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Susanne Zeilinger - One of the best experts on this subject based on the ideXlab platform.
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necrotrophic mycoparasites and their genomes
Microbiology spectrum, 2017Co-Authors: Magnus Karlsson, Lea Atanasova, Dan Funck Jensen, Susanne ZeilingerAbstract: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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Review Article How a Mycoparasite Employs G-Protein Signaling: Using the Example of Trichoderma
2014Co-Authors: Markus Omann, Susanne ZeilingerAbstract:License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Mycoparasitic Trichoderma spp. act as potent biocontrol agents against a number of plant pathogenic fungi, whereupon the mycoparasitic attack includes host recognition followed by infection structure formation and secretion of lytic enzymes and antifungal metabolites leading to the host’s death. Host-derived signals are suggested to be recognized by receptors located on the mycoparasite’s cell surface eliciting an internal signal transduction cascade which results in the transcription of Mycoparasitism-relevant genes. Heterotrimeric G proteins of fungi transmit signals originating from G-protein-coupled receptors mainly to the cAMP and the MAP kinase pathways resulting in regulation of downstream effectors. Components of the G-protein signaling machinery such as Gα subunits and G-protein-coupled receptors were recently shown to play crucial roles in Trichoderma Mycoparasitism as they govern processes such as the production of extracellular cell wall lytic enzymes, the secretion of antifungal metabolites, and the formation of infection structures. 1
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trichoderma plant pathogen interactions advances in genetics of biological control
Indian Journal of Microbiology, 2012Co-Authors: Mala Mukherjee, Prasun K Mukherjee, Benjamin A Horwitz, Christin Zachow, Gabriele Berg, Susanne ZeilingerAbstract:Trichoderma spp. are widely used in agriculture as biofungicides. Induction of plant defense and Mycoparasitism (killing of one fungus by another) are considered to be the most important mechanisms of Trichoderma-mediated biological control. Understanding these mechanisms at the molecular level would help in developing strains with superior biocontrol properties. In this article, we review our current understanding of the genetics of interactions of Trichoderma with plants and plant pathogens.
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the seven transmembrane receptor gpr1 governs processes relevant for the antagonistic interaction of trichoderma atroviride with its host
Microbiology, 2012Co-Authors: Markus Omann, Sylvia Lehner, Carolina Escobar Rodriguez, Kurt Brunner, Susanne ZeilingerAbstract:Mycoparasitic Trichoderma species are applied as biocontrol agents in agriculture to guard plants against fungal diseases. During Mycoparasitism, Trichoderma directly interacts with phytopathogenic fungi, preceded by a specific recognition of the host and resulting in its disarming and killing. In various fungal pathogens, including mycoparasites, signalling via heterotrimeric G proteins plays a major role in regulating pathogenicity-related functions. However, the corresponding receptors involved in the recognition of host-derived signals are largely unknown. Functional characterization of Trichoderma atroviride Gpr1 revealed a prominent role of this seven-transmembrane protein of the cAMP-receptor-like family of fungal G-protein-coupled receptors in the antagonistic interaction with the host fungus and governing of Mycoparasitism-related processes. Silencing of gpr1 led to an avirulent phenotype accompanied by an inability to attach to host hyphae. Furthermore, gpr1-silenced transformants were unable to respond to the presence of living host fungi with the expression of chitinase- and protease-encoding genes. Addition of exogenous cAMP was able to restore host attachment in gpr1-silenced transformants but could not restore mycoparasitic overgrowth. A search for downstream targets of the signalling pathway(s) involving Gpr1 resulted in the isolation of genes encoding e.g. a member of the cyclin-like superfamily and a small secreted cysteine-rich protein. Although silencing of gpr1 caused defects similar to those of mutants lacking the Tga3 Gα protein, no direct interaction between Gpr1 and Tga3 was observed in a split-ubiquitin two-hybrid assay.
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Comparative genome sequence analysis underscores Mycoparasitism as the ancestral life style of Trichoderma.
