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Zhu L, Tang L, Tian X, Bai Y, Huang L. Two Polyketide Synthase Genes, VpPKS10 and VpPKS33, Regulated by VpLaeA Are Essential to the Virulence of Valsa pyri. PHYTOPATHOLOGY 2024:PHYTO12230498R. [PMID: 38916927 DOI: 10.1094/phyto-12-23-0498-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/26/2024]
Abstract
Valsa pyri, the causal agent of pear canker disease, typically induces cankers on the bark of infected trees and even leads to tree mortality. Secondary metabolites produced by pathogenic fungi play a crucial role in the pathogenic process. In this study, secondary metabolic regulator VpLaeA was identified in V. pyri. VpLaeA was found to strongly affect the pathogenicity, fruiting body formation, and toxicity of secondary metabolites of V. pyri. Additionally, VpLaeA was found to be required for the response of V. pyri to some abiotic stresses. Transcriptome data analysis revealed that many of differentially expressed genes were involved in the secondary metabolite biosynthesis. Among them, about one third of secondary metabolite biosynthesis core genes were regulated by VpLaeA at different periods. Seven differentially expressed secondary metabolite biosynthesis core genes (VpPKS9, VpPKS10, VpPKS33, VpNRPS6, VpNRPS7, VpNRPS16, and VpNRPS17) were selected for knockout. Two modular polyketide synthase genes (VpPKS10 and VpPKS33) that were closely related to the virulence of V. pyri from the above seven genes were identified. Notably, VpPKS10 and VpPKS33 also affected the production of fruiting body of V. pyri but did not participate in the resistance of V. pyri to abiotic stresses. Overall, this study demonstrates the multifaceted biological functions of VpLaeA in V. pyri and identifies two toxicity-associated polyketide synthase genes in Valsa species fungi for the first time.
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Affiliation(s)
- Liangliang Zhu
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, College of Plant Protection, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Lin Tang
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, College of Plant Protection, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Xiangrong Tian
- College of Forestry, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Yayuan Bai
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, College of Plant Protection, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Lili Huang
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, College of Plant Protection, Northwest A&F University, Yangling 712100, Shaanxi, China
- Tarim University, Alar 843300, Xingjiang Uyghur Autonomous Region, China
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Guan J, Wang W, Zhang K, Shi X, Yang Q, Song J. Role of AplaeA in the regulation of spore production and poly(malic acid) synthesis in Aureobasidium pullulans. Int J Biol Macromol 2024; 279:135153. [PMID: 39214223 DOI: 10.1016/j.ijbiomac.2024.135153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2024] [Revised: 08/09/2024] [Accepted: 08/27/2024] [Indexed: 09/04/2024]
Abstract
Poly(malic acid) (PMLA) as one of the important metabolites in Aureobasidium pullulans has great application in a variety of fields. LaeA, a global regulator capable of controlling fungal secondary metabolites, has been identified in A. pullulans. The involvement of LaeA in the biosynthesis of PMLA through direct or indirect means and its role in A. pullulans is currently unknown. Here we extracted and characterized the AplaeA gene from A. pullulans HIT-LCY3T and resolved it by bioinformatics. The function of AplaeA was subsequently characterized by Rnai-LaeA and OEX-LaeA mutants. Based on phenotypic observations of the mutant strains, it was found that the gene had a large effect on the morphology and melanin production aspects of the strain, and that overexpression of the AplaeA gene resulted in a substantial increase in spore numbers. RT-qPCR combined with protein interactions results analyzed that ApLaeA positively regulates PMLA biosynthesis by controlling the expression of core genes of PMLA biosynthesis gene cluster and other related regulatory factors. Finally, OEX-LaeA was used as the starting strain to obtain the optimal fermentation conditions. These findings illustrate the regulatory mechanism of a hypothesized global regulator, LaeA, in A. pullulans HIT-LCY3T, suggesting its potential application in industrial-scale PMLA biosynthesis.
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Affiliation(s)
- Jiaqi Guan
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150006, China
| | - Wan Wang
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150006, China
| | - Kai Zhang
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150006, China
| | - Xinyue Shi
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150006, China
| | - Qian Yang
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150006, China; State Key Laboratory of Urban Water Resources and Environment, Harbin Institute of Technology, Harbin 150090, China.
| | - Jinzhu Song
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150006, China.
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Zhang X, Yang Y, Wang L, Qin Y. Histone H2B lysine 122 and lysine 130, as the putative targets of Penicillium oxalicum LaeA, play important roles in asexual development, expression of secondary metabolite gene clusters, and extracellular glycoside hydrolase synthesis. World J Microbiol Biotechnol 2024; 40:179. [PMID: 38668807 DOI: 10.1007/s11274-024-03978-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 04/03/2024] [Indexed: 05/01/2024]
Abstract
Core histones in the nucleosome are subject to a wide variety of posttranslational modifications (PTMs), such as methylation, phosphorylation, ubiquitylation, and acetylation, all of which are crucial in shaping the structure of the chromatin and the expression of the target genes. A putative histone methyltransferase LaeA/Lae1, which is conserved in numerous filamentous fungi, functions as a global regulator of fungal growth, virulence, secondary metabolite formation, and the production of extracellular glycoside hydrolases (GHs). LaeA's direct histone targets, however, were not yet recognized. Previous research has shown that LaeA interacts with core histone H2B. Using S-adenosyl-L-methionine (SAM) as a methyl group donor and recombinant human histone H2B as the substrate, it was found that Penicillium oxalicum LaeA can transfer the methyl groups to the C-terminal lysine (K) 108 and K116 residues in vitro. The H2BK108 and H2BK116 sites on recombinant histone correspond to P. oxalicum H2BK122 and H2BK130, respectively. H2BK122A and H2BK130A, two mutants with histone H2B K122 or K130 mutation to alanine (A), were constructed in P. oxalicum. The mutants H2BK122A and H2BK130A demonstrated altered asexual development and decreased extracellular GH production, consistent with the findings of the laeA gene deletion strain (ΔlaeA). The transcriptome data showed that when compared to wild-type (WT) of P. oxalicum, 38 of the 47 differentially expressed (fold change ≥ 2, FDR ≤ 0.05) genes that encode extracellular GHs showed the same expression pattern in the three mutants ΔlaeA, H2BK122A, and H2BK130A. The four secondary metabolic gene clusters that considerably decreased expression in ΔlaeA also significantly decreased in H2BK122A or H2BK130A. The chromatin of promotor regions of the key cellulolytic genes cel7A/cbh1 and cel7B/eg1 compacted in the ΔlaeA, H2BK122A, and H2BK130A mutants, according to the results of chromatin accessibility real-time PCR (CHART-PCR). The chromatin accessibility index dropped. The histone binding pocket of the LaeA-methyltransf_23 domain is compatible with particular histone H2B peptides, providing appropriate electrostatic and steric compatibility to stabilize these peptides, according to molecular docking. The findings of the study demonstrate that H2BK122 and H2BK130, which are histone targets of P. oxalicum LaeA in vitro, are crucial for fungal conidiation, the expression of gene clusters encoding secondary metabolites, and the production of extracellular GHs.
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Affiliation(s)
- Xiujun Zhang
- National Glycoengineering Research Center, Shandong University, Qingdao, China
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China
- School of Biological Science and Technology, University of Jinan, Jinan, China
| | - Yuhong Yang
- School of Biological Science and Technology, University of Jinan, Jinan, China
| | - Lushan Wang
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China
| | - Yuqi Qin
- National Glycoengineering Research Center, Shandong University, Qingdao, China.
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China.
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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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Marcano Y, Montanares M, Gil-Durán C, González K, Levicán G, Vaca I, Chávez R. Pr laeA Affects the Production of Roquefortine C, Mycophenolic Acid, and Andrastin A in Penicillium roqueforti, but It Has Little Impact on Asexual Development. J Fungi (Basel) 2023; 9:954. [PMID: 37888210 PMCID: PMC10607316 DOI: 10.3390/jof9100954] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 09/14/2023] [Accepted: 09/20/2023] [Indexed: 10/28/2023] Open
Abstract
The regulation of fungal specialized metabolism is a complex process involving various regulators. Among these regulators, LaeA, a methyltransferase protein originally discovered in Aspergillus spp., plays a crucial role. Although the role of LaeA in specialized metabolism has been studied in different fungi, its function in Penicillium roqueforti remains unknown. In this study, we employed CRISPR-Cas9 technology to disrupt the laeA gene in P. roqueforti (PrlaeA) aiming to investigate its impact on the production of the specialized metabolites roquefortine C, mycophenolic acid, and andrastin A, as well as on asexual development, because they are processes that occur in the same temporal stages within the physiology of the fungus. Our results demonstrate a substantial reduction in the production of the three metabolites upon disruption of PrlaeA, suggesting a positive regulatory role of LaeA in their biosynthesis. These findings were further supported by qRT-PCR analysis, which revealed significant downregulation in the expression of genes associated with the biosynthetic gene clusters (BGCs) responsible for producing roquefortine C, mycophenolic acid, and andrastin A in the ΔPrlaeA strains compared with the wild-type P. roqueforti. Regarding asexual development, the disruption of PrlaeA led to a slight decrease in colony growth rate, while conidiation and conidial germination remained unaffected. Taken together, our results suggest that LaeA positively regulates the expression of the analyzed BGCs and the production of their corresponding metabolites in P. roqueforti, but it has little impact on asexual development.
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Affiliation(s)
- Yudethzi Marcano
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile (USACH), Santiago 9170022, Chile; (Y.M.); (C.G.-D.); (K.G.); (G.L.)
| | - Mariana Montanares
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Santiago 7800003, Chile;
| | - Carlos Gil-Durán
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile (USACH), Santiago 9170022, Chile; (Y.M.); (C.G.-D.); (K.G.); (G.L.)
| | - Kathia González
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile (USACH), Santiago 9170022, Chile; (Y.M.); (C.G.-D.); (K.G.); (G.L.)
| | - Gloria Levicán
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile (USACH), Santiago 9170022, Chile; (Y.M.); (C.G.-D.); (K.G.); (G.L.)
| | - Inmaculada Vaca
- Departamento de Química, Facultad de Ciencias, Universidad de Chile, Santiago 7800003, Chile;
| | - Renato Chávez
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile (USACH), Santiago 9170022, Chile; (Y.M.); (C.G.-D.); (K.G.); (G.L.)
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Yu W, Pei R, Zhang Y, Tu Y, He B. Light regulation of secondary metabolism in fungi. J Biol Eng 2023; 17:57. [PMID: 37653453 PMCID: PMC10472637 DOI: 10.1186/s13036-023-00374-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 08/22/2023] [Indexed: 09/02/2023] Open
Abstract
Fungi have evolved unique metabolic regulation mechanisms for adapting to the changing environments. One of the key features of fungal adaptation is the production of secondary metabolites (SMs), which are essential for survival and beneficial to the organism. Many of these SMs are produced in response to the environmental cues, such as light. In all fungal species studied, the Velvet complex transcription factor VeA is a central player of the light regulatory network. In addition to growth and development, the intensity and wavelength of light affects the formation of a broad range of secondary metabolites. Recent studies, mainly on species of the genus Aspergillus, revealed that the dimer of VeA-VelB and LaeA does not only regulate gene expression in response to light, but can also be involved in regulating production of SMs. Furthermore, the complexes have a wide regulatory effect on different types of secondary metabolites. In this review, we discussed the role of light in the regulation of fungal secondary metabolism. In addition, we reviewed the photoreceptors, transcription factors, and signaling pathways that are involved in light-dependent regulation of secondary metabolism. The effects of transcription factors on the production of secondary metabolites, as well as the potential applications of light regulation for the production of pharmaceuticals and other products were discussed. Finally, we provided an overview of the current research in this field and suggested potential areas for future research.
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Affiliation(s)
- Wenbin Yu
- Jiangxi Key Laboratory of Bioprocess Engineering, College of Life Sciences, Jiangxi Science & Technology Normal University, Nanchang, 330013, Jiangxi, China
| | - Rongqiang Pei
- Jiangxi Key Laboratory of Bioprocess Engineering, College of Life Sciences, Jiangxi Science & Technology Normal University, Nanchang, 330013, Jiangxi, China
| | - Yufei Zhang
- Jiangxi Key Laboratory of Bioprocess Engineering, College of Life Sciences, Jiangxi Science & Technology Normal University, Nanchang, 330013, Jiangxi, China
| | - Yayi Tu
- Jiangxi Key Laboratory of Bioprocess Engineering, College of Life Sciences, Jiangxi Science & Technology Normal University, Nanchang, 330013, Jiangxi, China.
| | - Bin He
- Jiangxi Key Laboratory of Bioprocess Engineering, College of Life Sciences, Jiangxi Science & Technology Normal University, Nanchang, 330013, Jiangxi, China.
