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Kappel L, Yu L, Escobar C, Marcianò D, Srivastava V, Bulone V, Gruber S. A comparative cell wall analysis of Trichoderma spp. confirms a conserved polysaccharide scaffold and suggests an important role for chitosan in mycoparasitism. Microbiol Spectr 2024; 12:e0349523. [PMID: 38916333 PMCID: PMC11302013 DOI: 10.1128/spectrum.03495-23] [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: 11/15/2023] [Accepted: 05/14/2024] [Indexed: 06/26/2024] Open
Abstract
Fungal cell walls are dynamic extracellular matrices that enable efficient adaptation to changing environments. While the cell wall compositions of yeasts, human, and plant pathogenic fungi have been studied to some extent, the cell walls of mycoparasites remain poorly characterized. Trichoderma species comprise a diverse group of soil fungi with different survival strategies and lifestyles. The comparative study of cell wall carbohydrate-active enzymes in 13 Trichoderma spp. revealed that the types of enzymes involved in chitin and chitosan metabolism are phylogenetically distant between mycoparasitic and saprotrophic species. Here, we compare the carbohydrate composition and function of the cell wall of a saprotrophic strain Trichoderma reesei with that of the mycoparasitic, biological control agent Trichoderma atroviride. Monosaccharide and glycosidic linkage analyses as well as dual in situ interaction assays showed that the cell wall polysaccharide composition is conserved between both species, except for the amounts of chitin detected. The results suggest that the observed accumulation of chitosan during mycoparasitism may prevent host recognition. Remarkably, Trichoderma atroviride undergoes dynamic cell wall adaptations during both vegetative development and mycoparasitism, which appears to be confirmed by an evolutionarily expanded group of specialized enzymes. Overall, our analyses support the notion that habitat specialization is reflected in cell wall architecture and that plastic chitin remodeling may confer an advantage to mycoparasites, ultimately enabling the successful invasion and parasitism of plant pathogens. This information may potentially be exploited for the control of crop diseases using biological agents. IMPORTANCE Trichoderma species are emerging model fungi for the development of biocontrol agents and are used in industrial biotechnology as efficient enzyme producers. Fungal cell walls are complex structures that differ in carbohydrate, protein, and enzyme composition across taxa. Here, we present a chemical characterization of the cell walls of two Trichoderma spp., namely the predominantly saprotrophic Trichoderma reesei and the mycoparasite Trichoderma atroviride. Chemical profiling revealed that Trichoderma spp. remodel their cell wall to adapt to particular lifestyles, with dynamic changes during vegetative development. Importantly, we found that chitosan accumulation during mycoparasitism of a fungal host emerged as a sophisticated strategy underpinning an effective attack. These insights shed light on the molecular mechanisms that allow mycoparasites to overcome host defenses and can be exploited to improve the application of T. atroviride in biological pest control. Moreover, our results provide valuable information for targeting the fungal cell wall for therapeutic purposes.
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Affiliation(s)
- Lisa Kappel
- Department of Bioengineering, University of Applied Sciences, Vienna, Austria
- Department of Microbiology, University of Innsbruck, Innsbruck, Austria
| | - Long Yu
- School of Agriculture, Food and Wine, The University of Adelaide, Adelaide, Australia
| | - Carolina Escobar
- Department of Bioengineering, University of Applied Sciences, Vienna, Austria
- Department of Microbiology, University of Innsbruck, Innsbruck, Austria
| | - Demetrio Marcianò
- Department of Agricultural and Environmental Sciences, via Celoria 2, Milan, Italy
| | - Vaibhav Srivastava
- Division of Glycoscience, Department of Chemistry, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, AlbaNova University Centre, Stockholm, Sweden
| | - Vincent Bulone
- School of Agriculture, Food and Wine, The University of Adelaide, Adelaide, Australia
- Division of Glycoscience, Department of Chemistry, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, AlbaNova University Centre, Stockholm, Sweden
| | - Sabine Gruber
- Department of Bioengineering, University of Applied Sciences, Vienna, Austria
- Department of Microbiology, University of Innsbruck, Innsbruck, Austria
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Rij M, Kayacan Y, Bernardi B, Wendland J. Re-routing MAP kinase signaling for penetration peg formation in predator yeasts. PLoS Pathog 2024; 20:e1012503. [PMID: 39213444 PMCID: PMC11392346 DOI: 10.1371/journal.ppat.1012503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2024] [Revised: 09/12/2024] [Accepted: 08/14/2024] [Indexed: 09/04/2024] Open
Abstract
Saccharomycopsis yeasts are natural organic sulfur auxotrophs due to lack of genes required for the uptake and assimilation of sulfate/sulfite. Starvation for methionine induces a shift to a predatory, mycoparasitic life strategy that is unique amongst ascomycetous yeasts. Similar to fungal plant pathogens that separated from Saccharomycopsis more than 400 million years ago, a specialized infection structure called penetration peg is used for prey cell invasion. Penetration pegs are highly enriched with chitin. Here we demonstrate that an ancient and conserved MAP kinase signaling pathway regulates penetration peg formation and successful predation in the predator yeast S. schoenii. Deletion of the MAP kinase gene SsKIL1, a homolog of the Saccharomyces cerevisiae ScKSS1/ScFUS3 and the rice blast Magnaporthe oryzae MoPMK1 genes, as well as deletion of the transcription factor SsSTE12 generate non-pathogenic mutants that fail to form penetration pegs. Comparative global transcriptome analyses using RNAseq indicate loss of the SsKil1-SsSte12-dependent predation response in the mutant strains, while a methionine starvation response is still executed. Within the promoter sequences of genes upregulated during predation we identified a cis-regulatory element similar to the ScSte12 pheromone response element. Our results indicate that, re-routing MAP-kinase signaling by re-wiring Ste12 transcriptional control towards predation specific genes contributed to the parallel evolution of this predacious behaviour in predator yeasts. Consequently, we found that SsSTE12 is dispensable for mating.
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Affiliation(s)
- Mareike Rij
- Department of Microbiology and Biochemistry, Hochschule Geisenheim University, Geisenheim, Germany
| | - Yeseren Kayacan
- Research Group of Microbiology (MICR)-Functional Yeast Genomics, Vrije Universiteit Brussel, Brussels, Belgium
| | - Beatrice Bernardi
- Department of Microbiology and Biochemistry, Hochschule Geisenheim University, Geisenheim, Germany
- Research Group of Microbiology (MICR)-Functional Yeast Genomics, Vrije Universiteit Brussel, Brussels, Belgium
| | - Jürgen Wendland
- Department of Microbiology and Biochemistry, Hochschule Geisenheim University, Geisenheim, Germany
- Research Group of Microbiology (MICR)-Functional Yeast Genomics, Vrije Universiteit Brussel, Brussels, Belgium
- Geisenheim Yeast Breeding Center, Hochschule Geisenheim University, Geisenheim, Germany
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Schalamun M, Hinterdobler W, Schinnerl J, Brecker L, Schmoll M. The transcription factor STE12 influences growth on several carbon sources and production of dehydroacetic acid (DHAA) in Trichoderma reesei. Sci Rep 2024; 14:9625. [PMID: 38671155 PMCID: PMC11053031 DOI: 10.1038/s41598-024-59511-8] [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: 01/07/2024] [Accepted: 04/11/2024] [Indexed: 04/28/2024] Open
Abstract
The filamentous ascomycete Trichoderma reesei, known for its prolific cellulolytic enzyme production, recently also gained attention for its secondary metabolite synthesis. Both processes are intricately influenced by environmental factors like carbon source availability and light exposure. Here, we explore the role of the transcription factor STE12 in regulating metabolic pathways in T. reesei in terms of gene regulation, carbon source utilization and biosynthesis of secondary metabolites. We show that STE12 is involved in regulating cellulase gene expression and growth on carbon sources associated with iron homeostasis. STE12 impacts gene regulation in a light dependent manner on cellulose with modulation of several CAZyme encoding genes as well as genes involved in secondary metabolism. STE12 selectively influences the biosynthesis of the sorbicillinoid trichodimerol, while not affecting the biosynthesis of bisorbibutenolide, which was recently shown to be regulated by the MAPkinase pathway upstream of STE12 in the signaling cascade. We further report on the biosynthesis of dehydroacetic acid (DHAA) in T. reesei, a compound known for its antimicrobial properties, which is subject to regulation by STE12. We conclude, that STE12 exerts functions beyond development and hence contributes to balance the energy distribution between substrate consumption, reproduction and defense.
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Affiliation(s)
- Miriam Schalamun
- AIT Austrian Institute of Technology GmbH, Center for Health and Bioresources, Konrad Lorenz Strasse 24, 3430, Tulln, Austria
| | - Wolfgang Hinterdobler
- AIT Austrian Institute of Technology GmbH, Center for Health and Bioresources, Konrad Lorenz Strasse 24, 3430, Tulln, Austria
- MyPilz GmbH, Wienerbergstrasse 55/13-15, 1120, Vienna, Austria
| | - Johann Schinnerl
- Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, 1030, Vienna, Austria
| | - Lothar Brecker
- Department of Organic Chemistry, University of Vienna, Währinger Strasse 38, 1090, Vienna, Austria
| | - Monika Schmoll
- AIT Austrian Institute of Technology GmbH, Center for Health and Bioresources, Konrad Lorenz Strasse 24, 3430, Tulln, Austria.
- Division of Terrestrial Ecosystem Research, Department of Microbiology and Ecosystem Science, University of Vienna, Djerassiplatz 1, 1030, Vienna, Austria.
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Speckbacher V, Flatschacher D, Martini-Lösch N, Ulbrich L, Baldin C, Bauer I, Ruzsanyi V, Zeilinger S. The histone deacetylase Hda1 affects oxidative and osmotic stress response as well as mycoparasitic activity and secondary metabolite biosynthesis in Trichoderma atroviride. Microbiol Spectr 2024; 12:e0309723. [PMID: 38334386 PMCID: PMC10913545 DOI: 10.1128/spectrum.03097-23] [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: 08/14/2023] [Accepted: 01/10/2024] [Indexed: 02/10/2024] Open
Abstract
The mycoparasitic fungus Trichoderma atroviride is applied in agriculture as a biostimulant and biologic control agent against fungal pathogens that infest crop plants. Secondary metabolites are among the main agents determining the strength and progress of the mycoparasitic attack. However, expression of most secondary metabolism-associated genes requires specific cues, as they are silent under routine laboratory conditions due to their maintenance in an inactive heterochromatin state. Therefore, histone modifications are crucial for the regulation of secondary metabolism. Here, we functionally investigated the role of the class II histone deacetylase encoding gene hda1 of T. atroviride by targeted gene deletion, phenotypic characterization, and multi-omics approaches. Deletion of hda1 did not result in obvious phenotypic alterations but led to an enhanced inhibitory activity of secreted metabolites and reduced mycoparasitic abilities of T. atroviride against the plant-pathogenic fungi Botrytis cinerea and Rhizoctonia solani. The ∆hda1 mutants emitted altered amounts of four volatile organic compounds along their development, produced different metabolite profiles upon growth in liquid culture, and showed a higher susceptibility to oxidative and osmotic stress. Moreover, hda1 deletion affected the expression of several notable gene categories such as polyketide synthases, transcription factors, and genes involved in the HOG MAPK pathway.IMPORTANCEHistone deacetylases play crucial roles in regulating chromatin structure and gene transcription. To date, classical-Zn2+ dependent-fungal histone deacetylases are divided into two classes, of which each comprises orthologues of the two sub-groups Rpd3 and Hos2 and Hda1 and Hos3 of yeast, respectively. However, the role of these chromatin remodelers in mycoparasitic fungi is poorly understood. In this study, we provide evidence that Hda1, the class II histone deacetylases of the mycoparasitic fungus Trichoderma atroviride, regulates its mycoparasitic activity, secondary metabolite biosynthesis, and osmotic and oxidative stress tolerance. The function of Hda1 in regulating bioactive metabolite production and mycoparasitism reveals the importance of chromatin-dependent regulation in the ability of T. atroviride to successfully control fungal plant pathogens.
