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Holden S, Bakkeren G, Hubensky J, Bamrah R, Abbasi M, Qutob D, de Graaf ML, Kim SH, Kutcher HR, McCallum BD, Randhawa HS, Iqbal M, Uloth K, Burlakoti RR, Brar GS. Uncovering the history of recombination and population structure in western Canadian stripe rust populations through mating type alleles. BMC Biol 2023; 21:233. [PMID: 37880702 PMCID: PMC10601111 DOI: 10.1186/s12915-023-01717-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 09/27/2023] [Indexed: 10/27/2023] Open
Abstract
BACKGROUND The population structure of crop pathogens such as Puccinia striiformis f. sp. tritici (Pst), the cause of wheat stripe rust, is of interest to researchers looking to understand these pathogens on a molecular level as well as those with an applied focus such as disease epidemiology. Cereal rusts can reproduce sexually or asexually, and the emergence of novel lineages has the potential to cause serious epidemics such as the one caused by the 'Warrior' lineage in Europe. In a global context, Pst lineages in Canada were not well-characterized and the origin of foreign incursions was not known. Additionally, while some Pst mating type genes have been identified in published genomes, there has been no rigorous assessment of mating type diversity and distribution across the species. RESULTS We used a whole-genome/transcriptome sequencing approach for the Canadian Pst population to identify lineages in their global context and evidence tracing foreign incursions. More importantly: for the first time ever, we identified nine alleles of the homeodomain mating type locus in the worldwide Pst population and show that previously identified lineages exhibit a single pair of these alleles. Consistently with the literature, we find only two pheromone receptor mating type alleles. We show that the recent population shift from the 'PstS1' lineage to the 'PstS1-related' lineage is also associated with the introduction of a novel mating type allele (Pst-b3-HD) to the Canadian population. We also show evidence for high levels of mating type diversity in samples associated with the Himalayan center of diversity for Pst, including a single Canadian race previously identified as 'PstPr' (probable recombinant) which we identify as a foreign incursion, most closely related to isolates sampled from China circa 2015. CONCLUSIONS These data describe a recent shift in the population of Canadian Pst field isolates and characterize homeodomain-locus mating type alleles in the global Pst population which can now be utilized in testing several research questions and hypotheses around sexuality and hybridization in rust fungi.
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Affiliation(s)
- Samuel Holden
- Faculty of Land and Food Systems, The University of British Columbia (UBC), Vancouver, BC, Canada.
| | - Guus Bakkeren
- Agriculture and Agri-Food Canada (AAFC), Summerland Research and Development Center, Summerland, BC, Canada
| | - John Hubensky
- Faculty of Land and Food Systems, The University of British Columbia (UBC), Vancouver, BC, Canada
| | - Ramandeep Bamrah
- Faculty of Land and Food Systems, The University of British Columbia (UBC), Vancouver, BC, Canada
| | - Mehrdad Abbasi
- Faculty of Land and Food Systems, The University of British Columbia (UBC), Vancouver, BC, Canada
| | - Dinah Qutob
- Kent State University, Stark Campus, North Canton, OH, USA
| | - Mei-Lan de Graaf
- Agriculture and Agri-Food Canada (AAFC), Summerland Research and Development Center, Summerland, BC, Canada
| | - Sang Hu Kim
- Agriculture and Agri-Food Canada (AAFC), Summerland Research and Development Center, Summerland, BC, Canada
| | - Hadley R Kutcher
- Department of Plant Science/Crop Development Centre, University of Saskatchewan, Saskatoon, SK, Canada
| | - Brent D McCallum
- Agriculture and Agri-Food Canada (AAFC), Brandon Research and Development Center, Brandon, MB, Canada
| | - Harpinder S Randhawa
- Agriculture and Agri-Food Canada (AAFC), Lethbridge Research and Development Center, Lethbridge, AB, Canada
| | - Muhammad Iqbal
- Faculty of Agricultural, Life & Environmental Sciences, University of Alberta, Edmonton, AB, Canada
| | - Keith Uloth
- British Columbia Pest Monitoring Network, Dawson Creek, BC, Canada
| | - Rishi R Burlakoti
- Agriculture and Agri-Food Canada (AAFC), Agassiz Research and Development Center, Agassiz, BC, Canada
| | - Gurcharn S Brar
- Faculty of Land and Food Systems, The University of British Columbia (UBC), Vancouver, BC, Canada.
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Chigira Y, Sasaki N, Komatsu K, Mashimo K, Tanaka S, Numamoto M, Moriyama H, Motobayashi T. Mating Types of Ustilago esculenta Infecting Zizania latifolia Cultivars in Japan Are Biased towards MAT-2 and MAT-3. Microbes Environ 2023; 38:ME23034. [PMID: 37704449 PMCID: PMC10522849 DOI: 10.1264/jsme2.me23034] [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: 04/14/2023] [Accepted: 08/01/2023] [Indexed: 09/15/2023] Open
Abstract
Zizania latifolia cultivars infected by the endophytic fungus Ustilago esculenta develop an edible stem gall. Stem gall development varies among cultivars and individuals and may be affected by the strain of U. esculenta. To isolate haploids from two Z. latifolia cultivars in our paddy fields, Shirakawa and Ittenkou, we herein performed the sporadic isolation of U. esculenta strains from stem gall tissue, a PCR-based assessment of the mating type, and in vitro mating experiments. As a result, we obtained heterogametic strains of MAT-2 and MAT-3 as well as MAT-2, but not MAT-3, haploid strains. Another isolation method, in which we examined poorly growing small clusters of sporidia derived from teliospores, succeeded in isolating a MAT-3 haploid strain. We also identified the mating types of 10 U. esculenta strains collected as genetic resources from different areas in Japan. All strains, except for one MAT-1 haploid strain, were classified as MAT-2 haploid strains or heterogametic strains of MAT-2 and MAT-3. The isolated strains of MAT-1, MAT-2, and MAT-3 mated with each other to produce hyphae. Collectively, these results indicate that the mating types of U. esculenta infecting Z. latifolia cultivars in Japan are biased towards MAT-2 and MAT-3 and that U. esculenta populations in these Japanese cultivars may be characterized by the low isolation efficiency of the MAT-3 haploid.
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Affiliation(s)
- Yuka Chigira
- Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183-8509, Japan
| | - Nobumitsu Sasaki
- Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183-8509, Japan
- Gene Research Center, Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183-8509, Japan
- Institute of Global Innovation Research (GIR), Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183-8509, Japan
| | - Ken Komatsu
- Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183-8509, Japan
- Institute of Global Innovation Research (GIR), Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183-8509, Japan
| | - Kouji Mashimo
- Field Science Center, Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183-8509, Japan
| | - Shigeyuki Tanaka
- Faculty of Agriculture, Setsunan University, Hirakata, Osaka 573-0101, Japan
| | - Minori Numamoto
- Faculty of Agriculture, Setsunan University, Hirakata, Osaka 573-0101, Japan
| | - Hiromitsu Moriyama
- Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183-8509, Japan
| | - Takashi Motobayashi
- Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183-8509, Japan
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Agisha VN, Nalayeni K, Ashwin NMR, Vinodhini RT, Jeyalekshmi K, Suraj Kumar M, Ramesh Sundar A, Malathi P, Viswanathan R. Molecular Discrimination of Opposite Mating Type Haploids of Sporisorium scitamineum and Establishing Their Dimorphic Transitions During Interaction with Sugarcane. SUGAR TECH 2022. [DOI: https:/doi.org/10.1007/s12355-021-01085-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/09/2023]
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4
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Agisha VN, Nalayeni K, Ashwin NMR, Vinodhini RT, Jeyalekshmi K, Suraj Kumar M, Ramesh Sundar A, Malathi P, Viswanathan R. Molecular Discrimination of Opposite Mating Type Haploids of Sporisorium scitamineum and Establishing Their Dimorphic Transitions During Interaction with Sugarcane. SUGAR TECH 2022. [DOI: 10.1007/s12355-021-01085-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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5
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Kwon S, Rupp O, Brachmann A, Blum CF, Kraege A, Goesmann A, Feldbrügge M. mRNA Inventory of Extracellular Vesicles from Ustilago maydis. J Fungi (Basel) 2021; 7:jof7070562. [PMID: 34356940 PMCID: PMC8306574 DOI: 10.3390/jof7070562] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 07/02/2021] [Accepted: 07/07/2021] [Indexed: 01/08/2023] Open
Abstract
Extracellular vesicles (EVs) can transfer diverse RNA cargo for intercellular communication. EV-associated RNAs have been found in diverse fungi and were proposed to be relevant for pathogenesis in animal hosts. In plant-pathogen interactions, small RNAs are exchanged in a cross-kingdom RNAi warfare and EVs were considered to be a delivery mechanism. To extend the search for EV-associated molecules involved in plant-pathogen communication, we have characterised the repertoire of EV-associated mRNAs secreted by the maize smut pathogen, Ustilago maydis. For this initial survey, we examined EV-enriched fractions from axenic filamentous cultures that mimic infectious hyphae. EV-associated RNAs were resistant to degradation by RNases and the presence of intact mRNAs was evident. The set of mRNAs enriched inside EVs relative to the fungal cells are functionally distinct from those that are depleted from EVs. mRNAs encoding metabolic enzymes are particularly enriched. Intriguingly, mRNAs of some known effectors and other proteins linked to virulence were also found in EVs. Furthermore, several mRNAs enriched in EVs are also upregulated during infection, suggesting that EV-associated mRNAs may participate in plant-pathogen interactions.
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Affiliation(s)
- Seomun Kwon
- Institute for Microbiology, Cluster of Excellence on Plant Sciences, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (S.K.); (A.K.)
| | - Oliver Rupp
- Bioinformatics and Systems Biology, Justus-Liebig-Universität, 35392 Giessen, Germany; (O.R.); (A.G.)
| | - Andreas Brachmann
- Biocenter of the LMU Munich, Genetics Section, Grosshaderner Str. 2-4, 82152 Planegg-Martinsried, Germany;
| | - Christopher Frederik Blum
- Institute for Mathematical Modelling of Biological Systems, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany;
| | - Anton Kraege
- Institute for Microbiology, Cluster of Excellence on Plant Sciences, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (S.K.); (A.K.)
| | - Alexander Goesmann
- Bioinformatics and Systems Biology, Justus-Liebig-Universität, 35392 Giessen, Germany; (O.R.); (A.G.)
| | - Michael Feldbrügge
- Institute for Microbiology, Cluster of Excellence on Plant Sciences, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany; (S.K.); (A.K.)