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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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Nowrousian M. The Role of Chromatin and Transcriptional Control in the Formation of Sexual Fruiting Bodies in Fungi. Microbiol Mol Biol Rev 2022; 86:e0010422. [PMID: 36409109 PMCID: PMC9769939 DOI: 10.1128/mmbr.00104-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Fungal fruiting bodies are complex, three-dimensional structures that arise from a less complex vegetative mycelium. Their formation requires the coordinated action of many genes and their gene products, and fruiting body formation is accompanied by major changes in the transcriptome. In recent years, numerous transcription factor genes as well as chromatin modifier genes that play a role in fruiting body morphogenesis were identified, and through research on several model organisms, the underlying regulatory networks that integrate chromatin structure, gene expression, and cell differentiation are becoming clearer. This review gives a summary of the current state of research on the role of transcriptional control and chromatin structure in fruiting body development. In the first part, insights from transcriptomics analyses are described, with a focus on comparative transcriptomics. In the second part, examples of more detailed functional characterizations of the role of chromatin modifiers and/or transcription factors in several model organisms (Neurospora crassa, Aspergillus nidulans, Sordaria macrospora, Coprinopsis cinerea, and Schizophyllum commune) that have led to a better understanding of regulatory networks at the level of chromatin structure and transcription are discussed.
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Affiliation(s)
- Minou Nowrousian
- Department of Molecular and Cellular Botany, Ruhr University Bochum, Bochum, Germany
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9
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Huber EM. Epipolythiodioxopiperazine-Based Natural Products: Building Blocks, Biosynthesis and Biological Activities. Chembiochem 2022; 23:e202200341. [PMID: 35997236 PMCID: PMC10086836 DOI: 10.1002/cbic.202200341] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 08/19/2022] [Indexed: 01/25/2023]
Abstract
Epipolythiodioxopiperazines (ETPs) are fungal secondary metabolites that share a 2,5-diketopiperazine scaffold built from two amino acids and bridged by a sulfide moiety. Modifications of the core and the amino acid side chains, for example by methylations, acetylations, hydroxylations, prenylations, halogenations, cyclizations, and truncations create the structural diversity of ETPs and contribute to their biological activity. However, the key feature responsible for the bioactivities of ETPs is their sulfide moiety. Over the last years, combinations of genome mining, reverse genetics, metabolomics, biochemistry, and structural biology deciphered principles of ETP production. Sulfurization via glutathione and uncovering of the thiols followed by either oxidation or methylation crystallized as fundamental steps that impact expression of the biosynthesis cluster, toxicity and secretion of the metabolite as well as self-tolerance of the producer. This article showcases structure and activity of prototype ETPs such as gliotoxin and discusses the current knowledge on the biosynthesis routes of these exceptional natural products.
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Affiliation(s)
- Eva M Huber
- Chair of Biochemistry, Center for Protein Assemblies, Technical University of Munich, Ernst-Otto-Fischer-Str. 8, 85748, Garching, Germany
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10
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Mahata PK, Dass RS, Gunti L, Thorat PA. First report on the metabolic characterization of Sterigmatocystin production by select Aspergillus species from the Nidulantes section in Foeniculum vulgare. Front Microbiol 2022; 13:958424. [PMID: 36090109 PMCID: PMC9459157 DOI: 10.3389/fmicb.2022.958424] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 08/03/2022] [Indexed: 12/16/2022] Open
Abstract
Spices are typically grown in climates that support the growth of toxigenic fungi and the production of mycotoxins. The Aspergilli described in this study, as well as the sterigmatocystin (STC) detected, are causes for concern due to their potential to induce food poisoning. One of the most well-known producers of the carcinogenic STC is Aspergillus nidulans. This research explores the occurrence of STC-producing fungi in Foeniculum vulgare, a spice that is marketed in India and other parts of the world. This innovative study details the mycotoxigenic potential of five Aspergilli belonging to Section Nidulantes, namely Aspergillus latus (02 isolates), Emericella quadrilineata (02 isolates), and Aspergillus nidulans (01 isolate), with respect to STC contamination. These five isolates of Aspergilli were screened to produce STC on yeast extract sucrose (YES) medium in a controlled environment with regard to light, temperature, pH, and humidity, among other variables. The expression patterns of regulatory genes, namely, aflR, laeA, pacC, fluG, flbA, pksA, and mtfA were studied on the Czapek–Dox agar (CDA) medium. STC biosynthesis by the test isolates was done in potato dextrose broth (PDB) under optimum conditions, followed by the extraction and purification of the broth using ethyl acetate. High-performance liquid chromatography (HPLC) with an ultraviolet (UV) detector was utilized to detect compounds in eluted samples. F. vulgare contains Aspergilli that have been shown to have mycotoxigenic potential, which can accumulate in the spice during its active growth and thereby cause the elaboration of mycotoxins.
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Wei Z, Shu D, Sun Q, Chen DB, Li ZM, Luo D, Yang J, Tan H. The BcLAE1 is involved in the regulation of ABA biosynthesis in Botrytis cinerea TB-31. Front Microbiol 2022; 13:969499. [PMID: 35992717 PMCID: PMC9386520 DOI: 10.3389/fmicb.2022.969499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 07/07/2022] [Indexed: 11/13/2022] Open
Abstract
Abscisic acid (ABA), as a classic plant hormone, is a key factor in balancing the metabolism of endogenous plant hormones, and plays an important role in regulating the activation of mammalian innate immune cells and glucose homeostasis. Currently, Botrytis cinerea has been used for fermentation to produce ABA. However, the mechanism of the regulation of ABA biosynthesis in B. cinerea is still not fully understood. The putative methyltransferase LaeA/LAE1 is a global regulator involved in the biosynthesis of a variety of secondary metabolites in filamentous fungi. In this study, we demonstrated that BcLAE1 plays an important role in the regulation of ABA biosynthesis in B. cinerea TB-31 by knockout experiment. The deletion of Bclae1 caused a 95% reduction in ABA yields, accompanied by a decrease of the transcriptional level of the ABA synthesis gene cluster Bcaba1-4. Further RNA-seq analysis indicated that deletion of Bclae1 also affected the expression level of key enzymes of BOA and BOT in secondary metabolism, and accompanied by clustering regulatory features. Meanwhile, we found that BcLAE1 is involved in epigenetic regulation as a methyltransferase, with enhanced H3K9me3 modification and attenuated H3K4me2 modification in ΔBclae1 mutant, and this may be a strategy for BcLAE1 to regulate ABA synthesis.
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Affiliation(s)
- Zhao Wei
- CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
- Key Laboratory of Bio-Resources and Eco-Environment Ministry of the Education, College of Life Sciences, Sichuan University, Chengdu, China
- University of the Chinese Academy of Sciences, Beijing, China
| | - Dan Shu
- CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
- *Correspondence: Dan Shu,
| | - Qun Sun
- Key Laboratory of Bio-Resources and Eco-Environment Ministry of the Education, College of Life Sciences, Sichuan University, Chengdu, China
| | - Dong-bo Chen
- CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
- University of the Chinese Academy of Sciences, Beijing, China
| | - Zhe-min Li
- CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
| | - Di Luo
- CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
| | - Jie Yang
- CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
| | - Hong Tan
- CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
- Hong Tan,
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12
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LaeA regulates morphological development and ochratoxin A biosynthesis in Aspergillus niger. Mycotoxin Res 2022; 38:221-229. [PMID: 35879501 DOI: 10.1007/s12550-022-00463-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 07/01/2022] [Accepted: 07/19/2022] [Indexed: 10/16/2022]
Abstract
The global regulator LaeA and its orthologs govern the morphogenetic development and secondary metabolism of several filamentous ascomycetes. In Aspergillus niger, it has been shown that an LaeA ortholog (AnLaeA) regulates the production of citric acid and secondary metabolites. In this work, we constructed AnlaeA disruption and overexpression strains to investigate the roles of AnLaeA in morphological development and ochratoxin A (OTA) biosynthesis in A. niger. Phenotypic observation, chemical analysis, and gene expression analysis indicated that AnLaeA acts as a negative regulator of conidial morphogenesis and positively regulates gene expression of the OTA cluster in A. niger grown in CYA medium. However, it was observed that the upregulation of gene expression of the OTA cluster does not necessarily increase OTA production. Our results contribute to a better understanding of the AnlaeA regulatory mechanism and suggest the AnlaeA gene as a potential target for developing control strategies for A. niger infection and OTA biosynthesis.
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13
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Mersaoui SY, Guilbert C, Chou H, Douillet C, Bohle DS, Stýblo M, Richard S, Mann KK. Arsenic 3 methyltransferase (AS3MT) automethylates on cysteine residues in vitro. Arch Toxicol 2022; 96:1371-1386. [PMID: 35244730 PMCID: PMC9013690 DOI: 10.1007/s00204-022-03248-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 02/02/2022] [Indexed: 11/25/2022]
Abstract
Arsenic toxicity is a global concern to human health causing increased incidences of cancer, bronchopulmonary, and cardiovascular diseases. In human and mouse, inorganic arsenic (iAs) is metabolized in a series of methylation steps catalyzed by arsenic (3) methyltransferase (AS3MT), forming methylated arsenite (MAsIII), dimethylarsenite (DMAIII) and the volatile trimethylarsine (TMA). The methylation of arsenic is coordinated by four conserved cysteines proposed to participate in catalysis, namely C33, C62, C157, and C207 in mouse AS3MT. The current model consists of AS3MT methylating iAs in the presence of the cofactor S-adenosyl-L-methionine (SAM), and the formation of intramolecular disulfide bonds following the reduction of MAsV to MAsIII. In the presence of endogenous reductants, these disulfide bonds are reduced, the enzyme re-generates, and the second round of methylation ensues. Using in vitro methylation assays, we find that AS3MT undergoes an initial automethylation step in the absence of iAs. This automethylation is enhanced by glutathione (GSH) and dithiothreitol (DTT), suggesting that reduced cysteines accept methyl groups from SAM to form S-methylcysteines. Following the addition of iAs, automethylation of AS3MT is decreased. Furthermore, using a Flag-AS3MT immunoprecipitation coupled to MS/MS, we identify both C33 and C62 as acceptors of the methyl group in vivo. Site-directed mutagenesis (C to A) revealed that three of the previously described cysteines were required for AS3MT automethylation. In vitro experiments show that automethylated AS3MT can methylate iAs in the presence of SAM. Thus, we propose that automethylated may represent an active conformation of AS3MT.
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Affiliation(s)
- Sofiane Y Mersaoui
- Segal Cancer Center, Lady Davis Institute for Medical Research and Departments of Oncology and Medicine, McGill University, Montréal, Québec, H3T 1E2, Canada
| | - Cynthia Guilbert
- Segal Cancer Center, Lady Davis Institute for Medical Research and Departments of Oncology and Medicine, McGill University, Montréal, Québec, H3T 1E2, Canada
| | - Hsiang Chou
- Segal Cancer Center, Lady Davis Institute for Medical Research and Departments of Oncology and Medicine, McGill University, Montréal, Québec, H3T 1E2, Canada
| | - Christelle Douillet
- Department of Nutrition, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, CB# 7461, Chapel Hill, NC, 27599, USA
| | - D Scott Bohle
- Department of Chemistry, McGill University, Otto Maass 233A, Montréal, Québec, H3A 0B8, Canada
| | - Miroslav Stýblo
- Department of Nutrition, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, CB# 7461, Chapel Hill, NC, 27599, USA
| | - Stéphane Richard
- Segal Cancer Center, Lady Davis Institute for Medical Research and Departments of Oncology and Medicine, McGill University, Montréal, Québec, H3T 1E2, Canada.
| | - Koren K Mann
- Segal Cancer Center, Lady Davis Institute for Medical Research and Departments of Oncology and Medicine, McGill University, Montréal, Québec, H3T 1E2, Canada.