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Affiliation(s)
| | | | | | - Laura Ulbrich
- Umweltmonitoring und Forensische Chemie, Hochschule Hamm-Lippstadt, Hamm, Germany
| | - Clara Baldin
- Department of Microbiology, Universität Innsbruck, Innsbruck, Austria
| | - Ingo Bauer
- Institute of Molecular Biology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
| | | | - Susanne Zeilinger
- Department of Microbiology, Universität Innsbruck, Innsbruck, Austria
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5
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Atanasova L, Marchetti-Deschmann M, Nemes A, Bruckner B, Rehulka P, Stralis-Pavese N, Łabaj PP, Kreil DP, Zeilinger S. Mycoparasitism related targets of Tmk1 indicate stimulating regulatory functions of this MAP kinase in Trichoderma atroviride. Sci Rep 2023; 13:19976. [PMID: 37968441 PMCID: PMC10651915 DOI: 10.1038/s41598-023-47027-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 11/08/2023] [Indexed: 11/17/2023] Open
Abstract
Mycoparasitism is a key feature of Trichoderma (Hypocreales, Ascomycota) biocontrol agents. Recent studies of intracellular signal transduction pathways of the potent mycoparasite Trichoderma atroviride revealed the involvement of Tmk1, a mitogen-activated protein kinase (MAPK), in triggering the mycoparasitic response. We previously showed that mutants missing Tmk1 exhibit reduced mycoparasitic activity against several plant pathogenic fungi. In this study, we identified the most robustly regulated targets that were governed by Tmk1 during mycoparasitism using transcriptome and proteome profiling. Tmk1 mainly exerts a stimulating function for T. atroviride during its mycoparasitic interaction with the fungal plant pathogen Rhizoctonia solani, as reflected by 89% of strongly differently responding genes in the ∆tmk1 mutant compared to the wild type. Specifically, 54% of these genes showed strong downregulation in the response with a deletion of the tmk1 gene, whereas in the wild type the same genes were strongly upregulated during the interaction with the fungal host. These included the gene encoding the mycoparasitism-related proteinase Prb1; genes involved in signal transduction pathways such as a candidate coding for a conserved 14-3-3 protein, and a gene coding for Tmk2, the T. atroviride cell-wall integrity MAP kinase; genes encoding a specific siderophore synthetase, and multiple FAD-dependent oxidoreductases and aminotransferases. Due to the phosphorylating activity of Tmk1, different (phospho-)proteomics approaches were applied and identified proteins associated with cellular metabolism, energy production, protein synthesis and fate, and cell organization. Members of FAD- and NAD/NADP-binding-domain proteins, vesicular trafficking of molecules between cellular organelles, fungal translational, as well as protein folding apparatus were among others found to be phosphorylated by Tmk1 during mycoparasitism. Outstanding downregulation in the response of the ∆tmk1 mutant to the fungal host compared to the wild type at both the transcriptome and the proteome levels was observed for nitrilase, indicating that its defense and detoxification functions might be greatly dependent on Tmk1 during T. atroviride mycoparasitism. An intersection network analysis between the identified transcripts and proteins revealed a strong involvement of Tmk1 in molecular functions with GTPase and oxidoreductase activity. These data suggest that during T. atroviride mycoparasitism this MAPK mainly governs processes regulating cell responses to extracellular signals and those involved in reactive oxygen stress.
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Affiliation(s)
- Lea Atanasova
- Department of Food Science and Technology, University of Natural Resources and Life Sciences Vienna (BOKU), Vienna, Austria.
- Department of Microbiology, Universität Innsbruck, Innsbruck, Austria.
| | - Martina Marchetti-Deschmann
- Institute of Chemical Technologies and Analytics, TU Wien (Vienna University of Technology), Vienna, Austria
| | - Albert Nemes
- Institute of Chemical Technologies and Analytics, TU Wien (Vienna University of Technology), Vienna, Austria
| | - Bianca Bruckner
- Institute of Chemical Technologies and Analytics, TU Wien (Vienna University of Technology), Vienna, Austria
| | - Pavel Rehulka
- Institute of Chemical Technologies and Analytics, TU Wien (Vienna University of Technology), Vienna, Austria
- Department of Molecular Pathology, Faculty of Military Health Sciences, University of Defence, Hradec Králové, Czech Republic
| | - Nancy Stralis-Pavese
- IMBT Bioinformatics, Department of Biotechnology, University of Natural Resources and Life Sciences Vienna (BOKU), Vienna, Austria
| | - Paweł P Łabaj
- IMBT Bioinformatics, Department of Biotechnology, University of Natural Resources and Life Sciences Vienna (BOKU), Vienna, Austria
| | - David P Kreil
- IMBT Bioinformatics, Department of Biotechnology, University of Natural Resources and Life Sciences Vienna (BOKU), Vienna, Austria.
| | - Susanne Zeilinger
- Department of Microbiology, Universität Innsbruck, Innsbruck, Austria.
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Tomah AA, Alamer ISA, Khattak AA, Ahmed T, Hatamleh AA, Al-Dosary MA, Ali HM, Wang D, Zhang J, Xu L, Li B. Potential of Trichoderma virens HZA14 in Controlling Verticillium Wilt Disease of Eggplant and Analysis of Its Genes Responsible for Microsclerotial Degradation. PLANTS (BASEL, SWITZERLAND) 2023; 12:3761. [PMID: 37960117 PMCID: PMC10649075 DOI: 10.3390/plants12213761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 10/25/2023] [Accepted: 10/31/2023] [Indexed: 11/15/2023]
Abstract
Verticillium dahliae is a soilborne fungal pathogen that causes vascular wilt diseases in a wide range of economically important crops, including eggplant. Trichoderma spp. are effective biological control agents that suppress a wide range of plant pathogens through a variety of mechanisms, including mycoparasitism. However, the molecular mechanisms of mycoparasitism of Trichoderma spp. in the degradation of microsclerotia of V. dahliae are not yet fully understood. In this study, the ability of 15 isolates of Trichoderma to degrade microsclerotia of V. dahliae was evaluated using a dual culture method. After 15 days, isolate HZA14 showed the greatest potential for microsclerotial degradation. The culture filtrate of isolate HZA14 also significantly inhibited the mycelial growth and conidia germination of V. dahliae at different dilutions. Moreover, this study showed that T. virens produced siderophores and indole-3-acetic acid (IAA). In disease control tests, T. virens HZA14 reduced disease severity in eggplant seedlings by up to 2.77%, resulting in a control efficacy of 96.59% at 30 days after inoculation. Additionally, inoculation with an HZA14 isolate increased stem and root length and fresh and dry weight, demonstrating plant growth promotion efficacy. To further investigate the mycoparasitism mechanism of T. virens HZA14, transcriptomics sequencing and real-time fluorescence quantitative PCR (RT-qPCR) were used to identify the differentially expressed genes (DEGs) of T. virens HZA14 at 3, 6, 9, 12, and 15 days of the interaction with microsclerotia of V. dahliae. In contrast to the control group, the mycoparasitic process of T. virens HZA14 exhibited differential gene expression, with 1197, 1758, 1936, and 1914 genes being up-regulated and 1191, 1963, 2050, and 2114 genes being down-regulated, respectively. Among these genes, enzymes associated with the degradation of microsclerotia, such as endochitinase A1, endochitinase 3, endo-1,3-beta-glucanase, alpha-N-acetylglucosaminidase, laccase-1, and peroxidase were predicted based on bioinformatics analysis. The RT-qPCR results confirmed the RNA-sequencing data, showing that the expression trend of the genes was consistent. These results provide important information for understanding molecular mechanisms of microsclerotial degradation and integrated management of Verticillium wilt in eggplant and other crops.
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Affiliation(s)
- Ali Athafah Tomah
- State Key Laboratory of Rice Biology and Breeding, Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (A.A.T.); (I.S.A.A.); (A.A.K.); (T.A.); (J.Z.)
- Plant Protection, College of Agriculture, University of Misan, Al-Amarah 62001, Maysan Province, Iraq
| | - Iman Sabah Abd Alamer
- State Key Laboratory of Rice Biology and Breeding, Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (A.A.T.); (I.S.A.A.); (A.A.K.); (T.A.); (J.Z.)
- Plant Protection, Agriculture Directorate, Al-Amarah 62001, Maysan Province, Iraq
| | - Arif Ali Khattak
- State Key Laboratory of Rice Biology and Breeding, Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (A.A.T.); (I.S.A.A.); (A.A.K.); (T.A.); (J.Z.)
| | - Temoor Ahmed
- State Key Laboratory of Rice Biology and Breeding, Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (A.A.T.); (I.S.A.A.); (A.A.K.); (T.A.); (J.Z.)
- Xianghu Laboratory, Hangzhou 311231, China
| | - Ashraf Atef Hatamleh
- Department of Botany and Microbiology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia; (A.A.H.); (M.A.A.-D.); (H.M.A.)
| | - Munirah Abdullah Al-Dosary
- Department of Botany and Microbiology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia; (A.A.H.); (M.A.A.-D.); (H.M.A.)
| | - Hayssam M. Ali
- Department of Botany and Microbiology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia; (A.A.H.); (M.A.A.-D.); (H.M.A.)
| | - Daoze Wang
- Hangzhou Rural Revitalization Service Center, Hangzhou 310058, China;
| | - Jingze Zhang
- State Key Laboratory of Rice Biology and Breeding, Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (A.A.T.); (I.S.A.A.); (A.A.K.); (T.A.); (J.Z.)
| | - Lihui Xu
- Institute of Eco-Environmental Protection, Shanghai Academy of Agricultural Sciences, Shanghai 201403, China
| | - Bin Li
- State Key Laboratory of Rice Biology and Breeding, Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (A.A.T.); (I.S.A.A.); (A.A.K.); (T.A.); (J.Z.)
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Lv B, Guo Y, Zhao X, Li S, Sun M. Glucose-6-phosphate 1-Epimerase CrGlu6 Contributes to Development and Biocontrol Efficiency in Clonostachys chloroleuca. J Fungi (Basel) 2023; 9:764. [PMID: 37504752 PMCID: PMC10381721 DOI: 10.3390/jof9070764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 07/15/2023] [Accepted: 07/17/2023] [Indexed: 07/29/2023] Open
Abstract
Clonostachys chloroleuca (formerly classified as C. rosea) is an important mycoparasite active against various plant fungal pathogens. Mitogen-activated protein kinase (MAPK) signaling pathways are vital in mycoparasitic interactions; they participate in responses to diverse stresses and mediate fungal development. In previous studies, the MAPK-encoding gene Crmapk has been proven to be involved in mycoparasitism and the biocontrol processes of C. chloroleuca, but its regulatory mechanisms remain unclear. Aldose 1-epimerases are key enzymes in filamentous fungi that generate energy for fungal growth and development. By protein-protein interaction assays, the glucose-6-phosphate 1-epimerase CrGlu6 was found to interact with Crmapk, and expression of the CrGlu6 gene was significantly upregulated when C. chloroleuca colonized Sclerotinia sclerotiorum sclerotia. Gene deletion and complementation analyses showed that CrGlu6 deficiency caused abnormal morphology of hyphae and cells, and greatly reduced conidiation. Moreover, deletion mutants presented much lower antifungal activities and mycoparasitic ability, and control efficiency against sclerotinia stem rot was markedly decreased. When the CrGlu6 gene was reinserted, all biological characteristics and biocontrol activities were recovered. These findings provide new insight into the mechanisms of glucose-6-phosphate 1-epimerase in mycoparasitism and help to further reveal the regulation of MAPK and its interacting proteins in the biocontrol of C. chloroleuca.
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Affiliation(s)
- Binna Lv
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Yan Guo
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Xue Zhao
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Shidong Li
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Manhong Sun
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
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Christopher M, Sreeja-Raju A, Abraham A, Gokhale DV, Pandey A, Sukumaran RK. Early cellular events and potential regulators of cellulase induction in Penicillium janthinellum NCIM 1366. Sci Rep 2023; 13:5057. [PMID: 36977777 PMCID: PMC10050438 DOI: 10.1038/s41598-023-32340-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 03/26/2023] [Indexed: 03/30/2023] Open
Abstract
Cellulase production by fungi is tightly regulated in response to environmental cues, and understanding this mechanism is a key pre-requisite in the efforts to improve cellulase secretion. Based on UniProt descriptions of secreted Carbohydrate Active enZymes (CAZymes), 13 proteins of the cellulase hyper-producer Penicillium janthinellum NCIM 1366 (PJ-1366) were annotated as cellulases- 4 cellobiohydrolases (CBH), 7 endoglucanases (EG) and 2 beta glucosidases (BGL). Cellulase, xylanase, BGL and peroxidase activities were higher for cultures grown on a combination of cellulose and wheat bran, while EG was stimulated by disaccharides. Docking studies indicated that the most abundant BGL- Bgl2- has different binding sites for the substrate cellobiose and the product glucose, which helps to alleviate feedback inhibition, probably accounting for the low level of glucose tolerance exhibited. Out of the 758 transcription factors (TFs) differentially expressed on cellulose induction, 13 TFs were identified whose binding site frequencies on the promoter regions of the cellulases positively correlated with their abundance in the secretome. Further, correlation analysis of the transcriptional response of these regulators and TF-binding sites on their promoters indicated that cellulase expression is possibly preceded by up-regulation of 12 TFs and down-regulation of 16 TFs, which cumulatively regulate transcription, translation, nutrient metabolism and stress response.
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Affiliation(s)
- Meera Christopher
- Biofuels and Biorefineries Section, Microbial Processes and Technology Division, CSIR- National Institute for Interdisciplinary Science and Technology, Industrial Estate P.O., Pappanamcode, Thiruvananthapuram, Kerala, 695019, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad- 201002, India
| | - AthiraRaj Sreeja-Raju
- Biofuels and Biorefineries Section, Microbial Processes and Technology Division, CSIR- National Institute for Interdisciplinary Science and Technology, Industrial Estate P.O., Pappanamcode, Thiruvananthapuram, Kerala, 695019, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad- 201002, India
| | - Amith Abraham
- Department of Chemical Engineering, Hanyang University, Seoul, Republic of Korea
| | | | - Ashok Pandey
- Centre for Innovation and Translational Research, CSIR-Indian Institute of Toxicology Research, Lucknow, 226 001, Uttar Pradesh, India
- Sustainability Cluster, School of Engineering, University of Petroleum and Energy Studies, Dehradun, 248 007, India
- Centre for Energy and Environmental Sustainability, Lucknow, 226 029, India
| | - Rajeev K Sukumaran
- Biofuels and Biorefineries Section, Microbial Processes and Technology Division, CSIR- National Institute for Interdisciplinary Science and Technology, Industrial Estate P.O., Pappanamcode, Thiruvananthapuram, Kerala, 695019, India.
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad- 201002, India.
