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Nagappan J, Ooi SE, Chan KL, Kadri F, Nurazah Z, Halim MAA, Angel LPL, Sundram S, Chin CF, May ST, Low ETL. Transcriptional effects of carbon and nitrogen starvation on Ganoderma boninense, an oil palm phytopathogen. Mol Biol Rep 2024; 51:212. [PMID: 38273212 DOI: 10.1007/s11033-023-09054-4] [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: 05/22/2023] [Accepted: 10/24/2023] [Indexed: 01/27/2024]
Abstract
BACKGROUND Ganoderma boninense is a phytopathogen of oil palm, causing basal and upper stem rot diseases. METHODS The genome sequence was used as a reference to study gene expression during growth in a starved carbon (C) and nitrogen (N) environment with minimal sugar and sawdust as initial energy sources. This study was conducted to mimic possible limitations of the C-N nutrient sources during the growth of G. boninense in oil palm plantations. RESULTS Genome sequencing of an isolate collected from a palm tree in West Malaysia generated an assembly of 67.12 Mb encoding 19,851 predicted genes. Transcriptomic analysis from a time course experiment during growth in this starvation media identified differentially expressed genes (DEGs) that were found to be associated with 29 metabolic pathways. During the active growth phase, 26 DEGs were related to four pathways, including secondary metabolite biosynthesis, carbohydrate metabolism, glycan metabolism and mycotoxin biosynthesis. G. boninense genes involved in the carbohydrate metabolism pathway that contribute to the degradation of plant cell walls were up-regulated. Interestingly, several genes associated with the mycotoxin biosynthesis pathway were identified as playing a possible role in pathogen-host interaction. In addition, metabolomics analysis revealed six metabolites, maltose, xylobiose, glucooligosaccharide, glycylproline, dimethylfumaric acid and arabitol that were up-regulated on Day2 of the time course experiment. CONCLUSIONS This study provides information on genes expressed by G. boninense in metabolic pathways that may play a role in the initial infection of the host.
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Affiliation(s)
- Jayanthi Nagappan
- Malaysian Palm Oil Board, 6, Persiaran Institusi, Bandar Baru Bangi, 43000, Kajang, Selangor, Malaysia
- School of Biosciences, University of Nottingham Malaysia, Jalan Broga, 43500, Semenyih, Selangor, Malaysia
| | - Siew-Eng Ooi
- Malaysian Palm Oil Board, 6, Persiaran Institusi, Bandar Baru Bangi, 43000, Kajang, Selangor, Malaysia
| | - Kuang-Lim Chan
- Malaysian Palm Oil Board, 6, Persiaran Institusi, Bandar Baru Bangi, 43000, Kajang, Selangor, Malaysia
| | - Faizun Kadri
- Malaysian Palm Oil Board, 6, Persiaran Institusi, Bandar Baru Bangi, 43000, Kajang, Selangor, Malaysia
| | - Zain Nurazah
- Malaysian Palm Oil Board, 6, Persiaran Institusi, Bandar Baru Bangi, 43000, Kajang, Selangor, Malaysia
| | - Mohd Amin Ab Halim
- Malaysian Palm Oil Board, 6, Persiaran Institusi, Bandar Baru Bangi, 43000, Kajang, Selangor, Malaysia
| | - Lee Pei Lee Angel
- Malaysian Palm Oil Board, 6, Persiaran Institusi, Bandar Baru Bangi, 43000, Kajang, Selangor, Malaysia
| | - Shamala Sundram
- Malaysian Palm Oil Board, 6, Persiaran Institusi, Bandar Baru Bangi, 43000, Kajang, Selangor, Malaysia
| | - Chiew-Foan Chin
- School of Biosciences, University of Nottingham Malaysia, Jalan Broga, 43500, Semenyih, Selangor, Malaysia
| | - Sean T May
- School of Biosciences, University of Nottingham, Sutton Bonington Campus, Nr Loughborough, LE12 5RD, UK
| | - Eng Ti Leslie Low
- Malaysian Palm Oil Board, 6, Persiaran Institusi, Bandar Baru Bangi, 43000, Kajang, Selangor, Malaysia.