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14
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Zhang X, Hu Y, Liu G, Liu M, Li Z, Zhao J, Song X, Zhong Y, Qu Y, Wang L, Qin Y. The complex Tup1-Cyc8 bridges transcription factor ClrB and putative histone methyltransferase LaeA to activate the expression of cellulolytic genes. Mol Microbiol 2022; 117:1002-1022. [PMID: 35072962 DOI: 10.1111/mmi.14885] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 01/18/2022] [Accepted: 01/20/2022] [Indexed: 11/28/2022]
Abstract
The degradation of lignocellulosic biomass by cellulolytic enzymes is involved in the global carbon cycle. The hydrolysis of lignocellulosic biomass into fermentable sugars is potential as excellent industrial resource to produce a variety of chemical products. The production of cellulolytic enzymes is regulated mainly at the transcriptional level in filamentous fungi. Transcription factor ClrB and the putative histone methyltransferase LaeA, are both necessary for the expression of cellulolytic genes. However, the mechanism by which transcription factors and methyltransferase coordinately regulate cellulolytic genes is still unknown. Here, we reveal a transcriptional regulatory mechanism involving Penicillium oxalicum transcription factor ClrB (PoClrB), complex Tup1-Cyc8, and putative histone methyltransferase LaeA (PoLaeA). As the transcription factor, PoClrB binds the targeted promoters of cellulolytic genes, recruits PoTup1-Cyc8 complex via direct interaction with PoTup1. PoTup1 interacts with PoCyc8 to form the coactivator complex PoTup1-Cyc8. Then, PoTup1 recruits putative histone methyltransferase PoLaeA to modify the chromatin structure of the upstream region of cellulolytic genes, thereby facilitating the binding of transcription machinery to activating the corresponding cellulolytic gene expression. Our results contribute to a better understanding of complex transcriptional regulation mechanisms of cellulolytic genes and will be valuable for lignocellulosic biorefining.
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Affiliation(s)
- Xiujun Zhang
- National Glycoengineering Research Center, Shandong University, Qingdao, China.,State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China.,School of Biological Science and Technology, University of Jinan, Jinan, China
| | - Yueyan Hu
- National Glycoengineering Research Center, Shandong University, Qingdao, China.,State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China
| | - Guodong Liu
- National Glycoengineering Research Center, Shandong University, Qingdao, China.,State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China
| | - Meng Liu
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China
| | - Zhonghai Li
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China.,State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology, Shandong Academy of Sciences, Jinan, China
| | - Jian Zhao
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China
| | - Xin Song
- National Glycoengineering Research Center, Shandong University, Qingdao, China.,State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China
| | - Yaohua Zhong
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China
| | - Yinbo Qu
- National Glycoengineering Research Center, Shandong University, Qingdao, China.,State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China
| | - Lushan Wang
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China
| | - Yuqi Qin
- National Glycoengineering Research Center, Shandong University, Qingdao, China.,State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, Qingdao, China
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15
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Kemppainen M, Pardo A. Nucleus-directed fluorescent reporter system for promoter studies in the ectomycorrhizal fungus Laccaria bicolor. J Microbiol Methods 2021; 190:106341. [PMID: 34610385 DOI: 10.1016/j.mimet.2021.106341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 09/30/2021] [Accepted: 09/30/2021] [Indexed: 11/19/2022]
Abstract
Currently ectomycorrhizal research suffers from a lack of molecular tools specifically adapted to study gene expression in fungal symbionts. Considering that, we designed pReNuK, a cloning vector for transcriptional promoter studies in the ectomycorrhizal basidiomycete Laccaria bicolor. The pReNuK vector offers the use of a nuclear localizing and chromatin incorporating histone H2B-mCherry fluorescent reporter protein and it is specifically optimized for efficient transgene expression in Laccaria. Moreover, pReNuK is designed to work in concert with Agrobacterium-mediated transformation under hygromycin B resistance selection. The functionality of the pReNuK reporter system was tested with the constitutive Laccaria glyceraldehyde 3-phosphate dehydrogenase gene promoter and further validated with the nitrogen source regulated nitrate reductase gene promoter. The expression of the nucleus-directed H2B-mCherry reporter is highly stable in time. Moreover, the transformation of Laccaria with pReNuK and the expression of the reporter do not have negative effects on the growth of the fungus. The pReNuK offers a novel tool for studying in vivo gene expression regulation in Laccaria, the leading fungal model for ectomycorrhizal research.
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Affiliation(s)
- Minna Kemppainen
- Laboratory of Molecular Mycology, Institute of Basic and Applied Microbiology, Department of Science and Technology, National University of Quilmes and CONICET, Bernal, Province of Buenos Aires, Argentina.
| | - Alejandro Pardo
- Laboratory of Molecular Mycology, Institute of Basic and Applied Microbiology, Department of Science and Technology, National University of Quilmes and CONICET, Bernal, Province of Buenos Aires, Argentina
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16
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Huang L, Li X, Dong L, Wang B, Pan L. Profiling of chromatin accessibility identifies transcription factor binding sites across the genome of Aspergillus species. BMC Biol 2021; 19:189. [PMID: 34488759 PMCID: PMC8419926 DOI: 10.1186/s12915-021-01114-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Accepted: 08/02/2021] [Indexed: 12/30/2022] Open
Abstract
Background The identification of open chromatin regions and transcription factor binding sites (TFBs) is an important step in understanding the regulation of gene expression in diverse species. ATAC-seq is a technique used for such purpose by providing high-resolution measurements of chromatin accessibility revealed through integration of Tn5 transposase. However, the existence of cell walls in filamentous fungi and associated difficulty in purifying nuclei have precluded the routine application of this technique, leading to a lack of experimentally determined and computationally inferred data on the identity of genome-wide cis-regulatory elements (CREs) and TFBs. In this study, we constructed an ATAC-seq platform suitable for filamentous fungi and generated ATAC-seq libraries of Aspergillus niger and Aspergillus oryzae grown under a variety of conditions. Results We applied the ATAC-seq assay for filamentous fungi to delineate the syntenic orthologue and differentially changed chromatin accessibility regions among different Aspergillus species, during different culture conditions, and among specific TF-deleted strains. The syntenic orthologues of accessible regions were responsible for the conservative functions across Aspergillus species, while regions differentially changed between culture conditions and TFs mutants drove differential gene expression programs. Importantly, we suggest criteria to determine TFBs through the analysis of unbalanced cleavage of distinct TF-bound DNA strands by Tn5 transposase. Based on this criterion, we constructed data libraries of the in vivo genomic footprint of A. niger under distinct conditions, and generated a database of novel transcription factor binding motifs through comparison of footprints in TF-deleted strains. Furthermore, we validated the novel TFBs in vivo through an artificial synthetic minimal promoter system. Conclusions We characterized the chromatin accessibility regions of filamentous fungi species, and identified a complete TFBs map by ATAC-seq, which provides valuable data for future analyses of transcriptional regulation in filamentous fungi. Supplementary Information The online version contains supplementary material available at 10.1186/s12915-021-01114-0.
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Affiliation(s)
- Lianggang Huang
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou Higher Education Mega Center, Guangzhou, 510006, China
| | - Xuejie Li
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou Higher Education Mega Center, Guangzhou, 510006, China
| | - Liangbo Dong
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou Higher Education Mega Center, Guangzhou, 510006, China
| | - Bin Wang
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou Higher Education Mega Center, Guangzhou, 510006, China. .,Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou Higher Education Mega Center, Guangzhou, 510006, China.
| | - Li Pan
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou Higher Education Mega Center, Guangzhou, 510006, China. .,Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou Higher Education Mega Center, Guangzhou, 510006, China.
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17
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Khan I, Xie WL, Yu YC, Sheng H, Xu Y, Wang JQ, Debnath SC, Xu JZ, Zheng DQ, Ding WJ, Wang PM. Heteroexpression of Aspergillus nidulans laeA in Marine-Derived Fungi Triggers Upregulation of Secondary Metabolite Biosynthetic Genes. Mar Drugs 2020; 18:md18120652. [PMID: 33352941 PMCID: PMC7766385 DOI: 10.3390/md18120652] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 12/04/2020] [Accepted: 12/15/2020] [Indexed: 11/26/2022] Open
Abstract
Fungi are a prospective resource of bioactive compounds, but conventional methods of drug discovery are not effective enough to fully explore their metabolic potential. This study aimed to develop an easily attainable method to elicit the metabolic potential of fungi using Aspergillus nidulans laeA as a transcription regulation tool. In this study, functional analysis of Aspergillus nidulans laeA (AnLaeA) and Aspergillus sp. Z5 laeA (Az5LaeA) was done in the fungus Aspergillus sp. Z5. Heterologous AnLaeA-and native Az5LaeA-overexpression exhibited similar phenotypic effects and caused an increase in production of a bioactive compound diorcinol in Aspergillus sp. Z5, which proved the conserved function of this global regulator. In particular, heteroexpression of AnLaeA showed a significant impact on the expression of velvet complex genes, diorcinol synthesis-related genes, and different transcription factors (TFs). Moreover, heteroexpression of AnLaeA influenced the whole genome gene expression of Aspergillus sp. Z5 and triggered the upregulation of many genes. Overall, these findings suggest that heteroexpression of AnLaeA in fungi serves as a simple and easy method to explore their metabolic potential. In relation to this, AnLaeA was overexpressed in the fungus Penicillium sp. LC1-4, which resulted in increased production of quinolactacin A.
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18
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Zhang X, Li M, Zhu Y, Yang L, Li Y, Qu J, Wang L, Zhao J, Qu Y, Qin Y. Penicillium oxalicum putative methyltransferase Mtr23B has similarities and differences with LaeA in regulating conidium development and glycoside hydrolase gene expression. Fungal Genet Biol 2020; 143:103445. [PMID: 32822857 DOI: 10.1016/j.fgb.2020.103445] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 08/07/2020] [Accepted: 08/12/2020] [Indexed: 11/18/2022]
Abstract
Putative methyltranferase LaeA and LaeA-like proteins, which are conserved in many filamentous fungi, regulate the sporogenesis and biosynthesis of secondary metabolites. In this study, we reported the biological function of a LaeA-like methyltransferase, Penicillium oxalicum Mtr23B, which contains a methyltransf_23 domain and an S-adenosylmethionine binding domain, in controlling spore pigment formation and in the expression of secondary metabolic gene cluster and glycoside hydrolase genes. Additionally, we compared Mtr23B and LaeA, and determined their similarities and differences in terms of their roles in regulating the above biological processes. mtr23B had the highest transcriptional level among the 12 members of the methyltransf_23 family in P. oxalicum. The colony color of Δmtr23B (deletion of mtr23B) was lighter than that of ΔlaeA, although Δmtr23B produced ~ 19.2-fold more conidia than ΔlaeA. The transcriptional levels of abrA, abrB/yA, albA/wA, arpA, arpB, and aygA, which are involved in the dihydroxynaphtalene-melanin pathway, decreased in Δmtr23B. However, Mtr23B had a little effect on brush-like structures and conidium formation, and had a different function from LaeA. Mtr23B extensively regulated glycoside hydrolase gene expression. The absence of Mtr23B remarkably repressed prominent cellulase- and amylase-encoding genes in the whole culture period, while the effect of LaeA mainly occurred in the later phases of prolonged batch cultures. Similar to LaeA, Mtr23B was involved in the expression of 10 physically linked regions containing secondary metabolic gene clusters; the highest regulatory activities of Mtr23B and LaeA were observed in BrlA-dependent cascades. Although LaeA interacted with VeA, Mtr23B did not interact with VeA directly. We assumed that Mtr23B regulates cellulase and amylase gene transcription by interacting with the CCAAT-binding transcription factor HAP5 and chromatin remodeling complex.
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Affiliation(s)
- Xiujun Zhang
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, China; National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao 266237, China.
| | - Mengxue Li
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, China; National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao 266237, China
| | - Yingying Zhu
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, China
| | - Ling Yang
- Vocational Education College, Dezhou University, Dezhou 253023, China
| | - Yanan Li
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, China; National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao 266237, China
| | - Jingyao Qu
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, China; National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao 266237, China.
| | - Lushan Wang
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, China.
| | - Jian Zhao
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, China.
| | - Yinbo Qu
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, China; National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao 266237, China.
| | - Yuqi Qin
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, China; National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao 266237, China.