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Bai N, Xie M, Liu Q, Wang W, Liu Y, Yang J. AoSte12 Is Required for Mycelial Development, Conidiation, Trap Morphogenesis, and Secondary Metabolism by Regulating Hyphal Fusion in Nematode-Trapping Fungus Arthrobotrys oligospora. Microbiol Spectr 2023; 11:e0395722. [PMID: 36786575 PMCID: PMC10101105 DOI: 10.1128/spectrum.03957-22] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 01/23/2023] [Indexed: 02/15/2023] Open
Abstract
Nematode-trapping (NT) fungi are a unique group of carnivorous microorganisms that can capture and digest nematodes by producing ingenious trapping devices (traps). Arthrobotrys oligospora, a representative NT fungus, can develop adhesive three-dimensional networks for nematode predation. Hyphal fusion is indispensable for the trap formation of A. oligospora. Here, we characterized an orthologous Ste12 protein (AoSte12) in A. oligospora via gene disruption, DNA affinity purification sequencing (DAP-Seq), and multi-omics approaches. The disruption of the Aoste12 gene caused an increase in hyphal fusion and resulted in defects in mycelial growth, conidiation, trap morphology, and stress resistance, as well as reducing the number of nuclei and lipid droplet accumulation. Moreover, transcriptome and DAP-Seq analysis revealed that AoSte12 was involved in cellular processes associated with growth, cell fusion, the tricarboxylic acid cycle, vesicles, actin filaments, and lipid metabolism. In addition, combining metabolome with transcriptome and DAP-Seq analysis indicated that AoSte12 was involved in the mitogen-activated protein kinase signaling pathway, lipid metabolism, and secondary metabolites. A yeast two-hybrid assay revealed that AoSte12 can interact with diverse proteins, such as the MAK-2 orthologue protein Fus3, the vacuolar sorting protein Pep3, and UDP-glycosyltransferase. Our results suggest that AoSte12 plays an indispensable role in hyphal fusion and thus regulates sporulation and trap morphogenesis. These results provide deep insights into the connection between hyphal fusion and trap formation in NT fungi. IMPORTANCE Nematode-trapping (NT) fungi are an important natural enemy of nematodes and can capture their prey by producing traps. Hyphal anastomosis and fusion are important for mycelial growth and the colony morphological development of filamentous fungi and are also crucial for the trap morphogenesis of NT fungi. Arthrobotrys oligospora can form complex three-dimensional networks (traps) when sensing the presence of nematodes. This study revealed that AoSte12 is indispensable for hyphal fusion and that it regulates mycelial growth, conidiation, trap morphogenesis, stress resistance, the number of nuclei, and lipid droplet accumulation in A. oligospora. In addition, DNA affinity purification sequencing, transcriptome, and metabolome analyses further revealed that AoSte12 is involved in the mitogen-activated protein kinase pathway, lipid metabolism, and secondary metabolism. Overall, these findings expand the important role of AoSte12 in NT fungus A. oligospora and provide a broad foundation for elucidating the regulatory mechanism of trap development and the lifestyle transitions of pathogenic fungi.
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Affiliation(s)
- Na Bai
- State Key Laboratory for Conservation and Utilization of Bio-Resources and Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, People’s Republic of China
- School of Life Sciences, Yunnan University, Kunming, People’s Republic of China
| | - Meihua Xie
- State Key Laboratory for Conservation and Utilization of Bio-Resources and Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, People’s Republic of China
- School of Life Sciences, Yunnan University, Kunming, People’s Republic of China
| | - Qianqian Liu
- State Key Laboratory for Conservation and Utilization of Bio-Resources and Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, People’s Republic of China
- School of Life Sciences, Yunnan University, Kunming, People’s Republic of China
| | - Wenjie Wang
- State Key Laboratory for Conservation and Utilization of Bio-Resources and Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, People’s Republic of China
- School of Life Sciences, Yunnan University, Kunming, People’s Republic of China
| | - Yankun Liu
- State Key Laboratory for Conservation and Utilization of Bio-Resources and Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, People’s Republic of China
- School of Life Sciences, Yunnan University, Kunming, People’s Republic of China
| | - Jinkui Yang
- State Key Laboratory for Conservation and Utilization of Bio-Resources and Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, People’s Republic of China
- School of Life Sciences, Yunnan University, Kunming, People’s Republic of China
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Villalobos-Escobedo JM, Martínez-Hernández JP, Pelagio-Flores R, González-De la Rosa PM, Carreras-Villaseñor N, Abreu-Goodger C, Herrera-Estrella AH. Trichoderma atroviride hyphal regeneration and conidiation depend on cell-signaling processes regulated by a microRNA-like RNA. Microb Genom 2022; 8. [PMID: 36239595 DOI: 10.1099/mgen.0.000869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The ability to respond to injury is essential for the survival of an organism and involves analogous mechanisms in animals and plants. Such mechanisms integrate coordinated genetic and metabolic reprogramming events requiring regulation by small RNAs for adequate healing of the wounded area. We have previously reported that the response to injury of the filamentous fungus Trichoderma atroviride involves molecular mechanisms closely resembling those of plants and animals that lead to the formation of new hyphae (regeneration) and the development of asexual reproduction structures (conidiophores). However, the involvement of microRNAs in this process has not been investigated in fungi. In this work, we explore the participation of microRNA-like RNAs (milRNAs) molecules by sequencing messenger and small RNAs during the injury response of the WT strain and RNAi mutants. We found that Dcr2 appears to play an important role in hyphal regeneration and is required to produce the majority of sRNAs in T. atroviride. We also determined that the three main milRNAs produced via Dcr2 are induced during the damage-triggered developmental process. Importantly, elimination of a single milRNA phenocopied the main defects observed in the dcr2 mutant. Our results demonstrate the essential role of milRNAs in hyphal regeneration and asexual development by post-transcriptionally regulating cellular signalling processes involving phosphorylation events. These observations allow us to conclude that fungi, like plants and animals, in response to damage activate fine-tuning regulatory mechanisms.
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Affiliation(s)
- José M Villalobos-Escobedo
- Laboratorio Nacional de Genómica para la Biodiversidad-Unidad de Genómica Avanzada, Cinvestav. Km 9.6 Libramiento Norte Carretera Irapuato-León, 36824, Irapuato, Gto, Mexico
| | - J Pedro Martínez-Hernández
- Laboratorio Nacional de Genómica para la Biodiversidad-Unidad de Genómica Avanzada, Cinvestav. Km 9.6 Libramiento Norte Carretera Irapuato-León, 36824, Irapuato, Gto, Mexico
| | - Ramón Pelagio-Flores
- Laboratorio Nacional de Genómica para la Biodiversidad-Unidad de Genómica Avanzada, Cinvestav. Km 9.6 Libramiento Norte Carretera Irapuato-León, 36824, Irapuato, Gto, Mexico.,Present address: Facultad de Químico Farmacobiología, Universidad Michoacana de San Nicolás de Hidalgo, C.P. 58030 Morelia, Michoacán, Mexico
| | - Pablo M González-De la Rosa
- Laboratorio Nacional de Genómica para la Biodiversidad-Unidad de Genómica Avanzada, Cinvestav. Km 9.6 Libramiento Norte Carretera Irapuato-León, 36824, Irapuato, Gto, Mexico.,Present address: Tree of Life, Wellcome Sanger Institute, Cambridge CB10 1SA, UK
| | - Nohemí Carreras-Villaseñor
- Laboratorio Nacional de Genómica para la Biodiversidad-Unidad de Genómica Avanzada, Cinvestav. Km 9.6 Libramiento Norte Carretera Irapuato-León, 36824, Irapuato, Gto, Mexico.,Present address: Red de Estudios Moleculares Avanzados, Instituto de Ecología A.C. C.P. 91070 Xalapa, Veracruz, Mexico
| | - Cei Abreu-Goodger
- Laboratorio Nacional de Genómica para la Biodiversidad-Unidad de Genómica Avanzada, Cinvestav. Km 9.6 Libramiento Norte Carretera Irapuato-León, 36824, Irapuato, Gto, Mexico.,Present address: Institute of Ecology and Evolution, University of Edinburgh, Edinburgh, UK
| | - Alfredo H Herrera-Estrella
- Laboratorio Nacional de Genómica para la Biodiversidad-Unidad de Genómica Avanzada, Cinvestav. Km 9.6 Libramiento Norte Carretera Irapuato-León, 36824, Irapuato, Gto, Mexico
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11
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ATP-Binding Cassette (ABC) Transporters in Fusarium Specific Mycoparasite Sphaerodes mycoparasitica during Biotrophic Mycoparasitism. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12157641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Recent transcriptomic profiling has revealed importance membrane transporters such as ATP-binding cassette (ABC) transporters in fungal necrotrophic mycoparasites. In this study, RNA-Seq allowed rapid detection of ABC transcripts involved in biotrophic mycoparasitism of Sphaerodes mycoparasitica against the phytopathogenic and mycotoxigenic Fusarium graminearum host, the causal agent of Fusarium head blight (FHB). Transcriptomic analyses of highly expressed S. mycoparasitica genes, and their phylogenetic relationships with other eukaryotic fungi, portrayed the ABC transporters’ evolutionary paths towards biotrophic mycoparasitism. Prior to the in silico phylogenetic analyses, transmission electron microscopy (TEM) was used to confirm the formation of appressorium/haustorium infection structures in S. mycoparasitica during early (1.5 d and 3.5 d) stages of mycoparasitism. Transcripts encoding biotrophy-associated secreted proteins did uncover the enrolment of ABC transporter genes in this specific biocontrol mode of action, while tandem ABC and BUB2 (non-ABC) transcripts seemed to be proper for appressorium development. The next-generation HiSeq transcriptomic profiling of the mycoparasitic hypha samples, revealed 81 transcripts annotated to ABC transporters consisting of a variety of ABC-B (14%), ABC-C (22%), and ABC-G (23%), and to ABC-A, ABC-F, aliphatic sulfonates importer (TC 3.A.1.17.2), BtuF, ribose importer (TC 3.A.1.2.1), and unknown families. The most abundant transcripts belonged to the multidrug resistance exporter (TC 3.A.1.201) subfamily of the ABC-B family, the conjugate transporter (TC 3.A.1.208) subfamily of the ABC-C family, and the pleiotropic drug resistance (PDR) (TC 3.A.1.205) subfamily of the ABC-G family. These findings highlight the significance of ABC transporter genes that control cellular detoxification against toxic substances (e.g., chemical pesticides and mycotoxins) in sustaining a virulence of S. mycoparasitica for effective biotrophic mycoparasitism on the F. graminearum host. The findings of this study provide clues to better understand the biotrophic mycoparasitism of S. mycoparasitica interacting with the Fusarium host, which implies that the ABC transporter group of key proteins is involved in the mycoparasite’s virulence and multidrug resistance to toxic substances including cellular detoxification.
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Lv B, Fan L, Li S, Sun M. Screening and characterisation of proteins interacting with the mitogen-activated protein kinase Crmapk in the fungus Clonostachys chloroleuca. Sci Rep 2022; 12:9997. [PMID: 35705642 PMCID: PMC9200739 DOI: 10.1038/s41598-022-13899-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 05/30/2022] [Indexed: 11/15/2022] Open
Abstract
Clonostachys chloroleuca 67-1 (formerly C. rosea 67-1) is a promising mycoparasite with great potential for controlling various plant fungal diseases. The mitogen-activated protein kinase (MAPK)-encoding gene Crmapk is of great importance to the mycoparasitism and biocontrol activities of C. chloroleuca. To investigate the molecular mechanisms underlying the role of Crmapk in mycoparasitism, a high-quality yeast two hybrid (Y2H) library of C. chloroleuca 67-1 was constructed, and proteins interacting with Crmapk were characterised. The library contained 1.6 × 107 independent clones with a recombination rate of 96%, and most inserted fragments were > 1 kb. The pGBKT7-Crmapk bait vector with no self-activation or toxicity to yeast cells was used to screen interacting proteins from the Y2H library, resulting in 60 candidates, many linked to metabolism, cellular processes and signal transduction. Combined bioinformatics and transcriptome analyses of C. chloroleuca 67-1 and ΔCrmapk mutant mycoparasitising Sclerotinia sclerotiorum sclerotia, 41 differentially expressed genes were identified, which might be the targets of the Fus3/Kss1-MAPK pathway. The results provide a profile of potential protein interactions associated with MAPK enzymes in mycoparasites, and are of great significance for understanding the mechanisms of Crmapk regulating C. chloroleuca mycoparasitism.
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Affiliation(s)
- Binna Lv
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Lele Fan
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Shidong Li
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Manhong Sun
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China.
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A dialogue-like cell communication mechanism is conserved in filamentous ascomycete fungi and mediates interspecies interactions. Proc Natl Acad Sci U S A 2022; 119:e2112518119. [PMID: 35286209 PMCID: PMC8944665 DOI: 10.1073/pnas.2112518119] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
This study reveals that a dialogue-like communication mechanism, which mediates cell–cell fusion in filamentous fungi, is a conserved complex trait. It allows the communication and behavioral coordination of cells of distantly related species and mediates their mutual attraction and subsequent physical contact, although interspecies fusion does not occur. Through the activation of this signaling machinery, one species can reprogram the developmental program of the other fungus. These data promote our understanding of microbial communication, illustrate the mechanism of repurposing of existing building blocks in cellular evolution, revive the hypothesis of vegetative fusion as an avenue of horizontal gene transfer in fungi, and establish the idea of developmental reprogramming as a tool for controlling fungi. In many filamentous fungi, germinating spores cooperate by fusing into supracellular structures, which develop into the mycelial colony. In the model fungus Neurospora crassa, this social behavior is mediated by an intriguing mode of communication, in which two fusing cells take turns in signal sending and receiving. Here we show that this dialogue-like cell communication mechanism is highly conserved in distantly related fungal species and mediates interspecies interactions. In mixed populations, cells of N. crassa and the phytopathogenic gray mold Botrytis cinerea coordinate their behavior over a spatial distance and establish physical contact. Subsequent cell–cell fusion is, however, restricted to germlings of the same species, indicating that species specificity of germling fusion has evolved not on the level of the signal/receptor but at subsequent levels of the fusion process. In B. cinerea, fusion and infectious growth are mutually exclusive cellular programs. Remarkably, the presence of N. crassa can reprogram this behavior and induce fusion of the gray mold on plant surfaces, potentially weakening its pathogenic potential. In a third fungal species, the nematode-trapping fungus Arthrobotrys flagrans, the conserved signaling mechanism mediates vegetative fusion within mycelial colonies but has also been repurposed for the formation of nematode-catching traps. In summary, this study identified the cell dialogue mechanism as a conserved complex trait and revealed that even distantly related fungi possess a common molecular language, which promotes cellular contact formation across species borders.