- Correspondence: ; Tel.: +49-211-81-14720
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Kämper J, Friedrich MW, Kahmann R. Creating novel specificities in a fungal nonself recognition system by single step homologous recombination events. THE NEW PHYTOLOGIST 2020; 228:1001-1010. [PMID: 32559311 DOI: 10.1111/nph.16755] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 05/05/2020] [Indexed: 06/11/2023]
Abstract
In many organisms, two component systems have evolved to discriminate self from nonself. While the molecular function of the two components has been elucidated in several systems, the evolutionary events leading to the large number of different specificities for self-nonself recognition found in most systems remain obscure. We have investigated the variation within a multiallelic nonself recognition system in the phytopathogenic basidiomycete Ustilago maydis by means of sequence analysis and functional studies. The multiallelic b mating type locus of U. maydis ensures outbreeding during sexual development. Nonself recognition is specified by the two homeodomain proteins, bE and bW, encoded by the b locus. While bE-bW combinations from the same allele do not dimerize, bE and bW proteins originating from different alleles form a heterodimeric complex that functions as master regulator for sexual and pathogenic development. We show that novel specificities of the b mating type locus have arisen by single homologous recombination events between distinct b alleles that lead to a simultaneous exchange of subdomains involved in dimerization in both bE and bW, altering the specificity of both proteins in a single step.
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Affiliation(s)
- Jörg Kämper
- Department Organismic Interactions, Max Planck Institute for Terrestrial Microbiology, Karl-von-Frisch-Strasse 10, Marburg, 35043, Germany
- Department of Genetics, Institute for Applied Biosciences, Karlsruhe Institute of Technology, Fritz Haber Weg 4, Karlsruhe, 76131, Germany
| | - Michael W Friedrich
- Department Organismic Interactions, Max Planck Institute for Terrestrial Microbiology, Karl-von-Frisch-Strasse 10, Marburg, 35043, Germany
- Microbial Ecophysiology Group BreMarE, University of Bremen, Leobener Straße 3, Bremen, 28359, Germany
| | - Regine Kahmann
- Department Organismic Interactions, Max Planck Institute for Terrestrial Microbiology, Karl-von-Frisch-Strasse 10, Marburg, 35043, Germany
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Zhao S, An B, Guo Y, Hou X, Luo H, He C, Wang Q. Label free proteomics and systematic analysis of secretome reveals effector candidates regulated by SGE1 and FTF1 in the plant pathogen Fusarium oxysporum f. sp. cubense tropical race 4. BMC Genomics 2020; 21:275. [PMID: 32245409 PMCID: PMC7119298 DOI: 10.1186/s12864-020-6695-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 03/24/2020] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Phytopathogens secreted effectors during host colonization to suppress or trigger plant immunity. Identification of new effectors is one of the research focuses in recent years. There is only a limited knowledge about effectors of Fusarium oxysporum f. sp. Cubense tropical race 4 (Foc TR4), the causal agent of wilt disease in Cavendish banana. RESULTS Two transcription factors, SGE1 and FTF1, were constitutively over-expressed in Foc TR4 to partially mimic the in-planta state. Secreted proteins with high purity were prepared through a two-round extraction method. Then the secretome were analyzed via label free proteomics method. A total of 919 non-redundant proteins were detected, of which 74 proteins were predicted to be effector candidates. Among these candidates, 29 were up-regulated and 13 down-regulated in the strain over-expressing SGE1 and FTF1, 8 were up-regulated and 4 down-regulated in either SGE1 or FTF1 over expression strain. CONCLUSIONS Through label free proteomics analysis, a series of effector candidates were identified in secretome of Foc TR4. Our work put a foundation for functional research of these effectors.
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Affiliation(s)
- Shixue Zhao
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, College of Tropical Crops, Hainan University, Haikou, Hainan, 570228, People's Republic of China
| | - Bang An
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, College of Tropical Crops, Hainan University, Haikou, Hainan, 570228, People's Republic of China
| | - Yanhua Guo
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, College of Tropical Crops, Hainan University, Haikou, Hainan, 570228, People's Republic of China
| | - Xingrong Hou
- College of Fisheries and Life Science, Hainan Tropical Ocean University, Sanya, Hainan, 572022, People's Republic of China
| | - Hongli Luo
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, College of Tropical Crops, Hainan University, Haikou, Hainan, 570228, People's Republic of China
| | - Chaozu He
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, College of Tropical Crops, Hainan University, Haikou, Hainan, 570228, People's Republic of China
| | - Qiannan Wang
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, College of Tropical Crops, Hainan University, Haikou, Hainan, 570228, People's Republic of China.
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8
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Gene expression in the smut fungus Ustilago esculenta governs swollen gall metamorphosis in Zizania latifolia. Microb Pathog 2020; 143:104107. [PMID: 32120003 DOI: 10.1016/j.micpath.2020.104107] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 02/23/2020] [Accepted: 02/25/2020] [Indexed: 01/02/2023]
Abstract
Ustilago esculenta, a smut fungus, can induce the formation of culm galls in Zizania latifolia, a vegetable consumed in many Asian countries. Specifically, the mycelia-teliospore (M-T) strain of U. esculenta induces the Jiaobai (JB) type of gall, while the teliospore (T) strain induces the Huijiao (HJ) type. The underlying molecular mechanism responsible for the formation of the two distinct types of gall remains unclear. Our results showed that most differentially expressed genes relevant to effector proteins were up-regulated in the T strain compared to those in the M-T strain during gall formation, and the expression of teliospore formation-related genes was higher in the T strain than the M-T strain. Melanin biosynthesis was also clearly induced in the T strain. The T strain exhibited stronger pathogenicity and greater teliospore production than the M-T strain. We evaluated the implications of the gene regulatory networks in the development of these two type of culm gall in Z. latifolia infected with U. esculenta and suggested potential targets for genetic manipulation to modify the gall type for this crop.
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Schmitz L, Kronstad JW, Heimel K. Conditional gene expression reveals stage-specific functions of the unfolded protein response in the Ustilago maydis-maize pathosystem. MOLECULAR PLANT PATHOLOGY 2020; 21:258-271. [PMID: 31802604 PMCID: PMC6988420 DOI: 10.1111/mpp.12893] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Ustilago maydis is a model organism for the study of biotrophic plant-pathogen interactions. The sexual and pathogenic development of the fungus are tightly connected since fusion of compatible haploid sporidia is prerequisite for infection of the host plant, maize (Zea mays). After plant penetration, the unfolded protein response (UPR) is activated and required for biotrophic growth. The UPR is continuously active throughout all stages of pathogenic development in planta. However, since development of UPR deletion mutants stops directly after plant penetration, the role of an active UPR at later stages of development remained to be determined. Here, we established a gene expression system for U. maydis that uses endogenous, conditionally active promoters to either induce or repress expression of a gene of interest during different stages of plant infection. Integration of the expression constructs into the native genomic locus and removal of resistance cassettes were required to obtain a wild-type-like expression pattern. This indicates that genomic localization and chromatin structure are important for correct promoter activity and gene expression. By conditional expression of the central UPR regulator, Cib1, in U. maydis, we show that a functional UPR is required for continuous plant defence suppression after host infection and that U. maydis relies on a robust control system to prevent deleterious UPR hyperactivation.
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Affiliation(s)
- Lara Schmitz
- Institute for Microbiology and GeneticsDepartment of Molecular Microbiology and GeneticsGöttingen Center for Molecular Biosciences (GZMB)University of GöttingenGrisebachstr. 8D‐37077GöttingenGermany
- International Research Training Group 2172 PRoTECTGöttingen, VancouverGermany
| | - James W. Kronstad
- International Research Training Group 2172 PRoTECTGöttingen, VancouverGermany
- Michael Smith LaboratoriesDepartment of Microbiology and ImmunologyUniversity of British ColumbiaVancouverBCV6T 1Z4Canada
| | - Kai Heimel
- Institute for Microbiology and GeneticsDepartment of Molecular Microbiology and GeneticsGöttingen Center for Molecular Biosciences (GZMB)University of GöttingenGrisebachstr. 8D‐37077GöttingenGermany
- International Research Training Group 2172 PRoTECTGöttingen, VancouverGermany
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The Unfolded Protein Response Regulates Pathogenic Development of Ustilago maydis by Rok1-Dependent Inhibition of Mating-Type Signaling. mBio 2019; 10:mBio.02756-19. [PMID: 31848283 PMCID: PMC6918084 DOI: 10.1128/mbio.02756-19] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The unfolded protein response (UPR) is crucial for endoplasmic reticulum (ER) homeostasis and disease development in fungal pathogens. In the plant-pathogenic fungus Ustilago maydis, the UPR supports fungal proliferation in planta and effector secretion for plant defense suppression. In this study, we uncovered that UPR activity, which is normally restricted to the biotrophic stage in planta, inhibits mating and the formation of infectious filaments by Rok1-dependent dephosphorylation of the pheromone responsive mitogen-activated protein kinase (MAPK) Kpp2. This observation is relevant for understanding how the fungal virulence program is regulated by cellular physiology. UPR-mediated control of mating-type signaling pathways predicts that effector gene expression and the virulence potential are controlled by ER stress levels. Fungal pathogens require the unfolded protein response (UPR) to maintain protein homeostasis of the endoplasmic reticulum (ER) during pathogenic development. In the corn smut fungus Ustilago maydis, pathogenic development is controlled by the a and b mating-type loci. The UPR is specifically activated after plant penetration and required for efficient secretion of effectors and suppression of the plant defense response. The interaction between the UPR regulator Cib1 and the central developmental regulator Clp1 modulates the pathogenic program and triggers fungal colonization of the host plant. By contrast, when activated before plant penetration, the UPR interferes with fungal virulence by reducing expression of bE and bW, the central regulators of pathogenic development encoded by the b mating-type locus. Here, we show that this inhibitory effect results from UPR-mediated suppression of the pheromone response pathway upstream of the b regulatory network. UPR activity prompts dephosphorylation of the pheromone-responsive mitogen-activated protein kinase (MAPK) Kpp2, reducing activity of the pheromone response factor Prf1 that regulates expression of bE and bW. Deletion of the dual specificity phosphatase rok1 fully suppressed UPR-dependent inhibition of Kpp2 phosphorylation, formation of infectious filaments, and fungal virulence. Rok1 determines the activity of mating-type signaling pathways and thus the degree of fungal virulence. We propose that UPR-dependent regulation of Rok1 aligns ER physiology with fungal aggressiveness and effector gene expression during biotrophic growth of U. maydis in the host plant.
