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Calvo AM, Dabholkar A, Wyman EM, Lohmar JM, Cary JW. Beyond morphogenesis and secondary metabolism: function of Velvet proteins and LaeA in fungal pathogenesis. Appl Environ Microbiol 2024:e0081924. [PMID: 39230285 DOI: 10.1128/aem.00819-24] [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: 09/05/2024] Open
Abstract
Velvet proteins, as well as the epigenetic regulator LaeA, are conserved in numerous fungal species, where, in response to environmental cues, they control several crucial cellular processes, including sexual and asexual morphogenesis, secondary metabolism, response to oxidative stress, and virulence. During the last two decades, knowledge of their mechanism of action as well as understanding their functional roles, has greatly increased, particularly in Aspergillus species. Research efforts from multiple groups followed, leading to the characterization of other Velvet and LaeA homologs in species of other fungal genera, including important opportunistic plant and animal pathogens. This review focuses mainly on the current knowledge of the role of Velvet and LaeA function in fungal pathogenesis. Velvet proteins and LaeA are unique to fungi, and for this reason, additional knowledge of these critical regulatory proteins will be important in the development of targeted control strategies to decrease the detrimental impact of fungal pathogens capable of causing disease in plants and animals.
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Affiliation(s)
- Ana M Calvo
- Department of Biological Sciences, Northern Illinois University, DeKalb, Illinois, USA
| | - Apoorva Dabholkar
- Department of Biological Sciences, Northern Illinois University, DeKalb, Illinois, USA
| | - Elizabeth M Wyman
- Department of Biological Sciences, Northern Illinois University, DeKalb, Illinois, USA
| | - Jessica M Lohmar
- Food and Feed Safety Research Unit, USDA/ARS, Southern Regional Research Center, New Orleans, Louisiana, USA
| | - Jeffrey W Cary
- Food and Feed Safety Research Unit, USDA/ARS, Southern Regional Research Center, New Orleans, Louisiana, USA
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Liu Z, Ma K, Zhang X, Song X, Qin Y. Different Putative Methyltransferases Have Different Effects on the Expression Patterns of Cellulolytic Genes. J Fungi (Basel) 2023; 9:1118. [PMID: 37998923 PMCID: PMC10671955 DOI: 10.3390/jof9111118] [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: 10/10/2023] [Revised: 11/07/2023] [Accepted: 11/16/2023] [Indexed: 11/25/2023] Open
Abstract
Putative methyltranferase LaeA and LaeA-like proteins, conserved in many filamentous fungi, regulate fungal growth, development, virulence, the biosynthesis of secondary metabolites, and the production of cellulolytic enzymes. Penicillium oxaliucm is a typical fungus that produces cellulolytic enzymes. In this study, we reported the biological function of eight putative methyltransferases (PoMtr23C/D/E/F/G/H and PoMtr25A/B) containing a methyltransf_23 or methyltransf_25 domain, with a focus on their roles in the production of cellulolytic enzymes. In P. oxalicum, various methyltransferase genes displayed different transcriptional levels. The genes Pomtr23C and Pomtr25A exhibited high transcriptional levels, while Pomtr23D/E/F/G/H and Pomtr25B were transcribed constantly at low levels. The gene deletion mutants (Δmtr23C/D/E/F/G/H and Δmtr25A/B) were constructed. Various mutants have different patterns in cellulolytic enzyme production. Compared to the WT, the largest increase in filter paper activity (FPA, indicating total cellulase activity) was observed in the Δmtr23G mutant, the only mutant with a cellulolytic halo surrounding the colony. Three mutants (Δmtr23C/D and Δmtr25A) also showed increased cellulolytic enzyme production. The Δmtr23E and Δmtr25B mutants displayed decreased FPA activity, while the Δmtr23F and Δmtr23H mutants displayed similar patterns of cellulolytic enzyme production compared with the WT. The assay of transcriptional levels of cellobiohydrolase gene Pocbh1 and β-1,4-endoglucanase Poeg1 supported that higher cellulolytic gene transcription resulted in higher production of cellulolytic enzymes, and vice versa. The transcriptional levels of two transcription factors, activator XlnR and repressor CreA, were measured. The high transcription level of the PoxlnR gene in the Δmtr23D mutant should be one reason for the increased transcription of its cellulolytic enzyme gene. Both XlnR and CreA transcriptional levels increased in the Δmtr23G mutant, but the former showed a more significant increase than the latter, indicating that the activation effect predominated. The PoMtr25A is localized in the nucleus. The catalytic subunit SNF2 of the SWI/SNF chromatin-remodeling complex was found as one of the interacting proteins of PoMtr25A via tandem affinity purification coupled with mass spectrometry. PoMtr25A may affect not only the transcription of repressor CreA but also by recruiting SWI/SNF complexes that affect chromatin structure, thereby regulating the transcription of target genes.
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Affiliation(s)
- Zhongjiao Liu
- National Glycoengineering Research Center, Shandong University, Qingdao 266237, China; (Z.L.); (K.M.); (X.Z.); (X.S.)
| | - Kexuan Ma
- National Glycoengineering Research Center, Shandong University, Qingdao 266237, China; (Z.L.); (K.M.); (X.Z.); (X.S.)
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Xiujun Zhang
- National Glycoengineering Research Center, Shandong University, Qingdao 266237, China; (Z.L.); (K.M.); (X.Z.); (X.S.)
- School of Biological Science and Technology, University of Jinan, Jinan 250024, China
| | - Xin Song
- National Glycoengineering Research Center, Shandong University, Qingdao 266237, China; (Z.L.); (K.M.); (X.Z.); (X.S.)
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Yuqi Qin
- National Glycoengineering Research Center, Shandong University, Qingdao 266237, China; (Z.L.); (K.M.); (X.Z.); (X.S.)
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
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Rubio MB, Monti MM, Gualtieri L, Ruocco M, Hermosa R, Monte E. Trichoderma harzianum Volatile Organic Compounds Regulated by the THCTF1 Transcription Factor Are Involved in Antifungal Activity and Beneficial Plant Responses. J Fungi (Basel) 2023; 9:654. [PMID: 37367590 DOI: 10.3390/jof9060654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 05/30/2023] [Accepted: 06/10/2023] [Indexed: 06/28/2023] Open
Abstract
The transcription factor THCTF1 from Trichoderma harzianum, previously linked to the production of 6-pentyl-2H-pyran-2-one (6-PP) derivatives and antifungal activity against Fusarium oxysporum, has been related in this study to conidiation, production of an array of volatile organic compounds (VOCs) and expression of methyltransferase genes. VOCs emitted by three T. harzianum strains (wild type T34, transformant ΔD1-38 that is disrupted in the Thctf1 gene encoding the transcription factor THCTF1, and ectopic integration transformant ΔJ3-16) were characterized by Proton Transfer Reaction-Quadrupole interface-Time-Of-Flight-Mass Spectrometry (PTR-Qi-TOF-MS). Thctf1 disruption affected the production of numerous VOCs such as the antifungal volatiles 2-pentyl furan and benzaldehyde which were under-emitted, and acetoine, a plant systemic defense inductor, which was over-emitted. Biological assays show that VOCs regulated by THCTF1 are involved in the T. harzianum antifungal activity against Botrytis cinerea and in the beneficial effects leading to Arabidopsis plant development. The VOC blend from the disruptant ΔD1-38: (i) inhibited Arabidopsis seed germination for at least 26 days and (ii) when applied to Arabidopsis seedlings resulted in increased jasmonic acid- and salicylic acid-dependent defenses.