Genome Biology, 2011Co-Authors: Christian Kubicek, Verena Seidl-seiboth, Susanne Zeilinger, Alfredo Herrera-estrella, Diego Martinez, Irina Druzhinina, Michael Thon, Sergio Casas-flores, Benjamin Horwitz, Prasun MukherjeeAbstract:Background: Mycoparasitism, a lifestyle where one fungus is parasitic on another fungus, has special relevance when the prey is a plant pathogen, providing a strategy for biological control of pests for plant protection. Probably, the most studied biocontrol agents are species of the genus Hypocrea/Trichoderma. Results: Here we report an analysis of the genome sequences of the two biocontrol species Trichoderma atroviride (teleomorph Hypocrea atroviridis) and Trichoderma virens (formerly Gliocladium virens, teleomorph Hypocrea virens), and a comparison with Trichoderma reesei (teleomorph Hypocrea jecorina). These three Trichoderma species display a remarkable conservation of gene order (78 to 96%), and a lack of active mobile elements probably due to repeat-induced point mutation. Several gene families are expanded in the two mycoparasitic species relative to T. reesei or other ascomycetes, and are overrepresented in non-syntenic genome regions. A phylogenetic analysis shows that T. reesei and T. virens are derived relative to T. atroviride. The Mycoparasitism-specific genes thus arose in a common Trichoderma ancestor but were subsequently lost in T. reesei. Conclusions: The data offer a better understanding of Mycoparasitism, and thus enforce the development of improved biocontrol strains for efficient and environmentally friendly protection of plants.
Markus Omann - One of the best experts on this subject based on the ideXlab platform.
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Review Article How a Mycoparasite Employs G-Protein Signaling: Using the Example of Trichoderma
2014Co-Authors: Markus Omann, Susanne ZeilingerAbstract:License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Mycoparasitic Trichoderma spp. act as potent biocontrol agents against a number of plant pathogenic fungi, whereupon the mycoparasitic attack includes host recognition followed by infection structure formation and secretion of lytic enzymes and antifungal metabolites leading to the host’s death. Host-derived signals are suggested to be recognized by receptors located on the mycoparasite’s cell surface eliciting an internal signal transduction cascade which results in the transcription of Mycoparasitism-relevant genes. Heterotrimeric G proteins of fungi transmit signals originating from G-protein-coupled receptors mainly to the cAMP and the MAP kinase pathways resulting in regulation of downstream effectors. Components of the G-protein signaling machinery such as Gα subunits and G-protein-coupled receptors were recently shown to play crucial roles in Trichoderma Mycoparasitism as they govern processes such as the production of extracellular cell wall lytic enzymes, the secretion of antifungal metabolites, and the formation of infection structures. 1
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the seven transmembrane receptor gpr1 governs processes relevant for the antagonistic interaction of trichoderma atroviride with its host
Microbiology, 2012Co-Authors: Markus Omann, Sylvia Lehner, Carolina Escobar Rodriguez, Kurt Brunner, Susanne ZeilingerAbstract:Mycoparasitic Trichoderma species are applied as biocontrol agents in agriculture to guard plants against fungal diseases. During Mycoparasitism, Trichoderma directly interacts with phytopathogenic fungi, preceded by a specific recognition of the host and resulting in its disarming and killing. In various fungal pathogens, including mycoparasites, signalling via heterotrimeric G proteins plays a major role in regulating pathogenicity-related functions. However, the corresponding receptors involved in the recognition of host-derived signals are largely unknown. Functional characterization of Trichoderma atroviride Gpr1 revealed a prominent role of this seven-transmembrane protein of the cAMP-receptor-like family of fungal G-protein-coupled receptors in the antagonistic interaction with the host fungus and governing of Mycoparasitism-related processes. Silencing of gpr1 led to an avirulent phenotype accompanied by an inability to attach to host hyphae. Furthermore, gpr1-silenced transformants were unable to respond to the presence of living host fungi with the expression of chitinase- and protease-encoding genes. Addition of exogenous cAMP was able to restore host attachment in gpr1-silenced transformants but could not restore mycoparasitic overgrowth. A search for downstream targets of the signalling pathway(s) involving Gpr1 resulted in the isolation of genes encoding e.g. a member of the cyclin-like superfamily and a small secreted cysteine-rich protein. Although silencing of gpr1 caused defects similar to those of mutants lacking the Tga3 Gα protein, no direct interaction between Gpr1 and Tga3 was observed in a split-ubiquitin two-hybrid assay.