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Yang C, Wu D, Lin H, Ma D, Fu W, Yao Y, Pan X, Wang S, Zhuang Z. Role of RNA Modifications, Especially m6A, in Aflatoxin Biosynthesis of Aspergillus flavus. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:726-741. [PMID: 38112282 DOI: 10.1021/acs.jafc.3c05926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
RNA modifications play key roles in eukaryotes, but the functions in Aspergillus flavus are still unknown. Temperature has been reported previously to be a critical environmental factor that regulates the aflatoxin production of A. flavus, but much remains to be learned about the molecular networks. Here, we demonstrated that 12 kinds of RNA modifications in A. flavus were significantly changed under 29 °C compared to 37 °C incubation; among them, m6A was further verified by a colorimetric method. Then, the transcriptome-wide m6A methylome and m6A-altered genes were comprehensively illuminated through methylated RNA immunoprecipitation sequencing and RNA sequencing, from which 22 differentially methylated and expressed transcripts under 29 °C were screened out. It is especially notable that AFCA_009549, an aflatoxin biosynthetic pathway gene (aflQ), and the m6A methylation of its 332nd adenine in the mRNA significantly affect aflatoxin biosynthesis in A. flavus both on media and crop kernels. The content of sterigmatocystin in both ΔaflQ and aflQA332C strains was significantly higher than that in the WT strain. Together, these findings reveal that RNA modifications are associated with secondary metabolite biosynthesis of A. flavus.
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Affiliation(s)
- Chi Yang
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, Proteomic Research Center, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Institute of Edible Mushroom, Fujian Academy of Agricultural Sciences, Fuzhou 350012, China
| | - Dandan Wu
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, Proteomic Research Center, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Hong Lin
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, Proteomic Research Center, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Dongmei Ma
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, Proteomic Research Center, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- College of Animal Sciences (College of Bee Science), Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Wangzhuo Fu
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, Proteomic Research Center, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Yanfang Yao
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, Proteomic Research Center, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Xiaohua Pan
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, Proteomic Research Center, 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, Proteomic Research Center, 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, Proteomic Research Center, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China
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Davati N, Ghorbani A. Discovery of long non-coding RNAs in Aspergillus flavus response to water activity, CO 2 concentration, and temperature changes. Sci Rep 2023; 13:10330. [PMID: 37365206 DOI: 10.1038/s41598-023-37236-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 06/19/2023] [Indexed: 06/28/2023] Open
Abstract
Although the role of long non-coding RNAs (lncRNAs) in key biological processes in animals and plants has been confirmed for decades, their identification in fungi remains limited. In this study, we discovered and characterized lncRNAs in Aspergillus flavus in response to changes in water activity, CO2 concentration, and temperature, and predicted their regulatory roles in cellular functions. A total of 472 lncRNAs were identified in the genome of A. flavus, consisting of 470 novel lncRNAs and 2 putative lncRNAs (EFT00053849670 and EFT00053849665). Our analysis of lncRNA expression revealed significant differential expression under stress conditions in A. flavus. Our findings indicate that lncRNAs in A. flavus, particularly down-regulated lncRNAs, may play pivotal regulatory roles in aflatoxin biosynthesis, respiratory activities, cellular survival, and metabolic maintenance under stress conditions. Additionally, we predicted that sense lncRNAs down-regulated by a temperature of 30 °C, osmotic stress, and CO2 concentration might indirectly regulate proline metabolism. Furthermore, subcellular localization analysis revealed that up-and down-regulated lncRNAs are frequently localized in the nucleus under stress conditions, particularly at a water activity of 0.91, while most up-regulated lncRNAs may be located in the cytoplasm under high CO2 concentration.
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Affiliation(s)
- Nafiseh Davati
- Department of Food Science and Technology, College of Food Industry, Bu-Ali Sina University, Hamedan, 65167-38695, Iran.
| | - Abozar Ghorbani
- Nuclear Agriculture Research School, Nuclear Science and Technology Research Institute (NSTRI), Karaj, Iran.