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Affiliation(s)
- María Belén Rubio
- Department of Microbiology and Genetics, Institute for Agribiotechnology Research (CIALE), University of Salamanca, Campus de Villamayor, C/Duero, 12, 37185 Salamanca, Spain
| | - Maurilia Maria Monti
- Institute for Sustainable Plant Protection (CNR-IPSP), Piazzale Enrico Fermi 1, 80055 Naples, Italy
| | - Liberata Gualtieri
- Institute for Sustainable Plant Protection (CNR-IPSP), Piazzale Enrico Fermi 1, 80055 Naples, Italy
| | - Michelina Ruocco
- Institute for Sustainable Plant Protection (CNR-IPSP), Piazzale Enrico Fermi 1, 80055 Naples, Italy
| | - Rosa Hermosa
- Department of Microbiology and Genetics, Institute for Agribiotechnology Research (CIALE), University of Salamanca, Campus de Villamayor, C/Duero, 12, 37185 Salamanca, Spain
| | - Enrique Monte
- Department of Microbiology and Genetics, Institute for Agribiotechnology Research (CIALE), University of Salamanca, Campus de Villamayor, C/Duero, 12, 37185 Salamanca, Spain
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Zhao Z, Gu S, Liu D, Liu D, Chen B, Li J, Tian C. The putative methyltransferase LaeA regulates mycelium growth and cellulase production in Myceliophthora thermophila. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2023; 16:58. [PMID: 37013645 PMCID: PMC10071736 DOI: 10.1186/s13068-023-02313-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 03/28/2023] [Indexed: 04/05/2023]
Abstract
BACKGROUND Filamentous fungi with the ability to use complex carbon sources has been developed as platforms for biochemicals production. Myceliophthora thermophila has been developed as the cell factory to produce lignocellulolytic enzymes and plant biomass-based biofuels and biochemicals in biorefinery. However, low fungal growth rate and cellulose utilization efficiency are significant barriers to the satisfactory yield and productivity of target products, which needs our further exploration and improvement. RESULTS In this study, we comprehensively explored the roles of the putative methyltransferase LaeA in regulating mycelium growth, sugar consumption, and cellulases expression. Deletion of laeA in thermophile fungus Myceliophthora thermophila enhanced mycelium growth and glucose consumption significantly. Further exploration of LaeA regulatory network indicated that multiple growth regulatory factors (GRF) Cre-1, Grf-1, Grf-2, and Grf-3, which act as negative repressors of carbon metabolism, were regulated by LaeA in this fungus. We also determined that phosphoenolpyruvate carboxykinase (PCK) is the core node of the metabolic network related to fungal vegetative growth, of which enhancement partially contributed to the elevated sugar consumption and fungal growth of mutant ΔlaeA. Noteworthily, LaeA participated in regulating the expression of cellulase genes and their transcription regulator. ΔlaeA exhibited 30.6% and 5.5% increases in the peak values of extracellular protein and endo-glucanase activity, respectively, as compared to the WT strain. Furthermore, the global histone methylation assays indicated that LaeA is associated with modulating H3K9 methylation levels. The normal function of LaeA on regulating fungal physiology is dependent on methyltransferase activity. CONCLUSIONS The research presented in this study clarified the function and elucidated the regulatory network of LaeA in the regulation of fungal growth and cellulase production, which will significantly deepen our understanding about the regulation mechanism of LaeA in filamentous fungi and provides the new strategy for improvement the fermentation properties of industrial fungal strain by metabolic engineering.
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Affiliation(s)
- Zhen Zhao
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin, 300308, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Shuying Gu
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin, 300308, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Defei Liu
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin, 300308, China
| | - Dandan Liu
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin, 300308, China
| | - Bingchen Chen
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin, 300308, China
| | - Jingen Li
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.
- National Technology Innovation Center of Synthetic Biology, Tianjin, 300308, China.
| | - Chaoguang Tian
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.
- National Technology Innovation Center of Synthetic Biology, Tianjin, 300308, China.
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Shen Y, Zhang Y, Zhang H, Wang X, Chen J, Li Y. Integrated Transcriptome and Untargeted Metabolomic Analyses Revealed the Role of Methyltransferase Lae1 in the Regulation of Phospholipid Metabolism in Trichoderma atroviride. J Fungi (Basel) 2023; 9:jof9010120. [PMID: 36675941 PMCID: PMC9864869 DOI: 10.3390/jof9010120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 12/29/2022] [Accepted: 01/10/2023] [Indexed: 01/18/2023] Open
Abstract
The putative methyltransferase Lae1 is a global regulator in Trichoderma, which modulates the expression of secondary metabolite gene clusters, possibly via chromatin remodeling. Here we aimed to explore the specific transcription and metabolites profiles regulated by Lae1 in T. atroviride 23. Comparative transcriptomics and metabolome analyses between the lae1 deletion (Mlae1) and over-expressing (Olae1) mutants were performed using RNA sequencing and QTOF-UPLC-MS techniques. In total, 1344 unique differentially expressed genes (DEGs) and 92 metabolites were identified across three strains. The significantly altered metabolic profiles revealed that the lae1 gene modulates central carbon metabolism, amino acid metabolism, secondary metabolism, and phospholipid metabolism. The effects of lae1 on phospholipid metabolism were further explored, and the findings showed that lae1 modulates the composition and function of cell membranes and other metabolic activities, including the phosphotransferase system (PTS) and biosynthesis of secondary metabolites (SM). Phospholipid metabolism is related to energy metabolism, signal transduction, and environmental adaptability of microorganisms. These data showed that Lae1 affects the primary metabolites, phospholipid, as well as the regulation of secondary metabolites in Trichoderma. This study could potentially provoke in-depth investigations of the Lae1-mediated target genes in phospholipid synthesis. The Lae1 may act as a novel target that is associated with disease defense and drug development in the future.
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Affiliation(s)
- Yanxiang Shen
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yiwen Zhang
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Hui Zhang
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xinhua Wang
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China
- State Key Laboratory of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai 200240, China
- Agriculture (South), Ministry of Agriculture, Shanghai 200240, China
| | - Jie Chen
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China
- State Key Laboratory of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai 200240, China
- Agriculture (South), Ministry of Agriculture, Shanghai 200240, China
| | - Yaqian Li
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China
- State Key Laboratory of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai 200240, China
- Agriculture (South), Ministry of Agriculture, Shanghai 200240, China
- Correspondence:
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6
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Yao X, Guo H, Zhang K, Zhao M, Ruan J, Chen J. Trichoderma and its role in biological control of plant fungal and nematode disease. Front Microbiol 2023; 14:1160551. [PMID: 37206337 PMCID: PMC10189891 DOI: 10.3389/fmicb.2023.1160551] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 04/04/2023] [Indexed: 05/21/2023] Open
Abstract
Trichoderma is mainly used to control soil-borne diseases as well as some leaf and panicle diseases of various plants. Trichoderma can not only prevent diseases but also promotes plant growth, improves nutrient utilization efficiency, enhances plant resistance, and improves agrochemical pollution environment. Trichoderma spp. also behaves as a safe, low-cost, effective, eco-friendly biocontrol agent for different crop species. In this study, we introduced the biological control mechanism of Trichoderma in plant fungal and nematode disease, including competition, antibiosis, antagonism, and mycoparasitism, as well as the mechanism of promoting plant growth and inducing plant systemic resistance between Trichoderma and plants, and expounded on the application and control effects of Trichoderma in the control of various plant fungal and nematode diseases. From an applicative point of view, establishing a diversified application technology for Trichoderma is an important development direction for its role in the sustainable development of agriculture.