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11
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N-glycosylation of the protein disulfide isomerase Pdi1 ensures full Ustilago maydis virulence. PLoS Pathog 2019; 15:e1007687. [PMID: 31730668 PMCID: PMC6881057 DOI: 10.1371/journal.ppat.1007687] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 11/27/2019] [Accepted: 09/22/2019] [Indexed: 11/19/2022] Open
Abstract
Fungal pathogenesis depends on accurate secretion and location of virulence factors which drive host colonization. Protein glycosylation is a common posttranslational modification of cell wall components and other secreted factors, typically required for correct protein localization, secretion and function. Thus, the absence of glycosylation is associated with animal and plant pathogen avirulence. While the relevance of protein glycosylation for pathogenesis has been well established, the main glycoproteins responsible for the loss of virulence observed in glycosylation-defective fungi have not been identified. Here, we devise a proteomics approach to identify such proteins and use it to demonstrate a role for the highly conserved protein disulfide isomerase Pdi1 in virulence. We show that efficient Pdi1 N-glycosylation, which promotes folding into the correct protein conformation, is required for full pathogenic development of the corn smut fungus Ustilago maydis. Remarkably, the observed virulence defects are reminiscent of those seen in glycosylation-defective cells suggesting that the N-glycosylation of Pdi1 is necessary for the full secretion of virulence factors. All these observations, together with the fact that Pdi1 protein and RNA expression levels rise upon virulence program induction, suggest that Pdi1 glycosylation is important for normal pathogenic development in U. maydis. Our results provide new insights into the role of glycosylation in fungal pathogenesis.
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Zhang Y, Yin Y, Hu P, Yu J, Xia W, Ge Q, Cao Q, Cui H, Yu X, Ye Z. Mating-type loci of Ustilago esculenta are essential for mating and development. Fungal Genet Biol 2019; 125:60-70. [PMID: 30685508 DOI: 10.1016/j.fgb.2019.01.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 01/16/2019] [Accepted: 01/17/2019] [Indexed: 11/19/2022]
Abstract
Ustilago esculenta is closely related to the smut fungus Ustilago maydis and, in an endophytic-like life in the plant Zizania latifolia, only infects host stems and causes swollen stems to form edible galls called Jiaobai in China. In order to study its different modes of invasion and sites of symptom development from other smut fungi at the molecular level, we first characterized the a and b mating-type loci of U. esculenta. The a loci contained three a mating-type alleles, encoding two pheromones and one pheromone receptor per allele. The pheromone/receptor system controlled the conjugation formation, the initial step of mating, in which each pheromone was specific for recognition by only one mating partner. In addition, there are at least three b alleles identified in U. esculenta, encoding two subunits of heterodimeric homeodomain transcription factors bE and bW, responsible for hyphal growth and invasiveness. Hyphal formation, elongation and invasion after mating of two compatible partners occurred, only when a heterodimer complex was formed by the bE and bW proteins derived from different alleles. We also demonstrated that even with only one paired pheromone-pheromone receptor, the active b locus heterodimer triggered hyphal growth and infection.
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Affiliation(s)
- Yafen Zhang
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection & Quarantine, College of Life Sciences, China Jiliang University, Hangzhou, China
| | - Yumei Yin
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection & Quarantine, College of Life Sciences, China Jiliang University, Hangzhou, China
| | - Peng Hu
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection & Quarantine, College of Life Sciences, China Jiliang University, Hangzhou, China
| | - Jiajia Yu
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection & Quarantine, College of Life Sciences, China Jiliang University, Hangzhou, China
| | - Wenqiang Xia
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection & Quarantine, College of Life Sciences, China Jiliang University, Hangzhou, China
| | - Qianwen Ge
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection & Quarantine, College of Life Sciences, China Jiliang University, Hangzhou, China
| | - Qianchao Cao
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection & Quarantine, College of Life Sciences, China Jiliang University, Hangzhou, China
| | - Haifeng Cui
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection & Quarantine, College of Life Sciences, China Jiliang University, Hangzhou, China
| | - Xiaoping Yu
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection & Quarantine, College of Life Sciences, China Jiliang University, Hangzhou, China
| | - Zihong Ye
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection & Quarantine, College of Life Sciences, China Jiliang University, Hangzhou, China.
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Schmitz L, McCotter S, Kretschmer M, Kronstad JW, Heimel K. Transcripts and tumors: regulatory and metabolic programming during biotrophic phytopathogenesis. F1000Res 2018; 7. [PMID: 30519451 PMCID: PMC6248262 DOI: 10.12688/f1000research.16404.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/12/2018] [Indexed: 01/05/2023] Open
Abstract
Biotrophic fungal pathogens of plants must sense and adapt to the host environment to complete their life cycles. Recent transcriptome studies of the infection of maize by the biotrophic pathogen
Ustilago maydis are providing molecular insights into an ordered program of changes in gene expression and the deployment of effectors as well as key features of nutrient acquisition. In particular, the transcriptome data provide a deeper appreciation of the complexity of the transcription factor network that controls the biotrophic program of invasion, proliferation, and sporulation. Additionally, transcriptome analysis during tumor formation, a key late stage in the life cycle, revealed features of the remodeling of host and pathogen metabolism that may support the formation of tremendous numbers of spores. Transcriptome studies are also appearing for other smut species during interactions with their hosts, thereby providing opportunities for comparative approaches to understand biotrophic adaptation.
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Affiliation(s)
- Lara Schmitz
- Institute for Microbiology and Genetics, Department of Molecular Microbiology and Genetics, Georg-August-University-Göttingen, Göttingen, Lower Saxony, D-37077, Germany
| | - Sean McCotter
- Michael Smith Laboratories, Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Matthias Kretschmer
- Michael Smith Laboratories, Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - James W Kronstad
- Michael Smith Laboratories, Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Kai Heimel
- Institute for Microbiology and Genetics, Department of Molecular Microbiology and Genetics, Georg-August-University-Göttingen, Göttingen, Lower Saxony, D-37077, Germany
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14
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Riquelme M, Aguirre J, Bartnicki-García S, Braus GH, Feldbrügge M, Fleig U, Hansberg W, Herrera-Estrella A, Kämper J, Kück U, Mouriño-Pérez RR, Takeshita N, Fischer R. Fungal Morphogenesis, from the Polarized Growth of Hyphae to Complex Reproduction and Infection Structures. Microbiol Mol Biol Rev 2018; 82:e00068-17. [PMID: 29643171 PMCID: PMC5968459 DOI: 10.1128/mmbr.00068-17] [Citation(s) in RCA: 183] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Filamentous fungi constitute a large group of eukaryotic microorganisms that grow by forming simple tube-like hyphae that are capable of differentiating into more-complex morphological structures and distinct cell types. Hyphae form filamentous networks by extending at their tips while branching in subapical regions. Rapid tip elongation requires massive membrane insertion and extension of the rigid chitin-containing cell wall. This process is sustained by a continuous flow of secretory vesicles that depends on the coordinated action of the microtubule and actin cytoskeletons and the corresponding motors and associated proteins. Vesicles transport cell wall-synthesizing enzymes and accumulate in a special structure, the Spitzenkörper, before traveling further and fusing with the tip membrane. The place of vesicle fusion and growth direction are enabled and defined by the position of the Spitzenkörper, the so-called cell end markers, and other proteins involved in the exocytic process. Also important for tip extension is membrane recycling by endocytosis via early endosomes, which function as multipurpose transport vehicles for mRNA, septins, ribosomes, and peroxisomes. Cell integrity, hyphal branching, and morphogenesis are all processes that are largely dependent on vesicle and cytoskeleton dynamics. When hyphae differentiate structures for asexual or sexual reproduction or to mediate interspecies interactions, the hyphal basic cellular machinery may be reprogrammed through the synthesis of new proteins and/or the modification of protein activity. Although some transcriptional networks involved in such reprogramming of hyphae are well studied in several model filamentous fungi, clear connections between these networks and known determinants of hyphal morphogenesis are yet to be established.
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Affiliation(s)
- Meritxell Riquelme
- Department of Microbiology, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, Baja California, Mexico
| | - Jesús Aguirre
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de Mexico, Mexico City, Mexico
| | - Salomon Bartnicki-García
- Department of Microbiology, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, Baja California, Mexico
| | - Gerhard H Braus
- Department of Molecular Microbiology and Genetics and Goettingen Center for Molecular Biosciences (GZMB), University of Goettingen, Goettingen, Germany
| | - Michael Feldbrügge
- Institute for Microbiology, Heinrich Heine University Düsseldorf, Cluster of Excellence on Plant Sciences, Düsseldorf, Germany
| | - Ursula Fleig
- Institute for Functional Genomics of Microorganisms, Heinrich Heine University Düsseldorf, Cluster of Excellence on Plant Sciences, Düsseldorf, Germany
| | - Wilhelm Hansberg
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de Mexico, Mexico City, Mexico
| | - Alfredo Herrera-Estrella
- Laboratorio Nacional de Genómica para la Biodiversidad, Centro de Investigación y de Estudios Avanzados del IPN, Irapuato, Mexico
| | - Jörg Kämper
- Karlsruhe Institute of Technology-South Campus, Institute for Applied Biosciences, Karlsruhe, Germany
| | - Ulrich Kück
- Ruhr University Bochum, Lehrstuhl für Allgemeine und Molekulare Botanik, Bochum, Germany
| | - Rosa R Mouriño-Pérez
- Department of Microbiology, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, Baja California, Mexico
| | - Norio Takeshita
- University of Tsukuba, Faculty of Life and Environmental Sciences, Tsukuba, Japan
| | - Reinhard Fischer
- Karlsruhe Institute of Technology-South Campus, Institute for Applied Biosciences, Karlsruhe, Germany
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15
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Hadjivasiliou Z, Pomiankowski A. Gamete signalling underlies the evolution of mating types and their number. Philos Trans R Soc Lond B Biol Sci 2017; 371:rstb.2015.0531. [PMID: 27619695 PMCID: PMC5031616 DOI: 10.1098/rstb.2015.0531] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/11/2016] [Indexed: 01/02/2023] Open
Abstract
The gametes of unicellular eukaryotes are morphologically identical, but are nonetheless divided into distinct mating types. The number of mating types varies enormously and can reach several thousand, yet most species have only two. Why do morphologically identical gametes need to be differentiated into self-incompatible mating types, and why is two the most common number of mating types? In this work, we explore a neglected hypothesis that there is a need for asymmetric signalling interactions between mating partners. Our review shows that isogamous gametes always interact asymmetrically throughout sex and argue that this asymmetry is favoured because it enhances the efficiency of the mating process. We further develop a simple mathematical model that allows us to study the evolution of the number of mating types based on the strength of signalling interactions between gametes. Novel mating types have an advantage as they are compatible with all others and rarely meet their own type. But if existing mating types coevolve to have strong mutual interactions, this restricts the spread of novel types. Similarly, coevolution is likely to drive out less attractive mating types. These countervailing forces specify the number of mating types that are evolutionarily stable. This article is part of the themed issue ‘Weird sex: the underappreciated diversity of sexual reproduction’.