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15
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Rosolen RR, Aono AH, Almeida DA, Ferreira Filho JA, Horta MAC, De Souza AP. Network Analysis Reveals Different Cellulose Degradation Strategies Across Trichoderma harzianum Strains Associated With XYR1 and CRE1. Front Genet 2022; 13:807243. [PMID: 35281818 PMCID: PMC8912865 DOI: 10.3389/fgene.2022.807243] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 02/04/2022] [Indexed: 12/24/2022] Open
Abstract
Trichoderma harzianum, whose gene expression is tightly controlled by the transcription factors (TFs) XYR1 and CRE1, is a potential candidate for hydrolytic enzyme production. Here, we performed a network analysis of T. harzianum IOC-3844 and T. harzianum CBMAI-0179 to explore how the regulation of these TFs varies between these strains. In addition, we explored the evolutionary relationships of XYR1 and CRE1 protein sequences among Trichoderma spp. The results of the T. harzianum strains were compared with those of Trichoderma atroviride CBMAI-0020, a mycoparasitic species. Although transcripts encoding carbohydrate-active enzymes (CAZymes), TFs, transporters, and proteins with unknown functions were coexpressed with cre1 or xyr1, other proteins indirectly related to cellulose degradation were identified. The enriched GO terms describing the transcripts of these groups differed across all strains, and several metabolic pathways with high similarity between both regulators but strain-specific differences were identified. In addition, the CRE1 and XYR1 subnetworks presented different topology profiles in each strain, likely indicating differences in the influences of these regulators according to the fungi. The hubs of the cre1 and xyr1 groups included transcripts not yet characterized or described as being related to cellulose degradation. The first-neighbor analyses confirmed the results of the profile of the coexpressed transcripts in cre1 and xyr1. The analyses of the shortest paths revealed that CAZymes upregulated under cellulose degradation conditions are most closely related to both regulators, and new targets between such signaling pathways were discovered. Although the evaluated T. harzianum strains are phylogenetically close and their amino acid sequences related to XYR1 and CRE1 are very similar, the set of transcripts related to xyr1 and cre1 differed, suggesting that each T. harzianum strain used a specific regulation strategy for cellulose degradation. More interestingly, our findings may suggest that XYR1 and CRE1 indirectly regulate genes encoding proteins related to cellulose degradation in the evaluated T. harzianum strains. An improved understanding of the basic biology of fungi during the cellulose degradation process can contribute to the use of their enzymes in several biotechnological applications and pave the way for further studies on the differences across strains of the same species.
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Affiliation(s)
- Rafaela Rossi Rosolen
- Center for Molecular Biology and Genetic Engineering (CBMEG), University of Campinas (UNICAMP), Campinas, Brazil
- Graduate Program in Genetics and Molecular Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
| | - Alexandre Hild Aono
- Center for Molecular Biology and Genetic Engineering (CBMEG), University of Campinas (UNICAMP), Campinas, Brazil
- Graduate Program in Genetics and Molecular Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
| | - Déborah Aires Almeida
- Center for Molecular Biology and Genetic Engineering (CBMEG), University of Campinas (UNICAMP), Campinas, Brazil
- Graduate Program in Genetics and Molecular Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
| | - Jaire Alves Ferreira Filho
- Center for Molecular Biology and Genetic Engineering (CBMEG), University of Campinas (UNICAMP), Campinas, Brazil
- Graduate Program in Genetics and Molecular Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
| | | | - Anete Pereira De Souza
- Center for Molecular Biology and Genetic Engineering (CBMEG), University of Campinas (UNICAMP), Campinas, Brazil
- Department of Plant Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
- *Correspondence: Anete Pereira De Souza,
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16
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Kappel L, Kosa N, Gruber S. The Multilateral Efficacy of Chitosan and Trichoderma on Sugar Beet. J Fungi (Basel) 2022; 8:jof8020137. [PMID: 35205892 PMCID: PMC8879458 DOI: 10.3390/jof8020137] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 01/24/2022] [Accepted: 01/26/2022] [Indexed: 02/04/2023] Open
Abstract
The majority of all fungal formulations contain Trichoderma spp., making them effective biological control agents for agriculture. Chitosan, one of the most effective natural biopolymers, was also reported as a plant resistance enhancer and as a biocide against a variety of plant pathogens. An in vitro three-way interaction assay of T. atroviride, chitosan, and important plant pathogens (such as Cercospora beticola and Fusarium oxysporum) revealed a synergistic effect on fungistasis. Furthermore, chitosan coating on Beta vulgaris ssp. vulgaris seeds positively affected the onset and efficiency of germination. We show that priming with T. atroviride spores or chitosan leads to the induced expression of a pathogenesis-related gene (PR-3), but only supplementation of chitosan led to significant upregulation of phytoalexin synthesis (PAL) and oxidative stress-related genes (GST) as a defense response. Repeated foliar application of either agent promoted growth, triggered defense reactions, and reduced incidence of Cercospora leaf spot (CLS) disease in B. vulgaris. Our data suggest that both agents are excellent candidates to replace or assist common fungicides in use. Chitosan triggered the systemic resistance and had a biocidal effect, while T. atroviride mainly induced stress-related defense genes in B. vulgaris. We assume that both agents act synergistically across different signaling pathways, which could be of high relevance for their combinatorial and thus beneficial application on field.
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Affiliation(s)
- Lisa Kappel
- Department of Microbiology, University of Innsbruck, 6020 Innsbruck, Austria;
- Department of Bioengineering, FH Campus Wien, University of Applied Sciences, 1190 Vienna, Austria;
| | - Nicole Kosa
- Department of Bioengineering, FH Campus Wien, University of Applied Sciences, 1190 Vienna, Austria;
| | - Sabine Gruber
- Department of Microbiology, University of Innsbruck, 6020 Innsbruck, Austria;
- Department of Bioengineering, FH Campus Wien, University of Applied Sciences, 1190 Vienna, Austria;
- Correspondence:
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Wang Y, Li J, Chen Q, Zhou J, Xu J, Zhao T, Huang B, Miao Y, Liu D. The role of antifungal activity of ethyl acetate extract from Artemisia argyi on Verticillium dahliae. J Appl Microbiol 2021; 132:1343-1356. [PMID: 34496104 DOI: 10.1111/jam.15298] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Revised: 08/19/2021] [Accepted: 08/31/2021] [Indexed: 11/30/2022]
Abstract
AIMS This study investigated the antifungal activity and mechanisms of ethyl acetate extract of Artemisia argyi (EAAA) against Verticillium dahliae. METHODS AND RESULTS Optical and scanning electron microscopy observation showed that 2.0 mg ml-1 EAAA treatment reduced spore germination rate to 4.56%. Histochemical staining showed that 2.0 mg ml-1 EAAA treatment increased reactive oxygen species (ROS) by more than two times. Physiological test showed that EAAA treatment decreased the contents of soluble proteins and sugars, and reduced the activities of malate dehydrogenase and succinate dehydrogenase by nearly half. Transcriptome analysis showed that EAAA treatment down-regulated the expression of genes involved in primary metabolic pathways of V. dahliae. CONCLUSIONS Our results revealed that EAAA inhibited the growth and development of V. dahliae from multiple levels and multiple targets, including inhibiting the germination and development of V. dahliae spores, destroying the structure of cell membranes, inducing ROS burst, reducing the activities of respiratory-related enzymes and down-regulating the expression of genes in primary metabolic pathways. SIGNIFICANCE AND IMPACT OF THE STUDY The mechanism of the multitarget effects of EAAA against V. dahliae may limit the potential of fungus developing resistance and provide the efficient methods to control verticillium wilt disease in the future.
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Affiliation(s)
- Yunhan Wang
- Hubei Provincial Key Laboratory of Resource Science and Chemistry in Chinese Medicine, Hubei University of Chinese Medicine, Wuhan, Hubei, China
| | - Jinxin Li
- Hubei Provincial Key Laboratory of Resource Science and Chemistry in Chinese Medicine, Hubei University of Chinese Medicine, Wuhan, Hubei, China
| | - Qiaohuan Chen
- Hubei Provincial Key Laboratory of Resource Science and Chemistry in Chinese Medicine, Hubei University of Chinese Medicine, Wuhan, Hubei, China
| | - Jia Zhou
- Hubei Provincial Key Laboratory of Resource Science and Chemistry in Chinese Medicine, Hubei University of Chinese Medicine, Wuhan, Hubei, China
| | - Jiawei Xu
- Hubei Provincial Key Laboratory of Resource Science and Chemistry in Chinese Medicine, Hubei University of Chinese Medicine, Wuhan, Hubei, China
| | - Tingting Zhao
- Hubei Provincial Key Laboratory of Resource Science and Chemistry in Chinese Medicine, Hubei University of Chinese Medicine, Wuhan, Hubei, China
| | - Bisheng Huang
- Hubei Provincial Key Laboratory of Resource Science and Chemistry in Chinese Medicine, Hubei University of Chinese Medicine, Wuhan, Hubei, China
| | - Yuhuan Miao
- Hubei Provincial Key Laboratory of Resource Science and Chemistry in Chinese Medicine, Hubei University of Chinese Medicine, Wuhan, Hubei, China
| | - Dahui Liu
- Hubei Provincial Key Laboratory of Resource Science and Chemistry in Chinese Medicine, Hubei University of Chinese Medicine, Wuhan, Hubei, China
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Zhang X, Wang Z, Jiang C, Xu JR. Regulation of biotic interactions and responses to abiotic stresses by MAP kinase pathways in plant pathogenic fungi. STRESS BIOLOGY 2021; 1:5. [PMID: 37676417 PMCID: PMC10429497 DOI: 10.1007/s44154-021-00004-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 07/19/2021] [Indexed: 09/08/2023]
Abstract
Like other eukaryotes, fungi use MAP kinase (MAPK) pathways to mediate cellular changes responding to external stimuli. In the past two decades, three well-conserved MAP kinase pathways have been characterized in various plant pathogenic fungi for regulating responses and adaptations to a variety of biotic and abiotic stresses encountered during plant infection or survival in nature. The invasive growth (IG) pathway is homologous to the yeast pheromone response and filamentation pathways. In plant pathogens, the IG pathway often is essential for pathogenesis by regulating infection-related morphogenesis, such as appressorium formation, penetration, and invasive growth. The cell wall integrity (CWI) pathway also is important for plant infection although the infection processes it regulates vary among fungal pathogens. Besides its universal function in cell wall integrity, it often plays a minor role in responses to oxidative and cell wall stresses. Both the IG and CWI pathways are involved in regulating known virulence factors as well as effector genes during plant infection and mediating defenses against mycoviruses, bacteria, and other fungi. In contrast, the high osmolarity growth (HOG) pathway is dispensable for virulence in some fungi although it is essential for plant infection in others. It regulates osmoregulation in hyphae and is dispensable for appressorium turgor generation. The HOG pathway also plays a major role for responding to oxidative, heat, and other environmental stresses and is overstimulated by phenylpyrrole fungicides. Moreover, these three MAPK pathways crosstalk and coordinately regulate responses to various biotic and abiotic stresses. The IG and CWI pathways, particularly the latter, also are involved in responding to abiotic stresses to various degrees in different fungal pathogens, and the HOG pathway also plays a role in interactions with other microbes or fungi. Furthermore, some infection processes or stress responses are co-regulated by MAPK pathways with cAMP or Ca2+/CaM signaling. Overall, functions of individual MAP kinase pathways in pathogenesis and stress responses have been well characterized in a number of fungal pathogens, showing the conserved genetic elements with diverged functions, likely by rewiring transcriptional regulatory networks. In the near future, applications of genomics and proteomics approaches will likely lead to better understanding of crosstalk among the MAPKs and with other signaling pathways as well as roles of MAPKs in defense against other microbes (biotic interactions).
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Affiliation(s)
- Xue Zhang
- State Key Laboratory of Crop Stress Biology for Arid Areas and NWAFU-Purdue Joint Research Center, College of Plant Protection, Northwest A&F University, Yangling, 712100, Shaanxi, China
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, 47907, USA
| | - Zeyi Wang
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, 47907, USA
| | - Cong Jiang
- State Key Laboratory of Crop Stress Biology for Arid Areas and NWAFU-Purdue Joint Research Center, College of Plant Protection, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Jin-Rong Xu
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, 47907, USA.