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Affiliation(s)
- Xin Yao
- College of Agronomy, Guizhou University, Guiyang, China
| | - Hailin Guo
- Science and Technology Innovation Development Center of Bijie City, Bijie, China
| | - Kaixuan Zhang
- Institute of Crop Science, Chinese Academy of Agriculture Science, Beijing, China
| | - Mengyu Zhao
- College of Agronomy, Guizhou University, Guiyang, China
| | - Jingjun Ruan
- College of Agronomy, Guizhou University, Guiyang, China
- *Correspondence: Jingjun Ruan,
| | - Jie Chen
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
- Jie Chen,
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Xiao Z, Zhao Q, Li W, Gao L, Liu G. Strain improvement of Trichoderma harzianum for enhanced biocontrol capacity: Strategies and prospects. Front Microbiol 2023; 14:1146210. [PMID: 37125207 PMCID: PMC10134904 DOI: 10.3389/fmicb.2023.1146210] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 03/20/2023] [Indexed: 05/02/2023] Open
Abstract
In the control of plant diseases, biocontrol has the advantages of being efficient and safe for human health and the environment. The filamentous fungus Trichoderma harzianum and its closely related species can inhibit the growth of many phytopathogenic fungi, and have been developed as commercial biocontrol agents for decades. In this review, we summarize studies on T. harzianum species complex from the perspective of strain improvement. To elevate the biocontrol ability, the production of extracellular proteins and compounds with antimicrobial or plant immunity-eliciting activities need to be enhanced. In addition, resistance to various environmental stressors should be strengthened. Engineering the gene regulatory system has the potential to modulate a variety of biological processes related to biocontrol. With the rapidly developing technologies for fungal genetic engineering, T. harzianum strains with increased biocontrol activities are expected to be constructed to promote the sustainable development of agriculture.
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Affiliation(s)
- Ziyang Xiao
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Qingdao, China
| | - Qinqin Zhao
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Wei Li
- Shanghai Tobacco Group Beijing Cigarette Factory Co., Ltd., Beijing, China
| | - Liwei Gao
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Qingdao, China
- Liwei Gao,
| | - Guodong Liu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
- *Correspondence: Guodong Liu,
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Schalamun M, Schmoll M. Trichoderma - genomes and genomics as treasure troves for research towards biology, biotechnology and agriculture. FRONTIERS IN FUNGAL BIOLOGY 2022; 3:1002161. [PMID: 37746224 PMCID: PMC10512326 DOI: 10.3389/ffunb.2022.1002161] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Accepted: 08/25/2022] [Indexed: 09/26/2023]
Abstract
The genus Trichoderma is among the best studied groups of filamentous fungi, largely because of its high relevance in applications from agriculture to enzyme biosynthesis to biofuel production. However, the physiological competences of these fungi, that led to these beneficial applications are intriguing also from a scientific and ecological point of view. This review therefore summarizes recent developments in studies of fungal genomes, updates on previously started genome annotation efforts and novel discoveries as well as efforts towards bioprospecting for enzymes and bioactive compounds such as cellulases, enzymes degrading xenobiotics and metabolites with potential pharmaceutical value. Thereby insights are provided into genomes, mitochondrial genomes and genomes of mycoviruses of Trichoderma strains relevant for enzyme production, biocontrol and mycoremediation. In several cases, production of bioactive compounds could be associated with responsible genes or clusters and bioremediation capabilities could be supported or predicted using genome information. Insights into evolution of the genus Trichoderma revealed large scale horizontal gene transfer, predominantly of CAZyme genes, but also secondary metabolite clusters. Investigation of sexual development showed that Trichoderma species are competent of repeat induced point mutation (RIP) and in some cases, segmental aneuploidy was observed. Some random mutants finally gave away their crucial mutations like T. reesei QM9978 and QM9136 and the fertility defect of QM6a was traced back to its gene defect. The Trichoderma core genome was narrowed down to 7000 genes and gene clustering was investigated in the genomes of multiple species. Finally, recent developments in application of CRISPR/Cas9 in Trichoderma, cloning and expression strategies for the workhorse T. reesei as well as the use genome mining tools for bioprospecting Trichoderma are highlighted. The intriguing new findings on evolution, genomics and physiology highlight emerging trends and illustrate worthwhile perspectives in diverse fields of research with Trichoderma.
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Affiliation(s)
- Miriam Schalamun
- Center for Health and Bioresources, AIT Austrian Institute of Technology GmbH, Tulln, Austria
| | - Monika Schmoll
- Department of Microbiology and Ecosystem Science, Division of Terrestrial Ecosystem Research, University of Vienna, Vienna, Austria
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Wang L, Liu J, Li X, Lyu X, Liu Z, Zhao H, Jiao X, Zhang W, Xie J, Liu W. A histone H3K9 methyltransferase Dim5 mediates repression of sorbicillinoid biosynthesis in Trichoderma reesei. Microb Biotechnol 2022; 15:2533-2546. [PMID: 35921310 PMCID: PMC9518983 DOI: 10.1111/1751-7915.14103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 06/05/2022] [Indexed: 11/27/2022] Open
Abstract
Sorbicillinoids (also termed yellow pigment) are derived from either marine or terrestrial fungi, exhibit various biological activities and therefore show potential as commercial products for human or animal health. The cellulolytic filamentous fungus Trichoderma reesei is capable to biosynthesize sorbicillinoids, but the underlying regulatory mechanism is not yet completely clear. Herein, we identified a histone H3 lysine 9 (H3K9) methyltransferase, Dim5, in T. reesei. TrDIM5 deletion caused an impaired vegetative growth as well as conidiation, whereas the ∆Trdim5 strain displayed a remarkable increase in sorbicillinoid production. Post TrDIM5 deletion, the transcription of sorbicillinoid biosynthesis‐related (SOR) genes was significantly upregulated with a more open chromatin structure. Intriguingly, hardly any expression changes occurred amongst those genes located on both flanks of the SOR gene cluster. In addition, the assays provided evidence that H3K9 triple methylation (H3K9me3) modification acted as a repressive marker at the SOR gene cluster and thus directly mediated the repression of sorbicillinoid biosynthesis. Transcription factor Ypr1 activated the SOR gene cluster by antagonizing TrDim5‐mediated repression and therefore contributed to forming a relatively more open local chromatin environment, which further facilitated its binding and SOR gene expression. The results of this study will contribute to understanding the intricate regulatory network in sorbicillinoid biosynthesis and facilitate the endowment of T. reesei with preferred features for sorbicillinoid production by genetic engineering.
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Affiliation(s)
- Lei Wang
- Collaborative Innovation Center of Reverse Microbial Etiology, Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Shanxi Medical University, Taiyuan, China
| | - Jialong Liu
- Collaborative Innovation Center of Reverse Microbial Etiology, Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Shanxi Medical University, Taiyuan, China
| | - Xiaotong Li
- Collaborative Innovation Center of Reverse Microbial Etiology, Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Shanxi Medical University, Taiyuan, China
| | - Xinxing Lyu
- Institute of Basic Medicine, Shandong First Medical University&Shandong Academy of Medical Sciences, Jinan, China
| | - Zhizhen Liu
- Collaborative Innovation Center of Reverse Microbial Etiology, Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Shanxi Medical University, Taiyuan, China
| | - Hong Zhao
- Collaborative Innovation Center of Reverse Microbial Etiology, Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Shanxi Medical University, Taiyuan, China
| | - Xiangying Jiao
- Collaborative Innovation Center of Reverse Microbial Etiology, Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Shanxi Medical University, Taiyuan, China
| | - Weixin Zhang
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, China
| | - Jun Xie
- Collaborative Innovation Center of Reverse Microbial Etiology, Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Shanxi Medical University, Taiyuan, China
| | - Weifeng Liu
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, China
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11
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Dou K, Pang G, Cai F, Chenthamara K, Zhang J, Liu H, Druzhinina IS, Chen J. Functional Genetics of Trichoderma Mycoparasitism. Fungal Biol 2022. [DOI: 10.1007/978-3-030-91650-3_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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12
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Sarrocco S, Vicente I, Staropoli A, Vinale F. Genes Involved in the Secondary Metabolism of Trichoderma and the Biochemistry of These Compounds. Fungal Biol 2022. [DOI: 10.1007/978-3-030-91650-3_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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13
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Ding Z, Wang X, Kong FD, Huang HM, Zhao YN, Liu M, Wang ZP, Han J. Overexpression of Global Regulator Talae1 Leads to the Discovery of New Antifungal Polyketides From Endophytic Fungus Trichoderma afroharzianum. Front Microbiol 2020; 11:622785. [PMID: 33424824 PMCID: PMC7785522 DOI: 10.3389/fmicb.2020.622785] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 12/04/2020] [Indexed: 12/12/2022] Open
Abstract
Transcription regulation caused by global regulators exerts important effects on fungal secondary metabolism. By overexpression of the global regulator Talae1 in a Ficus elastica-associated fungus Trichoderma afroharzianum, two structurally new polyketides (1 and 2) that were newly produced in the transformant were isolated and identified. Their structures, including the absolute configurations, were elucidated through a combination of high resolution mass spectrometer (HRMS), NMR, and electronic circular dichroism (ECD) calculations. The growth inhibitory activities of compounds 1 and 2 were evaluated against four bacteria and six plant-pathogenic fungi. Compound 1 showed the highest antifungal activity against Botrytis cinerea and Fusarium oxysporum f. sp. nicotianae with MIC of 8 μg/ml. To the best of our knowledge, this is the first study to report on the application of the global regulator in T. afroharzianum to activate the biosynthesis of bioactive secondary metabolites.