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Wu S, Huang W, Wang F, Zou X, Li X, Liu CM, Zhang W, Yan S. Integrated metabolomics and lipidomics analyses suggest the temperature-dependent lipid desaturation promotes aflatoxin biosynthesis in Aspergillus flavus. Front Microbiol 2023; 14:1137643. [PMID: 37065116 PMCID: PMC10102665 DOI: 10.3389/fmicb.2023.1137643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Accepted: 03/17/2023] [Indexed: 04/03/2023] Open
Abstract
Temperature is one of the main factors affecting aflatoxin (AF) biosynthesis in Aspergillus flavus. Previous studies showed that AF biosynthesis is elevated in A. flavus at temperatures between 28°C-30°C, while it is inhibited at temperatures above 30°C. However, little is known about the metabolic mechanism underlying temperature-regulated AF biosynthesis. In this study, we integrated metabolomic and lipidomic analyses to investigate the endogenous metabolism of A. flavus across 6 days of mycelia growth at 28°C (optimal AF production) and 37°C (no AF production). Results showed that both metabolite and lipid profiles were significantly altered at different temperatures. In particular, metabolites involved in carbohydrate and amino acid metabolism were up-regulated at 37°C on the second day but down-regulated from days three to six. Moreover, lipidomics and targeted fatty acids analyses of mycelia samples revealed a distinct pattern of lipid species and free fatty acids desaturation. High degrees of polyunsaturation of most lipid species at 28°C were positively correlated with AF production. These results provide new insights into the underlying metabolic changes in A. flavus under temperature stress.
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Affiliation(s)
- Shaowen Wu
- Guangdong Key Laboratory for Crop Germplasm Resources Preservation and Utilization, Agro-biological Gene Research Center, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Wenjie Huang
- Guangdong Key Laboratory for Crop Germplasm Resources Preservation and Utilization, Agro-biological Gene Research Center, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Fenghua Wang
- Guangdong Key Laboratory for Crop Germplasm Resources Preservation and Utilization, Agro-biological Gene Research Center, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Xinlu Zou
- Guangdong Key Laboratory for Crop Germplasm Resources Preservation and Utilization, Agro-biological Gene Research Center, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Xuan Li
- Guangdong Key Laboratory for Crop Germplasm Resources Preservation and Utilization, Agro-biological Gene Research Center, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Chun-Ming Liu
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Wenyang Zhang
- Guangdong Key Laboratory for Crop Germplasm Resources Preservation and Utilization, Agro-biological Gene Research Center, Guangdong Academy of Agricultural Sciences, Guangzhou, China
| | - Shijuan Yan
- Guangdong Key Laboratory for Crop Germplasm Resources Preservation and Utilization, Agro-biological Gene Research Center, Guangdong Academy of Agricultural Sciences, Guangzhou, China
- *Correspondence: Shijuan Yan,
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Ferrara M, Perrone G, Gallo A. Recent advances in biosynthesis and regulatory mechanisms of principal mycotoxins. Curr Opin Food Sci 2022. [DOI: 10.1016/j.cofs.2022.100923] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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6
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Wen Y, Liao B, Yan X, Wu Z, Tian X. Temperature-responsive regulation of the fermentation of hypocrellin A by Shiraia bambusicola (GDMCC 60438). Microb Cell Fact 2022; 21:135. [PMID: 35787717 PMCID: PMC9254528 DOI: 10.1186/s12934-022-01862-w] [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: 02/08/2022] [Accepted: 06/24/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Hypocrellin A (HA) is a perylene quinone pigment with high medicinal value that is produced by Shiraia bambusicola Henn. (S. bambusicola) and Hypocrella bambusae (Berk. & Broome) Sacc. (Ascomycetes) with great potential in clinical photodynamic therapy. Submerged cultivation of S. bambusicola is a popular technique for HA production. However, there is not much research on how temperature changes lead to differential yields of HA production. RESULTS The temperature regulation of submerged fermentation is an efficient approach to promote HA productivity. After a 32 °C fermentation, the HA content in the mycelia S. bambusicola (GDMCC 60438) was increased by more than three- and fivefold when compared to that at 28 °C and 26 °C, respectively. RNA sequencing (RNA-seq) analysis showed that the regulation of the expression of transcription factors and genes essential for HA biosynthesis could be induced by high temperature. Among the 496 differentially expressed genes (DEGs) explicitly expressed at 32 °C, the hub genes MH01c06g0046321 and MH01c11g0073001 in the coexpression network may affect HA biosynthesis and cytoarchitecture, respectively. Moreover, five genes, i.e., MH01c01g0006641, MH01c03g0017691, MH01c04g0029531, MH01c04g0030701 and MH01c22g0111101, potentially related to HA synthesis also exhibited significantly higher expression levels. Morphological observation showed that the autolysis inside the mycelial pellets tightly composted intertwined mycelia without apparent holes. CONCLUSIONS The obtained results provide an effective strategy in the submerged fermentation of S. bambusicola for improved HA production and reveal an alternative regulatory network responsive to the biosynthesis metabolism of HA in response to environmental signals.