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how a mycoparasite employs g protein signaling using the example of trichoderma
Journal of Signal Transduction, 2010Co-Authors: Markus Omann, Susanne ZeilingerAbstract:Mycoparasitic Trichoderma spp. act as potent biocontrol agents against a number of plant pathogenic fungi, whereupon the mycoparasitic attack includes host recognition followed by infection structure formation and secretion of lytic enzymes and antifungal metabolites leading to the host's death. Host-derived signals are suggested to be recognized by receptors located on the mycoparasite's cell surface eliciting an internal signal transduction cascade which results in the transcription of Mycoparasitism-relevant genes. Heterotrimeric G proteins of fungi transmit signals originating from G-protein-coupled receptors mainly to the cAMP and the MAP kinase pathways resulting in regulation of downstream effectors. Components of the G-protein signaling machinery such as Gα subunits and G-protein-coupled receptors were recently shown to play crucial roles in Trichoderma Mycoparasitism as they govern processes such as the production of extracellular cell wall lytic enzymes, the secretion of antifungal metabolites, and the formation of infection structures.
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trichoderma biocontrol signal transduction pathways involved in host sensing and Mycoparasitism
Gene regulation and systems biology, 2007Co-Authors: Susanne Zeilinger, Markus OmannAbstract:Fungi of the genus Trichoderma are used as biocontrol agents against several plant pathogenic fungi like Rhizoctonia spp., Pythium spp., Botrytis cinerea and Fusarium spp. which cause both soil-borne and leaf- or flower-borne diseases of agricultural plants. Plant disease control by Trichoderma is based on complex interactions between Trichoderma, the plant pathogen and the plant. Until now, two main components of biocontrol have been identified: direct activity of Trichoderma against the plant pathogen by Mycoparasitism and induced systemic resistance in plants. As the mycoparasitic interaction is host-specific and not merely a contact response, it is likely that signals from the host fungus are recognised by Trichoderma and provoke transcription of Mycoparasitism-related genes. In the last few years examination of signalling pathways underlying Trichoderma biocontrol started and it was shown that heterotrimeric G-proteins and mitogen-activated protein (MAP) kinases affected biocontrol-relevant processes such as the production of hydrolytic enzymes and antifungal metabolites and the formation of infection structures. MAPK signalling was also found to be involved in induction of plant systemic resistance in Trichoderma virens and in the hyperosmotic stress response in Trichoderma harzianum. Analyses of the function of components of the cAMP pathway during Trichoderma biocontrol revealed that Mycoparasitism-associated coiling and chitinase production as well as secondary metabolism are affected by the internal cAMP level; in addition, a cross talk between regulation of light responses and the cAMP signalling pathway was found in Trichoderma atroviride.
Alicia Margarita Godeas - One of the best experts on this subject based on the ideXlab platform.
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clonostachys rosea bafc3874 as a sclerotinia sclerotiorum antagonist mechanisms involved and potential as a biocontrol agent
Journal of Applied Microbiology, 2011Co-Authors: Maria Alejandra Rodriguez, Gabriela Myriam Cabrera, Fabio C Gozzo, Marcos N Eberlin, Alicia Margarita GodeasAbstract:Aims: To establish the modes of action of the antagonistic fungal strain Clonostachys rosea BAFC3874 isolated from suppressive soils against Sclerotinia sclerotiorum and to determine its potential as a biocontrol agent. Methods and Results: The antagonistic activity of C. rosea BAFC3874 was determined in vitro by dual cultures. The strain effectively antagonized S. sclerotiorum in pot-grown lettuce and soybean plants. Antifungal activity assays of C. rosea BAFC3874 grown in culture established that the strain produced antifungal compounds against S. sclerotiorum associated with secondary metabolism. High mycelial growth inhibition coincided with sclerotia production inhibition. The C. rosea strain produced a microheterogeneous mixture of peptides belonging to the peptaibiotic family. Moreover, Mycoparasitism activity was observed in the dual culture. Conclusions: Clonostachys rosea strain BAFC3874 was proved to be an effective antagonist against the aggressive soil-borne pathogen S. sclerotiorum in greenhouse experiments. The main mechanisms involve peptaibiotic metabolite production and Mycoparasitism activity. Significance and Impact of the Study: Clonostachys rosea BAFC3874 may be a good fungal biological control agent against S. sclerotiorum. In addition, we were also able to isolate and identify peptaibols, an unusual family of compounds in this genus of fungi.