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Affiliation(s)
- Zhuang Ding
- Institute of BioPharmaceutical Research, Liaocheng University, Liaocheng, China
| | - Xiao Wang
- Institute of BioPharmaceutical Research, Liaocheng University, Liaocheng, China
| | - Fan-Dong Kong
- Hainan Key Laboratory for Research and Development of Natural Product From Li Folk Medicine, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agriculture Sciences, Haikou, China
| | - Hui-Ming Huang
- School of Life Sciences, Liaocheng University, Liaocheng, China
| | - Yan-Na Zhao
- Institute of BioPharmaceutical Research, Liaocheng University, Liaocheng, China
| | - Min Liu
- Institute of BioPharmaceutical Research, Liaocheng University, Liaocheng, China
| | - Zheng-Ping Wang
- Institute of BioPharmaceutical Research, Liaocheng University, Liaocheng, China
| | - Jun Han
- Institute of BioPharmaceutical Research, Liaocheng University, Liaocheng, China
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14
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Moreno-Ruiz D, Fuchs A, Missbach K, Schuhmacher R, Zeilinger S. Influence of Different Light Regimes on the Mycoparasitic Activity and 6-Pentyl-α-pyrone Biosynthesis in Two Strains of Trichoderma atroviride. Pathogens 2020; 9:pathogens9100860. [PMID: 33096850 PMCID: PMC7589932 DOI: 10.3390/pathogens9100860] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 10/14/2020] [Accepted: 10/19/2020] [Indexed: 01/09/2023] Open
Abstract
The ascomycete Trichoderma atroviride is well known for its mycoparasitic lifestyle. Similar to other organisms, light is an important cue for T. atroviride. However, besides triggering of conidiation, little is known on the physiological responses of T. atroviride to light. In this study, we analyzed how cultivation under different light wavelengths and regimes impacted the behavior of two T. atroviride wild-type strains: IMI206040 and P1. While colony extension of both strains was slightly affected by light, massive differences in their photoconidation responses became evident. T. atroviride P1 colonies conidiated under all conditions tested including growth in complete darkness, while IMI206040 required white, blue or green light to trigger asexual reproduction. Interestingly, deletion of the stress-activated MAP kinase-encoding gene tmk3 abolished the ability of strain P1 to conidiate in red and yellow light as well as in darkness. Furthermore, light-dependent differences in the mycoparasitic activity and in the biosynthesis of the secondary metabolite 6-pentyl-α-pyrone (6-PP) became evident. 6-PP production was highest upon dark incubation, while light, especially exposure to white light as light/dark cycles, had an inhibitory effect on its biosynthesis. We conclude that the response of T. atroviride to light is strain-dependent and impacts differentiation, mycoparasitism, and 6-PP production; hence, this should be considered in experiments testing the mycoparasitic activity of these fungi.
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Affiliation(s)
- Dubraska Moreno-Ruiz
- Department of Microbiology, University of Innsbruck, 6020 Innsbruck, Austria; (D.M.-R.); (A.F.)
| | - Alessandro Fuchs
- Department of Microbiology, University of Innsbruck, 6020 Innsbruck, Austria; (D.M.-R.); (A.F.)
| | - Kristina Missbach
- Department of Agrobiotechnology (IFA-Tulln), University of Natural Resources and Life Sciences Vienna (BOKU), 1180 Tulln, Austria; (K.M.); (R.S.)
| | - Rainer Schuhmacher
- Department of Agrobiotechnology (IFA-Tulln), University of Natural Resources and Life Sciences Vienna (BOKU), 1180 Tulln, Austria; (K.M.); (R.S.)
| | - Susanne Zeilinger
- Department of Microbiology, University of Innsbruck, 6020 Innsbruck, Austria; (D.M.-R.); (A.F.)
- Correspondence:
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15
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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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16
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Shi JC, Shi WL, Zhou YR, Chen XL, Zhang YZ, Zhang X, Zhang WX, Song XY. The Putative Methyltransferase TlLAE1 Is Involved in the Regulation of Peptaibols Production in the Biocontrol Fungus Trichoderma longibrachiatum SMF2. Front Microbiol 2020; 11:1267. [PMID: 32612590 PMCID: PMC7307461 DOI: 10.3389/fmicb.2020.01267] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Accepted: 05/18/2020] [Indexed: 11/30/2022] Open
Abstract
The biocontrol fungus Trichoderma longibrachiatum SMF2 secretes a large quantity of peptaibols that have been shown to have a range of biological activities and therefore great application values. However, the mechanism of the regulatory expression of peptaibols is still unclear. The putative methyltransferase LaeA/LAE1 is a global regulator involved in the biosynthesis of some secondary metabolites in filamentous fungi. In this study, we demonstrated that the ortholog of LaeA/LAE1 in the biocontrol fungus T. longibrachiatum SMF2, TlLAE1, plays an important role in the regulation of peptaibols production. Deletion of Tllae1 resulted in a slight negative impact on mycelial growth, and a significant defect in conidial production. Deletion of Tllae1 also compromised the production of peptaibols to a large degree. Further analyses indicated that this defect occurred at the transcriptional level of the two synthetases-encoding genes, tlx1 and tlx2, which are responsible for peptaibols production. By contrast, constitutive expression of Tllae1 in T. longibrachiatum SMF2 led to 2-fold increased peptaibols production, suggesting that this is a strategy to improve peptaibols production in Trichoderma fungi. These results demonstrate the important role of LAE1 in the regulation of peptaibols production in T. longibrachiatum SMF2.
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Affiliation(s)
- Jin-Chao Shi
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, China
| | - Wei-Ling Shi
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, China
| | - Yan-Rong Zhou
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, China
| | - Xiu-Lan Chen
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, China
| | - Yu-Zhong Zhang
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, China.,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.,College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Xia Zhang
- Department of Molecular Biology, Qingdao Vland Biotech Inc., Qingdao, China
| | - Wei-Xin Zhang
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, China
| | - Xiao-Yan Song
- State Key Laboratory of Microbial Technology, Marine Biotechnology Research Center, Shandong University, Qingdao, China
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17
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Abstract
Fungi are rich sources of secondary metabolites of pharmaceutical importance, such as antibiotics, antitumor agents, and immunosuppressants, as well as of harmful toxins. Secondary metabolites play important roles in the development and pathogenesis of fungi. LaeA is a global regulator of secondary metabolism and was originally reported in Aspergillus nidulans; however, its role in secondary metabolism in Magnaporthe oryzae has not yet been reported. Here, we investigated the role of a gene homologous to LAEA (loss of AflR expression) of Aspergillus spp. in Magnaporthe oryzae, named M. oryzaeLAEA (MoLAEA). Studies on MoLAEA overexpression and knockdown strains have suggested that this gene acts as a negative regulator of sporulation and melanin synthesis. However, it is not involved in the growth and pathogenesis of M. oryzae Transcriptomic data indicated that MoLAEA regulated genes involved in secondary metabolism. Interestingly, we observed (for the first time, to our knowledge) that this gene is involved in benzylpenicillin (penicillin G) synthesis in M. oryzae Overexpression of MoLAEA increased penicillin G production, whereas the silenced strain showed a complete absence of penicillin G compared to its presence in the wild type. We also observed that MoLaeA interacted with MoVeA, a velvet family protein involved in fungal development and secondary metabolism, in the nucleus. This study showed that though MoLAEA may not make any contribution in rice blast fungal pathogenesis, it regulates secondary metabolism in M. oryzae and thus can be further studied for identifying other new uncharacterized metabolites in this fungus.IMPORTANCEM. oryzae causes blast disease, the most serious disease of cultivated rice affecting global rice production. The genome of M. oryzae has been shown to have a number of genes involved in secondary metabolism, but most of them are uncharacterized. In fact, compared to studies of other filamentous fungi, hardly any work has been done on secondary metabolism in M. oryzae It is shown here (for the first time, to our knowledge) that penicillin G is being synthesized in M. oryzae and that MoLAEA is involved in this process. This is the first step in understanding the penicillin G biosynthesis pathway in M. oryzae This study also unraveled the details of how MoLaeA works by forming a nuclear complex with MoVeA in M. oryzae, thus indicating functional conservation of such a gene across filamentous fungi. All these findings open up avenues for more relevant investigations on the genetic regulation of secondary metabolism in M. oryzae.