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Moreno-Ruiz D, Salzmann L, Fricker MD, Zeilinger S, Lichius A. Stress-Activated Protein Kinase Signalling Regulates Mycoparasitic Hyphal-Hyphal Interactions in Trichoderma atroviride. J Fungi (Basel) 2021; 7:jof7050365. [PMID: 34066643 PMCID: PMC8148604 DOI: 10.3390/jof7050365] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 04/30/2021] [Accepted: 05/01/2021] [Indexed: 11/30/2022] Open
Abstract
Trichoderma atroviride is a mycoparasitic fungus used as biological control agent against fungal plant pathogens. The recognition and appropriate morphogenetic responses to prey-derived signals are essential for successful mycoparasitism. We established microcolony confrontation assays using T. atroviride strains expressing cell division cycle 42 (Cdc42) and Ras-related C3 botulinum toxin substrate 1 (Rac1) interactive binding (CRIB) reporters to analyse morphogenetic changes and the dynamic displacement of localized GTPase activity during polarized tip growth. Microscopic analyses showed that Trichoderma experiences significant polarity stress when approaching its fungal preys. The perception of prey-derived signals is integrated via the guanosine triphosphatase (GTPase) and mitogen-activated protein kinase (MAPK) signalling network, and deletion of the MAP kinases Trichoderma MAPK 1 (Tmk1) and Tmk3 affected T. atroviride tip polarization, chemotropic growth, and contact-induced morphogenesis so severely that the establishment of mycoparasitism was highly inefficient to impossible. The responses varied depending on the prey species and the interaction stage, reflecting the high selectivity of the signalling process. Our data suggest that Tmk3 affects the polarity-stress adaptation process especially during the pre-contact phase, whereas Tmk1 regulates contact-induced morphogenesis at the early-contact phase. Neither Tmk1 nor Tmk3 loss-of-function could be fully compensated within the GTPase/MAPK signalling network underscoring the crucial importance of a sensitive polarized tip growth apparatus for successful mycoparasitism.
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Affiliation(s)
- Dubraska Moreno-Ruiz
- Department of Microbiology, University of Innsbruck, 6020 Innsbruck, Austria; (D.M.-R.); (L.S.); (S.Z.)
| | - Linda Salzmann
- Department of Microbiology, University of Innsbruck, 6020 Innsbruck, Austria; (D.M.-R.); (L.S.); (S.Z.)
| | - Mark D. Fricker
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, UK;
| | - Susanne Zeilinger
- Department of Microbiology, University of Innsbruck, 6020 Innsbruck, Austria; (D.M.-R.); (L.S.); (S.Z.)
| | - Alexander Lichius
- Department of Microbiology, University of Innsbruck, 6020 Innsbruck, Austria; (D.M.-R.); (L.S.); (S.Z.)
- Correspondence:
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Atanasova L, Moreno-Ruiz D, Grünwald-Gruber C, Hell V, Zeilinger S. The GPI-Anchored GH76 Protein Dfg5 Affects Hyphal Morphology and Osmoregulation in the Mycoparasite Trichoderma atroviride and Is Interconnected With MAPK Signaling. Front Microbiol 2021; 12:601113. [PMID: 33643233 PMCID: PMC7902864 DOI: 10.3389/fmicb.2021.601113] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 01/05/2021] [Indexed: 11/13/2022] Open
Abstract
The fungal cell wall is composed of a cross-linked matrix of chitin, glucans, mannans, galactomannans, and cell wall proteins with mannan chains. Cell wall mannans are directly attached to the cell wall core, while the majority of mannoproteins is produced with a glycosylphosphatidylinositol (GPI) anchor and then transferred to β-1,6-glucan in the cell wall. In this study, we functionally characterized the transmembrane protein Dfg5 of the glycoside hydrolase family 76 (GH76) in the fungal mycoparasite Trichoderma atroviride, whose ortholog has recently been proposed to cross-link glycoproteins into the cell wall of yeast and fungi. We show that the T. atroviride Dfg5 candidate is a GPI-anchored, transmembrane, 6-hairpin member of the GH76 Dfg5 subfamily that plays an important role in hyphal morphology in this mycoparasite. Alterations in the release of proteins associated with cell wall remodeling as well as a higher amount of non-covalently bonded cell surface proteins were detected in the mutants compared to the wild-type. Gene expression analysis suggests that transcript levels of genes involved in glucan synthesis, of proteases involved in mycoparasitism, and of the Tmk1 mitogen-activated protein kinase (MAPK)-encoding gene are influenced by Dfg5, whereas Tmk3 governs Dfg5 transcription. We show that Dfg5 controls important physiological properties of T. atroviride, such as osmotic stress resistance, hyphal morphology, and cell wall stability.
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Affiliation(s)
- Lea Atanasova
- Department of Microbiology, University of Innsbruck, Innsbruck, Austria.,Department of Food Science and Technology, University of Natural Resources and Life Sciences, Vienna, Austria
| | | | - Clemens Grünwald-Gruber
- Division of Biochemistry, University of Natural Resources and Life Sciences, Vienna, Austria.,Core Facility Mass Spectrometry BOKU, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Viktoria Hell
- Department of Food Science and Technology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Susanne Zeilinger
- Department of Microbiology, University of Innsbruck, Innsbruck, Austria
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21
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Moreno-Ruiz D, Lichius A, Turrà D, Di Pietro A, Zeilinger S. Chemotropism Assays for Plant Symbiosis and Mycoparasitism Related Compound Screening in Trichoderma atroviride. Front Microbiol 2020; 11:601251. [PMID: 33329491 PMCID: PMC7729004 DOI: 10.3389/fmicb.2020.601251] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 11/04/2020] [Indexed: 01/29/2023] Open
Abstract
Trichoderma atroviride is a mycoparasitic fungus used as biological control agent to protect plants against fungal pathogens. Successful biocontrol is based on the perception of signals derived from both the plant symbiont and the fungal prey. Here, we applied three different chemotropic assays to study the chemosensing capacity of T. atroviride toward compounds known or suspected to play a role in the mycoparasite/plant or host/prey fungal interactions and to cover the complete spectrum of T. atroviride developmental stages. Purified compounds, including nutrients, the fungal secondary metabolite 6-amyl-α-pyrone (6-pentyl-α-pyrone, 6-PP) and the plant oxylipin 13-(s)-HODE, as well as culture supernatants derived from fungal preys, including Rhizoctonia solani, Botrytis cinerea and Fusarium oxysporum, were used to evaluate chemotropic responses of conidial germlings, microcolonies and fully differentiated mycelia. Our results show that germlings respond preferentially to compounds secreted by plant roots and T. atroviride itself than to compounds secreted by prey fungi. With the progression of colony development, host plant cues and self-generated signaling compounds remained the strongest chemoattractants. Nevertheless, mature hyphae responded differentially to certain prey-derived signals. Depending on the fungal prey species, chemotropic responses resulted in either increased or decreased directional colony extension and hyphal density at the colony periphery closest to the test compound source. Together these findings suggest that chemotropic sensing during germling development is focused on plant association and colony network formation, while fungal prey recognition develops later in mature hyphae of fully differentiated mycelium. Furthermore, the morphological alterations of T. atroviride in response to plant host and fungal prey compounds suggest the presence of both positive and negative chemotropism. The presented assays will be useful for screening of candidate compounds, and for evaluating their impact on the developmental spectrum of T. atroviride and other related species alike. Conidial germlings proved particularly useful for simple and rapid compound screening, whereas more elaborate microscopic analysis of microcolonies and fully differentiated mycelia was essential to understand process-specific responses, such as plant symbiosis and biocontrol.
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Affiliation(s)
| | - Alexander Lichius
- Department of Microbiology, University of Innsbruck, Innsbruck, Austria
| | - David Turrà
- Departamento de Genética, Universidad de Córdoba, Córdoba, Spain
| | | | - Susanne Zeilinger
- Department of Microbiology, University of Innsbruck, Innsbruck, Austria
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Speckbacher V, Ruzsanyi V, Martinez-Medina A, Hinterdobler W, Doppler M, Schreiner U, Böhmdorfer S, Beccaccioli M, Schuhmacher R, Reverberi M, Schmoll M, Zeilinger S. The Lipoxygenase Lox1 Is Involved in Light- and Injury-Response, Conidiation, and Volatile Organic Compound Biosynthesis in the Mycoparasitic Fungus Trichoderma atroviride. Front Microbiol 2020; 11:2004. [PMID: 32973724 PMCID: PMC7482316 DOI: 10.3389/fmicb.2020.02004] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2020] [Accepted: 07/29/2020] [Indexed: 12/24/2022] Open
Abstract
The necrotrophic mycoparasite Trichoderma atroviride is a biological pest control agent frequently applied in agriculture for the protection of plants against fungal phytopathogens. One of the main secondary metabolites produced by this fungus is 6-pentyl-α-pyrone (6-PP). 6-PP is an organic compound with antifungal and plant growth-promoting activities, whose biosynthesis was previously proposed to involve a lipoxygenase (Lox). In this study, we investigated the role of the single lipoxygenase-encoding gene lox1 encoded in the T. atroviride genome by targeted gene deletion. We found that light inhibits 6-PP biosynthesis but lox1 is dispensable for 6-PP production as well as for the ability of T. atroviride to parasitize and antagonize host fungi. However, we found Lox1 to be involved in T. atroviride conidiation in darkness, in injury-response, in the production of several metabolites, including oxylipins and volatile organic compounds, as well as in the induction of systemic resistance against the plant-pathogenic fungus Botrytis cinerea in Arabidopsis thaliana plants. Our findings give novel insights into the roles of a fungal Ile-group lipoxygenase and expand the understanding of a light-dependent role of these enzymes.
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Affiliation(s)
| | - Veronika Ruzsanyi
- Institute for Breath Research, University of Innsbruck, Innsbruck, Austria
| | - Ainhoa Martinez-Medina
- Plant-Microbe Interaction Unit, Institute of Natural Resources and Agrobiology of Salamanca (IRNASA-CSIC), Salamanca, Spain
| | - Wolfgang Hinterdobler
- Center for Health and Bioresources, AIT Austrian Institute of Technology, Tulln, Austria
| | - Maria Doppler
- Institute of Bioanalytics and Agro-Metabolomics, Department of Agrobiotechnology (IFA-Tulln), University of Natural Resources and Life Sciences, Vienna (BOKU), Tulln, Austria
| | - Ulrike Schreiner
- Department of Microbiology, University of Innsbruck, Innsbruck, Austria
| | - Stefan Böhmdorfer
- Department of Chemistry, University of Natural Resources and Life Sciences (BOKU), Tulln, Austria
| | | | - Rainer Schuhmacher
- Institute of Bioanalytics and Agro-Metabolomics, Department of Agrobiotechnology (IFA-Tulln), University of Natural Resources and Life Sciences, Vienna (BOKU), Tulln, Austria
| | - Massimo Reverberi
- Department of Environmental Biology, Sapienza University, Rome, Italy
| | - Monika Schmoll
- Center for Health and Bioresources, AIT Austrian Institute of Technology, Tulln, Austria
| | - Susanne Zeilinger
- Department of Microbiology, University of Innsbruck, Innsbruck, Austria
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Sun ZB, Wang Q, Sun MH, Li SD. The Mitogen-Activated Protein Kinase Gene Crmapk Is Involved in Clonostachys chloroleuca Mycoparasitism. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2020; 33:902-910. [PMID: 32282260 DOI: 10.1094/mpmi-03-20-0062-r] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Clonostachys chloroleuca is a mycoparasite used for biocontrol of numerous fungal plant pathogens. Sequencing of the transcriptome of C. chloroleuca following mycoparasitization of the sclerotia of Sclerotinia sclerotiorum revealed significant upregulation of a mitogen-activated protein kinase (MAPK)-encoding gene, crmapk. Although MAPKs are known to regulate fungal growth and development, the function of crmapk in C. chloroleuca mycoparasitism is unclear. In this study, we investigated the role of crmapk in C. chloroleuca mycoparasitism through gene knockout and complementation. Deletion of crmapk had no influence on the C. chloroleuca morphological characteristics but could significantly reduce the mycoparasitic ability to sclerotia and biocontrol capacity to soybean Sclerotinia stem rot; crmapk complementation restored these abilities. Transcriptome analysis between Δcrmapk and the wild-type strain revealed numerous genes were significantly down-regulated after crmapk deletion, including cytochrome P450, transporters, and cell wall-degrading enzymes (CWDEs). Our findings indicate that crmapk influences C. chloroleuca mycoparasitism by regulation of genes controlling the activity of CWDEs or antibiotic production. This study provides a basis for further studies of the molecular mechanism of C. chloroleuca mycoparasitism.
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Affiliation(s)
- Zhan-Bin Sun
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
- School of Light Industry, Beijing Technology and Business University, Beijing 100048, China
| | - Qi Wang
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Man-Hong Sun
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Shi-Dong Li
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
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Kappel L, Münsterkötter M, Sipos G, Escobar Rodriguez C, Gruber S. Chitin and chitosan remodeling defines vegetative development and Trichoderma biocontrol. PLoS Pathog 2020; 16:e1008320. [PMID: 32078661 PMCID: PMC7053769 DOI: 10.1371/journal.ppat.1008320] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 03/03/2020] [Accepted: 01/15/2020] [Indexed: 12/31/2022] Open
Abstract
Fungal parasitism depends on the ability to invade host organisms and mandates adaptive cell wall remodeling to avoid detection and defense reactions by the host. All plant and human pathogens share invasive strategies, which aid to escape the chitin-triggered and chitin-targeted host immune system. Here we describe the full spectrum of the chitin/chitosan-modifying enzymes in the mycoparasite Trichoderma atroviride with a central role in cell wall remodeling. Rapid adaption to a variety of growth conditions, environmental stresses and host defense mechanisms such as oxidative stress depend on the concerted interplay of these enzymes and, ultimately, are necessary for the success of the mycoparasitic attack. To our knowledge, we provide the first in class description of chitin and associated glycopolymer synthesis in a mycoparasite and demonstrate that they are essential for biocontrol. Eight chitin synthases, six chitin deacetylases, additional chitinolytic enzymes, including six chitosanases, transglycosylases as well as accessory proteins are involved in this intricately regulated process. Systematic and biochemical classification, phenotypic characterization and mycoparasitic confrontation assays emphasize the importance of chitin and chitosan assembly in vegetative development and biocontrol in T. atroviride. Our findings critically contribute to understanding the molecular mechanism of chitin synthesis in filamentous fungi and mycoparasites with the overarching goal to selectively exploit the discovered biocontrol strategies.