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19
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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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20
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Dai S, Holt MV, Horton JR, Woodcock CB, Patel A, Zhang X, Young NL, Wilkinson AW, Cheng X. Characterization of SETD3 methyltransferase-mediated protein methionine methylation. J Biol Chem 2020; 295:10901-10910. [PMID: 32503840 DOI: 10.1074/jbc.ra120.014072] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Revised: 06/03/2020] [Indexed: 12/20/2022] Open
Abstract
Most characterized protein methylation events encompass arginine and lysine N-methylation, and only a few cases of protein methionine thiomethylation have been reported. Newly discovered oncohistone mutations include lysine-to-methionine substitutions at positions 27 and 36 of histone H3.3. In these instances, the methionine substitution localizes to the active-site pocket of the corresponding histone lysine methyltransferase, thereby inhibiting the respective transmethylation activity. SET domain-containing 3 (SETD3) is a protein (i.e. actin) histidine methyltransferase. Here, we generated an actin variant in which the histidine target of SETD3 was substituted with methionine. As for previously characterized histone SET domain proteins, the methionine substitution substantially (76-fold) increased binding affinity for SETD3 and inhibited SETD3 activity on histidine. Unexpectedly, SETD3 was active on the substituted methionine, generating S-methylmethionine in the context of actin peptide. The ternary structure of SETD3 in complex with the methionine-containing actin peptide at 1.9 Å resolution revealed that the hydrophobic thioether side chain is packed by the aromatic rings of Tyr312 and Trp273, as well as the hydrocarbon side chain of Ile310 Our results suggest that placing methionine properly in the active site-within close proximity to and in line with the incoming methyl group of SAM-would allow some SET domain proteins to selectively methylate methionine in proteins.
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Affiliation(s)
- Shaobo Dai
- Department of Epigenetics and Molecular Carcinogenesis, University of Texas M. D. Anderson Cancer Center, Houston, Texas, USA
| | - Matthew V Holt
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas, USA
| | - John R Horton
- Department of Epigenetics and Molecular Carcinogenesis, University of Texas M. D. Anderson Cancer Center, Houston, Texas, USA
| | - Clayton B Woodcock
- Department of Epigenetics and Molecular Carcinogenesis, University of Texas M. D. Anderson Cancer Center, Houston, Texas, USA
| | - Anamika Patel
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Xing Zhang
- Department of Epigenetics and Molecular Carcinogenesis, University of Texas M. D. Anderson Cancer Center, Houston, Texas, USA
| | - Nicolas L Young
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas, USA
| | - Alex W Wilkinson
- Department of Biology, Stanford University, Stanford, California, USA
| | - Xiaodong Cheng
- Department of Epigenetics and Molecular Carcinogenesis, University of Texas M. D. Anderson Cancer Center, Houston, Texas, USA
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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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LaeA Controls Citric Acid Production through Regulation of the Citrate Exporter-Encoding cexA Gene in Aspergillus luchuensis mut. kawachii. Appl Environ Microbiol 2020; 86:AEM.01950-19. [PMID: 31862728 DOI: 10.1128/aem.01950-19] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2019] [Accepted: 12/17/2019] [Indexed: 11/20/2022] Open
Abstract
The putative methyltransferase LaeA is a global regulator of metabolic and development processes in filamentous fungi. We characterized the homologous laeA genes of the white koji fungus Aspergillus luchuensis mut. kawachii (A. kawachii) to determine their role in citric acid hyperproduction. The ΔlaeA strain exhibited a significant reduction in citric acid production. Cap analysis gene expression (CAGE) revealed that laeA is required for the expression of a putative citrate exporter-encoding cexA gene, which is critical for citric acid production. Deficient citric acid production by a ΔlaeA strain was rescued by the overexpression of cexA to a level comparable with that of a cexA-overexpressing ΔcexA strain. In addition, chromatin immunoprecipitation coupled with quantitative PCR (ChIP-qPCR) analysis indicated that LaeA regulates the expression of cexA via methylation levels of the histones H3K4 and H3K9. These results indicate that LaeA is involved in citric acid production through epigenetic regulation of cexA in A. kawachii IMPORTANCE A. kawachii has been traditionally used for production of the distilled spirit shochu in Japan. Citric acid produced by A. kawachii plays an important role in preventing microbial contamination during the shochu fermentation process. This study characterized homologous laeA genes; using CAGE, complementation tests, and ChIP-qPCR, it was found that laeA is required for citric acid production through the regulation of cexA in A. kawachii The epigenetic regulation of citric acid production elucidated in this study will be useful for controlling the fermentation processes of shochu.
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23
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Apc.LaeA and Apc.VeA of the velvet complex govern secondary metabolism and morphological development in the echinocandin-producing fungus Aspergillus pachycristatus. J Ind Microbiol Biotechnol 2019; 47:155-168. [PMID: 31758414 DOI: 10.1007/s10295-019-02250-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2019] [Accepted: 11/11/2019] [Indexed: 12/11/2022]
Abstract
The impact of the global secondary metabolite regulators LaeA and VeA on echinocandin B production and morphological development was evaluated in the industrial production strain Aspergillus pachycristatus NRRL 11440. Other representative secondary metabolites were examined as well to determine if the velvet complex functions as in A. nidulans and other species of fungi. Genetic methods used for gene manipulations in A. nidulans were applied to A. pachycristatus. Separate deletions of genes Apc.laeA and Apc.veA resulted in similar yet differing phenotypes in strain NRRL 11440. Disruption of Apc.laeA and Apc.veA significantly reduced, but did not eliminate, the production of echinocandin B. Similar to what has been observed in A. nidulans, the production of sterigmatocystin was nearly eliminated in both mutants. Quantitative reverse transcription PCR analyses confirmed that selected genes of both the echinocandin B and sterigmatocystin gene clusters were down-regulated in both mutant types. The two mutants differed with respect to growth of aerial hyphae, pigmentation, development of conidiophores, conidial germination rate, and ascospore maturation. Further functional annotation of key regulatory genes in A. pachycristatus and related Aspergillus species will improve our understanding of regulation of echinocandin production and co-produced metabolites.
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Li Y, Hu Y, Zhao K, Pan Y, Qu Y, Zhao J, Qin Y. The Indispensable Role of Histone Methyltransferase PoDot1 in Extracellular Glycoside Hydrolase Biosynthesis of Penicillium oxalicum. Front Microbiol 2019; 10:2566. [PMID: 31787956 PMCID: PMC6853848 DOI: 10.3389/fmicb.2019.02566] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 10/23/2019] [Indexed: 11/13/2022] Open
Abstract
Histone methylation is associated with transcription regulation, but its role for glycoside hydrolase (GH) biosynthesis is still poorly understood. We identified the histone H3 lysine 79 (H3K79)-specific methyltransferase PoDot1 in Penicillium oxalicum. PoDot1 affects conidiation by regulating the transcription of key regulators (BrlA, FlbC, and StuA) of asexual development and is required in normal hyphae septum and branch formation by regulating the transcription of five septin-encoding genes, namely, aspA, aspB, aspC, aspD, and aspE. Tandem affinity purification/mass spectrometry showed that PoDot1 has no direct interaction with transcription machinery, but it affects the expressions of extracellular GH genes extensively. The expression of genes (amy15A, amy13A, cel7A/cbh1, cel61A, chi18A, cel3A/bgl1, xyn10A, cel7B/eg1, cel5B/eg2, and cel6A/cbh2) that encode the top 10 GHs was remarkably downregulated by Podot1 deletion (ΔPodot1). Consistent with the decrease in gene transcription level, the activities of amylases and cellulases were significantly decreased in ΔPodot1 mutants in agar (solid) and fermentation (liquid) media. The repression of GH gene expressions caused by PoDot1 deletion was not mediated by key transcription factors, such as AmyR, ClrB, CreA, and XlnR, but was accompanied by defects in global demethylated H3K79 (H3K79me2) and trimethylated H3K79 (H3K79me3). The impairment of H3K79me2 on specific GH gene loci was observed due to PoDot1 deletion. The results implies that defects of H3K79 methylation is the key reason of the downregulated transcription level of GH-encoding genes and reveals the indispensable role of PoDot1 in extracellular GH biosynthesis.
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Affiliation(s)
- Yanan Li
- National Glycoengineering Research Center and State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China.,College of Life Sciences, Henan Agricultural University, Zhengzhou, China.,Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Qingdao, China
| | - Yueyan Hu
- National Glycoengineering Research Center and State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China.,Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Qingdao, China
| | - Kaili Zhao
- National Glycoengineering Research Center and State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China.,Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Qingdao, China
| | - Yunjun Pan
- National Glycoengineering Research Center and State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Yinbo Qu
- National Glycoengineering Research Center and State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China.,Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Qingdao, China
| | - Jian Zhao
- National Glycoengineering Research Center and State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Yuqi Qin
- National Glycoengineering Research Center and State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China.,Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Qingdao, China
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Li Y, Hu Y, Zhu Z, Zhao K, Liu G, Wang L, Qu Y, Zhao J, Qin Y. Normal transcription of cellulolytic enzyme genes relies on the balance between the methylation of H3K36 and H3K4 in Penicillium oxalicum. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:198. [PMID: 31452679 PMCID: PMC6700826 DOI: 10.1186/s13068-019-1539-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 08/06/2019] [Indexed: 05/26/2023]
Abstract
BACKGROUND Enzymatic hydrolysis of lignocellulose by fungi is a key step in global carbon cycle and biomass utilization. Cellulolytic enzyme production is tightly controlled at a transcriptional level. Here, we investigated the roles of different histone lysine methylation modifications in regulating cellulolytic enzyme gene expression, as histone lysine methylation is an important process of chromatin regulation associated with gene transcription. RESULTS PoSet1 and PoSet2 in Penicillium oxalicum, orthologs of Set1 and Set2 in budding yeast, were associated with the methylation of histone H3 lysine 4 (H3K4) and lysine 36 (H3K36). Cellulolytic enzyme production was extensively upregulated by the disruption of PoSet2, but was significantly downregulated by the disruption of PoSet1. We revealed that the activation of cellulolytic enzyme genes was accompanied by the increase of H3K4me3 signal, as well as the decrease of H3K36me1 and H3K36me3 signal on specific gene loci. The repression of cellulolytic enzyme genes was accompanied by the absence of global H3K4me1 and H3K4me2. An increase in the H3K4me3 signal by Poset2 disruption was eliminated by the further disruption of Poset1 and accompanied by the repressed cellulolytic enzyme genes. The active or repressed genes were not always associated with transcription factors. CONCLUSION H3K4 methylation is an active marker of cellulolytic enzyme production, whereas H3K36 methylation is a marker of repression. A crosstalk occurs between H3K36 and H3K4 methylation, and PoSet2 negatively regulates cellulolytic enzyme production by antagonizing the PoSet1-H3K4me3 pathway. The balance of H3K4 and H3K36 methylation is required for the normal transcription of cellulolytic enzyme genes. These results extend our previous understanding that cellulolytic enzyme gene transcription is primarily controlled by transcription factors.
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Affiliation(s)
- Yanan Li
- National Glycoengineering Research Center, Shandong University, Qingdao, 266237 China
- State Key Lab of Microbial Technology, Shandong University, Qingdao, 266237 China
| | - Yueyan Hu
- National Glycoengineering Research Center, Shandong University, Qingdao, 266237 China
- State Key Lab of Microbial Technology, Shandong University, Qingdao, 266237 China
| | - Zhu Zhu
- National Glycoengineering Research Center, Shandong University, Qingdao, 266237 China
- State Key Lab of Microbial Technology, Shandong University, Qingdao, 266237 China
| | - Kaili Zhao
- National Glycoengineering Research Center, Shandong University, Qingdao, 266237 China
- State Key Lab of Microbial Technology, Shandong University, Qingdao, 266237 China
| | - Guodong Liu
- National Glycoengineering Research Center, Shandong University, Qingdao, 266237 China
- State Key Lab of Microbial Technology, Shandong University, Qingdao, 266237 China
| | - Lushan Wang
- National Glycoengineering Research Center, Shandong University, Qingdao, 266237 China
| | - Yinbo Qu
- National Glycoengineering Research Center, Shandong University, Qingdao, 266237 China
- State Key Lab of Microbial Technology, Shandong University, Qingdao, 266237 China
| | - Jian Zhao
- National Glycoengineering Research Center, Shandong University, Qingdao, 266237 China
| | - Yuqi Qin
- National Glycoengineering Research Center, Shandong University, Qingdao, 266237 China
- State Key Lab of Microbial Technology, Shandong University, Qingdao, 266237 China
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Hautbergue T, Jamin EL, Debrauwer L, Puel O, Oswald IP. From genomics to metabolomics, moving toward an integrated strategy for the discovery of fungal secondary metabolites. Nat Prod Rep 2019; 35:147-173. [PMID: 29384544 DOI: 10.1039/c7np00032d] [Citation(s) in RCA: 96] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Fungal secondary metabolites are defined by bioactive properties that ensure adaptation of the fungus to its environment. Although some of these natural products are promising sources of new lead compounds especially for the pharmaceutical industry, others pose risks to human and animal health. The identification of secondary metabolites is critical to assessing both the utility and risks of these compounds. Since fungi present biological specificities different from other microorganisms, this review covers the different strategies specifically used in fungal studies to perform this critical identification. Strategies focused on the direct detection of the secondary metabolites are firstly reported. Particularly, advances in high-throughput untargeted metabolomics have led to the generation of large datasets whose exploitation and interpretation generally require bioinformatics tools. Then, the genome-based methods used to study the entire fungal metabolic potential are reported. Transcriptomic and proteomic tools used in the discovery of fungal secondary metabolites are presented as links between genomic methods and metabolomic experiments. Finally, the influence of the culture environment on the synthesis of secondary metabolites by fungi is highlighted as a major factor to consider in research on fungal secondary metabolites. Through this review, we seek to emphasize that the discovery of natural products should integrate all of these valuable tools. Attention is also drawn to emerging technologies that will certainly revolutionize fungal research and to the use of computational tools that are necessary but whose results should be interpreted carefully.