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18
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Fanelli F, Liuzzi VC, Logrieco AF, Altomare C. Genomic characterization of Trichoderma atrobrunneum (T. harzianum species complex) ITEM 908: insight into the genetic endowment of a multi-target biocontrol strain. BMC Genomics 2018; 19:662. [PMID: 30200883 PMCID: PMC6131884 DOI: 10.1186/s12864-018-5049-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 08/31/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND So far, biocontrol agent selection has been performed mainly by time consuming in vitro confrontation tests followed by extensive trials in greenhouse and field. An alternative approach is offered by application of high-throughput techniques, which allow extensive screening and comparison among strains for desired genetic traits. In the genus Trichoderma, the past assignments of particular features or strains to one species need to be reconsidered according to the recent taxonomic revisions. Here we present the genome of a biocontrol strain formerly known as Trichoderma harzianum ITEM 908, which exhibits both growth promoting capabilities and antagonism against different fungal pathogens, including Fusarium graminearum, Rhizoctonia solani, and the root-knot nematode Meloidogyne incognita. By genomic analysis of ITEM 908 we investigated the occurrence and the relevance of genes associated to biocontrol and stress tolerance, providing a basis for future investigation aiming to unravel the complex relationships between genomic endowment and exhibited activities of this strain. RESULTS The MLST analysis of ITS-TEF1 concatenated datasets reclassified ITEM 908 as T. atrobrunneum, a species recently described within the T. harzianum species complex and phylogenetically close to T. afroharzianum and T. guizhouense. Genomic analysis revealed the presence of a broad range of genes encoding for carbohydrate active enzymes (CAZYmes), proteins involved in secondary metabolites production, peptaboils, epidithiodioxopiperazines and siderophores potentially involved in parasitism, saprophytic degradation as well as in biocontrol and antagonistic activities. This abundance is comparable to other Trichoderma spp. in the T. harzianum species complex, but broader than in other biocontrol species and in the species T. reesei, known for its industrial application in cellulase production. Comparative analysis also demonstrated similar genomic organization of major secondary metabolites clusters, as in other Trichoderma species. CONCLUSIONS Reported data provide a contribution to a deeper understanding of the mode of action and identification of activity-specific genetic markers useful for selection and improvement of biocontrol strains. This work will also enlarge the availability of genomic data to perform comparative studies with the aim to correlate phenotypic differences with genetic diversity of Trichoderma species.
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Affiliation(s)
- Francesca Fanelli
- Institute of Sciences of Food Production, National Research Council, Bari, Italy
| | - Vania Cosma Liuzzi
- Institute of Sciences of Food Production, National Research Council, Bari, Italy
| | | | - Claudio Altomare
- Institute of Sciences of Food Production, National Research Council, Bari, Italy
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19
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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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20
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Jain S, Sekonyela R, Knox BP, Palmer JM, Huttenlocher A, Kabbage M, Keller NP. Selenate sensitivity of a laeA mutant is restored by overexpression of the bZIP protein MetR in Aspergillus fumigatus. Fungal Genet Biol 2018; 117:1-10. [PMID: 29753128 PMCID: PMC6064392 DOI: 10.1016/j.fgb.2018.05.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2018] [Revised: 05/07/2018] [Accepted: 05/08/2018] [Indexed: 02/06/2023]
Abstract
LaeA is a conserved global regulator of secondary metabolism and development in filamentous fungi. Examination of Aspergillus fumigatus transcriptome data of laeA deletion mutants have been fruitful in identifying genes and molecules contributing to the laeA mutant phenotype. One of the genes significantly down regulated in A. fumigatus ΔlaeA is metR, encoding a bZIP DNA binding protein required for sulfur and methionine metabolism in fungi. LaeA and MetR deletion mutants exhibit several similarities including down regulation of sulfur assimilation and methionine metabolism genes and ability to grow on the toxic sulfur analog, sodium selenate. However, unlike ΔmetR, ΔlaeA strains are able to grow on sulfur, sulfite, and cysteine. To examine if any parameter of the ΔlaeA phenotype is due to decreased metR expression, an over-expression allele (OE::metR) was placed in a ΔlaeA background. The OE::metR allele could not significantly restore expression of MetR regulated genes in ΔlaeA but did restore sensitivity to sodium selenate. In A. nidulans a second bZIP protein, MetZ, also regulates sulfur and methionine metabolism genes. However, addition of an OE::metZ construct to the A. fumigatus ΔlaeA OE::metR strain still was unable to rescue the ΔlaeA phenotype to wildtype with regards gliotoxin synthesis and virulence in a zebrafish aspergillosis model.
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Affiliation(s)
- Sachin Jain
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, WI 53706, United States
| | - Relebohile Sekonyela
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, United States
| | - Benjamin P Knox
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI 53706, United States
| | - Jonathan M Palmer
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, WI 53706, United States
| | - Anna Huttenlocher
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI 53706, United States
| | - Mehdi Kabbage
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, WI 53706, United States
| | - Nancy P Keller
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, United States; Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI 53706, United States.
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21
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Riquelme M, Aguirre J, Bartnicki-García S, Braus GH, Feldbrügge M, Fleig U, Hansberg W, Herrera-Estrella A, Kämper J, Kück U, Mouriño-Pérez RR, Takeshita N, Fischer R. Fungal Morphogenesis, from the Polarized Growth of Hyphae to Complex Reproduction and Infection Structures. Microbiol Mol Biol Rev 2018; 82:e00068-17. [PMID: 29643171 PMCID: PMC5968459 DOI: 10.1128/mmbr.00068-17] [Citation(s) in RCA: 183] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Filamentous fungi constitute a large group of eukaryotic microorganisms that grow by forming simple tube-like hyphae that are capable of differentiating into more-complex morphological structures and distinct cell types. Hyphae form filamentous networks by extending at their tips while branching in subapical regions. Rapid tip elongation requires massive membrane insertion and extension of the rigid chitin-containing cell wall. This process is sustained by a continuous flow of secretory vesicles that depends on the coordinated action of the microtubule and actin cytoskeletons and the corresponding motors and associated proteins. Vesicles transport cell wall-synthesizing enzymes and accumulate in a special structure, the Spitzenkörper, before traveling further and fusing with the tip membrane. The place of vesicle fusion and growth direction are enabled and defined by the position of the Spitzenkörper, the so-called cell end markers, and other proteins involved in the exocytic process. Also important for tip extension is membrane recycling by endocytosis via early endosomes, which function as multipurpose transport vehicles for mRNA, septins, ribosomes, and peroxisomes. Cell integrity, hyphal branching, and morphogenesis are all processes that are largely dependent on vesicle and cytoskeleton dynamics. When hyphae differentiate structures for asexual or sexual reproduction or to mediate interspecies interactions, the hyphal basic cellular machinery may be reprogrammed through the synthesis of new proteins and/or the modification of protein activity. Although some transcriptional networks involved in such reprogramming of hyphae are well studied in several model filamentous fungi, clear connections between these networks and known determinants of hyphal morphogenesis are yet to be established.