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Affiliation(s)
- Zena Hadjivasiliou
- Centre for Mathematics and Physics in the Life Sciences and Experimental Biology, University College London, Gower Street, London WC1E 6BT, UK Department of Genetics, Evolution and Environment, University College London, Gower Street, London WC1E 6BT, UK
| | - Andrew Pomiankowski
- Centre for Mathematics and Physics in the Life Sciences and Experimental Biology, University College London, Gower Street, London WC1E 6BT, UK Department of Genetics, Evolution and Environment, University College London, Gower Street, London WC1E 6BT, UK
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16
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van der Does HC, Rep M. Adaptation to the Host Environment by Plant-Pathogenic Fungi. ANNUAL REVIEW OF PHYTOPATHOLOGY 2017; 55:427-450. [PMID: 28645233 DOI: 10.1146/annurev-phyto-080516-035551] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Many fungi can live both saprophytically and as endophyte or pathogen inside a living plant. In both environments, complex organic polymers are used as sources of nutrients. Propagation inside a living host also requires the ability to respond to immune responses of the host. We review current knowledge of how plant-pathogenic fungi do this. First, we look at how fungi change their global gene expression upon recognition of the host environment, leading to secretion of effectors, enzymes, and secondary metabolites; changes in metabolism; and defense against toxic compounds. Second, we look at what is known about the various cues that enable fungi to sense the presence of living plant cells. Finally, we review literature on transcription factors that participate in gene expression in planta or are suspected to be involved in that process because they are required for the ability to cause disease.
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Affiliation(s)
| | - Martijn Rep
- Molecular Plant Pathology, University of Amsterdam, 1098XH Amsterdam, The Netherlands;
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17
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Moretti M, Wang L, Grognet P, Lanver D, Link H, Kahmann R. Three regulators of G protein signaling differentially affect mating, morphology and virulence in the smut fungusUstilago maydis. Mol Microbiol 2017; 105:901-921. [DOI: 10.1111/mmi.13745] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/06/2017] [Indexed: 12/30/2022]
Affiliation(s)
- Marino Moretti
- Department of Organismic Interactions; Max Planck Institute for Terrestrial Microbiology; Karl-von-Frisch-Strasse 10, Marburg D-35043 Germany
| | - Lei Wang
- Department of Organismic Interactions; Max Planck Institute for Terrestrial Microbiology; Karl-von-Frisch-Strasse 10, Marburg D-35043 Germany
| | - Pierre Grognet
- Department of Organismic Interactions; Max Planck Institute for Terrestrial Microbiology; Karl-von-Frisch-Strasse 10, Marburg D-35043 Germany
| | - Daniel Lanver
- Department of Organismic Interactions; Max Planck Institute for Terrestrial Microbiology; Karl-von-Frisch-Strasse 10, Marburg D-35043 Germany
| | - Hannes Link
- Dynamic Control of Metabolic Networks; Max Planck Institute for Terrestrial Microbiology; Karl-von-Frisch-Strasse 16, Marburg D-35043 Germany
| | - Regine Kahmann
- Department of Organismic Interactions; Max Planck Institute for Terrestrial Microbiology; Karl-von-Frisch-Strasse 10, Marburg D-35043 Germany
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18
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Coelho MA, Bakkeren G, Sun S, Hood ME, Giraud T. Fungal Sex: The Basidiomycota. Microbiol Spectr 2017; 5:10.1128/microbiolspec.FUNK-0046-2016. [PMID: 28597825 PMCID: PMC5467461 DOI: 10.1128/microbiolspec.funk-0046-2016] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Indexed: 12/29/2022] Open
Abstract
Fungi of the Basidiomycota, representing major pathogen lineages and mushroom-forming species, exhibit diverse means to achieve sexual reproduction, with particularly varied mechanisms to determine compatibilities of haploid mating partners. For species that require mating between distinct genotypes, discrimination is usually based on both the reciprocal exchange of diffusible mating pheromones, rather than sexes, and the interactions of homeodomain protein signals after cell fusion. Both compatibility factors must be heterozygous in the product of mating, and genetic linkage relationships of the mating pheromone/receptor and homeodomain genes largely determine the complex patterns of mating-type variation. Independent segregation of the two compatibility factors can create four haploid mating genotypes from meiosis, referred to as tetrapolarity. This condition is thought to be ancestral to the basidiomycetes. Alternatively, cosegregation by linkage of the two mating factors, or in some cases the absence of the pheromone-based discrimination, yields only two mating types from meiosis, referred to as bipolarity. Several species are now known to have large and highly rearranged chromosomal regions linked to mating-type genes. At the population level, polymorphism of the mating-type genes is an exceptional aspect of some basidiomycete fungi, where selection under outcrossing for rare, intercompatible allelic variants is thought to be responsible for numbers of mating types that may reach several thousand. Advances in genome sequencing and assembly are yielding new insights by comparative approaches among and within basidiomycete species, with the promise to resolve the evolutionary origins and dynamics of mating compatibility genetics in this major eukaryotic lineage.
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Affiliation(s)
- Marco A. Coelho
- UCIBIO-REQUIMTE, Departamento de Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal
| | - Guus Bakkeren
- Agriculture and Agri-Food Canada, Summerland Research and Development Centre Summerland, BC, V0H 1Z0, Canada
| | - Sheng Sun
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Michael E. Hood
- Department of Biology, Amherst College, 01002-5000 Amherst, Massachusetts, USA
| | - Tatiana Giraud
- Ecologie Systématique Evolution, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, 91400, Orsay, France
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19
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Comparative Analysis Highlights Variable Genome Content of Wheat Rusts and Divergence of the Mating Loci. G3-GENES GENOMES GENETICS 2017; 7:361-376. [PMID: 27913634 PMCID: PMC5295586 DOI: 10.1534/g3.116.032797] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Three members of the Puccinia genus, Pucciniatriticina (Pt), Pstriiformis f.sp. tritici (Pst), and Pgraminis f.sp. tritici (Pgt), cause the most common and often most significant foliar diseases of wheat. While similar in biology and life cycle, each species is uniquely adapted and specialized. The genomes of Pt and Pst were sequenced and compared to that of Pgt to identify common and distinguishing gene content, to determine gene variation among wheat rust pathogens, other rust fungi, and basidiomycetes, and to identify genes of significance for infection. Pt had the largest genome of the three, estimated at 135 Mb with expansion due to mobile elements and repeats encompassing 50.9% of contig bases; in comparison, repeats occupy 31.5% for Pst and 36.5% for Pgt We find all three genomes are highly heterozygous, with Pst [5.97 single nucleotide polymorphisms (SNPs)/kb] nearly twice the level detected in Pt (2.57 SNPs/kb) and that previously reported for Pgt Of 1358 predicted effectors in Pt, 784 were found expressed across diverse life cycle stages including the sexual stage. Comparison to related fungi highlighted the expansion of gene families involved in transcriptional regulation and nucleotide binding, protein modification, and carbohydrate degradation enzymes. Two allelic homeodomain pairs, HD1 and HD2, were identified in each dikaryotic Puccinia species along with three pheromone receptor (STE3) mating-type genes, two of which are likely representing allelic specificities. The HD proteins were active in a heterologous Ustilago maydis mating assay and host-induced gene silencing (HIGS) of the HD and STE3 alleles reduced wheat host infection.
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20
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Yan M, Cai E, Zhou J, Chang C, Xi P, Shen W, Li L, Jiang Z, Deng YZ, Zhang LH. A Dual-Color Imaging System for Sugarcane Smut Fungus Sporisorium scitamineum. PLANT DISEASE 2016; 100:2357-2362. [PMID: 30686163 DOI: 10.1094/pdis-02-16-0257-sr] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The life cycle of the sugarcane smut fungus Sporisorium scitamineum is a multistep process. Haploid sporidia of compatible (MAT-1 versus MAT-2) mating types fuse to generate pathogenic dikaryotic hyphae to infect the host. Within the host tissues, diploid teliospores are formed and induce a characteristic sorus that looks like a black whip. The diploid teliospores germinate to form haploid sporidia by meiosis. In order to monitor fungal development throughout the whole life cycle, we expressed the green fluorescent protein (GFP) and red fluorescent protein (RFP) in S. scitamineum MAT-1 and MAT-2 sporidia, respectively. Observation by epifluorescence microscope showed that conjugation tube formation and sporidia fusion occurred at 4 to 8 h, and formation of dikaryotic filaments was detected at 12 h after mating. The resultant teliospores, with diffused GFP and RFP, underwent meiosis as demonstrated by septated hypha with single fluorescent signal. We demonstrated that GFP- and RFP-tagged strains can be used to study the life cycle development of the fungal pathogen S. scitamineum, including the sexual mating and meiosis events. This dual-color imaging system would be a valuable tool for investigation of biotic and abiotic factors that might affect the fungal life cycle development and pathogenesis.
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Affiliation(s)
- Meixin Yan
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, P. R. China, and Biotechnology Research Institute, Guangxi Academy of Agricultural Sciences, Guangxi, P. R. China
| | - Enping Cai
- Guangdong Innovative and Entrepreneurial Research Team of Sociomicrobiology Basic Science and Frontier Technology
| | - Jianuan Zhou
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, P. R. China
| | - Changqing Chang
- Guangdong Innovative and Entrepreneurial Research Team of Sociomicrobiology Basic Science and Frontier Technology, and Key Laboratory of Bio-Pesticide Innovation and Application of Guangdong Province, South China Agricultural University, Guangzhou, P. R. China
| | - Pinggen Xi
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, P. R. China
| | - Wankuan Shen
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, P. R. China
| | - Lingyu Li
- Guangdong Innovative and Entrepreneurial Research Team of Sociomicrobiology Basic Science and Frontier Technology
| | - Zide Jiang
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, P. R. China
| | - Yi Zhen Deng
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, P. R. China
| | - Lian-Hui Zhang
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, P. R. China
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21
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van der Does HC, Fokkens L, Yang A, Schmidt SM, Langereis L, Lukasiewicz JM, Hughes TR, Rep M. Transcription Factors Encoded on Core and Accessory Chromosomes of Fusarium oxysporum Induce Expression of Effector Genes. PLoS Genet 2016; 12:e1006401. [PMID: 27855160 PMCID: PMC5140021 DOI: 10.1371/journal.pgen.1006401] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 10/04/2016] [Indexed: 12/24/2022] Open
Abstract
Proteins secreted by pathogens during host colonization largely determine the outcome of pathogen-host interactions and are commonly called 'effectors'. In fungal plant pathogens, coordinated transcriptional up-regulation of effector genes is a key feature of pathogenesis and effectors are often encoded in genomic regions with distinct repeat content, histone code and rate of evolution. In the tomato pathogen Fusarium oxysporum f. sp. lycopersici (Fol), effector genes reside on one of four accessory chromosomes, known as the 'pathogenicity' chromosome, which can be exchanged between strains through horizontal transfer. The three other accessory chromosomes in the Fol reference strain may also be important for virulence towards tomato. Expression of effector genes in Fol is highly up-regulated upon infection and requires Sge1, a transcription factor encoded on the core genome. Interestingly, the pathogenicity chromosome itself contains 13 predicted transcription factor genes and for all except one, there is a homolog on the core genome. We determined DNA binding specificity for nine transcription factors using oligonucleotide arrays. The binding sites for homologous transcription factors were highly similar, suggesting that extensive neofunctionalization of DNA binding specificity has not occurred. Several DNA binding sites are enriched on accessory chromosomes, and expression of FTF1, its core homolog FTF2 and SGE1 from a constitutive promoter can induce expression of effector genes. The DNA binding sites of only these three transcription factors are enriched among genes up-regulated during infection. We further show that Ftf1, Ftf2 and Sge1 can activate transcription from their binding sites in yeast. RNAseq analysis revealed that in strains with constitutive expression of FTF1, FTF2 or SGE1, expression of a similar set of plant-responsive genes on the pathogenicity chromosome is induced, including most effector genes. We conclude that the Fol pathogenicity chromosome may be partially transcriptionally autonomous, but there are also extensive transcriptional connections between core and accessory chromosomes.