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Affiliation(s)
- Yongdi Wen
- Guangdong Key Laboratory of Fermentation & Enzyme Engineering, School of Biology and Biological Engineering, South China University of Technology, 382 East Out Loop, University Park, Guangzhou, 510006, China
| | - Baosheng Liao
- The Second Clinical College, Guangzhou University of Chinese Medicine, 232 East Out Loop, University Park, Guangzhou, 510006, China
| | - Xiaoxiao Yan
- Zhuhai Institute of Modern Industrial Innovation, South China University of Technology, 8 Fushan Road, Fushan Industrial Park, Zhuhai, 519100, China
| | - Zhenqiang Wu
- Guangdong Key Laboratory of Fermentation & Enzyme Engineering, School of Biology and Biological Engineering, South China University of Technology, 382 East Out Loop, University Park, Guangzhou, 510006, China
| | - Xiaofei Tian
- Guangdong Key Laboratory of Fermentation & Enzyme Engineering, School of Biology and Biological Engineering, South China University of Technology, 382 East Out Loop, University Park, Guangzhou, 510006, China. .,Zhuhai Institute of Modern Industrial Innovation, South China University of Technology, 8 Fushan Road, Fushan Industrial Park, Zhuhai, 519100, China.
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Gallo A, Perrone G. Current Approaches for Advancement in Understanding the Molecular Mechanisms of Mycotoxin Biosynthesis. Int J Mol Sci 2021; 22:ijms22157878. [PMID: 34360643 PMCID: PMC8346063 DOI: 10.3390/ijms22157878] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 07/20/2021] [Accepted: 07/21/2021] [Indexed: 12/17/2022] Open
Abstract
Filamentous fungi are able to synthesise a remarkable range of secondary metabolites, which play various key roles in the interaction between fungi and the rest of the biosphere, determining their ecological fitness. Many of them can have a beneficial activity to be exploited, as well as negative impact on human and animal health, as in the case of mycotoxins contaminating large quantities of food, feed, and agricultural products worldwide and posing serious health and economic risks. The elucidation of the molecular aspects of mycotoxin biosynthesis has been greatly sped up over the past decade due to the advent of next-generation sequencing technologies, which greatly reduced the cost of genome sequencing and related omic analyses. Here, we briefly highlight the recent progress in the use and integration of omic approaches for the study of mycotoxins biosynthesis. Particular attention has been paid to genomics and transcriptomic approaches for the identification and characterisation of biosynthetic gene clusters of mycotoxins and the understanding of the regulatory pathways activated in response to physiological and environmental factors leading to their production. The latest innovations in genome-editing technology have also provided a more powerful tool for the complete explanation of regulatory and biosynthesis pathways. Finally, we address the crucial issue of the interpretation of the combined omics data on the biology of the mycotoxigenic fungi. They are rapidly expanding and require the development of resources for more efficient integration, as well as the completeness and the availability of intertwined data for the research community.