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Affiliation(s)
- Meritxell Riquelme
- Department of Microbiology, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, Baja California, Mexico
| | - Jesús Aguirre
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de Mexico, Mexico City, Mexico
| | - Salomon Bartnicki-García
- Department of Microbiology, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, Baja California, Mexico
| | - Gerhard H Braus
- Department of Molecular Microbiology and Genetics and Goettingen Center for Molecular Biosciences (GZMB), University of Goettingen, Goettingen, Germany
| | - Michael Feldbrügge
- Institute for Microbiology, Heinrich Heine University Düsseldorf, Cluster of Excellence on Plant Sciences, Düsseldorf, Germany
| | - Ursula Fleig
- Institute for Functional Genomics of Microorganisms, Heinrich Heine University Düsseldorf, Cluster of Excellence on Plant Sciences, Düsseldorf, Germany
| | - Wilhelm Hansberg
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de Mexico, Mexico City, Mexico
| | - Alfredo Herrera-Estrella
- Laboratorio Nacional de Genómica para la Biodiversidad, Centro de Investigación y de Estudios Avanzados del IPN, Irapuato, Mexico
| | - Jörg Kämper
- Karlsruhe Institute of Technology-South Campus, Institute for Applied Biosciences, Karlsruhe, Germany
| | - Ulrich Kück
- Ruhr University Bochum, Lehrstuhl für Allgemeine und Molekulare Botanik, Bochum, Germany
| | - Rosa R Mouriño-Pérez
- Department of Microbiology, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, Baja California, Mexico
| | - Norio Takeshita
- University of Tsukuba, Faculty of Life and Environmental Sciences, Tsukuba, Japan
| | - Reinhard Fischer
- Karlsruhe Institute of Technology-South Campus, Institute for Applied Biosciences, Karlsruhe, Germany
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22
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Dattenböck C, Tisch D, Schuster A, Monroy AA, Hinterdobler W, Schmoll M. Gene regulation associated with sexual development and female fertility in different isolates of Trichoderma reesei. Fungal Biol Biotechnol 2018; 5:9. [PMID: 29785273 PMCID: PMC5952832 DOI: 10.1186/s40694-018-0055-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 04/12/2018] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Trichoderma reesei is one of the most frequently used filamentous fungi in industry for production of homologous and heterologous proteins. The ability to use sexual crossing in this fungus was discovered several years ago and opens up new perspectives for industrial strain improvement and investigation of gene regulation. RESULTS Here we investigated the female sterile strain QM6a in comparison to the fertile isolate CBS999.97 and backcrossed derivatives of QM6a, which have regained fertility (FF1 and FF2 strains) in both mating types under conditions of sexual development. We found considerable differences in gene regulation between strains with the CBS999.97 genetic background and the QM6a background. Regulation patterns of QM6a largely clustered with the backcrossed FF1 and FF2 strains. Differential regulation between QM6a and FF1/FF2 as well as clustering of QM6a patterns with those of CBS999.97 strains was also observed. Consistent mating type dependent regulation was limited to mating type genes and those involved in pheromone response, but included also nta1 encoding a putative N-terminal amidase previously not associated with development. Comparison of female sterile QM6a with female fertile strains showed differential expression in genes encoding several transcription factors, metabolic genes and genes involved in secondary metabolism. CONCLUSIONS Evaluation of the functions of genes specifically regulated under conditions of sexual development and of genes with highest levels of transcripts under these conditions indicated a relevance of secondary metabolism for sexual development in T. reesei. Among others, the biosynthetic genes of the recently characterized SOR cluster are in this gene group. However, these genes are not essential for sexual development, but rather have a function in protection and defence against competitors during reproduction.
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Affiliation(s)
- Christoph Dattenböck
- Center for Health and Bioresources, AIT Austrian Institute of Technology GmbH, Konrad Lorenz Straße 24, 3430 Tulln, Austria
| | - Doris Tisch
- Institute of Chemical Engineering, Research Area Molecular Biotechnology, TU Wien, 1060 Vienna, Austria
| | - Andre Schuster
- Institute of Chemical Engineering, Research Area Molecular Biotechnology, TU Wien, 1060 Vienna, Austria
| | - Alberto Alonso Monroy
- Center for Health and Bioresources, AIT Austrian Institute of Technology GmbH, Konrad Lorenz Straße 24, 3430 Tulln, Austria
| | - Wolfgang Hinterdobler
- Center for Health and Bioresources, AIT Austrian Institute of Technology GmbH, Konrad Lorenz Straße 24, 3430 Tulln, Austria
| | - Monika Schmoll
- Center for Health and Bioresources, AIT Austrian Institute of Technology GmbH, Konrad Lorenz Straße 24, 3430 Tulln, Austria
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23
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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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Barkal LJ, Procknow CL, Álvarez-García YR, Niu M, Jiménez-Torres JA, Brockman-Schneider RA, Gern JE, Denlinger LC, Theberge AB, Keller NP, Berthier E, Beebe DJ. Microbial volatile communication in human organotypic lung models. Nat Commun 2017; 8:1770. [PMID: 29176665 PMCID: PMC5701243 DOI: 10.1038/s41467-017-01985-4] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2017] [Accepted: 10/30/2017] [Indexed: 12/13/2022] Open
Abstract
We inhale respiratory pathogens continuously, and the subsequent signaling events between host and microbe are complex, ultimately resulting in clearance of the microbe, stable colonization of the host, or active disease. Traditional in vitro methods are ill-equipped to study these critical events in the context of the lung microenvironment. Here we introduce a microscale organotypic model of the human bronchiole for studying pulmonary infection. By leveraging microscale techniques, the model is designed to approximate the structure of the human bronchiole, containing airway, vascular, and extracellular matrix compartments. To complement direct infection of the organotypic bronchiole, we present a clickable extension that facilitates volatile compound communication between microbial populations and the host model. Using Aspergillus fumigatus, a respiratory pathogen, we characterize the inflammatory response of the organotypic bronchiole to infection. Finally, we demonstrate multikingdom, volatile-mediated communication between the organotypic bronchiole and cultures of Aspergillus fumigatus and Pseudomonas aeruginosa.
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Affiliation(s)
- Layla J Barkal
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA.,Carbone Cancer Center, University of Wisconsin-Madison, Madison, WI, 53705, USA
| | - Clare L Procknow
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | | | - Mengyao Niu
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - José A Jiménez-Torres
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA.,Carbone Cancer Center, University of Wisconsin-Madison, Madison, WI, 53705, USA
| | - Rebecca A Brockman-Schneider
- Department of Pediatrics, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, 53705, USA
| | - James E Gern
- Department of Pediatrics, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, 53705, USA
| | - Loren C Denlinger
- Department of Medicine, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, 53705, USA
| | - Ashleigh B Theberge
- Department of Chemistry, University of Washington, Seattle, WA, 98195, USA.,Department of Urology, University of Washington School of Medicine, Seattle, WA, 98195, USA
| | - Nancy P Keller
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, 53706, USA.,Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Erwin Berthier
- Department of Chemistry, University of Washington, Seattle, WA, 98195, USA. .,Tasso Inc., Seattle, WA, 98119, USA.
| | - David J Beebe
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA. .,Carbone Cancer Center, University of Wisconsin-Madison, Madison, WI, 53705, USA.