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Affiliation(s)
- T Hautbergue
- Toxalim (Research Centre in Food Toxicology) Université de Toulouse, INRA, ENVT, INP-Purpan, UPS, F-31027 Toulouse, France.
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27
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Bayram ÖS, Dettmann A, Karahoda B, Moloney NM, Ormsby T, McGowan J, Cea-Sánchez S, Miralles-Durán A, Brancini GTP, Luque EM, Fitzpatrick DA, Cánovas D, Corrochano LM, Doyle S, Selker EU, Seiler S, Bayram Ö. Control of Development, Secondary Metabolism and Light-Dependent Carotenoid Biosynthesis by the Velvet Complex of Neurospora crassa. Genetics 2019; 212:691-710. [PMID: 31068340 PMCID: PMC6614901 DOI: 10.1534/genetics.119.302277] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 05/04/2019] [Indexed: 01/24/2023] Open
Abstract
Neurospora crassa is an established reference organism to investigate carotene biosynthesis and light regulation. However, there is little evidence of its capacity to produce secondary metabolites. Here, we report the role of the fungal-specific regulatory velvet complexes in development and secondary metabolism (SM) in N. crassa Three velvet proteins VE-1, VE-2, VOS-1, and a putative methyltransferase LAE-1 show light-independent nucleocytoplasmic localization. Two distinct velvet complexes, a heterotrimeric VE-1/VE-2/LAE-1 and a heterodimeric VE-2/VOS-1 are found in vivo The heterotrimer-complex, which positively regulates sexual development and represses asexual sporulation, suppresses siderophore coprogen production under iron starvation conditions. The VE-1/VE-2 heterodimer controls carotene production. VE-1 regulates the expression of >15% of the whole genome, comprising mainly regulatory and developmental features. We also studied intergenera functions of the velvet complex through complementation of Aspergillus nidulans veA, velB, laeA, vosA mutants with their N. crassa orthologs ve-1, ve-2, lae-1, and vos-1, respectively. Expression of VE-1 and VE-2 in A. nidulans successfully substitutes the developmental and SM functions of VeA and VelB by forming two functional chimeric velvet complexes in vivo, VelB/VE-1/LaeA and VE-2/VeA/LaeA, respectively. Reciprocally, expression of veA restores the phenotypes of the N. crassa ve-1 mutant. All N. crassa velvet proteins heterologously expressed in A. nidulans are localized to the nuclear fraction independent of light. These data highlight the conservation of the complex formation in N. crassa and A. nidulans However, they also underline the intergenera similarities and differences of velvet roles according to different life styles, niches and ontogenetic processes.
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Affiliation(s)
| | - Anne Dettmann
- Institute for Biology II, Molecular Plant Physiology, Albert-Ludwigs-University 79104 Freiburg, Germany
| | - Betim Karahoda
- Department of Biology, Maynooth University, Co. Kildare, W23 F2H6, Ireland
| | - Nicola M Moloney
- Department of Biology, Maynooth University, Co. Kildare, W23 F2H6, Ireland
| | - Tereza Ormsby
- Institute of Molecular Biology, University of Oregon, Eugene, 97403 Oregon
| | - Jamie McGowan
- Department of Biology, Maynooth University, Co. Kildare, W23 F2H6, Ireland
| | - Sara Cea-Sánchez
- Departmento de Genética, Facultad de Biologia, Universidad de Sevilla, 41012 Sevilla, Spain
| | | | - Guilherme T P Brancini
- Departmento de Genética, Facultad de Biologia, Universidad de Sevilla, 41012 Sevilla, Spain
| | - Eva M Luque
- Departmento de Genética, Facultad de Biologia, Universidad de Sevilla, 41012 Sevilla, Spain
| | | | - David Cánovas
- Departmento de Genética, Facultad de Biologia, Universidad de Sevilla, 41012 Sevilla, Spain
| | - Luis M Corrochano
- Departmento de Genética, Facultad de Biologia, Universidad de Sevilla, 41012 Sevilla, Spain
| | - Sean Doyle
- Department of Biology, Maynooth University, Co. Kildare, W23 F2H6, Ireland
| | - Eric U Selker
- Institute of Molecular Biology, University of Oregon, Eugene, 97403 Oregon
| | - Stephan Seiler
- Institute for Biology II, Molecular Plant Physiology, Albert-Ludwigs-University 79104 Freiburg, Germany
| | - Özgür Bayram
- Department of Biology, Maynooth University, Co. Kildare, W23 F2H6, Ireland
- Human Health Research Institute, Maynooth University, Co. Kildare, W23 F2H6, Ireland
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28
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Ejmal MA, Holland DJ, MacDiarmid RM, Pearson MN. The Effect of Aspergillus Thermomutatus Chrysovirus 1 on the Biology of Three Aspergillus Species. Viruses 2018; 10:E539. [PMID: 30279352 PMCID: PMC6213286 DOI: 10.3390/v10100539] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 09/25/2018] [Accepted: 09/29/2018] [Indexed: 12/16/2022] Open
Abstract
This study determined the effects of Aspergillus thermomutatus chrysovirus 1 (AthCV1), isolated from Aspergillus thermomutatus, on A. fumigatus, A. nidulans and A. niger. Protoplasts of virus-free isolates of A. fumigatus, A. nidulans and A. niger were transfected with purified AthCV1 particles and the phenotype, growth and sporulation of the isogenic AthCV1-free and AthCV1-infected lines assessed at 20 °C and 37 °C and gene expression data collected at 37 °C. AthCV1-free and AthCV1-infected A. fumigatus produced only conidia at both temperatures but more than ten-fold reduced compared to the AthCV1-infected line. Conidiation was also significantly reduced in infected lines of A. nidulans and A. niger at 37 °C. AthCV1-infected lines of A. thermomutatus and A. nidulans produced large numbers of ascospores at both temperatures, whereas the AthCV1-free line of the former did not produce ascospores. AthCV1-infected lines of all species developed sectoring phenotypes with sclerotia produced in aconidial sectors of A. niger at 37 °C. AthCV1 was detected in 18% of sclerotia produced by AthCV1-infected A. niger and 31% of ascospores from AthCV1-infected A. nidulans. Transcriptome analysis of the naturally AthCV1-infected A. thermomutatus and the three AthCV1-transfected Aspergillus species showed altered gene expression as a result of AthCV1-infection. The results demonstrate that AthCV1 can infect a range of Aspergillus species resulting in reduced sporulation, a potentially useful attribute for a biological control agent.
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Affiliation(s)
- Mahjoub A Ejmal
- School of Biological Sciences, the University of Auckland, Auckland 1142 New Zealand.
| | - David J Holland
- Infectious Diseases Unit, Division of Medicine, Middlemore Hospital, Auckland 1640, New Zealand.
| | - Robin M MacDiarmid
- School of Biological Sciences, the University of Auckland, Auckland 1142 New Zealand.
- Plant and Food Research, Auckland 1142, New Zealand.
| | - Michael N Pearson
- School of Biological Sciences, the University of Auckland, Auckland 1142 New Zealand.
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29
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Transcription Factors Controlling Primary and Secondary Metabolism in Filamentous Fungi: The β-Lactam Paradigm. FERMENTATION-BASEL 2018. [DOI: 10.3390/fermentation4020047] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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30
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Jain S, Wiemann P, Thill E, Williams B, Keller NP, Kabbage M. A Bcl-2 Associated Athanogene ( bagA) Modulates Sexual Development and Secondary Metabolism in the Filamentous Fungus Aspergillus nidulans. Front Microbiol 2018; 9:1316. [PMID: 29963036 PMCID: PMC6013550 DOI: 10.3389/fmicb.2018.01316] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 05/30/2018] [Indexed: 02/06/2023] Open
Abstract
The Bcl-2 associated athanogene (Bag) family is a multifunctional group of proteins distinguished by a conserved region known as the Bag domain (BD). Herein, we discuss the discovery and characterization of a Bag protein in the model genetic fungus Aspergillus nidulans, we designated BagA. BagA shares striking similarities in 3D structure, domain organization, amino acid properties, and Hsp70 binding surfaces to animal and plant Bags. While Hsp70 binding is a common feature of Bag proteins, our experimental evidence shows that BagA does not cooperate with A. nidulans Hsp70s, suggesting this association may not be a universal feature of Bag proteins. Gene expression of bagA was strongly induced during sexual development suggesting a role in developmental processes. Accordingly, the deletion of bagA (ΔbagA) negatively impacted sexual development, while its overexpression resulted in constitutive induction of sexual fruiting bodies and spores. Asexual and sexual development was linked to secondary metabolism in A. nidulans. Our data show that the deletion of bagA also provoked an altered secondary metabolite (SM) profile in both sexual and vegetative growth phases. Indeed, LC-MS analysis showed a significant enrichment of SMs in ΔbagA, including novel metabolites not produced by wild type strain. Enrichment of SMs in ΔbagA strain is particularly intriguing and suggest that altering cellular homeostasis can be used as a provocative strategy to activate cryptic metabolites and uncover novel bioactive compounds. Overall, our results indicate that Bag proteins in filamentous fungi share developmental regulatory roles with their animal and plant counterparts. We also show a potentially unique role for BagA in modulating secondary metabolism in A. nidulans. To our knowledge, this study provides a first insight into Bag function in filamentous fungi.
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Affiliation(s)
- Sachin Jain
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, WI, United States
| | - Philipp Wiemann
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, United States
| | - Elizabeth Thill
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, WI, United States
| | - Brett Williams
- Centre for Tropical Crops and Biocommodities, Queensland University of Technology, Brisbane, QLD, Australia
| | - Nancy P Keller
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, United States.,Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, United States
| | - Mehdi Kabbage
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, WI, United States
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31
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Nie X, Li B, Wang S. Epigenetic and Posttranslational Modifications in Regulating the Biology of Aspergillus Species. ADVANCES IN APPLIED MICROBIOLOGY 2018; 105:191-226. [PMID: 30342722 DOI: 10.1016/bs.aambs.2018.05.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Epigenetic and posttranslational modifications have been proved to participate in multiple cellular processes and suggested to be an important regulatory mechanism on transcription of genes in eukaryotes. However, our knowledge about epigenetic and posttranslational modifications mainly comes from the studies of yeasts, plants, and animals. Recently, epigenetic and posttranslational modifications have also raised concern for the relevance of regulating fungal biology in Aspergillus. Emerging evidence indicates that these modifications could be a connection between genetic elements and environmental factors, and their combined effects may finally lead to fungal phenotypical changes. This article describes the advances in typical DNA and protein modifications in the genus Aspergillus, focusing on methylation, acetylation, phosphorylation, ubiquitination, sumoylation, and neddylation.