Manhong Sun - One of the best experts on this subject based on the ideXlab platform.
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transaldolase gene tal67 enhances the biocontrol activity of clonostachys rosea 67 1 against sclerotinia sclerotiorum
Biochemical and Biophysical Research Communications, 2016Co-Authors: Jingyu Liu, Manhong SunAbstract:Abstract Clonostachys rosea is a promising biocontrol agent that parasitizes various fungal plant pathogens. In this paper, transaldolase gene Tal67 was found to be greatly upregulated in C. rosea isolate 67-1 during Mycoparasitism of Sclerotinia sclerotiorum sclerotia. Quantitative real-time PCR revealed a significant increase in expression at 0–48 h after induction by sclerotia, and the level peaked at 13.9-fold higher than the control at 24 h. Gene disruption led to a decrease in the growth rate of the Tal67-deficient strain ΔTal67 to 5.3 mm/day, which was much lower than the wild type and the complemented strain ΔTal67+ (P
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a perilipin gene from clonostachys rosea f catenulata hl 1 1 is related to sclerotial parasitism
International Journal of Molecular Sciences, 2015Co-Authors: Zhanbin Sun, Zengming Zhong, Manhong SunAbstract:Clonostachys rosea f. catenulata is a promising biocontrol agent against many fungal plant pathogens. To identify Mycoparasitism-related genes from C. rosea f. catenulata, a suppression subtractive hybridization (SSH) cDNA library of C. rosea f. catenulata HL-1-1 that parasitizes the sclerotia of S. sclerotiorum was constructed. 502 clones were sequenced randomly, and thereby 472 expressed sequence tags (ESTs) were identified. Forty-three unigenes were annotated and exhibited similarity to a wide diversity of genes. Quantitative real -time PCR showed that a perilipin-like protein encoding gene, Per3, was up-regulated by 6.6-fold over the control at 96 h under the induction of sclerotia. The full-length sequence of Per3 was obtained via 5' and 3' rapid identification of cDNA ends. Overexpression of Per3 in HL-1-1 significantly enhanced the parasitic ability on sclerotia. The results indicated that Per3 might be involved in the Mycoparasitism of C. rosea f. catenulata HL-1-1. This is the first report of a perilipin as a potential biocontrol gene in mycoparasites. The study provides usefu l insights into the interaction between C. rosea f. catenulata and fungal plant pathogens.
Sabine Gruber - One of the best experts on this subject based on the ideXlab platform.
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comparative transcriptomics reveals different strategies of trichoderma Mycoparasitism
BMC Genomics, 2013Co-Authors: Lea Atanasova, Sabine Gruber, Stephane Le Crom, Fanny Coulpier, Verena Seidlseiboth, Christian P Kubicek, Irina S. DruzhininaAbstract:Trichoderma is a genus of mycotrophic filamentous fungi (teleomorph Hypocrea) which possess a bright variety of biotrophic and saprotrophic lifestyles. The ability to parasitize and/or kill other fungi (Mycoparasitism) is used in plant protection against soil-borne fungal diseases (biological control, or biocontrol). To investigate mechanisms of Mycoparasitism, we compared the transcriptional responses of cosmopolitan opportunistic species and powerful biocontrol agents Trichoderma atroviride and T. virens with tropical ecologically restricted species T. reesei during confrontations with a plant pathogenic fungus Rhizoctonia solani. The three Trichoderma spp. exhibited a strikingly different transcriptomic response already before physical contact with alien hyphae. T. atroviride expressed an array of genes involved in production of secondary metabolites, GH16 s-glucanases, various proteases and small secreted cysteine rich proteins. T. virens, on the other hand, expressed mainly the genes for biosynthesis of gliotoxin, respective precursors and also glutathione, which is necessary for gliotoxin biosynthesis. In contrast, T. reesei increased the expression of genes encoding cellulases and hemicellulases, and of the genes involved in solute transport. The majority of differentially regulated genes were orthologues present in all three species or both in T. atroviride and T. virens, indicating that the regulation of expression of these genes is different in the three Trichoderma spp. The genes expressed in all three fungi exhibited a nonrandom genomic distribution, indicating a possibility for their regulation via chromatin modification. This genome-wide expression study demonstrates that the initial Trichoderma mycotrophy has differentiated into several alternative ecological strategies ranging from parasitism to predation and saprotrophy. It provides first insights into the mechanisms of interactions between Trichoderma and other fungi that may be exploited for further development of biofungicides.