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Affiliation(s)
| | - Like Fokkens
- Molecular Plant Pathology, University of Amsterdam, The Netherlands
| | - Ally Yang
- Banting and Best Department of Medical Research, University of Toronto, Toronto, ON, Canada
| | - Sarah M. Schmidt
- Molecular Plant Pathology, University of Amsterdam, The Netherlands
| | - Léon Langereis
- Molecular Plant Pathology, University of Amsterdam, The Netherlands
| | | | - Timothy R. Hughes
- Banting and Best Department of Medical Research, University of Toronto, Toronto, ON, Canada
| | - Martijn Rep
- Molecular Plant Pathology, University of Amsterdam, The Netherlands
- * E-mail:
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22
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Tollot M, Assmann D, Becker C, Altmüller J, Dutheil JY, Wegner CE, Kahmann R. The WOPR Protein Ros1 Is a Master Regulator of Sporogenesis and Late Effector Gene Expression in the Maize Pathogen Ustilago maydis. PLoS Pathog 2016; 12:e1005697. [PMID: 27332891 PMCID: PMC4917244 DOI: 10.1371/journal.ppat.1005697] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 05/20/2016] [Indexed: 12/31/2022] Open
Abstract
The biotrophic basidiomycete fungus Ustilago maydis causes smut disease in maize. Hallmarks of the disease are large tumors that develop on all aerial parts of the host in which dark pigmented teliospores are formed. We have identified a member of the WOPR family of transcription factors, Ros1, as major regulator of spore formation in U. maydis. ros1 expression is induced only late during infection and hence Ros1 is neither involved in plant colonization of dikaryotic fungal hyphae nor in plant tumor formation. However, during late stages of infection Ros1 is essential for fungal karyogamy, massive proliferation of diploid fungal cells and spore formation. Premature expression of ros1 revealed that Ros1 counteracts the b-dependent filamentation program and induces morphological alterations resembling the early steps of sporogenesis. Transcriptional profiling and ChIP-seq analyses uncovered that Ros1 remodels expression of about 30% of all U. maydis genes with 40% of these being direct targets. In total the expression of 80 transcription factor genes is controlled by Ros1. Four of the upregulated transcription factor genes were deleted and two of the mutants were affected in spore development. A large number of b-dependent genes were differentially regulated by Ros1, suggesting substantial changes in this regulatory cascade that controls filamentation and pathogenic development. Interestingly, 128 genes encoding secreted effectors involved in the establishment of biotrophic development were downregulated by Ros1 while a set of 70 “late effectors” was upregulated. These results indicate that Ros1 is a master regulator of late development in U. maydis and show that the biotrophic interaction during sporogenesis involves a drastic shift in expression of the fungal effectome including the downregulation of effectors that are essential during early stages of infection. The fungus Ustilago maydis is a pathogen of maize which induces tumor formation in the infected tissue. In these tumors huge amounts of fungal spores develop. As a biotrophic pathogen, U. maydis establishes itself in the plant with the help of a large number of secreted effector proteins. Many effector proteins are important for virulence because they counteract plant defense reactions. In this manuscript we have identified and characterized Ros1, a master regulator for the late stages of U. maydis development. This transcription factor is expressed late during infection and controls nuclear fusion, hyphal aggregation and late proliferation. ros1 mutants are still able to induce tumor formation but these are a dead end because they do not contain any spores. We show that Ros1 interferes with the early regulatory cascade controlled by a complex of two homeodomain proteins. In addition, Ros1 triggers a major switch in the effector repertoire, suggesting that different sets of effectors are needed for different stages of fungal development inside the plant.
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Affiliation(s)
- Marie Tollot
- Max Planck Institute for Terrestrial Microbiology, Department of Organismic Interactions, Marburg, Germany
| | - Daniela Assmann
- Max Planck Institute for Terrestrial Microbiology, Department of Organismic Interactions, Marburg, Germany
| | - Christian Becker
- Cologne Center for Genomics (CCG), University of Cologne, Cologne, Germany
| | - Janine Altmüller
- Cologne Center for Genomics (CCG), University of Cologne, Cologne, Germany
| | - Julien Y. Dutheil
- Max Planck Institute for Terrestrial Microbiology, Department of Organismic Interactions, Marburg, Germany
| | - Carl-Eric Wegner
- Max Planck Institute for Terrestrial Microbiology, Deparment of Biogeochemistry, Marburg, Germany
| | - Regine Kahmann
- Max Planck Institute for Terrestrial Microbiology, Department of Organismic Interactions, Marburg, Germany
- * E-mail:
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23
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Yan M, Dai W, Cai E, Deng YZ, Chang C, Jiang Z, Zhang LH. Transcriptome analysis of Sporisorium scitamineum reveals critical environmental signals for fungal sexual mating and filamentous growth. BMC Genomics 2016; 17:354. [PMID: 27185248 PMCID: PMC4867532 DOI: 10.1186/s12864-016-2691-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Accepted: 05/05/2016] [Indexed: 11/10/2022] Open
Abstract
Background Sporisorium scitamineum causes the sugarcane smut disease, one of the most serious constraints to global sugarcane production. S. scitamineum possesses a sexual mating system composed of two mating-type loci, a and b locus. We previously identified and deleted the b locus in S. scitamineum, and found that the resultant SsΔMAT-1b mutant was defective in mating and pathogenicity. Results To further understand the function of b-mating locus, we carried out transcriptome analysis by comparing the transcripts of the mutant strain SsΔMAT-1b, from which the SsbE1 and SsbW1 homeodomain transcription factors have previously been deleted, with those from the wild-type MAT-1 strain. Also the transcripts from SsΔMAT-1b X MAT-2 were compared with those from wild-type MAT-1 X MAT-2 mating. A total of 209 genes were up-regulated (p < 0.05) in the SsΔMAT-1b mutant, compared to the wild-type MAT-1 strain, while 148 genes down-regulated (p < 0.05). In the mixture, 120 genes were up-regulated (p < 0.05) in SsΔMAT-1b X MAT-2, which failed to mate, compared to the wild-type MAT-1 X MAT-2 mating, and 271 genes down-regulated (p < 0.05). By comparing the up- and down-regulated genes in these two sets, it was found that 15 up-regulated and 37 down-regulated genes were common in non-mating haploid and mating mixture, which indeed could be genes regulated by b-locus. Furthermore, GO and KEGG enrichment analysis suggested that carbon metabolism pathway and stress response mediated by Hog1 MAPK signaling pathway were altered in the non-mating sets. Conclusions Experimental validation results indicate that the bE/bW heterodimeric transcriptional factor, encoded by the b-locus, could regulate S. scitamineum sexual mating and/or filamentous growth via modulating glucose metabolism and Hog1-mediating oxidative response. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-2691-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Meixin Yan
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Agriculture, South China Agricultural University, Guangzhou, Peoples' Republic of China.,Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, Peoples' Republic of China
| | - Weijun Dai
- Guangdong Innovative and Entepreneurial Research Team of Sociomicrobiology Basic Science and Frontier Technology, South China Agricultural University, Guangzhou, Peoples' Republic of China.,Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, Peoples' Republic of China
| | - Enping Cai
- Guangdong Innovative and Entepreneurial Research Team of Sociomicrobiology Basic Science and Frontier Technology, South China Agricultural University, Guangzhou, Peoples' Republic of China.,Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, Peoples' Republic of China
| | - Yi Zhen Deng
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Agriculture, South China Agricultural University, Guangzhou, Peoples' Republic of China.,Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, Peoples' Republic of China
| | - Changqing Chang
- Guangdong Innovative and Entepreneurial Research Team of Sociomicrobiology Basic Science and Frontier Technology, South China Agricultural University, Guangzhou, Peoples' Republic of China.,Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, Peoples' Republic of China
| | - Zide Jiang
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Agriculture, South China Agricultural University, Guangzhou, Peoples' Republic of China.
| | - Lian-Hui Zhang
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Agriculture, South China Agricultural University, Guangzhou, Peoples' Republic of China. .,Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, Peoples' Republic of China.
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Yan M, Zhu G, Lin S, Xian X, Chang C, Xi P, Shen W, Huang W, Cai E, Jiang Z, Deng YZ, Zhang LH. The mating-type locus b of the sugarcane smut Sporisorium scitamineum is essential for mating, filamentous growth and pathogenicity. Fungal Genet Biol 2016; 86:1-8. [DOI: 10.1016/j.fgb.2015.11.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Revised: 11/07/2015] [Accepted: 11/07/2015] [Indexed: 11/29/2022]
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25
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Schuster M, Schweizer G, Reissmann S, Kahmann R. Genome editing in Ustilago maydis using the CRISPR-Cas system. Fungal Genet Biol 2015; 89:3-9. [PMID: 26365384 DOI: 10.1016/j.fgb.2015.09.001] [Citation(s) in RCA: 160] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 09/01/2015] [Accepted: 09/02/2015] [Indexed: 12/26/2022]
Abstract
This communication describes the establishment of the type II bacterial CRISPR-Cas9 system to efficiently disrupt target genes in the fungal maize pathogen Ustilago maydis. A single step transformation of a self-replicating plasmid constitutively expressing the U. maydis codon-optimized cas9 gene and a suitable sgRNA under control of the U. maydis U6 snRNA promoter was sufficient to induce genome editing. On average 70% of the progeny of a single transformant were disrupted within the respective b gene. Without selection the self-replicating plasmid was lost rapidly allowing transient expression of the CRISPR-Cas9 system to minimize potential long-term negative effects of Cas9. This technology will be an important advance for the simultaneous disruption of functionally redundant genes and gene families to investigate their contribution to virulence of U. maydis.
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Affiliation(s)
- Mariana Schuster
- Max Planck Institute for Terrestrial Microbiology, Department of Organismic Interactions, Karl-von-Frisch-Strasse 10, 35043 Marburg, Germany
| | - Gabriel Schweizer
- Max Planck Institute for Terrestrial Microbiology, Department of Organismic Interactions, Karl-von-Frisch-Strasse 10, 35043 Marburg, Germany
| | - Stefanie Reissmann
- Max Planck Institute for Terrestrial Microbiology, Department of Organismic Interactions, Karl-von-Frisch-Strasse 10, 35043 Marburg, Germany
| | - Regine Kahmann
- Max Planck Institute for Terrestrial Microbiology, Department of Organismic Interactions, Karl-von-Frisch-Strasse 10, 35043 Marburg, Germany.