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Affiliation(s)
- Xinyi Nie
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Bowen Li
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China; State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, China
| | - Shihua Wang
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
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Niehaus EM, Rindermann L, Janevska S, Münsterkötter M, Güldener U, Tudzynski B. Analysis of the global regulator Lae1 uncovers a connection between Lae1 and the histone acetyltransferase HAT1 in Fusarium fujikuroi. Appl Microbiol Biotechnol 2017; 102:279-295. [PMID: 29080998 DOI: 10.1007/s00253-017-8590-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 10/17/2017] [Accepted: 10/18/2017] [Indexed: 01/08/2023]
Abstract
The fungus Fusarium fujikuroi causes "bakanae" disease of rice due to its ability to produce gibberellins (GAs), a family of plant hormones. Recent genome sequencing revealed the genetic capacity for the biosynthesis of 46 additional secondary metabolites besides the industrially produced GAs. Among them are the pigments bikaverin and fusarubins, as well as mycotoxins, such as fumonisins, fusarin C, beauvericin, and fusaric acid. However, half of the potential secondary metabolite gene clusters are silent. In recent years, it has been shown that the fungal specific velvet complex is involved in global regulation of secondary metabolism in several filamentous fungi. We have previously shown that deletion of the three components of the F. fujikuroi velvet complex, vel1, vel2, and lae1, almost totally abolished biosynthesis of GAs, fumonisins and fusarin C. Here, we present a deeper insight into the genome-wide regulatory impact of Lae1 on secondary metabolism. Over-expression of lae1 resulted in de-repression of GA biosynthetic genes under otherwise repressing high nitrogen conditions demonstrating that the nitrogen repression is overcome. In addition, over-expression of one of five tested histone acetyltransferase genes, HAT1, was capable of returning GA gene expression and GA production to the GA-deficient Δlae1 mutant. Deletion and over-expression of HAT1 in the wild type resulted in downregulation and upregulation of GA gene expression, respectively, indicating that HAT1 together with Lae1 plays an essential role in the regulation of GA biosynthesis.
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Affiliation(s)
- Eva-Maria Niehaus
- Institute for Plant Biology and Biotechnology, Westfälische Wilhelms University Münster, Schlossplatz 8, 48143, Münster, Germany.,Institute of Food Chemistry, Westfälische Wilhelms University Münster, Corrensstr. 45, 48149, Münster, Germany
| | - Lena Rindermann
- Institute for Plant Biology and Biotechnology, Westfälische Wilhelms University Münster, Schlossplatz 8, 48143, Münster, Germany
| | - Slavica Janevska
- Institute for Plant Biology and Biotechnology, Westfälische Wilhelms University Münster, Schlossplatz 8, 48143, Münster, Germany
| | - Martin Münsterkötter
- Institute of Bioinformatics and Systems Biology, Helmholtz Zentrum München, Germany Research Center for Environmental Health (GmbH), Ingolstädter Landstraße 1, 85764, Neuherberg, Germany
| | - Ulrich Güldener
- Chair of Genome-oriented Bioinformatics, TUM School of Life Sciences Weihenstephan, Technical University of Munich, 85354, Freising, Germany
| | - Bettina Tudzynski
- Institute for Plant Biology and Biotechnology, Westfälische Wilhelms University Münster, Schlossplatz 8, 48143, Münster, Germany.
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Feng X, Ramamoorthy V, Pandit SS, Prieto A, Espeso EA, Calvo AM. cpsA regulates mycotoxin production, morphogenesis and cell wall biosynthesis in the fungus Aspergillus nidulans. Mol Microbiol 2017; 105:1-24. [PMID: 28370587 PMCID: PMC5506848 DOI: 10.1111/mmi.13682] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 03/21/2017] [Accepted: 03/26/2017] [Indexed: 01/07/2023]
Abstract
The model fungus Aspergillus nidulans synthesizes numerous secondary metabolites, including sterigmatocystin (ST). The production of this toxin is positively controlled by the global regulator veA. In the absence of veA (ΔveA), ST biosynthesis is blocked. Previously, we performed random mutagenesis in a ΔveA strain and identified revertant mutants able to synthesize ST, among them RM1. Complementation of RM1 with a genomic library revealed that the mutation occurred in a gene designated as cpsA. While in the ΔveA genetic background cpsA deletion restores ST production, in a veA wild-type background absence of cpsA reduces and delays ST biosynthesis decreasing the expression of ST genes. Furthermore, cpsA is also necessary for the production of other secondary metabolites, including penicillin, affecting the expression of PN genes. In addition, cpsA is necessary for normal asexual and sexual development. Chemical and microscopy analyses revealed that CpsA is found in cytoplasmic vesicles and it is required for normal cell wall composition and integrity, affecting adhesion capacity and oxidative stress sensitivity. The conservation of cpsA in Ascomycetes suggests that cpsA homologs might have similar roles in other fungal species.
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Affiliation(s)
- Xuehuan Feng
- Department of Biological Sciences, Northern Illinois University, Dekalb, IL 60115, USA
| | - Vellaisamy Ramamoorthy
- Department of Biological Sciences, Northern Illinois University, Dekalb, IL 60115, USA,Dept. of Plant Pathology Agricultural College and Research Institute Killikulam, Vallanadu - 628 252 Thoothukudi District Tamil Nadu, India
| | - Sandesh S. Pandit
- Department of Biological Sciences, Northern Illinois University, Dekalb, IL 60115, USA
| | - Alicia Prieto
- Centro de Investigaciones Biológicas, CSIC, Madrid, Spain
| | | | - Ana M. Calvo
- Department of Biological Sciences, Northern Illinois University, Dekalb, IL 60115, USA,Author to whom correspondence should be addressed [telephone: (815) 753-0451]; fax (815) 753-0461; ]
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Li Y, Zheng X, Zhang X, Bao L, Zhu Y, Qu Y, Zhao J, Qin Y. The Different Roles of Penicillium oxalicum LaeA in the Production of Extracellular Cellulase and β-xylosidase. Front Microbiol 2016; 7:2091. [PMID: 28066400 PMCID: PMC5177634 DOI: 10.3389/fmicb.2016.02091] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 12/09/2016] [Indexed: 12/16/2022] Open
Abstract
Cellulolytic enzyme hydrolysis of lignocellulose biomass to release fermentable sugars is one of the key steps in biofuel refining. Gene expression of fungal cellulolytic enzymes is tightly controlled at the transcriptional level. Key transcription factors such as activator ClrB/CLR2 and XlnR/XYR1, as well as repressor CreA/CRE1 play crucial roles in this process. The putative protein methyltransferase LaeA/LAE1 has also been reported to regulate the gene expression of the cellulolytic enzyme. The formation and gene expression of the cellulolytic enzyme was compared among Penicillium oxalicum wild type (WT) and seven mutants, including ΔlaeA (deletion of laeA), OEclrB (clrB overexpression), OEclrBΔlaeA (clrB overexpression with deletion of laeA), OExlnR (xlnR overexpression), OExlnRΔlaeA (xlnR overexpression with deletion of laeA), ΔcreA (deletion of creA), and ΔcreAΔlaeA (double deletion of creA and laeA). Results revealed that LaeA extensively affected the expression of glycoside hydrolase genes. The expression of genes that encoded the top 10 glycoside hydrolases assayed in secretome was remarkably downregulated especially in later phases of prolonged batch cultures by the deletion of laeA. Cellulase synthesis of four mutants ΔlaeA, OEclrBΔlaeA, OExlnRΔlaeA, and ΔcreAΔlaeA was repressed remarkably compared with their parent strains WT, OEclrB, OExlnR, and ΔcreA, respectively. The overexpression of clrB or xlnR could not rescue the impairment of cellulolytic enzyme gene expression and cellulase synthesis when LaeA was absent, suggesting that LaeA was necessary for the expression of cellulolytic enzyme gene activated by ClrB or XlnR. In contrast to LaeA positive roles in regulating prominent cellulase and hemicellulase, the extracellular β-xylosidase formation was negatively regulated by LaeA. The extracellular β-xylosidase activities improved over 5-fold in the OExlnRΔlaeA mutant compared with that of WT, and the expression of prominent β-xylosidase gene xyl3A was activated remarkably. The cumulative effect of LaeA and transcription factor XlnR has potential applications in the production of more β-xylosidase.
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Affiliation(s)
- Yanan Li
- State Key Lab of Microbial Technology and National Glycoengineering Research Center, Shandong UniversityJinan, China; Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong UniversityJinan, China
| | - Xiaoju Zheng
- State Key Lab of Microbial Technology and National Glycoengineering Research Center, Shandong University Jinan, China
| | - Xiujun Zhang
- State Key Lab of Microbial Technology and National Glycoengineering Research Center, Shandong University Jinan, China
| | - Longfei Bao
- State Key Lab of Microbial Technology and National Glycoengineering Research Center, Shandong University Jinan, China
| | - Yingying Zhu
- State Key Lab of Microbial Technology and National Glycoengineering Research Center, Shandong University Jinan, China
| | - Yinbo Qu
- State Key Lab of Microbial Technology and National Glycoengineering Research Center, Shandong University Jinan, China
| | - Jian Zhao
- State Key Lab of Microbial Technology and National Glycoengineering Research Center, Shandong University Jinan, China
| | - Yuqi Qin
- State Key Lab of Microbial Technology and National Glycoengineering Research Center, Shandong UniversityJinan, China; Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong UniversityJinan, China
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Chettri P, Bradshaw RE. LaeA negatively regulates dothistromin production in the pine needle pathogen Dothistroma septosporum. Fungal Genet Biol 2016; 97:24-32. [PMID: 27818262 DOI: 10.1016/j.fgb.2016.11.001] [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: 08/22/2016] [Revised: 10/30/2016] [Accepted: 11/01/2016] [Indexed: 01/03/2023]
Abstract
In filamentous fungi both pathway-specific and global regulators regulate genes involved in the biosynthesis of secondary metabolites. LaeA is a global regulator that was named for its mutant phenotype, loss of aflR expression, due to its effect on the aflatoxin-pathway regulator AflR in Aspergillus spp. The pine needle pathogen Dothistroma septosporum produces a polyketide virulence factor, dothistromin, that is chemically related to aflatoxin and whose pathway genes are also regulated by an ortholog of AflR. However, dothistromin biosynthesis is distinctive because it is switched on during early (rather than late) exponential growth phase and the genes are dispersed in six loci across one chromosome instead of being clustered. It was therefore of interest to determine whether the function of the global regulator LaeA is conserved in D. septosporum. To address this question, a LaeA ortholog (DsLaeA) was identified and its function analyzed in D. septosporum. In contrast to aflatoxin production in Aspergillus spp., deletion of DsLaeA resulted in enhanced dothistromin production and increased expression of the pathway regulatory gene DsAflR. Although expression of other putative secondary metabolite genes in D. septosporum showed a range of different responses to loss of DsLaeA function, thin layer chromatography revealed increased levels of a previously unknown metabolite in DsLaeA mutants. In addition, these mutants exhibited reduced asexual sporulation, germination and hydrophobicity. Our data suggest that although the developmental regulatory role of DsLaeA is conserved, its role in the regulation of secondary metabolism differs from that of LaeA in A. nidulans and appears to be species specific. This study provides a step towards understanding fundamental differences in regulation of clustered and fragmented groups of secondary metabolite genes that may shed light on understanding functional adaptation in secondary metabolism.
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Affiliation(s)
- Pranav Chettri
- Bio-Protection Research Centre, Institute of Fundamental Sciences, Massey University, Palmerston North 4474, New Zealand
| | - Rosie E Bradshaw
- Bio-Protection Research Centre, Institute of Fundamental Sciences, Massey University, Palmerston North 4474, New Zealand.
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Jiang T, Wang M, Li L, Si J, Song B, Zhou C, Yu M, Wang X, Zhang Y, Ding G, Zou Z. Overexpression of the Global Regulator LaeA in Chaetomium globosum Leads to the Biosynthesis of Chaetoglobosin Z. JOURNAL OF NATURAL PRODUCTS 2016; 79:2487-2494. [PMID: 27759375 DOI: 10.1021/acs.jnatprod.6b00333] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Overexpression of laeA in Chaetomium globosum CBS148.51 up-regulated expression of the chaetoglobosin gene cluster and resulted in the isolation of a new cytochalasan, chaetoglobosin Z (1), together with six known analogues, chaetoglobosins A (2), B (3), D (4), E (5), O (6), and V (7). RT-PCR analysis confirmed that the key genes in the chaetoglobosin gene cluster were significantly up-regulated. The structure of the new compound chaetoglobosin Z (1) was elucidated using NMR data. The relative and absolute configurations were determined by NOESY and electronic circular dichroism combined with quantum-chemical calculations adopting time-dependent density functional theory methods, respectively. These compounds displayed strong biological effects against the HepG 2 cell line compared with the positive control. The results further supported that LaeA is a global regulator that could up-regulate and/or activate cryptic gene clusters to produce new secondary metabolites.