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Affiliation(s)
- Lisa Kappel
- Institute of Microbiology, University of Innsbruck, Innsbruck, Vienna, Austria
| | - Martin Münsterkötter
- Department of Functional Genomics and Bioinformatics, University of Sopron, Sopron, Hungary
| | - György Sipos
- Department of Functional Genomics and Bioinformatics, University of Sopron, Sopron, Hungary
| | | | - Sabine Gruber
- Institute of Microbiology, University of Innsbruck, Innsbruck, Vienna, Austria
- * E-mail:
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25
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Zhao X, Yang X, Lu Z, Wang H, He Z, Zhou G, Luo Z, Zhang Y. MADS-box transcription factor Mcm1 controls cell cycle, fungal development, cell integrity and virulence in the filamentous insect pathogenic fungus Beauveria bassiana. Environ Microbiol 2019; 21:3392-3416. [PMID: 30972885 DOI: 10.1111/1462-2920.14629] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 04/09/2019] [Indexed: 12/15/2022]
Abstract
MADS-box transcription factor Mcm1 plays crucial roles in regulating mating processes and pathogenesis in some fungi. However, its roles are varied in fungal species, and its function remains unclear in entomopathogenic fungi. Here, Mcm1 orthologue, Bbmcm1, was characterized in a filamentous entomopathogenic fungus, Beauveria bassiana. Disruption of Bbmcm1 resulted in a distinct reduction in growth with abnormal conidiogenesis, and a significant decrease in conidial viability with abnormal germination. ΔBbmcm1 displayed impaired cell integrity, with distorted cell wall structure and altered cell wall component. Abnormal cell cycle was detected in ΔBbmcm1 with longer G2 /M phase but shorter G1 /G0 and S phases in unicellular blastospores, and sparser septa in multicellular hyphae, which might be responsible for defects in development and differentiation due to the regulation of cell cycle-involved genes, as well as the corresponding cellular events-associated genes. Dramatically decreased virulence was examined in ΔBbmcm1, with impaired ability to escape haemocyte encapsulation, which was consistent with markedly reduced cuticle-degrading enzyme production by repressing their coding genes, and downregulated fungal effector protein-coding genes, suggesting a novel role of Mcm1 in interaction with host insect. These data indicate that Mcm1 is a crucial regulator of development, cell integrity, cell cycle and virulence in insect fungal pathogens.
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Affiliation(s)
- Xin Zhao
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural Sciences, Southwest University, Chongqing, 400715, People's Republic of China
| | - Xingju Yang
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural Sciences, Southwest University, Chongqing, 400715, People's Republic of China
| | - Zhuoyue Lu
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural Sciences, Southwest University, Chongqing, 400715, People's Republic of China
| | - Huifang Wang
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural Sciences, Southwest University, Chongqing, 400715, People's Republic of China
| | - Zhangjiang He
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural Sciences, Southwest University, Chongqing, 400715, People's Republic of China
| | - Guangyan Zhou
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural Sciences, Southwest University, Chongqing, 400715, People's Republic of China
| | - Zhibing Luo
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural Sciences, Southwest University, Chongqing, 400715, People's Republic of China
| | - Yongjun Zhang
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural Sciences, Southwest University, Chongqing, 400715, People's Republic of China
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Velmourougane K, Prasanna R, Supriya P, Ramakrishnan B, Thapa S, Saxena AK. Transcriptome profiling provides insights into regulatory factors involved in Trichoderma viride-Azotobacter chroococcum biofilm formation. Microbiol Res 2019; 227:126292. [PMID: 31421719 DOI: 10.1016/j.micres.2019.06.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 04/30/2019] [Accepted: 06/15/2019] [Indexed: 12/14/2022]
Abstract
Azotobacter chroococcum (Az) and Trichoderma viride (Tv) represent agriculturally important and beneficial plant growth promoting options which contribute towards nutrient management and biocontrol, respectively. When Az and Tv are co-cultured, they form a biofilm, which has proved promising as an inoculant in several crops; however, the basic aspects related to regulation of biofilm formation were not investigated. Therefore, whole transcriptome sequencing (Illumina NextSeq500) and gene expression analyses were undertaken, related to biofilm formation vis a vis Tv and Az growing individually. Significant changes in the transcriptome profiles of biofilm were recorded and validated through qPCR analyses. In-depth evaluation also identified several genes (phoA, phoB, glgP, alg8, sipW, purB, pssA, fadD) specifically involved in biofilm formation in Az, Tv and Tv-Az. Genes coding for RNA-dependent RNA polymerase, ABC transporters, translation elongation factor EF-1, molecular chaperones and double homeobox 4 were either up-regulated or down-regulated during biofilm formation. To our knowledge, this is the first report on the modulation of gene expression in an agriculturally beneficial association, as a biofilm. Our results provide insights into the regulatory factors involved during biofilm formation, which can help to improve the beneficial effects and develop more effective and promising plant- microbe associations.
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Affiliation(s)
| | - Radha Prasanna
- Division of Microbiology, ICAR-Indian Agricultural Research Institute, New Delhi, India.
| | - Puram Supriya
- Centre for Agricultural Bioinformatics, ICAR- Indian Agricultural Statistics Research Institute, New Delhi, India
| | | | - Shobit Thapa
- Division of Microbiology, ICAR-Indian Agricultural Research Institute, New Delhi, India
| | - Anil Kumar Saxena
- ICAR-National Bureau of Agriculturally Important Microorganisms (NBAIM), Kusmaur, PO Kaitholi, Mau Nath Bhanjan, Uttar Pradesh 275101, India
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27
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Medina-Castellanos E, Villalobos-Escobedo JM, Riquelme M, Read ND, Abreu-Goodger C, Herrera-Estrella A. Danger signals activate a putative innate immune system during regeneration in a filamentous fungus. PLoS Genet 2018; 14:e1007390. [PMID: 30500812 PMCID: PMC6291166 DOI: 10.1371/journal.pgen.1007390] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 12/12/2018] [Accepted: 10/19/2018] [Indexed: 01/24/2023] Open
Abstract
The ability to respond to injury is a biological process shared by organisms of different kingdoms that can even result in complete regeneration of a part or structure that was lost. Due to their immobility, multicellular fungi are prey to various predators and are therefore constantly exposed to mechanical damage. Nevertheless, our current knowledge of how fungi respond to injury is scarce. Here we show that activation of injury responses and hyphal regeneration in the filamentous fungus Trichoderma atroviride relies on the detection of two danger or alarm signals. As an early response to injury, we detected a transient increase in cytosolic free calcium ([Ca2+]c) that was promoted by extracellular ATP, and which is likely regulated by a mechanism of calcium-induced calcium-release. In addition, we demonstrate that the mitogen activated protein kinase Tmk1 plays a key role in hyphal regeneration. Calcium- and Tmk1-mediated signaling cascades activated major transcriptional changes early following injury, including induction of a set of regeneration associated genes related to cell signaling, stress responses, transcription regulation, ribosome biogenesis/translation, replication and DNA repair. Interestingly, we uncovered the activation of a putative fungal innate immune response, including the involvement of HET domain genes, known to participate in programmed cell death. Our work shows that fungi and animals share danger-signals, signaling cascades, and the activation of the expression of genes related to immunity after injury, which are likely the result of convergent evolution.
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Affiliation(s)
- Elizabeth Medina-Castellanos
- Laboratorio Nacional de Genómica para la Biodiversidad-Unidad de Genómica Avanzada, Cinvestav, Libramiento Norte Carretera Irapuato-León, Irapuato, Gto, Mexico
| | - José Manuel Villalobos-Escobedo
- Laboratorio Nacional de Genómica para la Biodiversidad-Unidad de Genómica Avanzada, Cinvestav, Libramiento Norte Carretera Irapuato-León, Irapuato, Gto, Mexico
| | - Meritxell Riquelme
- Department of Microbiology, Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE), Carretera Ensenada-Tijuana No. 3918, Ensenada, Baja California, Mexico
| | - Nick D. Read
- Manchester Fungal Infection Group, Division of Infection, Immunity and Respiratory Medicine, University of Manchester, Manchester, United Kingdom
| | - Cei Abreu-Goodger
- Laboratorio Nacional de Genómica para la Biodiversidad-Unidad de Genómica Avanzada, Cinvestav, Libramiento Norte Carretera Irapuato-León, Irapuato, Gto, Mexico
| | - Alfredo Herrera-Estrella
- Laboratorio Nacional de Genómica para la Biodiversidad-Unidad de Genómica Avanzada, Cinvestav, Libramiento Norte Carretera Irapuato-León, Irapuato, Gto, Mexico
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28
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The Gpr1-regulated Sur7 family protein Sfp2 is required for hyphal growth and cell wall stability in the mycoparasite Trichoderma atroviride. Sci Rep 2018; 8:12064. [PMID: 30104659 PMCID: PMC6089919 DOI: 10.1038/s41598-018-30500-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Accepted: 07/30/2018] [Indexed: 12/16/2022] Open
Abstract
Mycoparasites, e.g. fungi feeding on other fungi, are prominent within the genus Trichoderma and represent a promising alternative to chemical fungicides for plant disease control. We previously showed that the seven-transmembrane receptor Gpr1 regulates mycelial growth and asexual development and governs mycoparasitism-related processes in Trichoderma atroviride. We now describe the identification of genes being targeted by Gpr1 under mycoparasitic conditions. The identified gene set includes a candidate, sfp2, encoding a protein of the fungal-specific Sur7 superfamily, whose upregulation in T. atroviride upon interaction with a fungal prey is dependent on Gpr1. Sur7 family proteins are typical residents of membrane microdomains such as the membrane compartment of Can1 (MCC)/eisosome in yeast. We found that GFP-labeled Gpr1 and Sfp2 proteins show partly overlapping localization patterns in T. atroviride hyphae, which may point to shared functions and potential interaction during signal perception and endocytosis. Deletion of sfp2 caused heavily altered colony morphology, defects in polarized growth, cell wall integrity and endocytosis, and significantly reduced mycoparasitic activity, whereas sfp2 overexpression enhanced full overgrowth and killing of the prey. Transcriptional activation of a chitinase specific for hyphal growth and network formation and strong downregulation of chitin synthase-encoding genes were observed in Δsfp2. Taken together, these findings imply crucial functions of Sfp2 in hyphal morphogenesis of T. atroviride and its interaction with prey fungi.
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29
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Sun ZB, Wang Q, Zhang J, Jiang WZ, Wang Q, Li SD, Ma GZ, Sun MH. The transcription factor-encoding gene crtf is involved in Clonostachys chloroleuca mycoparasitism on Sclerotinia sclerotiorum. Microbiol Res 2018; 210:6-11. [PMID: 29625660 DOI: 10.1016/j.micres.2018.03.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Revised: 02/28/2018] [Accepted: 03/03/2018] [Indexed: 10/17/2022]
Abstract
Clonostachys chloroleuca 67-1 (formerly C. rosea 67-1) is a potential biocontrol fungus active against various fungal plant pathogens. From transcriptome sequencing of 67-1 parasitizing sclerotia of Sclerotinia sclerotiorum, we identified the transcription factor-encoding gene crtf that is significantly up-regulated during mycoparasitism. Transcription factors are widely distributed in fungi and involved in multiple biological processes. However, their role and regulatory mechanisms in mycoparasitism remain poorly understood. In this study, the function of crtf during 67-1 mycoparasitism was verified through gene knockout and complementation. The results showed that deletion of crtf did not influence fungal morphological characteristics, but the ability of the Δcrtf mutant to parasitize sclerotia and suppress soybean Sclerotinia white mold in the greenhouse was markedly diminished compared with the wild type strain. The biocontrol activity of Δcrtf recovered wild type levels when complemented with a plasmid expressing the crtf gene. These findings suggest that crtf plays a crucial role in C. chloroleuca mycoparasitism and provide insight into the molecular mechanisms underlying C. chloroleuca mycoparasitism on plant pathogenic fungi.
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Affiliation(s)
- Zhan-Bin Sun
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Qi Wang
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China; School of Marine Science and Technology, Huaihai Institute of Technology, Lianyungang, 222005, China
| | - Jun Zhang
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Wei-Zhi Jiang
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Qi Wang
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Shi-Dong Li
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Gui-Zhen Ma
- School of Marine Science and Technology, Huaihai Institute of Technology, Lianyungang, 222005, China
| | - Man-Hong Sun
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China.