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26
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Genomics and Transcriptomics Analyses of the Oil-Accumulating Basidiomycete Yeast Trichosporon oleaginosus: Insights into Substrate Utilization and Alternative Evolutionary Trajectories of Fungal Mating Systems. mBio 2015. [PMID: 26199329 PMCID: PMC4513080 DOI: 10.1128/mbio.00918-15] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Microbial fermentation of agro-industrial waste holds great potential for reducing the environmental impact associated with the production of lipids for industrial purposes from plant biomass. However, the chemical complexity of many residues currently prevents efficient conversion into lipids, creating a high demand for strains with the ability to utilize all energy-rich components of agricultural residues. Here, we present results of genome and transcriptome analyses of Trichosporon oleaginosus. This oil-accumulating yeast is able to grow on a wide variety of substrates, including pentoses and N-acetylglucosamine, making it an interesting candidate for biotechnological applications. Transcriptomics shows specific changes in gene expression patterns under lipid-accumulating conditions. Furthermore, gene content and expression analyses indicate that T. oleaginosus is well-adapted for the utilization of chitin-rich biomass. We also focused on the T. oleaginosus mating type, because this species is a member of the Tremellomycetes, a group that has been intensively analyzed as a model for the evolution of sexual development, the best-studied member being Cryptococcus neoformans. The structure of the T. oleaginosus mating-type regions differs significantly from that of other Tremellomycetes and reveals a new evolutionary trajectory paradigm. Comparative analysis shows that recruitment of developmental genes to the ancestral tetrapolar mating-type loci occurred independently in the Trichosporon and Cryptococcus lineages, supporting the hypothesis of a trend toward larger mating-type regions in fungi. Finite fossil fuel resources pose sustainability challenges to society and industry. Microbial oils are a sustainable feedstock for biofuel and chemical production that does not compete with food production. We describe genome and transcriptome analyses of the oleaginous yeast Trichosporon oleaginosus, which can accumulate up to 70% of its dry weight as lipids. In contrast to conventional yeasts, this organism not only shows an absence of diauxic effect while fermenting hexoses and pentoses but also effectively utilizes xylose and N-acetylglucosamine, which are building blocks of lignocellulose and chitin, respectively. Transcriptome analysis revealed metabolic networks that govern conversion of xylose or N-acetylglucosamine as well as lipid accumulation. These data form the basis for a targeted strain optimization strategy. Furthermore, analysis of the mating type of T. oleaginosus supports the hypothesis of a trend toward larger mating-type regions in fungi, similar to the evolution of sex chromosomes in animals and plants.
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27
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Böhm J, Dahlmann TA, Gümüşer H, Kück U. A MAT1-2 wild-type strain from Penicillium chrysogenum: functional mating-type locus characterization, genome sequencing and mating with an industrial penicillin-producing strain. Mol Microbiol 2015; 95:859-74. [PMID: 25521009 PMCID: PMC4357460 DOI: 10.1111/mmi.12909] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/12/2014] [Indexed: 01/07/2023]
Abstract
In heterothallic ascomycetes, mating is controlled by two nonallelic idiomorphs that determine the 'sex' of the corresponding strains. We recently discovered mating-type loci and a sexual life cycle in the penicillin-producing fungus, Penicillium chrysogenum. All industrial penicillin production strains worldwide are derived from a MAT1-1 isolate. No MAT1-2 strain has been investigated in detail until now. Here, we provide the first functional analysis of a MAT1-2 locus from a wild-type strain. Similar to MAT1-1, the MAT1-2 locus has functions beyond sexual development. Unlike MAT1-1, the MAT1-2 locus affects germination and surface properties of conidiospores and controls light-dependent asexual sporulation. Mating of the MAT1-2 wild type with a MAT1-1 high penicillin producer generated sexual spores. We determined the genomic sequences of parental and progeny strains using next-generation sequencing and found evidence for genome-wide recombination. SNP calling showed that derived industrial strains had an uneven distribution of point mutations compared with the wild type. We found evidence for meiotic recombination in all chromosomes. Our results point to a strategy combining the use of mating-type genes, genetics, and next-generation sequencing to optimize conventional strain improvement methods.
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Affiliation(s)
- Julia Böhm
- Christian Doppler Laboratory for Fungal Biotechnology, Lehrstuhl für Allgemeine und Molekulare Botanik, Ruhr-Universität BochumUniversitätsstr. 150, D-44780, Bochum, Germany
| | - Tim A Dahlmann
- Christian Doppler Laboratory for Fungal Biotechnology, Lehrstuhl für Allgemeine und Molekulare Botanik, Ruhr-Universität BochumUniversitätsstr. 150, D-44780, Bochum, Germany
| | - Hendrik Gümüşer
- Christian Doppler Laboratory for Fungal Biotechnology, Lehrstuhl für Allgemeine und Molekulare Botanik, Ruhr-Universität BochumUniversitätsstr. 150, D-44780, Bochum, Germany
| | - Ulrich Kück
- Christian Doppler Laboratory for Fungal Biotechnology, Lehrstuhl für Allgemeine und Molekulare Botanik, Ruhr-Universität BochumUniversitätsstr. 150, D-44780, Bochum, Germany
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28
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Heimel K. Unfolded protein response in filamentous fungi-implications in biotechnology. Appl Microbiol Biotechnol 2014; 99:121-32. [PMID: 25384707 DOI: 10.1007/s00253-014-6192-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 10/24/2014] [Accepted: 10/27/2014] [Indexed: 01/16/2023]
Abstract
The unfolded protein response (UPR) represents a mechanism to preserve endoplasmic reticulum (ER) homeostasis that is conserved in eukaryotes. ER stress caused by the accumulation of potentially toxic un- or misfolded proteins in the ER triggers UPR activation and the induction of genes important for protein folding in the ER, ER expansion, and transport from and to the ER. Along with this adaptation, the overall capacity for protein secretion is markedly increased by the UPR. In filamentous fungi, various approaches to employ the UPR for improved production of homologous and heterologous proteins have been investigated. As the effects on protein production were strongly dependent on the expressed protein, generally applicable strategies have to be developed. A combination of transcriptomic approaches monitoring secretion stress and basic research on the UPR mechanism provided novel and important insight into the complex regulatory cross-connections between UPR signalling, cellular physiology, and developmental processes. It will be discussed how this increasing knowledge on the UPR might stimulate the development of novel strategies for using the UPR as a tool in biotechnology.
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Affiliation(s)
- Kai Heimel
- Institut für Mikrobiologie & Genetik, Georg-August-Universität, Grisebachstr. 8, 37077, Göttingen, Germany,
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29
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Brefort T, Tanaka S, Neidig N, Doehlemann G, Vincon V, Kahmann R. Characterization of the largest effector gene cluster of Ustilago maydis. PLoS Pathog 2014; 10:e1003866. [PMID: 24992561 PMCID: PMC4081774 DOI: 10.1371/journal.ppat.1003866] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Accepted: 11/20/2013] [Indexed: 12/21/2022] Open
Abstract
In the genome of the biotrophic plant pathogen Ustilago maydis, many of the genes coding for secreted protein effectors modulating virulence are arranged in gene clusters. The vast majority of these genes encode novel proteins whose expression is coupled to plant colonization. The largest of these gene clusters, cluster 19A, encodes 24 secreted effectors. Deletion of the entire cluster results in severe attenuation of virulence. Here we present the functional analysis of this genomic region. We show that a 19A deletion mutant behaves like an endophyte, i.e. is still able to colonize plants and complete the infection cycle. However, tumors, the most conspicuous symptoms of maize smut disease, are only rarely formed and fungal biomass in infected tissue is significantly reduced. The generation and analysis of strains carrying sub-deletions identified several genes significantly contributing to tumor formation after seedling infection. Another of the effectors could be linked specifically to anthocyanin induction in the infected tissue. As the individual contributions of these genes to tumor formation were small, we studied the response of maize plants to the whole cluster mutant as well as to several individual mutants by array analysis. This revealed distinct plant responses, demonstrating that the respective effectors have discrete plant targets. We propose that the analysis of plant responses to effector mutant strains that lack a strong virulence phenotype may be a general way to visualize differences in effector function.
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Affiliation(s)
- Thomas Brefort
- Max Planck Institute for Terrestrial Microbiology, Department of Organismic Interactions, Marburg, Germany
| | - Shigeyuki Tanaka
- Max Planck Institute for Terrestrial Microbiology, Department of Organismic Interactions, Marburg, Germany
| | - Nina Neidig
- Max Planck Institute for Terrestrial Microbiology, Department of Organismic Interactions, Marburg, Germany
| | - Gunther Doehlemann
- Max Planck Institute for Terrestrial Microbiology, Department of Organismic Interactions, Marburg, Germany
| | - Volker Vincon
- Max Planck Institute for Terrestrial Microbiology, Department of Organismic Interactions, Marburg, Germany
| | - Regine Kahmann
- Max Planck Institute for Terrestrial Microbiology, Department of Organismic Interactions, Marburg, Germany
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30
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Agarwal C, Aulakh KB, Edelen K, Cooper M, Wallen RM, Adams S, Schultz DJ, Perlin MH. Ustilago maydis phosphodiesterases play a role in the dimorphic switch and in pathogenicity. MICROBIOLOGY-SGM 2013; 159:857-868. [PMID: 23475947 DOI: 10.1099/mic.0.061234-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Components of the cAMP (cyclic AMP) signalling cascades are conserved from fungi to humans, and are particularly important for fungal dimorphism and pathogenicity. Previous work has described two phosphodiesterases, UmPde1 and UmPde2, in Ustilago maydis which show strong phosphodiesterase activity. We further characterized the biological function(s) of these phosphodiesterases in U. maydis. Specifically, we examined their possible role(s) in regulation of the cAMP-dependent protein kinase A (PKA) pathway and their roles in filamentous growth and pathogenicity. We found that UmPde1, which shares 35 % similarity with Cryptococcus neoformans Pde1, also displays functional homology with this enzyme. UmPde1 complements the capsule-formation defect of C. neoformans strains deleted for Pde1. In U. maydis, the cell morphology of the umpde1 deletion mutant resembled the multiple budding phenotypes seen with the ubc1 mutant, which lacks the regulatory subunit of PKA. Interestingly, on low-ammonium medium, umpde2 deletion strains showed a reduction in filamentation that was comparable to that of ubc1 deletion strains; however, umpde1 deletion strains showed normal filamentation on low-ammonium medium. Furthermore, both the ubc1 deletion strain in which the PKA pathway was constitutively active and the umpde1 deletion strains were significantly reduced in pathogenicity, while the umpde2 deletion strains showed a trend for reduced pathogenicity compared with wild-type strains. These data support a role for the phosphodiesterases UmPde1 and UmPde2 in regulating the U. maydis cAMP-dependent PKA pathway through modulation of cAMP levels, thus affecting dimorphic growth and pathogenicity.