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Self versus non-self: fungal cell wall degradation in Trichoderma.
Microbiology, 2012Co-Authors: Sabine Gruber, Verena Seidl-seibothAbstract:Lysis of the prey’s cell wall is one of the key steps during Mycoparasitism. Genome analysis of two mycoparasitic Trichoderma species, T. atroviride and T. virens, revealed an expanded arsenal of genes encoding enzymes potentially involved in cell wall hydrolysis. Glycoside hydrolase family 18, which contains all fungal chitinases, is the largest family of carbohydrate-active enzymes in mycoparasitic Trichoderma species. However, in addition to their aggressive functions during Mycoparasitism, the roles of chitinases and other cell wall degrading enzymes also include remodelling and recycling of the fungus’s own cell wall. In this review we discuss current knowledge about fungal cell wall degrading enzymes in Trichoderma and how the fungus distinguishes between self- and non-self fungal cell wall degradation. In the past few years, the chitinolytic enzyme machinery of Trichoderma has been used as a model system to address this question. Gene expression profiles of most investigated chitinases indicate an overlap of functions of the respective enzymes and an involvement in both self- and non-self fungal cell wall degradation. Similar sets of enzymes appear to be involved in Mycoparasitism, exogenous chitin decomposition and recycling of the fungus’s own cell wall. Thus, we hypothesize that the regulation of self and non-self fungal cell wall degradation is not due to a speciation of individual chitinases. Rather, we hypothesize that it is regulated by substrate accessibility due to cell wall protection in healthy hyphae vs deprotection during mycoparasitic attack, hyphal ageing and autolysis.
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transcriptomic response of the mycoparasitic fungus trichoderma atroviride to the presence of a fungal prey
BMC Genomics, 2009Co-Authors: Verena Seidl, Sabine Gruber, Susanne Zeilinger, Lifu Song, Erika Lindquist, Alexeji Koptchinskiy, Monika Schmoll, Pedro Martinez, Jibin Sun, Igor V GrigorievAbstract:Background: Combating the action of plant pathogenic microorganisms by mycoparasitic fungi has been announced as an attractive biological alternative to the use of chemical fungicides since two decades. The fungal genus Trichoderma includes a high number of taxa which are able to recognize, combat and finally besiege and kill their prey. Only fragments of the biochemical processes related to this ability have been uncovered so far, however. Results: We analyzed genome-wide gene expression changes during the begin of physical contact between Trichoderma atroviride and two plant pathogens Botrytis cinerea and Rhizoctonia solani, and compared with gene expression patterns of mycelial and conidiating cultures, respectively. About 3000 ESTs, representing about 900 genes, were obtained from each of these three growth conditions. 66 genes, represented by 442 ESTs, were specifically and significantly overexpressed during onset of Mycoparasitism, and the expression of a subset thereof was verified by expression analysis. The upregulated genes comprised 18 KOG groups, but were most abundant from the groups representing posttranslational processing, and amino acid metabolism, and included components of the stress response, reaction to nitrogen shortage, signal transduction and lipid catabolism. Metabolic network analysis confirmed the upregulation of the genes for amino acid biosynthesis and of those involved in the catabolism of lipids and aminosugars. Conclusion: The analysis of the genes overexpressed during the onset of Mycoparasitism in T. atroviride has revealed that the fungus reacts to this condition with several previously undetected physiological reactions. These data enable a new and more comprehensive interpretation of the physiology of Mycoparasitism, and will aid in the selection of traits for improvement of biocontrol strains by recombinant techniques.