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25
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Lysøe E, Dees MW, Brurberg MB. A Three-Way Transcriptomic Interaction Study of a Biocontrol Agent (Clonostachys rosea), a Fungal Pathogen (Helminthosporium solani), and a Potato Host (Solanum tuberosum). MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2017; 30:646-655. [PMID: 28585451 DOI: 10.1094/mpmi-03-17-0062-r] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Helminthosporium solani causes silver scurf, which affects the quality of potato. The biocontrol agent Clonostachys rosea greatly limited the severity of silver scurf symptoms and amount of H. solani genomic DNA in laboratory experiments. Transcriptomic analysis during interaction showed that H. solani gene expression was highly reduced when coinoculated with the biocontrol agent C. rosea, whereas gene expression of C. rosea was clearly boosted as a response to the pathogen. The most notable upregulated C. rosea genes were those encoding proteins involved in cellular response to oxidative stress, proteases, G-protein signaling, and the methyltransferase LaeA. The most notable potato response to both fungi was downregulation of defense-related genes and mitogen-activated protein kinase kinase kinases. At a later stage, this shifted, and most potato defense genes were turned on, especially those involved in terpenoid biosynthesis when H. solani was present. Some biocontrol-activated defense-related genes in potato were upregulated during early interaction with C. rosea alone that were not triggered by H. solani alone. Our results indicate that the reductions of silver scurf using C. rosea are probably due to a combination of mechanisms, including mycoparasitism, biocontrol-activated stimulation of plant defense mechanisms, microbial competition for nutrients, space, and antibiosis.
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Affiliation(s)
- Erik Lysøe
- 1 Norwegian Institute of Bioeconomy Research, Division of Biotechnology and Plant Health, Høgskoleveien 7, 1430 Ås, Norway; and
| | - Merete W Dees
- 1 Norwegian Institute of Bioeconomy Research, Division of Biotechnology and Plant Health, Høgskoleveien 7, 1430 Ås, Norway; and
| | - May Bente Brurberg
- 1 Norwegian Institute of Bioeconomy Research, Division of Biotechnology and Plant Health, Høgskoleveien 7, 1430 Ås, Norway; and
- 2 Norwegian University of Life Sciences, Department of Plant Sciences, 1432 Ås, Norway
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26
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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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27
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Benocci T, Aguilar-Pontes MV, Zhou M, Seiboth B, de Vries RP. Regulators of plant biomass degradation in ascomycetous fungi. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:152. [PMID: 28616076 PMCID: PMC5468973 DOI: 10.1186/s13068-017-0841-x] [Citation(s) in RCA: 125] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 06/06/2017] [Indexed: 05/05/2023]
Abstract
Fungi play a major role in the global carbon cycle because of their ability to utilize plant biomass (polysaccharides, proteins, and lignin) as carbon source. Due to the complexity and heterogenic composition of plant biomass, fungi need to produce a broad range of degrading enzymes, matching the composition of (part of) the prevalent substrate. This process is dependent on a network of regulators that not only control the extracellular enzymes that degrade the biomass, but also the metabolic pathways needed to metabolize the resulting monomers. This review will summarize the current knowledge on regulation of plant biomass utilization in fungi and compare the differences between fungal species, focusing in particular on the presence or absence of the regulators involved in this process.
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Affiliation(s)
- Tiziano Benocci
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
| | - Maria Victoria Aguilar-Pontes
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
| | - Miaomiao Zhou
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
| | - Bernhard Seiboth
- Research Area Biochemical Technology, Institute of Chemical and Biological Engineering, TU Wien, 1060 Vienna, Austria
| | - Ronald P. de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
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28
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Zhang X, Zhu Y, Bao L, Gao L, Yao G, Li Y, Yang Z, Li Z, Zhong Y, Li F, Yin H, Qu Y, Qin Y. Putative methyltransferase LaeA and transcription factor CreA are necessary for proper asexual development and controlling secondary metabolic gene cluster expression. Fungal Genet Biol 2016; 94:32-46. [PMID: 27387217 DOI: 10.1016/j.fgb.2016.07.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Revised: 06/30/2016] [Accepted: 07/03/2016] [Indexed: 11/28/2022]
Abstract
The morphological development of fungi is a complex process and is often coupled with secondary metabolite production. In this study, we assessed the function of putative methyltransferase LaeA and transcription factor CreA in controlling asexual development and secondary metabolic gene cluster expression in Penicillium oxalicum. The deletion of laeA (ΔlaeA) impaired the conidiation in P. oxalicum, with a downregulated expression of brlA. Overexpression of P. oxalicum brlA in ΔlaeA could upregulate brlA and abaA remarkably, but could not rescue the conidiation defect; therefore, brlA and abaA expression were necessary but not sufficient for conidiation. Deletion of creA in ΔlaeA background (ΔlaeAΔcreA) blocked conidiation with a white fluffy phenotype. Nutrient-rich medium could not rescue developmental defects in ΔlaeAΔcreA mutant but could rescue defects in ΔlaeA. Expression of 10 genes, namely, albA/wA, abrB/yA, arpA, aygA, arpA-like, arpB, arpB-like, rodA, rodA-like, and rodB, for pigmentation and spore wall protein genes was silenced in ΔlaeAΔcreA, whereas only six of them were downregulated in ΔlaeA. Among the 28 secondary metabolism gene clusters in P. oxalicum, four secondary metabolism gene clusters were silenced in ΔlaeA and two were also silenced in ΔbrlA mutant. A total of 10 physically linked and coregulated genes were distributed over five chromosomes in ΔlaeA. Six of these genes were located in subtelomeric regions, thus demonstrating a positional bias for LaeA-regulated clusters toward subtelomeric regions. All of silenced clusters located in subtelomeric regions were derepressed in ΔlaeAΔcreA, hence showing that lack of CreA could remediate the repression of gene clusters in ΔlaeA background. Results show that both putative methyltransferase LaeA and transcription factor CreA are necessary for proper asexual development and controlling secondary metabolic gene cluster expression.
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Affiliation(s)
- Xiujun Zhang
- National Glycoengineering Research Center and State Key Lab of Microbial Technology, Shandong University, Jinan 250100, China; Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Jinan 250100, China.
| | - Yingying Zhu
- National Glycoengineering Research Center and State Key Lab of Microbial Technology, Shandong University, Jinan 250100, China.
| | - Longfei Bao
- National Glycoengineering Research Center and State Key Lab of Microbial Technology, Shandong University, Jinan 250100, China.
| | - Liwei Gao
- National Glycoengineering Research Center and State Key Lab of Microbial Technology, Shandong University, Jinan 250100, China.
| | - Guangshan Yao
- National Glycoengineering Research Center and State Key Lab of Microbial Technology, Shandong University, Jinan 250100, China.
| | - Yanan Li
- National Glycoengineering Research Center and State Key Lab of Microbial Technology, Shandong University, Jinan 250100, China; Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Jinan 250100, China.
| | - Zhifeng Yang
- School of Mathematics, Shandong University, Jinan 250100, China.
| | - Zhonghai Li
- National Glycoengineering Research Center and State Key Lab of Microbial Technology, Shandong University, Jinan 250100, China.
| | - Yaohua Zhong
- National Glycoengineering Research Center and State Key Lab of Microbial Technology, Shandong University, Jinan 250100, China.
| | - Fuli Li
- Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China.
| | - Heng Yin
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
| | - Yinbo Qu
- National Glycoengineering Research Center and State Key Lab of Microbial Technology, Shandong University, Jinan 250100, China.
| | - Yuqi Qin
- National Glycoengineering Research Center and State Key Lab of Microbial Technology, Shandong University, Jinan 250100, China; Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Jinan 250100, China.