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Affiliation(s)
- Charu Agarwal
- Department of Biology, Program on Disease Evolution, University of Louisville, Louisville, KY 40208, USA
| | - Kavita B Aulakh
- Department of Biology, Program on Disease Evolution, University of Louisville, Louisville, KY 40208, USA
| | - Kaly Edelen
- Department of Biology, Program on Disease Evolution, University of Louisville, Louisville, KY 40208, USA
| | - Michael Cooper
- Department of Biology, Program on Disease Evolution, University of Louisville, Louisville, KY 40208, USA
| | - R Margaret Wallen
- Department of Biology, Program on Disease Evolution, University of Louisville, Louisville, KY 40208, USA
| | - Seth Adams
- Department of Biology, Program on Disease Evolution, University of Louisville, Louisville, KY 40208, USA
| | - David J Schultz
- Department of Biology, Program on Disease Evolution, University of Louisville, Louisville, KY 40208, USA
| | - Michael H Perlin
- Department of Biology, Program on Disease Evolution, University of Louisville, Louisville, KY 40208, USA
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31
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Horst RJ, Zeh C, Saur A, Sonnewald S, Sonnewald U, Voll LM. The Ustilago maydis Nit2 homolog regulates nitrogen utilization and is required for efficient induction of filamentous growth. EUKARYOTIC CELL 2012; 11:368-80. [PMID: 22247264 PMCID: PMC3294441 DOI: 10.1128/ec.05191-11] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Accepted: 12/22/2011] [Indexed: 11/20/2022]
Abstract
Nitrogen catabolite repression (NCR) is a regulatory strategy found in microorganisms that restricts the utilization of complex and unfavored nitrogen sources in the presence of favored nitrogen sources. In fungi, this concept has been best studied in yeasts and filamentous ascomycetes, where the GATA transcription factors Gln3p and Gat1p (in yeasts) and Nit2/AreA (in ascomycetes) constitute the main positive regulators of NCR. The reason why functional Nit2 homologs of some phytopathogenic fungi are required for full virulence in their hosts has remained elusive. We have identified the Nit2 homolog in the basidiomycetous phytopathogen Ustilago maydis and show that it is a major, but not the exclusive, positive regulator of nitrogen utilization. By transcriptome analysis of sporidia grown on artificial media devoid of favored nitrogen sources, we show that only a subset of nitrogen-responsive genes are regulated by Nit2, including the Gal4-like transcription factor Ton1 (a target of Nit2). Ustilagic acid biosynthesis is not under the control of Nit2, while nitrogen starvation-induced filamentous growth is largely dependent on functional Nit2. nit2 deletion mutants show the delayed initiation of filamentous growth on maize leaves and exhibit strongly compromised virulence, demonstrating that Nit2 is required to efficiently initiate the pathogenicity program of U. maydis.
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Affiliation(s)
- Robin J Horst
- Division of Biochemistry, Friedrich-Alexander-University Erlangen-Nuremberg, Staudtstr. 5, Erlangen, Germany
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32
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Abstract
Why mating types exist at all is subject to much debate. Among hypotheses, mating types evolved to control organelle transmission during sexual reproduction, or to prevent inbreeding or same-clone mating. Here I review data from a diversity of taxa (including ciliates, algae, slime molds, ascomycetes, and basidiomycetes) to show that the structure and function of mating types run counter the above hypotheses. I argue instead for a key role in triggering developmental switches. Genomes must fulfill a diversity of alternative programs along the sexual cycle. As a haploid gametophyte, an individual may grow vegetatively (through haploid mitoses), or initiate gametogenesis and mating. As a diploid sporophyte, similarly, it may grow vegetatively (through diploid mitoses) or initiate meiosis and sporulation. Only diploid sporophytes (and not haploid gametophytes) should switch on the meiotic program. Similarly, only haploid gametophytes (not sporophytes) should switch on gametogenesis and mating. And they should only do so when other gametophytes are ready to do the same in the neighborhood. As argued here, mating types have evolved primarily to switch on the right program at the right moment.
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Affiliation(s)
- Nicolas Perrin
- Department of Ecology & Evolution, University of Lausanne, Lausanne, Switzerland.
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33
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Wang L, Berndt P, Xia X, Kahnt J, Kahmann R. A seven-WD40 protein related to human RACK1 regulates mating and virulence in Ustilago maydis. Mol Microbiol 2011; 81:1484-98. [PMID: 21815950 DOI: 10.1111/j.1365-2958.2011.07783.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
In mammalian cells RACK1 serves as a scaffold protein that has a role in integrating inputs from different signalling pathways and affects translation through association with ribosomes. Ustilago maydis contains a seven-WD40 repeat motif protein designated Rak1, which shows 68% identity to RACK1 and 51% identity to Asc1p of Saccharomyces cerevisiae. An asc1 mutant could be complemented by introduction of U. maydis rak1. The deletion of rak1 affected cell growth, cell wall integrity and specifically attenuated cell fusion. This latter defect was caused by reduced expression of prf1 encoding the regulator for pheromone (mfa) and pheromone-receptor genes. Rak1 interacts with a variety of ribosomal proteins and microarray analysis revealed that the deletion of rak1 led to severely reduced expression of rop1, a transcriptional activator of prf1. The constitutive expression of rop1 could rescue the defect of mfa1 expression as well as conjugation tube formation in response to pheromone induction in the rak1 mutant. Moreover, a solopathogenic rak1 mutant failed to respond to plant-derived stimuli, resulting in attenuated filamentation and pathogenicity. This could be partially rescued by constitutive expression of the b heterodimer. These data suggest that rak1 is a regulator of rop1 expression with additional roles after cell fusion.
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Affiliation(s)
- Lei Wang
- Max Planck Institute for Terrestrial Microbiology, Karl-von-Frisch-Strasse 10, D-35043 Marburg, Germany
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Vollmeister E, Schipper K, Baumann S, Haag C, Pohlmann T, Stock J, Feldbrügge M. Fungal development of the plant pathogen Ustilago maydis. FEMS Microbiol Rev 2011; 36:59-77. [PMID: 21729109 DOI: 10.1111/j.1574-6976.2011.00296.x] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The maize pathogen Ustilago maydis has to undergo various morphological transitions for the completion of its sexual life cycle. For example, haploid cells respond to pheromone by forming conjugation tubes that fuse at their tips. The resulting dikaryon grows filamentously, expanding rapidly at the apex and inserting retraction septa at the basal pole. In this review, we present progress on the underlying mechanisms regulating such defined developmental programmes. The key findings of the postgenomic era are as follows: (1) endosomes function not only during receptor recycling, but also as multifunctional transport platforms; (2) a new transcriptional master regulator for pathogenicity is part of an intricate transcriptional network; (3) determinants for uniparental mitochondrial inheritance are encoded at the a2 mating-type locus; (4) microtubule-dependent mRNA transport is important in determining the axis of polarity; and (5) a battery of fungal effectors encoded in gene clusters is crucial for plant infection. Importantly, most processes are tightly controlled at the transcriptional, post-transcriptional and post-translational levels, resulting in a complex regulatory network. This intricate system is crucial for the timing of the correct order of developmental phases. Thus, new insights from all layers of regulation have substantially advanced our understanding of fungal development.
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Affiliation(s)
- Evelyn Vollmeister
- Institute for Microbiology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
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35
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Frieser SH, Hlubek A, Sandrock B, Bölker M. Cla4 kinase triggers destruction of the Rac1-GEF Cdc24 during polarized growth in Ustilago maydis. Mol Biol Cell 2011; 22:3253-62. [PMID: 21757543 PMCID: PMC3164470 DOI: 10.1091/mbc.e11-04-0314] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
In the dimorphic fungus Ustilago maydis, Rac1 and its activator Cdc24 are essential for hyphal tip growth. Rac1 is shown to stimulate Cla4 kinase, which in turn triggers destruction of Cdc24. Expression of stabilized Cdc24 interferes with cell polarization, indicating that negative feedback regulation of Cdc24 is critical for tip growth. Dimorphic switching from budding to filamentous growth is a characteristic feature of many pathogenic fungi. In the fungal model organism Ustilago maydis polarized growth is induced by the multiallelic b mating type locus and requires the Rho family GTPase Rac1. Here we show that mating type–induced polarized growth involves negative feedback regulation of the Rac1-specific guanine nucleotide exchange factor (GEF) Cdc24. Although Cdc24 is essential for polarized growth, its concentration is drastically diminished during filament formation. Cdc24 is part of a protein complex that also contains the scaffold protein Bem1 and the PAK kinase Cla4. Activation of Rac1 results in Cla4-dependent degradation of the Rac1-GEF Cdc24, thus creating a regulatory negative feedback loop. We generated mutants of Cdc24 that are resistant to Cla4-dependent destruction. Expression of stable Cdc24 variants interfered with filament formation, indicating that negative feedback regulation of Cdc24 is critical for the establishment of polarized growth.
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36
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de Sena-Tomás C, Fernández-Álvarez A, Holloman WK, Pérez-Martín J. The DNA damage response signaling cascade regulates proliferation of the phytopathogenic fungus Ustilago maydis in planta. THE PLANT CELL 2011; 23:1654-65. [PMID: 21478441 PMCID: PMC3101559 DOI: 10.1105/tpc.110.082552] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
In the phytopathogenic fungus Ustilago maydis, the dikaryotic state dominates the period of growth occurring during the infectious phase. Dikaryons are cells in which two nuclei, one from each parent cell, share a single cytoplasm for a period of time without undergoing nuclear fusion. In fungal cells, maintenance of the dikaryotic state requires an intricate cell division process that often involves the formation of a structure known as the clamp connection as well as the sorting of one of the nuclei to this structure to ensure that each daughter dikaryon inherits a balance of each parental genome. Here, we describe an atypical role of the DNA damage checkpoint kinases Chk1 and Atr1 during pathogenic growth of U. maydis. We found that Chk1 and Atr1 collaborate to control cell cycle arrest during the induction of the virulence program in U. maydis and that Chk1 and Atr1 work together to control the dikaryon formation. These findings uncover a link between a widely conserved signaling cascade and the virulence program in a phytopathogen. We propose a model in which adjustment of the cell cycle by the Atr1-Chk1 axis controls fidelity in dikaryon formation. Therefore, Chk1 and Atr1 emerge as critical cell type regulators in addition to their roles in the DNA damage response.
