for comparison of mating type evolution between Botryosphaeriaceae and other fungi and also provides valuable markers for population biology studies in this family.
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Affiliation(s)
- Jan H Nagel
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria 0001, South Africa
| | - Michael J Wingfield
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria 0001, South Africa
| | - Bernard Slippers
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria 0001, South Africa.
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Wilken PM, Steenkamp ET, van der Nest MA, Wingfield MJ, de Beer ZW, Wingfield BD. Unexpected placement of the MAT1-1-2 gene in the MAT1-2 idiomorph of Thielaviopsis. Fungal Genet Biol 2018; 113:32-41. [PMID: 29409964 DOI: 10.1016/j.fgb.2018.01.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2017] [Revised: 01/20/2018] [Accepted: 01/29/2018] [Indexed: 01/24/2023]
Abstract
Sexual reproduction in the Ascomycota is controlled by genes encoded at the mating-type or MAT1 locus. The two allelic versions of this locus in heterothallic species, referred to as idiomorphs, are defined by the MAT1-1-1 (for the MAT1-1 idiomorph) and MAT1-2-1 (for the MAT1-2 idiomorph) genes. Both idiomorphs can contain additional genes, although the contents of each is typically specific to and conserved within particular Pezizomycotina lineages. Using full genome sequences, complemented with conventional PCR and Sanger sequencing, we compared the mating-type idiomorphs in heterothallic species of Thielaviopsis (Ceratocystidaceae). The analyses showed that the MAT1-1 idiomorph of T. punctulata, T. paradoxa, T. euricoi, T. ethacetica and T. musarum harboured only the expected MAT1-1-1 gene. In contrast, the MAT1-2 idiomorph of T. punctulata, T. paradoxa and T. euricoi encoded the MAT1-2-1, MAT1-2-7 and MAT1-1-2 genes. Of these, MAT1-2-1 and MAT1-2-7 are genes previously reported in this idiomorph, while MAT1-1-2 is known only in the MAT1-1 idiomorph. Phylogenetic analysis showed that the Thielaviopsis MAT1-1-2 groups with the known homologues of this gene in other Microascales, thus confirming its annotation. Previous work suggests that MAT1-1-2 is involved in fruiting body development, a role that would be unaffected by its idiomorphic position. This notion is supported by our findings for the MAT1 locus structure in Thielaviopsis species. This also serves as the first example of a MAT1-1-specific gene restricted to only the MAT1-2 idiomorph.
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Affiliation(s)
- P Markus Wilken
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), Faculty of Natural and Agricultural Sciences, University of Pretoria, Private Bag X20, Pretoria 0028, South Africa.
| | - Emma T Steenkamp
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), Faculty of Natural and Agricultural Sciences, University of Pretoria, Private Bag X20, Pretoria 0028, South Africa
| | - Magriet A van der Nest
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), Faculty of Natural and Agricultural Sciences, 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), Faculty of Natural and Agricultural Sciences, University of Pretoria, Private Bag X20, Pretoria 0028, South Africa
| | - Z Wilhelm de Beer
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), Faculty of Natural and Agricultural Sciences, University of Pretoria, Private Bag X20, Pretoria 0028, South Africa
| | - Brenda D Wingfield
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), Faculty of Natural and Agricultural Sciences, University of Pretoria, Private Bag X20, Pretoria 0028, South Africa
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