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Affiliation(s)
- Tao Jiang
- Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development , Beijing, 100193, People's Republic of China
| | - Menghua Wang
- Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development , Beijing, 100193, People's Republic of China
| | - Li Li
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica , Beijing 100050, People's Republic of China
| | - Jinguang Si
- Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development , Beijing, 100193, People's Republic of China
- School of Pharmacy, Henan University of Traditional Chinese Medicine , Zhengzhou 450046, People's Republic of China
| | - Bo Song
- Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development , Beijing, 100193, People's Republic of China
| | - Cao Zhou
- Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development , Beijing, 100193, People's Republic of China
| | - Meng Yu
- Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development , Beijing, 100193, People's Republic of China
| | - Xuewei Wang
- Institute of Microbiology, Chinese Academy of Sciences , Beijing 100090, People's Republic of China
| | - Yonggang Zhang
- Key Laboratory for Applied Microbiology of Shandong Province , Jinan 250014, People's Republic of China
| | - Gang Ding
- Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development , Beijing, 100193, People's Republic of China
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica , Beijing 100050, People's Republic of China
| | - Zhongmei Zou
- Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development , Beijing, 100193, People's Republic of China
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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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Linde T, Zoglowek M, Lübeck M, Frisvad JC, Lübeck PS. The global regulator LaeA controls production of citric acid and endoglucanases in Aspergillus carbonarius. J Ind Microbiol Biotechnol 2016; 43:1139-47. [PMID: 27169528 DOI: 10.1007/s10295-016-1781-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Accepted: 04/28/2016] [Indexed: 01/11/2023]
Abstract
The global regulatory protein LaeA is known for regulating the production of many kinds of secondary metabolites in Aspergillus species, as well as sexual and asexual reproduction, and morphology. In Aspergillus carbonarius, it has been shown that LaeA regulates production of ochratoxin. We have investigated the regulatory effect of LaeA on production of citric acid and cellulolytic enzymes in A. carbonarius. Two types of A. carbonarius strains, having laeA knocked out or overexpressed, were constructed and tested in fermentation. The knockout of laeA significantly decreased the production of citric acid and endoglucanases, but did not reduce the production of beta-glucosidases or xylanases. The citric acid accumulation was reduced with 74-96 % compared to the wild type. The endoglucanase activity was reduced with 51-78 %. Overexpression of LaeA seemed not to have an effect on citric acid production or on cellulose or xylanase activity.
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Affiliation(s)
- Tore Linde
- Section for Sustainable Biotechnology, Aalborg University, A.C. Meyers Vaenge 15, 2450, Copenhagen SV, Denmark
| | - Marta Zoglowek
- Carlsberg Research Laboratory, Yeast & Fermentation, Group Commercial, Gamle Carlsberg Vej 4, 1799, Copenhagen V, Denmark
| | - Mette Lübeck
- Section for Sustainable Biotechnology, Aalborg University, A.C. Meyers Vaenge 15, 2450, Copenhagen SV, Denmark
| | - Jens Christian Frisvad
- DTU, Institute for System-biologi, Fungal Chemodiversity, Søltofts Plads, 2800, Kgs. Lyngby, Denmark
| | - Peter Stephensen Lübeck
- Section for Sustainable Biotechnology, Aalborg University, A.C. Meyers Vaenge 15, 2450, Copenhagen SV, Denmark.
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Yang K, Liang L, Ran F, Liu Y, Li Z, Lan H, Gao P, Zhuang Z, Zhang F, Nie X, Kalayu Yirga S, Wang S. The DmtA methyltransferase contributes to Aspergillus flavus conidiation, sclerotial production, aflatoxin biosynthesis and virulence. Sci Rep 2016; 6:23259. [PMID: 26979781 PMCID: PMC4793245 DOI: 10.1038/srep23259] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 02/25/2016] [Indexed: 11/09/2022] Open
Abstract
DNA methylation is essential for epigenetic regulation of gene transcription and development in many animals, plants and fungi. We investigated whether DNA methylation plays a role in the development and secondary metabolism of Aspergillus flavus, identified the DmtA methyltransferase from A. flavus, and produced a dmtA knock-out mutant by replacing the dmtA coding sequence with the pyrG selectable marker. The A. flavus dmtA null mutant lines produced white fluffy mycelium in liquid medium, and displayed a slightly flavescent conidial pigmentation compared with the normal yellow of the wild-type strain when grown on agar. The ΔdmtA lines exhibited decreased conidiation and aflatoxin (AF) biosynthesis, compared with the wild-type line, suggesting that the DmtA knock-out affected the transcriptional level of genes in the AF cluster. In particular, sclerotia development and host colonization were altered in the dmtA null mutants. Green fluorescent protein tagging at the C-terminus of DmtA showed that DmtA localized to the nucleus and cytoplasm. DNA methylation content measurements in the dmtA mutants revealed no widespread DNA methylation in the mutants or wild-type lines. Thus, our findings suggest that DmtA, apart from being a C-5 cytosine methyltransferase in A. flavus, contributes to asexual development, aflatoxin biosynthesis, sclerotial production and virulence.
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Affiliation(s)
- Kunlong Yang
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Linlin Liang
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Fanlei Ran
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Yinghang Liu
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Zhenguo Li
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Huahui Lan
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Peili Gao
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Zhenhong Zhuang
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Feng Zhang
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Xinyi Nie
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Shimuye Kalayu Yirga
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Shihua Wang
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China
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Aghcheh RK, Kubicek CP. Epigenetics as an emerging tool for improvement of fungal strains used in biotechnology. Appl Microbiol Biotechnol 2015; 99:6167-81. [PMID: 26115753 DOI: 10.1007/s00253-015-6763-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Revised: 06/07/2015] [Accepted: 06/10/2015] [Indexed: 10/23/2022]
Abstract
Filamentous fungi are today a major source of industrial biotechnology for the production of primary and secondary metabolites, as well as enzymes and recombinant proteins. All of them have undergone extensive improvement strain programs, initially by classical mutagenesis and later on by genetic manipulation. Thereby, strategies to overcome rate-limiting or yield-reducing reactions included manipulating the expression of individual genes, their regulatory genes, and also their function. Yet, research of the last decade clearly showed that cells can also undergo heritable changes in gene expression that do not involve changes in the underlying DNA sequences (=epigenetics). This involves three levels of regulation: (i) DNA methylation, (ii) chromatin remodeling by histone modification, and (iii) RNA interference. The demonstration of the occurrence of these processes in fungal model organisms such as Aspergillus nidulans and Neurospora crassa has stimulated its recent investigation as a tool for strain improvement in industrially used fungi. This review describes the progress that has thereby been obtained.
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Affiliation(s)
- Razieh Karimi Aghcheh
- Institute of Chemical Engineering, Vienna University of Technology, Getreidemarkt 9/166-5, 1060, Vienna, Austria,
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Sarikaya-Bayram Ö, Palmer JM, Keller N, Braus GH, Bayram Ö. One Juliet and four Romeos: VeA and its methyltransferases. Front Microbiol 2015; 6:1. [PMID: 25653648 PMCID: PMC4299510 DOI: 10.3389/fmicb.2015.00001] [Citation(s) in RCA: 126] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 01/01/2015] [Indexed: 11/19/2022] Open
Abstract
Fungal secondary metabolism has become an important research topic with great biomedical and biotechnological value. In the postgenomic era, understanding the diversity and the molecular control of secondary metabolites (SMs) are two challenging tasks addressed by the research community. Discovery of the LaeA methyltransferase 10 years ago opened up a new horizon on the control of SM research when it was found that expression of many SM gene clusters is controlled by LaeA. While the molecular function of LaeA remains an enigma, discovery of the velvet family proteins as interaction partners further extended the role of the LaeA beyond secondary metabolism. The heterotrimeric VelB–VeA–LaeA complex plays important roles in development, sporulation, secondary metabolism, and pathogenicity. Recently, three other methyltransferases have been found to associate with the velvet complex, the LaeA-like methyltransferase F and the methyltransferase heterodimers VipC–VapB. Interaction of VeA with at least four methyltransferase proteins indicates a molecular hub function for VeA that questions: Is there a VeA supercomplex or is VeA part of a highly dynamic cellular control network with many different partners?
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Affiliation(s)
- Özlem Sarikaya-Bayram
- Department of Biology, Maynooth University, National University of Ireland , Maynooth, Ireland
| | - Jonathan M Palmer
- Center for Forest Mycology Research, Northern Research Station, United States Forest Service , Madison, WI, USA
| | - Nancy Keller
- Department of Medical Microbiology and Immunology, University of Wisconsin at Madison , Madison, WI, USA
| | - Gerhard H Braus
- Department of Molecular Microbiology and Genetics, Georg-August Universität Göttingen , Göttingen, Germany
| | - Özgür Bayram
- Department of Biology, Maynooth University, National University of Ireland , Maynooth, Ireland
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Spitzmüller Z, Kwon NJ, Szilágyi M, Keserű J, Tóth V, Yu JH, Pócsi I, Emri T. γ-Glutamyl transpeptidase (GgtA) of Aspergillus nidulans is not necessary for bulk degradation of glutathione. Arch Microbiol 2014; 197:285-97. [PMID: 25519188 DOI: 10.1007/s00203-014-1057-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Revised: 10/27/2014] [Accepted: 10/28/2014] [Indexed: 12/31/2022]
Abstract
Aspergillus nidulans exhibited high γ-glutamyl transpeptidase (γGT) activity in both carbon-starved and carbon-limited cultures. Glucose repressed, but casein peptone increased γGT production. Null mutation of creA did not influence γGT formation, but the functional meaB was necessary for the γGT induction. Deletion of the AN10444 gene (ggtA) completely eliminated the γGT activity, and the mRNA levels of ggtA showed strong correlation with the observed γGT activities. While ggtA does not contain a canonical signal sequence, the γGT activity was detectable both in the fermentation broth and in the hyphae. Deletion of the ggtA gene did not prevent the depletion of glutathione observed in carbon-starved and carbon-limited cultures. Addition of casein peptone to carbon-starved cultures lowered the formation of reactive species (RS). Deletion of ggtA could hinder this decrease and resulted in elevated RS formation. This effect of γGT on redox homeostasis may explain the reduced cleistothecia formation of ΔggtA strains in surface cultures.
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Affiliation(s)
- Zsolt Spitzmüller
- Department of Biotechnology and Microbiology, Faculty of Science and Technology, University of Debrecen, Egyetem tér 1, Debrecen, H4032, Hungary
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Karimi Aghcheh R, Németh Z, Atanasova L, Fekete E, Paholcsek M, Sándor E, Aquino B, Druzhinina IS, Karaffa L, Kubicek CP. The VELVET A orthologue VEL1 of Trichoderma reesei regulates fungal development and is essential for cellulase gene expression. PLoS One 2014; 9:e112799. [PMID: 25386652 PMCID: PMC4227869 DOI: 10.1371/journal.pone.0112799] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 10/15/2014] [Indexed: 11/25/2022] Open
Abstract
Trichoderma reesei is the industrial producer of cellulases and hemicellulases for biorefinery processes. Their expression is obligatorily dependent on the function of the protein methyltransferase LAE1. The Aspergillus nidulans orthologue of LAE1 - LaeA - is part of the VELVET protein complex consisting of LaeA, VeA and VelB that regulates secondary metabolism and sexual as well as asexual reproduction. Here we have therefore investigated the function of VEL1, the T. reesei orthologue of A. nidulans VeA. Deletion of the T. reesei vel1 locus causes a complete and light-independent loss of conidiation, and impairs formation of perithecia. Deletion of vel1 also alters hyphal morphology towards hyperbranching and formation of thicker filaments, and with consequently reduced growth rates. Growth on lactose as a sole carbon source, however, is even more strongly reduced and growth on cellulose as a sole carbon source eliminated. Consistent with these findings, deletion of vel1 completely impaired the expression of cellulases, xylanases and the cellulase regulator XYR1 on lactose as a cellulase inducing carbon source, but also in resting mycelia with sophorose as inducer. Our data show that in T. reesei VEL1 controls sexual and asexual development, and this effect is independent of light. VEL1 is also essential for cellulase gene expression, which is consistent with the assumption that their regulation by LAE1 occurs by the VELVET complex.