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Druzhinina IS, Chenthamara K, Zhang J, Atanasova L, Yang D, Miao Y, Rahimi MJ, Grujic M, Cai F, Pourmehdi S, Salim KA, Pretzer C, Kopchinskiy AG, Henrissat B, Kuo A, Hundley H, Wang M, Aerts A, Salamov A, Lipzen A, LaButti K, Barry K, Grigoriev IV, Shen Q, Kubicek CP. Massive lateral transfer of genes encoding plant cell wall-degrading enzymes to the mycoparasitic fungus Trichoderma from its plant-associated hosts. PLoS Genet 2018; 14:e1007322. [PMID: 29630596 PMCID: PMC5908196 DOI: 10.1371/journal.pgen.1007322] [Citation(s) in RCA: 95] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 04/19/2018] [Accepted: 03/20/2018] [Indexed: 01/01/2023] Open
Abstract
Unlike most other fungi, molds of the genus Trichoderma (Hypocreales, Ascomycota) are aggressive parasites of other fungi and efficient decomposers of plant biomass. Although nutritional shifts are common among hypocrealean fungi, there are no examples of such broad substrate versatility as that observed in Trichoderma. A phylogenomic analysis of 23 hypocrealean fungi (including nine Trichoderma spp. and the related Escovopsis weberi) revealed that the genus Trichoderma has evolved from an ancestor with limited cellulolytic capability that fed on either fungi or arthropods. The evolutionary analysis of Trichoderma genes encoding plant cell wall-degrading carbohydrate-active enzymes and auxiliary proteins (pcwdCAZome, 122 gene families) based on a gene tree / species tree reconciliation demonstrated that the formation of the genus was accompanied by an unprecedented extent of lateral gene transfer (LGT). Nearly one-half of the genes in Trichoderma pcwdCAZome (41%) were obtained via LGT from plant-associated filamentous fungi belonging to different classes of Ascomycota, while no LGT was observed from other potential donors. In addition to the ability to feed on unrelated fungi (such as Basidiomycota), we also showed that Trichoderma is capable of endoparasitism on a broad range of Ascomycota, including extant LGT donors. This phenomenon was not observed in E. weberi and rarely in other mycoparasitic hypocrealean fungi. Thus, our study suggests that LGT is linked to the ability of Trichoderma to parasitize taxonomically related fungi (up to adelphoparasitism in strict sense). This may have allowed primarily mycotrophic Trichoderma fungi to evolve into decomposers of plant biomass. Individual fungi rely on particular host organisms or substrates for their nutrition. Therefore, the genomes of fungi feeding on plant biomass necessarily contain genes encoding plant cell wall-degrading enzymes, while animal parasites may depend on proteolytic activity. Molds in the genus Trichoderma (Ascomycota) display a unique nutritional versatility. They can feed on other fungi, attack animals, and degrade plant debris. The later property is so efficient that one species (T. reesei) is commercially used for the production of cellulolytic enzymes required for making biofuels and other industry. In this work, we have investigated the evolution of proteins required for plant cell wall degradation in nine Trichoderma genomes and found an unprecedented number of lateral gene transfer (LGT) events for genes encoding these enzymes. Interestingly, the transfers specifically occurred from Ascomycota molds that feed on plants. We detected no cases of LGT from other fungi (e.g., mushrooms or wood-rotting fungi from Basidiomycota) that are frequent hosts of Trichoderma. Therefore, we propose that LGT may be linked to the ability of Trichoderma to parasitize on related organisms. This is a characteristic ecological trait that distinguishes Trichoderma from other mycoparasitic fungi. In this report, we demonstrate that the lateral transfer of genes may result in a profound nutritional expansion and contribute to the emergence of a generalist capable of feeding on organic matter of any origin.
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Affiliation(s)
- Irina S. Druzhinina
- Microbiology and Applied Genomics Group, Research Area Biochemical Technology, Institute of Chemical, Environmental & Bioscience Engineering, TU Wien, Vienna, Austria
- * E-mail: (ISD); (QS)
| | - Komal Chenthamara
- Microbiology and Applied Genomics Group, Research Area Biochemical Technology, Institute of Chemical, Environmental & Bioscience Engineering, TU Wien, Vienna, Austria
| | - Jian Zhang
- Jiangsu Provincial Key Lab of Organic Solid Waste Utilization, Nanjing Agricultural University, Nanjing, China
| | - Lea Atanasova
- Microbiology and Applied Genomics Group, Research Area Biochemical Technology, Institute of Chemical, Environmental & Bioscience Engineering, TU Wien, Vienna, Austria
| | - Dongqing Yang
- Jiangsu Provincial Key Lab of Organic Solid Waste Utilization, Nanjing Agricultural University, Nanjing, China
| | - Youzhi Miao
- Jiangsu Provincial Key Lab of Organic Solid Waste Utilization, Nanjing Agricultural University, Nanjing, China
| | - Mohammad J. Rahimi
- Microbiology and Applied Genomics Group, Research Area Biochemical Technology, Institute of Chemical, Environmental & Bioscience Engineering, TU Wien, Vienna, Austria
| | - Marica Grujic
- Microbiology and Applied Genomics Group, Research Area Biochemical Technology, Institute of Chemical, Environmental & Bioscience Engineering, TU Wien, Vienna, Austria
| | - Feng Cai
- Microbiology and Applied Genomics Group, Research Area Biochemical Technology, Institute of Chemical, Environmental & Bioscience Engineering, TU Wien, Vienna, Austria
- Jiangsu Provincial Key Lab of Organic Solid Waste Utilization, Nanjing Agricultural University, Nanjing, China
| | - Shadi Pourmehdi
- Microbiology and Applied Genomics Group, Research Area Biochemical Technology, Institute of Chemical, Environmental & Bioscience Engineering, TU Wien, Vienna, Austria
| | - Kamariah Abu Salim
- Environmental and Life Sciences, Universiti Brunei Darussalam, Bandar Seri Begawan, Brunei Darussalam
| | - Carina Pretzer
- Microbiology and Applied Genomics Group, Research Area Biochemical Technology, Institute of Chemical, Environmental & Bioscience Engineering, TU Wien, Vienna, Austria
| | - Alexey G. Kopchinskiy
- Microbiology and Applied Genomics Group, Research Area Biochemical Technology, Institute of Chemical, Environmental & Bioscience Engineering, TU Wien, Vienna, Austria
| | - Bernard Henrissat
- Architecture et Fonction des Macromolécules Biologiques, CNRS, Aix-Marseille Université, Marseille, France
- INRA, USC 1408 AFMB, Marseille, France
- Department of Biological Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Alan Kuo
- US Department of Energy Joint Genome Institute, Walnut Creek, CA, United States of America
| | - Hope Hundley
- US Department of Energy Joint Genome Institute, Walnut Creek, CA, United States of America
| | - Mei Wang
- US Department of Energy Joint Genome Institute, Walnut Creek, CA, United States of America
| | - Andrea Aerts
- US Department of Energy Joint Genome Institute, Walnut Creek, CA, United States of America
| | - Asaf Salamov
- US Department of Energy Joint Genome Institute, Walnut Creek, CA, United States of America
| | - Anna Lipzen
- US Department of Energy Joint Genome Institute, Walnut Creek, CA, United States of America
| | - Kurt LaButti
- US Department of Energy Joint Genome Institute, Walnut Creek, CA, United States of America
| | - Kerrie Barry
- US Department of Energy Joint Genome Institute, Walnut Creek, CA, United States of America
| | - Igor V. Grigoriev
- US Department of Energy Joint Genome Institute, Walnut Creek, CA, United States of America
- Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, CA, United States of America
| | - Qirong Shen
- Jiangsu Provincial Key Lab of Organic Solid Waste Utilization, Nanjing Agricultural University, Nanjing, China
- * E-mail: (ISD); (QS)
| | - Christian P. Kubicek
- Microbiology and Applied Genomics Group, Research Area Biochemical Technology, Institute of Chemical, Environmental & Bioscience Engineering, TU Wien, Vienna, Austria
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Rubio MB, Pardal AJ, Cardoza RE, Gutiérrez S, Monte E, Hermosa R. Involvement of the Transcriptional Coactivator ThMBF1 in the Biocontrol Activity of Trichoderma harzianum. Front Microbiol 2017; 8:2273. [PMID: 29201024 PMCID: PMC5696597 DOI: 10.3389/fmicb.2017.02273] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 11/06/2017] [Indexed: 01/20/2023] Open
Abstract
Trichoderma harzianum is a filamentous fungus well adapted to different ecological niches. Owing to its ability to antagonize a wide range of plant pathogens, it is used as a biological control agent in agriculture. Selected strains of T. harzianum are also able to increase the tolerance of plants to biotic and abiotic stresses. However, little is known about the regulatory elements of the T. harzianum transcriptional machinery and their role in the biocontrol by this species. We had previously reported the involvement of the transcription factor THCTF1 in the T. harzianum production of the secondary metabolite 6-pentyl-pyrone, an important volatile compound related to interspecies cross-talk. Here, we performed a subtractive hybridization to explore the genes regulated by THCTF1, allowing us to identify a multiprotein bridging factor 1 (mbf1) homolog. The gene from T. harzianum T34 was isolated and characterized, and the generated Thmbf1 overexpressing transformants were used to investigate the role of this gene in the biocontrol abilities of the fungus against two plant pathogens. The transformants showed a reduced antifungal activity against Fusarium oxysporum f. sp. lycopersici race 2 (FO) and Botrytis cinerea (BC) in confrontation assays on discontinuous medium, indicating that the Thmbf1 gene could affect T. harzianum production of volatile organic compounds (VOC) with antifungal activity. Moreover, cellophane and dialysis membrane assays indicated that Thmbf1 overexpression affected the production of low molecular weight secreted compounds with antifungal activity against FO. Intriguingly, no correlation in the expression profiles, either in rich or minimal medium, was observed between Thmbf1 and the master regulator gene cross-pathway control (cpc1). Greenhouse assays allowed us to evaluate the biocontrol potential of T. harzianum strains against BC and FO on susceptible tomato plants. The wild type strain T34 significantly reduced the necrotic leaf lesions caused by BC while plants treated with the Thmbf1-overexpressing transformants exhibited an increased susceptibility to this pathogen. The percentages of Fusarium wilt disease incidence and values of aboveground dry weight showed that T34 did not have biocontrol activity against FO, at least in the ‘Moneymaker’ tomato variety, and that Thmbf1 overexpression increased the incidence of this disease. Our results show that the Thmbf1 overexpression in T34 negatively affects its biocontrol mechanisms.
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Affiliation(s)
- M Belén Rubio
- Spanish-Portuguese Institute for Agricultural Research (CIALE), Department of Microbiology and Genetics, University of Salamanca, Salamanca, Spain
| | - Alonso J Pardal
- Spanish-Portuguese Institute for Agricultural Research (CIALE), Department of Microbiology and Genetics, University of Salamanca, Salamanca, Spain
| | - Rosa E Cardoza
- Area of Microbiology, University School of Agricultural Engineers, University of León, Ponferrada, Spain
| | - Santiago Gutiérrez
- Area of Microbiology, University School of Agricultural Engineers, University of León, Ponferrada, Spain
| | - Enrique Monte
- Spanish-Portuguese Institute for Agricultural Research (CIALE), Department of Microbiology and Genetics, University of Salamanca, Salamanca, Spain
| | - Rosa Hermosa
- Spanish-Portuguese Institute for Agricultural Research (CIALE), Department of Microbiology and Genetics, University of Salamanca, Salamanca, Spain
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Martínez-Soto D, Ruiz-Herrera J. Functional analysis of the MAPK pathways in fungi. Rev Iberoam Micol 2017; 34:192-202. [PMID: 28732778 DOI: 10.1016/j.riam.2017.02.006] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 01/27/2017] [Accepted: 02/17/2017] [Indexed: 01/19/2023] Open
Abstract
The Mitogen-Activated Protein Kinase (MAPK) signaling pathways constitute one of the most important and evolutionarily conserved mechanisms for the perception of extracellular information in all the eukaryotic organisms. The MAPK pathways are involved in the transfer to the cell of the information perceived from extracellular stimuli, with the final outcome of activation of different transcription factors that regulate gene expression in response to them. In all species of fungi, the MAPK pathways have important roles in their physiology and development; e.g. cell cycle control, mating, morphogenesis, response to different stresses, resistance to UV radiation and to temperature changes, cell wall assembly and integrity, degradation of cellular organelles, virulence, cell-cell signaling, fungus-plant interaction, and response to damage-associated molecular patterns (DAMPs). Considering the importance of the phylogenetically conserved MAPK pathways in fungi, an updated review of the knowledge on them is discussed in this article. This information reveals their importance, their distribution in fungal species evolutionarily distant and with different lifestyles, their organization and function, and the interactions occurring between different MAPK pathways, and with other signaling pathways, for the regulation of the most complex cellular processes.
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Affiliation(s)
- Domingo Martínez-Soto
- Departamento de Ingeniería Genética, Unidad Irapuato, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Irapuato, Gto., Mexico
| | - José Ruiz-Herrera
- Departamento de Ingeniería Genética, Unidad Irapuato, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Irapuato, Gto., Mexico.
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Abstract
Mycoparasitism is a lifestyle where one fungus establishes parasitic interactions with other fungi. Species of the genus Trichoderma together with Clonostachys rosea are among the most studied fungal mycoparasites. They have wide host ranges comprising several plant pathogens and are used for biological control of plant diseases. Trichoderma as well as C. rosea mycoparasites efficiently overgrow and kill their fungal prey by using infection structures and by applying lytic enzymes and toxic metabolites. Most of our knowledge on the putative signals and signaling pathways involved in prey recognition and activation of the mycoparasitic response is derived from studies with Trichoderma. These fungi rely on G-protein signaling, the cAMP pathway, and mitogen-activated protein kinase cascades during growth and development as well as during mycoparasitism. The signals being recognized by the mycoparasite may include surface molecules and surface properties as well as secondary metabolites and other small molecules released from the prey. Their exact nature, however, remains elusive so far. Recent genomics-based studies of mycoparasitic fungi of the order Hypocreales, i.e., Trichoderma species, C. rosea, Tolypocladium ophioglossoides, and Escovopsis weberi, revealed not only several gene families with a mycoparasitism-related expansion of gene paralogue numbers, but also distinct differences between the different mycoparasites. We use this information to illustrate the biological principles and molecular basis of necrotrophic mycoparasitism and compare the mycoparasitic strategies of Trichoderma as a "model" mycoparasite with the behavior and special features of C. rosea, T. ophioglossoides, and E. weberi.