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29
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Zeilinger S, Gruber S, Bansal R, Mukherjee PK. Secondary metabolism in Trichoderma – Chemistry meets genomics. FUNGAL BIOL REV 2016. [DOI: 10.1016/j.fbr.2016.05.001] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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30
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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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31
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Schumacher J, Simon A, Cohrs KC, Traeger S, Porquier A, Dalmais B, Viaud M, Tudzynski B. The VELVET Complex in the Gray Mold Fungus Botrytis cinerea: Impact of BcLAE1 on Differentiation, Secondary Metabolism, and Virulence. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2015; 28:659-74. [PMID: 25625818 DOI: 10.1094/mpmi-12-14-0411-r] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Botrytis cinerea, the gray mold fungus, is an important plant pathogen. Field populations are characterized by variability with regard to morphology, the mode of reproduction (conidiation or sclerotia formation), the spectrum of secondary metabolites (SM), and virulence. Natural variation in bcvel1 encoding the ortholog of Aspergillus nidulans VeA, a member of the VELVET complex, was previously shown to affect light-dependent differentiation, the formation of oxalic acid (OA), and virulence. To gain broader insight into the B. cinerea VELVET complex, an ortholog of A. nidulans LaeA, BcLAE1, a putative interaction partner of BcVEL1, was studied. BcVEL1 but not its truncated versions interacts with BcLAE1 and BcVEL2 (VelB ortholog). In accordance with the expected common as well as specific functions of BcVEL1 and BcLAE1, the deletions of both genes result in similar though not identical phenotypes. Both mutants lost the ability to produce OA, to colonize the host tissue, and to form sclerotia. However, mutants differ with regard to aerial hyphae and conidia formation. Genome-wide expression analyses revealed that BcVEL1 and BcLAE1 have common and distinct target genes. Some of the genes that are underexpressed in both mutants, e.g., those encoding SM-related enzymes, proteases, and carbohydrate-active enzymes, may account for their reduced virulence.
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Affiliation(s)
| | - Adeline Simon
- 2 BIOGER, INRA, Avenue Lucien Brétignières, 78850 Grignon, France
| | - Kim C Cohrs
- 1 IBBP, WWU Münster, Schlossplatz 8, 48143 Münster, Germany
| | | | - Antoine Porquier
- 2 BIOGER, INRA, Avenue Lucien Brétignières, 78850 Grignon, France
- 3 Université Paris-Sud, 91405 Orsay, France
| | | | - Muriel Viaud
- 2 BIOGER, INRA, Avenue Lucien Brétignières, 78850 Grignon, France
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Nicolás FE, Vila A, Moxon S, Cascales MD, Torres-Martínez S, Ruiz-Vázquez RM, Garre V. The RNAi machinery controls distinct responses to environmental signals in the basal fungus Mucor circinelloides. BMC Genomics 2015; 16:237. [PMID: 25880254 PMCID: PMC4417260 DOI: 10.1186/s12864-015-1443-2] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Accepted: 03/06/2015] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND RNA interference (RNAi) is a conserved mechanism of genome defence that can also have a role in the regulation of endogenous functions through endogenous small RNAs (esRNAs). In fungi, knowledge of the functions regulated by esRNAs has been hampered by lack of clear phenotypes in most mutants affected in the RNAi machinery. Mutants of Mucor circinelloides affected in RNAi genes show defects in physiological and developmental processes, thus making Mucor an outstanding fungal model for studying endogenous functions regulated by RNAi. Some classes of Mucor esRNAs map to exons (ex-siRNAs) and regulate expression of the genes from which they derive. To have a broad picture of genes regulated by the silencing machinery during vegetative growth, we have sequenced and compared the mRNA profiles of mutants in the main RNAi genes by using RNA-seq. In addition, we have achieved a more complete phenotypic characterization of silencing mutants. RESULTS Deletion of any main RNAi gene provoked a deep impact in mRNA accumulation at exponential and stationary growth. Genes showing increased mRNA levels, as expected for direct ex-siRNAs targets, but also genes with decreased expression were detected, suggesting that, most probably, the initial ex-siRNA targets regulate the expression of other genes, which can be up- or down-regulated. Expression of 50% of the genes was dependent on more than one RNAi gene in agreement with the existence of several classes of ex-siRNAs produced by different combinations of RNAi proteins. These combinations of proteins have also been involved in the regulation of different cellular processes. Besides genes regulated by the canonical RNAi pathway, this analysis identified processes, such as growth at low pH and sexual interaction that are regulated by a dicer-independent non-canonical RNAi pathway. CONCLUSION This work shows that the RNAi pathways play a relevant role in the regulation of a significant number of endogenous genes in M. circinelloides during exponential and stationary growth phases and opens up an important avenue for in-depth study of genes involved in the regulation of physiological and developmental processes in this fungal model.
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Affiliation(s)
- Francisco E Nicolás
- Department of Genetics and Microbiology, Faculty of Biology, University of Murcia, 30100, Murcia, Spain.
| | - Ana Vila
- Department of Genetics and Microbiology, Faculty of Biology, University of Murcia, 30100, Murcia, Spain.
| | - Simon Moxon
- The Genome Analysis Centre, Norwich, NR4 7UH, UK.
| | - María D Cascales
- Department of Genetics and Microbiology, Faculty of Biology, University of Murcia, 30100, Murcia, Spain.
| | - Santiago Torres-Martínez
- Department of Genetics and Microbiology, Faculty of Biology, University of Murcia, 30100, Murcia, Spain.
| | - Rosa M Ruiz-Vázquez
- Department of Genetics and Microbiology, Faculty of Biology, University of Murcia, 30100, Murcia, Spain.
| | - Victoriano Garre
- Department of Genetics and Microbiology, Faculty of Biology, University of Murcia, 30100, Murcia, Spain.
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Ruiz-Vázquez RM, Nicolás FE, Torres-Martínez S, Garre V. Distinct RNAi Pathways in the Regulation of Physiology and Development in the Fungus Mucor circinelloides. ADVANCES IN GENETICS 2015; 91:55-102. [DOI: 10.1016/bs.adgen.2015.07.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Daguerre Y, Siegel K, Edel-Hermann V, Steinberg C. Fungal proteins and genes associated with biocontrol mechanisms of soil-borne pathogens: a review. FUNGAL BIOL REV 2014. [DOI: 10.1016/j.fbr.2014.11.001] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Bok JW, Wiemann P, Garvey GS, Lim FY, Haas B, Wortman J, Keller NP. Illumina identification of RsrA, a conserved C2H2 transcription factor coordinating the NapA mediated oxidative stress signaling pathway in Aspergillus. BMC Genomics 2014; 15:1011. [PMID: 25416206 PMCID: PMC4252986 DOI: 10.1186/1471-2164-15-1011] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 11/12/2014] [Indexed: 12/30/2022] Open
Abstract
Background Chemical mutagenesis screens are useful to identify mutants involved in biological processes of interest. Identifying the mutation from such screens, however, often fails when using methodologies involving transformation of the mutant to wild type phenotype with DNA libraries. Results Here we analyzed Illumina sequence of a chemically derived mutant of Aspergillus nidulans and identified a gene encoding a C2H2 transcription factor termed RsrA for regulator of stress response. RsrA is conserved in filamentous fungal genomes, and upon deleting the gene in three Aspergillus species (A. nidulans, A. flavus and A. fumigatus), we found two conserved phenotypes: enhanced resistance to oxidative stress and reduction in sporulation processes. For all species, rsrA deletion mutants were more resistant to hydrogen peroxide treatment. In depth examination of this latter characteristic in A. nidulans showed that upon exposure to hydrogen peroxide, RsrA loss resulted in global up-regulation of several components of the oxidative stress metabolome including the expression of napA and atfA, the two bZIP transcription factors mediating resistance to reactive oxygen species (ROS) as well as NapA targets in thioredoxin and glutathione systems. Coupling transcriptional data with examination of ΔrsrAΔatfA and ΔrsrAΔnapA double mutants indicate that RsrA primarily operates through NapA-mediated stress response pathways. A model of RsrA regulation of ROS response in Aspergillus is presented. Conclusion RsrA, found in a highly syntenic region in Aspergillus genomes, coordinates a NapA mediated oxidative response in Aspergillus fungi. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-1011) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | | | | | | | | | - Nancy P Keller
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, USA.
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