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Affiliation(s)
- Carmen de Sena-Tomás
- Departamento de Biotecnología Microbiana, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain
| | - Alfonso Fernández-Álvarez
- Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide, Consejo Superior de Investigaciones Científicas, 41013 Sevilla, Spain
| | - William K. Holloman
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, New York 10065
| | - José Pérez-Martín
- Departamento de Biotecnología Microbiana, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain
- Address correspondence to
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Rubini A, Belfiori B, Riccioni C, Tisserant E, Arcioni S, Martin F, Paolocci F. Isolation and characterization of MAT genes in the symbiotic ascomycete Tuber melanosporum. THE NEW PHYTOLOGIST 2011; 189:710-722. [PMID: 20961294 DOI: 10.1111/j.1469-8137.2010.03492.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
• The genome of Tuber melanosporum has recently been sequenced. Here, we used this information to identify genes involved in the reproductive processes of this edible fungus. The sequenced strain (Mel28) possesses only one of the two master genes required for mating, that is, the gene that codes for the high mobility group (HMG) transcription factor (MAT1-2-1), whereas it lacks the gene that codes for the protein containing the α-box- domain (MAT1-1-1), suggesting that this fungus is heterothallic. • A PCR-based approach was initially employed to screen truffles for the presence of the MAT1-2-1 gene and amplify the conserved regions flanking the mating type (MAT) locus. The MAT1-1-1 gene was finally identified using primers designed from the conserved regions of strains that lack the MAT1-2-1 gene. • Mating type-specific primer pairs were developed to screen asci and gleba from truffles of different origins and to genotype single ascospores within the asci. These analyses provided definitive evidence that T. melanosporum is a heterothallic species with a MAT locus that is organized similarly to those of ancient fungal lineages. • A greater understanding of the reproductive mechanisms that exist in Tuber spp. allows for optimization of truffle plantation management strategies.
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Affiliation(s)
- Andrea Rubini
- National Research Council, Plant Genetics Institute - Perugia Division, Via della Madonna Alta 130, I-06128 Perugia, Italy
| | - Beatrice Belfiori
- National Research Council, Plant Genetics Institute - Perugia Division, Via della Madonna Alta 130, I-06128 Perugia, Italy
| | - Claudia Riccioni
- National Research Council, Plant Genetics Institute - Perugia Division, Via della Madonna Alta 130, I-06128 Perugia, Italy
| | - Emilie Tisserant
- UMR 1136, Interactions Arbres/Microorganismes, INRA-Nancy, F-54280 Champenoux, France
| | - Sergio Arcioni
- National Research Council, Plant Genetics Institute - Perugia Division, Via della Madonna Alta 130, I-06128 Perugia, Italy
| | - Francis Martin
- UMR 1136, Interactions Arbres/Microorganismes, INRA-Nancy, F-54280 Champenoux, France
| | - Francesco Paolocci
- National Research Council, Plant Genetics Institute - Perugia Division, Via della Madonna Alta 130, I-06128 Perugia, Italy
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38
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Kruzel EK, Hull CM. Establishing an unusual cell type: how to make a dikaryon. Curr Opin Microbiol 2010; 13:706-11. [PMID: 21036099 DOI: 10.1016/j.mib.2010.09.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2010] [Revised: 09/25/2010] [Accepted: 09/28/2010] [Indexed: 12/19/2022]
Abstract
The dikaryons of basidiomycete fungi represent an unusual cell type required for complete sexual development. Dikaryon formation occurs via the activities of cell type-specific homeodomain transcription factors, which form regulatory complexes to establish the dikaryotic state. Decades of classical genetic and cell biological studies in mushrooms have provided a foundation for more recent molecular studies in the pathogenic species Ustilago maydis and Cryptococcus neoformans. Studies in these systems have revealed novel mechanisms of regulation that function downstream of classic homeodomain complexes to ensure that dikaryons are established and propagated. Comparisons of these dikaryon-specific networks promise to reveal the nature of regulatory network evolution and the adaptations responsible for driving complex eukaryotic development.
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Affiliation(s)
- Emilia K Kruzel
- Department of Biomolecular Chemistry, University of Wisconsin, School of Medicine and Public Health, Madison, WI 53706, United States
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39
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Zahiri A, Heimel K, Wahl R, Rath M, Kämper J. The Ustilago maydis forkhead transcription factor Fox1 is involved in the regulation of genes required for the attenuation of plant defenses during pathogenic development. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2010; 23:1118-29. [PMID: 20687802 DOI: 10.1094/mpmi-23-9-1118] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Ustilago maydis is a plant-pathogenic fungus that establishes a biotrophic relationship with its host plant, Zea mays. The pathogenic stage of U. maydis is initiated by the fusion of two haploid cells, resulting in the formation of a dikaryotic hypha that invades the plant cell. The switch from saprophytic, yeast-like cells to the biotrophic hyphae requires the complex regulation of a multitude of biological processes to constitute the compatible host-fungus interaction. Transcriptional regulators involved in the establishment of the infectious dikaryon and penetration of the host tissue have been identified; however, regulators required during the post-penetration stages remained to be elucidated. In this study, we report the identification of a U. maydis forkhead transcription factor, Fox1, which is exclusively expressed during biotrophic development. Deletion of fox1 results in reduced virulence and impaired tumor development. The Deltafox1 hyphae induce the accumulation of H(2)O(2) in and around infected cells and a maize defense response phenotypically represented by the encasement of proliferating hyphae in a cellulose-containing matrix. The phenotype can be attributed to the fox1-dependent deregulation of several effector genes that are linked to pathogenic development and host defense suppression.
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Affiliation(s)
- Alexander Zahiri
- Karlsruhe Institute of Technology, Institute for Applied Biosciences, Department of Genetics, D-76187 Karlsruhe, Germany
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40
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Heimel K, Scherer M, Schuler D, Kämper J. The Ustilago maydis Clp1 protein orchestrates pheromone and b-dependent signaling pathways to coordinate the cell cycle and pathogenic development. THE PLANT CELL 2010; 22:2908-22. [PMID: 20729384 PMCID: PMC2947178 DOI: 10.1105/tpc.110.076265] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2010] [Revised: 07/30/2010] [Accepted: 08/05/2010] [Indexed: 05/19/2023]
Abstract
Regulation of the cell cycle and morphogenetic switching during pathogenic and sexual development in Ustilago maydis is orchestrated by a concerted action of the a and b mating-type loci. Activation of either mating-type locus triggers the G2 cell cycle arrest that is a prerequisite for the formation of the infectious dikaryon; this cell cycle arrest is released only after penetration of the host plant. Here, we show that bW, one of the two homeodomain transcription factors encoded by the b mating-type locus, and the zinc-finger transcription factor Rbf1, a master regulator for pathogenic development, interact with Clp1 (clampless 1), a protein required for the distribution of nuclei during cell division of the dikaryon. In addition, we identify Cib1, a previously undiscovered bZIP transcription factor required for pathogenic development, as a Clp1-interacting protein. Clp1 interaction with bW blocks b-dependent functions, such as the b-dependent G2 cell cycle arrest and dimorphic switching. The interaction of Clp1 with Rbf1 results in the repression of the a-dependent pheromone pathway, conjugation tube formation, and the a-induced G2 cell cycle arrest. The concerted interaction of Clp1 with Rbf1 and bW coordinates a- and b-dependent cell cycle control and ensures cell cycle release and progression at the onset of biotrophic development.
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Affiliation(s)
- Kai Heimel
- Department of Genetics, Karlsruhe Institute of Technology, 76187 Karlsruhe, Germany
- Max-Planck Institute for Terrestrial Microbiology, 35043 Marburg, Germany
| | - Mario Scherer
- Max-Planck Institute for Terrestrial Microbiology, 35043 Marburg, Germany
| | - David Schuler
- Department of Genetics, Karlsruhe Institute of Technology, 76187 Karlsruhe, Germany
| | - Jörg Kämper
- Department of Genetics, Karlsruhe Institute of Technology, 76187 Karlsruhe, Germany
- Max-Planck Institute for Terrestrial Microbiology, 35043 Marburg, Germany
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41
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Fernández-Alvarez A, Elías-Villalobos A, Ibeas JI. Protein glycosylation in the phytopathogen Ustilago maydis: From core oligosaccharide synthesis to the ER glycoprotein quality control system, a genomic analysis. Fungal Genet Biol 2010; 47:727-35. [PMID: 20554055 DOI: 10.1016/j.fgb.2010.06.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2010] [Revised: 05/28/2010] [Accepted: 06/01/2010] [Indexed: 01/21/2023]
Abstract
The corn smut fungus Ustilago maydis has, over recent decades, become established as a robust pathogenic model for studying fungi-plant relationships. This use of U. maydis can be attributed to its biotrophic host interaction, easy culture and genetic manipulation in the laboratory, and the severe disease symptoms it induces in infected maize. Recent studies have shown that normal protein glycosylation is essential for pathogenic development, but dispensable for the saprophytic growth or mating. Given the relevance of protein glycosylation for U. maydis virulence, and consequently its role in the plant pathogenesis, here we review the main actors and events implicated in protein glycosylation. Furthermore, we describe the results of an in silico search, where we identify all the conserved members of the N- and O-glycosylation pathways in U. maydis at each stage: core oligosaccharide synthesis, addition of the core oligosaccharide to nascent target proteins, maturation and extension of the core oligosaccharide, and the quality control system used by the cell to avoid the presence of unfolded glycoproteins. Finally, we discuss how these genes could affect U. maydis virulence and their biotechnological implications.
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Affiliation(s)
- Alfonso Fernández-Alvarez
- Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide - Consejo Superior de Investigaciones Científicas, Seville, Spain
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42
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Lee SC, Ni M, Li W, Shertz C, Heitman J. The evolution of sex: a perspective from the fungal kingdom. Microbiol Mol Biol Rev 2010; 74:298-340. [PMID: 20508251 PMCID: PMC2884414 DOI: 10.1128/mmbr.00005-10] [Citation(s) in RCA: 243] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Sex is shrouded in mystery. Not only does it preferentially occur in the dark for both fungi and many animals, but evolutionary biologists continue to debate its benefits given costs in light of its pervasive nature. Experimental studies of the benefits and costs of sexual reproduction with fungi as model systems have begun to provide evidence that the balance between sexual and asexual reproduction shifts in response to selective pressures. Given their unique evolutionary history as opisthokonts, along with metazoans, fungi serve as exceptional models for the evolution of sex and sex-determining regions of the genome (the mating type locus) and for transitions that commonly occur between outcrossing/self-sterile and inbreeding/self-fertile modes of reproduction. We review here the state of the understanding of sex and its evolution in the fungal kingdom and also areas where the field has contributed and will continue to contribute to illuminating general principles and paradigms of sexual reproduction.
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Affiliation(s)
- Soo Chan Lee
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina 27710
| | - Min Ni
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina 27710
| | - Wenjun Li
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina 27710
| | - Cecelia Shertz
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina 27710
| | - Joseph Heitman
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina 27710
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