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Abstract
ABSTRACT
For the majority of fungal species, the somatic body of an individual is a network of interconnected cells sharing a common cytoplasm and organelles. This syncytial organization contributes to an efficient distribution of resources, energy, and biochemical signals. Cell fusion is a fundamental process for fungal development, colony establishment, and habitat exploitation and can occur between hyphal cells of an individual colony or between colonies of genetically distinct individuals. One outcome of cell fusion is the establishment of a stable heterokaryon, culminating in benefits for each individual via shared resources or being of critical importance for the sexual or parasexual cycle of many fungal species. However, a second outcome of cell fusion between genetically distinct strains is formation of unstable heterokaryons and the induction of a programmed cell death reaction in the heterokaryotic cells. This reaction of nonself rejection, which is termed heterokaryon (or vegetative) incompatibility, is widespread in the fungal kingdom and acts as a defense mechanism against genome exploitation and mycoparasitism. Here, we review the currently identified molecular players involved in the process of somatic cell fusion and its regulation in filamentous fungi. Thereafter, we summarize the knowledge of the molecular determinants and mechanism of heterokaryon incompatibility and place this phenomenon in the broader context of biotropic interactions and immunity.
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Wang M, Zhang M, Li L, Dong Y, Jiang Y, Liu K, Zhang R, Jiang B, Niu K, Fang X. Role of Trichoderma reesei mitogen-activated protein kinases (MAPKs) in cellulase formation. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:99. [PMID: 28435444 PMCID: PMC5397809 DOI: 10.1186/s13068-017-0789-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 04/12/2017] [Indexed: 05/02/2023]
Abstract
BACKGROUND Despite being the most important cellulase producer, the cellulase-regulating carbon source signal transduction processes in Trichoderma reesei are largely unknown. Elucidating these processes is the key for unveiling how external carbon sources regulate cellulase formation, and ultimately for the improvement of cellulase production and biofuel production from lignocellulose. RESULTS In this work, the role of the mitogen-activated protein kinase (MAPK) signal transduction pathways on cellulase formation was investigated. The deletion of yeast FUS3-like tmk1 in T. reesei leads to improved growth and significantly improved cellulase formation. However, tmk1 deletion has no effect on the transcription of cellulase-coding genes. The involvement of the cell wall integrity maintenance governing yeast Slt2-like Tmk2 in cellulase formation was investigated by overexpressing tmk3 in T. reesei Δtmk2 to restore cell wall integrity. Transcriptional analysis found little changes in cellulase-coding genes between T. reesei parent, Δtmk2, and Δtmk2::OEtmk3 strains. Cell wall integrity decreased in T. reesei Δtmk2 over the parent strain and restored in Δtmk2::OEtmk3. Meanwhile, cellulase formation is increased in T. reesei Δtmk2 and then decreased in T. reesei Δtmk2::OEtmk3. CONCLUSIONS These investigations elucidate the role of Tmk1 and Tmk2 on cellulase formation: they repress cellulase formation, respectively, by repressing growth and maintaining cell wall integrity, while neither MAPK regulates the transcription of cellulase-coding genes. This work, together with the previous investigations, suggests that all MAPKs are involved in cellulase formation, while Tmk3 is the only MAPK involved in signal transduction for the regulation of cellulase expression on the transcriptional level.
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Affiliation(s)
- Mingyu Wang
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, China
| | - Meiling Zhang
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, China
| | - Ling Li
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, China
| | - Yanmei Dong
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, China
| | - Yi Jiang
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, China
| | - Kuimei Liu
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, China
| | - Ruiqin Zhang
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, China
| | - Baojie Jiang
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, China
| | - Kangle Niu
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, China
| | - Xu Fang
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, China
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Nox Complex signal and MAPK cascade pathway are cross-linked and essential for pathogenicity and conidiation of mycoparasite Coniothyrium minitans. Sci Rep 2016; 6:24325. [PMID: 27066837 PMCID: PMC4828707 DOI: 10.1038/srep24325] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 03/24/2016] [Indexed: 11/09/2022] Open
Abstract
The NADPH oxidase complex of a sclerotial mycoparasite Coniothyrium minitans, an important biocontrol agent against crop diseases caused by Sclerotinia sclerotiorum, was identified and its functions involved in conidiation and mycoparasitism were studied. Gene knock-out and complementary experiments indicated that CmNox1, but not CmNox2, is necessary for conidiation and parasitism, and its expression could be significantly induced by its host fungus. CmNox1 is regulated by CmRac1-CmNoxR and interacts with CmSlt2, a homolog of Saccharomyces cerevisiae Slt2 encoding cell wall integrity-related MAP kinase. In ΔCmNox1, CmSlt2-GFP fusion protein lost the ability to localize to the cell nucleus accurately. The defect of conidiation in ΔCmRac1 could be partially restored by over-expressing CmSlt2, indicating that CmSlt2 was a downstream regulatory factor of CmNox1 and was involved in conidiation and parasitism. The expressions of mycoparasitism-related genes CmPks1, Cmg1 and CH1 were suppressed in the knock-out mutants of the genes in CmNox1-CmSlt2 signal pathway when cultivated either on PDA. Therefore, our study infers that CmRac1-CmNoxR regulates CmNox1-CmSlt2 pathway in regulating conidiation and pathogenicity of C. minitans.
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Schmoll M, Dattenböck C, Carreras-Villaseñor N, Mendoza-Mendoza A, Tisch D, Alemán MI, Baker SE, Brown C, Cervantes-Badillo MG, Cetz-Chel J, Cristobal-Mondragon GR, Delaye L, Esquivel-Naranjo EU, Frischmann A, Gallardo-Negrete JDJ, García-Esquivel M, Gomez-Rodriguez EY, Greenwood DR, Hernández-Oñate M, Kruszewska JS, Lawry R, Mora-Montes HM, Muñoz-Centeno T, Nieto-Jacobo MF, Nogueira Lopez G, Olmedo-Monfil V, Osorio-Concepcion M, Piłsyk S, Pomraning KR, Rodriguez-Iglesias A, Rosales-Saavedra MT, Sánchez-Arreguín JA, Seidl-Seiboth V, Stewart A, Uresti-Rivera EE, Wang CL, Wang TF, Zeilinger S, Casas-Flores S, Herrera-Estrella A. The Genomes of Three Uneven Siblings: Footprints of the Lifestyles of Three Trichoderma Species. Microbiol Mol Biol Rev 2016; 80:205-327. [PMID: 26864432 PMCID: PMC4771370 DOI: 10.1128/mmbr.00040-15] [Citation(s) in RCA: 121] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The genus Trichoderma contains fungi with high relevance for humans, with applications in enzyme production for plant cell wall degradation and use in biocontrol. Here, we provide a broad, comprehensive overview of the genomic content of these species for "hot topic" research aspects, including CAZymes, transport, transcription factors, and development, along with a detailed analysis and annotation of less-studied topics, such as signal transduction, genome integrity, chromatin, photobiology, or lipid, sulfur, and nitrogen metabolism in T. reesei, T. atroviride, and T. virens, and we open up new perspectives to those topics discussed previously. In total, we covered more than 2,000 of the predicted 9,000 to 11,000 genes of each Trichoderma species discussed, which is >20% of the respective gene content. Additionally, we considered available transcriptome data for the annotated genes. Highlights of our analyses include overall carbohydrate cleavage preferences due to the different genomic contents and regulation of the respective genes. We found light regulation of many sulfur metabolic genes. Additionally, a new Golgi 1,2-mannosidase likely involved in N-linked glycosylation was detected, as were indications for the ability of Trichoderma spp. to generate hybrid galactose-containing N-linked glycans. The genomic inventory of effector proteins revealed numerous compounds unique to Trichoderma, and these warrant further investigation. We found interesting expansions in the Trichoderma genus in several signaling pathways, such as G-protein-coupled receptors, RAS GTPases, and casein kinases. A particularly interesting feature absolutely unique to T. atroviride is the duplication of the alternative sulfur amino acid synthesis pathway.
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Affiliation(s)
- Monika Schmoll
- Austrian Institute of Technology, Department Health and Environment, Bioresources Unit, Tulln, Austria
| | - Christoph Dattenböck
- Austrian Institute of Technology, Department Health and Environment, Bioresources Unit, Tulln, Austria
| | | | | | - Doris Tisch
- Research Division Biotechnology and Microbiology, Institute of Chemical Engineering, TU Wien, Vienna, Austria
| | - Mario Ivan Alemán
- Cinvestav, Department of Genetic Engineering, Irapuato, Guanajuato, Mexico
| | - Scott E Baker
- Pacific Northwest National Laboratory, Richland, Washington, USA
| | - Christopher Brown
- University of Otago, Department of Biochemistry and Genetics, Dunedin, New Zealand
| | | | - José Cetz-Chel
- LANGEBIO, National Laboratory of Genomics for Biodiversity, Cinvestav-Irapuato, Guanajuato, Mexico
| | | | - Luis Delaye
- Cinvestav, Department of Genetic Engineering, Irapuato, Guanajuato, Mexico
| | | | - Alexa Frischmann
- Research Division Biotechnology and Microbiology, Institute of Chemical Engineering, TU Wien, Vienna, Austria
| | | | - Monica García-Esquivel
- LANGEBIO, National Laboratory of Genomics for Biodiversity, Cinvestav-Irapuato, Guanajuato, Mexico
| | | | - David R Greenwood
- The University of Auckland, School of Biological Sciences, Auckland, New Zealand
| | - Miguel Hernández-Oñate
- LANGEBIO, National Laboratory of Genomics for Biodiversity, Cinvestav-Irapuato, Guanajuato, Mexico
| | - Joanna S Kruszewska
- Polish Academy of Sciences, Institute of Biochemistry and Biophysics, Laboratory of Fungal Glycobiology, Warsaw, Poland
| | - Robert Lawry
- Lincoln University, Bio-Protection Research Centre, Lincoln, Canterbury, New Zealand
| | | | | | | | | | | | | | - Sebastian Piłsyk
- Polish Academy of Sciences, Institute of Biochemistry and Biophysics, Laboratory of Fungal Glycobiology, Warsaw, Poland
| | - Kyle R Pomraning
- Pacific Northwest National Laboratory, Richland, Washington, USA
| | - Aroa Rodriguez-Iglesias
- Austrian Institute of Technology, Department Health and Environment, Bioresources Unit, Tulln, Austria
| | | | | | - Verena Seidl-Seiboth
- Research Division Biotechnology and Microbiology, Institute of Chemical Engineering, TU Wien, Vienna, Austria
| | | | | | - Chih-Li Wang
- National Chung-Hsing University, Department of Plant Pathology, Taichung, Taiwan
| | - Ting-Fang Wang
- Academia Sinica, Institute of Molecular Biology, Taipei, Taiwan
| | - Susanne Zeilinger
- Research Division Biotechnology and Microbiology, Institute of Chemical Engineering, TU Wien, Vienna, Austria University of Innsbruck, Institute of Microbiology, Innsbruck, Austria
| | | | - Alfredo Herrera-Estrella
- LANGEBIO, National Laboratory of Genomics for Biodiversity, Cinvestav-Irapuato, Guanajuato, Mexico
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Guo L, Wenner N, Kuldau GA. FvSO regulates vegetative hyphal fusion, asexual growth, fumonisin B1 production, and virulence in Fusarium verticillioides. Fungal Biol 2015; 119:1158-1169. [PMID: 26615739 DOI: 10.1016/j.funbio.2015.08.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 07/24/2015] [Accepted: 08/20/2015] [Indexed: 12/26/2022]
Abstract
Hyphal anastomosis is a hallmark of filamentous fungi and plays vital roles including cellular homoeostasis, interhyphal communication and nutrient translocation. Here we identify a gene, FvSO, in Fusarium verticillioides, a filamentous ascomycete causing maize ear and stalk rot and producing fumonisin mycotoxins. FvSO, like its Neurospora crassa homologue SO, is required for vegetative hyphal fusion. It is also essential for normal vegetative growth, sporulation, and pathogenesis. FvSO encodes a predicted WW domain protein and shares 70 % protein sequence identity with N. crassa SO. FvSO deletion mutants (ΔFvSO) had abnormal distribution of conidia size, and conidia of ΔFvSO germinated much later and slower than wild type. ΔFvSO was deficient in hyphal anastomosis, had slower radial growth and produced less fungal biomass than wild type. ΔFvSO were unable to perform anastomosis, a key feature of filamentous fungi. Interestingly, production of fumonisin B1 by ΔFvSO was significantly reduced compared to wild type. Additionally, ΔFvSO was nonpathogenic to corn ears, stalks and seedlings, likely due to defective growth and development. In conclusion, FvSO is essential for vegetative hyphal fusion and is required for normal vegetative growth and sporulation, normal levels of fumonisin production and pathogenicity in F. verticillioides. The pleiotropic nature of ΔFvSO phenotypes suggests that FvSO is likely involved in certain signalling pathways that regulate multiple cellular functions.
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Affiliation(s)
- Li Guo
- Department of Plant Pathology and Environmental Microbiology, The Pennsylvania State University, University Park, PA 16802, USA
| | - Nancy Wenner
- Department of Plant Pathology and Environmental Microbiology, The Pennsylvania State University, University Park, PA 16802, USA
| | - Gretchen A Kuldau
- Department of Plant Pathology and Environmental Microbiology, The Pennsylvania State University, University Park, PA 16802, USA.
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