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Affiliation(s)
- Razieh Karimi Aghcheh
- Institute of Chemical Engineering, Research Division Biotechnology and Microbiology, Microbiology Group, Vienna University of Technology, 1060 Vienna, Austria
| | - Zoltán Németh
- Department of Biochemical Engineering, Faculty of Sciences and Technology, University of Debrecen, H-4032 Debrecen, Hungary
| | - Lea Atanasova
- Institute of Chemical Engineering, Research Division Biotechnology and Microbiology, Microbiology Group, Vienna University of Technology, 1060 Vienna, Austria
| | - Erzsébet Fekete
- Department of Biochemical Engineering, Faculty of Sciences and Technology, University of Debrecen, H-4032 Debrecen, Hungary
| | - Melinda Paholcsek
- Department of Human Genetics, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - Erzsébet Sándor
- Faculty of Agricultural and Food Science and Environmental Management, Institute of Food Science, H-4032 Debrecen, Hungary
| | - Benigno Aquino
- Institute of Chemical Engineering, Research Division Biotechnology and Microbiology, Microbiology Group, Vienna University of Technology, 1060 Vienna, Austria
| | - Irina S. Druzhinina
- Institute of Chemical Engineering, Research Division Biotechnology and Microbiology, Microbiology Group, Vienna University of Technology, 1060 Vienna, Austria
- Austrian Center of Industrial Biotechnology, c/o Institute of Chemical Engineering, Vienna University of Technology, 1060 Vienna, Austria
| | - Levente Karaffa
- Department of Biochemical Engineering, Faculty of Sciences and Technology, University of Debrecen, H-4032 Debrecen, Hungary
| | - Christian P. Kubicek
- Institute of Chemical Engineering, Research Division Biotechnology and Microbiology, Microbiology Group, Vienna University of Technology, 1060 Vienna, Austria
- Austrian Center of Industrial Biotechnology, 8010 Graz, Austria
- * E-mail:
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Yang K, Zhuang Z, Zhang F, Song F, Zhong H, Ran F, Yu S, Xu G, Lan F, Wang S. Inhibition of aflatoxin metabolism and growth ofAspergillus flavusin liquid culture by a DNA methylation inhibitor. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2014; 32:554-63. [DOI: 10.1080/19440049.2014.972992] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Gerke J, Braus GH. Manipulation of fungal development as source of novel secondary metabolites for biotechnology. Appl Microbiol Biotechnol 2014; 98:8443-55. [PMID: 25142695 PMCID: PMC4192562 DOI: 10.1007/s00253-014-5997-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Revised: 07/25/2014] [Accepted: 07/28/2014] [Indexed: 12/19/2022]
Abstract
Fungal genomics revealed a large potential of yet-unexplored secondary metabolites, which are not produced during vegetative growth. The discovery of novel bioactive compounds is increasingly gaining importance. The high number of resistances against established antibiotics requires novel drugs to counteract increasing human and animal mortality rates. In addition, growth of plant pathogens has to be controlled to minimize harvest losses. An additional critical issue is the post-harvest production of deleterious mycotoxins. Fungal development and secondary metabolite production are linked processes. Therefore, molecular regulators of development might be suitable to discover new bioactive fungal molecules or to serve as targets to control fungal growth, development, or secondary metabolite production. The fungal impact is relevant as well for our healthcare systems as for agriculture. We propose here to use the knowledge about mutant strains discovered in fungal model systems for a broader application to detect and explore new fungal drugs or toxins. As examples, mutant strains impaired in two conserved eukaryotic regulatory complexes are discussed. The COP9 signalosome (CSN) and the velvet complex act at the interface between development and secondary metabolism. The CSN is a multi-protein complex of up to eight subunits and controls the activation of CULLIN-RING E3 ubiquitin ligases, which mark substrates with ubiquitin chains for protein degradation by the proteasome. The nuclear velvet complex consists of the velvet-domain proteins VeA and VelB and the putative methyltransferase LaeA acting as a global regulator for secondary metabolism. Defects in both complexes disturb fungal development, light perception, and the control of secondary metabolism. The potential biotechnological relevance of these developmental fungal mutant strains for drug discovery, agriculture, food safety, and human healthcare is discussed.
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Affiliation(s)
- Jennifer Gerke
- Institut für Mikrobiologie & Genetik, Georg-August-Universität, Grisebachstr. 8, D-37077 Göttingen, Germany
| | - Gerhard H. Braus
- Institut für Mikrobiologie & Genetik, Georg-August-Universität, Grisebachstr. 8, D-37077 Göttingen, Germany
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Morisaki A, Yamada N, Yamanaka S, Matsui K. Dimethyl sulfide as a source of the seaweed-like aroma in cooked soybeans and correlation with its precursor, S-methylmethionine (vitamin U). JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2014; 62:8289-94. [PMID: 25090616 DOI: 10.1021/jf501614j] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Among the soybean germplasm in Japan, two varieties, Nishiyamahitashi 98-5 (NH) and Shinanokurakake (SKK), have an intense seaweed-like flavor after cooking. Gas-liquid chromatography with mass spectrometry (GC-MS) indicated that a significant amount (11.5 ± 3.46 μg g(-1) for NH and 6.66 ± 0.91 μg g(-1) for SKK) of dimethyl sulfide (DMS) was formed after heat treatment. DMS is formed from S-methylmethionine (SMM, vitamin U). SMM was detected in all soybean varieties examined here, but its concentration in NH and SKK seeds was >100-fold higher than in the other varieties and ranged from 75 to 290 μg g(-1). The SMM content and the ability to form DMS upon heat treatment correlated among them. The plumes and radicles contained SMM exclusively. This is the first report of soybean varieties containing SMM at a level equivalent to or higher than that in vegetables known to contain high levels of SMM, for example, turnip, cabbage, and celery.
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Affiliation(s)
- Akira Morisaki
- Graduate School of Medicine (Agriculture) and Department of Biological Chemistry, Faculty of Agriculture, Yamaguchi University , Yamaguchi 753-8515, Japan
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Sarikaya-Bayram O, Bayram O, Feussner K, Kim JH, Kim HS, Kaever A, Feussner I, Chae KS, Han DM, Han KH, Braus GH. Membrane-bound methyltransferase complex VapA-VipC-VapB guides epigenetic control of fungal development. Dev Cell 2014; 29:406-20. [PMID: 24871947 DOI: 10.1016/j.devcel.2014.03.020] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2013] [Revised: 02/26/2014] [Accepted: 03/25/2014] [Indexed: 12/16/2022]
Abstract
Epigenetic and transcriptional control of gene expression must be coordinated in response to external signals to promote alternative multicellular developmental programs. The membrane-associated trimeric complex VapA-VipC-VapB controls a signal transduction pathway for fungal differentiation. The VipC-VapB methyltransferases are tethered to the membrane by the FYVE-like zinc finger protein VapA, allowing the nuclear VelB-VeA-LaeA complex to activate transcription for sexual development. Once the release from VapA is triggered, VipC-VapB is transported into the nucleus. VipC-VapB physically interacts with VeA and reduces its nuclear import and protein stability, thereby reducing the nuclear VelB-VeA-LaeA complex. Nuclear VapB methyltransferase diminishes the establishment of facultative heterochromatin by decreasing histone 3 lysine 9 trimethylation (H3K9me3). This favors activation of the regulatory genes brlA and abaA, which promote the asexual program. The VapA-VipC-VapB methyltransferase pathway combines control of nuclear import and stability of transcription factors with histone modification to foster appropriate differentiation responses.
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Affiliation(s)
- Ozlem Sarikaya-Bayram
- Department of Molecular Microbiology and Genetics, Georg August University, Grisebachstrasse 8, Göttingen 37077, Germany
| | - Ozgür Bayram
- Department of Molecular Microbiology and Genetics, Georg August University, Grisebachstrasse 8, Göttingen 37077, Germany
| | - Kirstin Feussner
- Department of Plant Biochemistry, Georg August University, Justus-von-Liebig-Weg 11, Göttingen 37077, Germany
| | - Jong-Hwa Kim
- Department of Pharmaceutical Engineering, Woosuk University, Wanju 565-701, Korea
| | - Hee-Seo Kim
- Department of Pharmaceutical Engineering, Woosuk University, Wanju 565-701, Korea; Department of Molecular Biology, Chonbuk National University, Jeonju 561-756, Korea
| | - Alexander Kaever
- Department of Bioinformatics, Georg August University, Goldschmidtstrasse 1, Göttingen 37077, Germany
| | - Ivo Feussner
- Department of Plant Biochemistry, Georg August University, Justus-von-Liebig-Weg 11, Göttingen 37077, Germany
| | - Keon-Sang Chae
- Department of Molecular Biology, Chonbuk National University, Jeonju 561-756, Korea
| | - Dong-Min Han
- Division of Life Sciences, Wonkwang University, Iksan 570-749, Korea
| | - Kap-Hoon Han
- Department of Pharmaceutical Engineering, Woosuk University, Wanju 565-701, Korea
| | - Gerhard H Braus
- Department of Molecular Microbiology and Genetics, Georg August University, Grisebachstrasse 8, Göttingen 37077, Germany.
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Fekete E, Karaffa L, Karimi Aghcheh R, Németh Z, Fekete E, Orosz A, Paholcsek M, Stágel A, Kubicek CP. The transcriptome of lae1 mutants of Trichoderma reesei cultivated at constant growth rates reveals new targets of LAE1 function. BMC Genomics 2014; 15:447. [PMID: 24909838 PMCID: PMC4061448 DOI: 10.1186/1471-2164-15-447] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Accepted: 06/04/2014] [Indexed: 01/02/2023] Open
Abstract
Background The putative methyltransferase LaeA is a global regulator that affects the expression of multiple secondary metabolite gene clusters in several fungi. In Trichoderma reesei, its ortholog LAE1 appears to predominantly regulate genes involved in increasing competitive fitness in its environment, including expression of cellulases and polysaccharide hydrolases. A drawback in all studies related to LaeA/LAE1 function so far, however, is that the respective loss-of-function and overexpressing mutants display different growth rates. Thus some of the properties attributed to LaeA/LAE1 could be simply due to changes of the growth rate. Results We cultivated T. reesei, a Δlae1 mutant and a lae1-overexpressing strain in chemostats on glucose at two different growth rates (0.075 and 0.020 h-1) which resemble growth rates at repressing and derepressing conditions, respectively. Under these conditions, the effect of modulating LAE1 expression was mainly visible in the Δlae1 mutant, whereas the overexpressing strain showed little differences to the parent strain. The effect on the expression of some gene categories identified earlier (polyketide synthases, heterokaryon incompatibility proteins, PTH11-receptors) was confirmed, but in addition GCN5-N-acetyltransferases, amino acid permeases and flavin monooxygenases were identified as so far unknown major targets of LAE1 action. LAE1 was also shown to interfere with the regulation of expression of several genes by the growth rate. About a tenth of the genes differentially expressed in the Δlae1 mutant under either growth condition were found to be clustered in the genome, but no specific gene group was associated with this phenomenon. Conclusions Our data show that – using T. reesei LAE1 as a model - the investigation of transcriptome in regulatory mutants at constant growth rates leads to new insights into the physiological roles of the respective regulator. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-447) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | - Levente Karaffa
- Department of Biochemical Engineering, Faculty of Science and Technology, University of Debrecen, Egyetem tér 1, H-4032 Debrecen, Hungary.
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Strategies for mining fungal natural products. J Ind Microbiol Biotechnol 2013; 41:301-13. [PMID: 24146366 DOI: 10.1007/s10295-013-1366-3] [Citation(s) in RCA: 133] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Accepted: 10/05/2013] [Indexed: 10/26/2022]
Abstract
Fungi are well known for their ability to produce a multitude of natural products. On the one hand their potential to provide beneficial antibiotics and immunosuppressants has been maximized by the pharmaceutical industry to service the market with cost-efficient drugs. On the other hand identification of trace amounts of known mycotoxins in food and feed samples is of major importance to ensure consumer health and safety. Although several fungal natural products, their biosynthesis and regulation are known today, recent genome sequences of hundreds of fungal species illustrate that the secondary metabolite potential of fungi has been substantially underestimated. Since expression of genes and subsequent production of the encoded metabolites are frequently cryptic or silent under standard laboratory conditions, strategies for activating these hidden new compounds are essential. This review will cover the latest advances in fungal genome mining undertaken to unlock novel products.
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