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Affiliation(s)
- Antonia Gallo
- Institute of Sciences of Food Production (ISPA) National Research Council (CNR), 73100 Lecce, Italy
- Correspondence: (A.G.); (G.P.)
| | - Giancarlo Perrone
- Institute of Sciences of Food Production (ISPA) National Research Council (CNR), 70126 Bari, Italy
- Correspondence: (A.G.); (G.P.)
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Gao J, Xu X, Huang K, Liang Z. Fungal G-Protein-Coupled Receptors: A Promising Mediator of the Impact of Extracellular Signals on Biosynthesis of Ochratoxin A. Front Microbiol 2021; 12:631392. [PMID: 33643259 PMCID: PMC7907439 DOI: 10.3389/fmicb.2021.631392] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Accepted: 01/21/2021] [Indexed: 01/17/2023] Open
Abstract
G-protein-coupled receptors (GPCRs) are transmembrane receptors involved in transducing signals from the external environment inside the cell, which enables fungi to coordinate cell transport, metabolism, and growth to promote their survival, reproduction, and virulence. There are 14 classes of GPCRs in fungi involved in sensing various ligands. In this paper, the synthesis of mycotoxins that are GPCR-mediated is discussed with respect to ligands, environmental stimuli, and intra-/interspecific communication. Despite their apparent importance in fungal biology, very little is known about the role of ochratoxin A (OTA) biosynthesis by Aspergillus ochraceus and the ligands that are involved. Fortunately, increasing evidence shows that the GPCR that involves the AF/ST (sterigmatocystin) pathway in fungi belongs to the same genus. Therefore, we speculate that GPCRs play an important role in a variety of environmental signals and downstream pathways in OTA biosynthesis. The verification of this inference will result in a more controllable GPCR target for control of fungal contamination in the future.
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Affiliation(s)
- Jing Gao
- Beijing Laboratory for Food Quality and Safety, Beijing, China
| | - Xinge Xu
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China
| | - Kunlun Huang
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China
| | - Zhihong Liang
- Beijing Laboratory for Food Quality and Safety, Beijing, China.,College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China
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A Novel Site-Specific Integration System for Genetic Modification of Aspergillus flavus. G3-GENES GENOMES GENETICS 2020; 10:605-611. [PMID: 31818874 PMCID: PMC7003095 DOI: 10.1534/g3.119.400699] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Aspergillus flavus is a fungus that produces aflatoxin B1, one of the most carcinogenic secondary metabolites. Understanding the regulation mechanism of aflatoxin biosynthesis in this fungus requires precise methods for genomic integration of mutant alleles. To avoid the disadvantage of DNA integration into the genome by non-homologous or ectopic recombination, we developed a novel strategy for site-specific integration of foreign DNA by using a carboxin-resistant sdh2R allele (His 249 Leu). Our results demonstrated that the transformants were generated with a high efficiency (>96%) of correct integration into the sdh2-lcus of the genome of A. flavus NRRL 3357. The advantage of this method is that introduction of the eGFP expression cassette into the sdh2-locus had little effect on fungal growth and virulence while also being rapid and efficient. This system will be a valuable tool for genetic manipulation in A. flavus. To the best of our knowledge, this is the first report on the efficient site-specific integration at the sdh2-locus in the genome of Aspergillus.
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10
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Han G, Zhao K, Yan X, Xiang F, Li X, Tao F. Differential regulation of mycelial growth and aflatoxin biosynthesis by Aspergillus flavus under different temperatures as revealed by strand-specific RNA-Seq. Microbiologyopen 2019; 8:e897. [PMID: 31328901 PMCID: PMC6813451 DOI: 10.1002/mbo3.897] [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: 12/17/2018] [Revised: 06/06/2019] [Accepted: 06/10/2019] [Indexed: 11/11/2022] Open
Abstract
Although several regulatory pathways have been reported for Aspergillus flavus, the regulation of aflatoxin production and mycelial growth under different temperatures remains unclear. In this study, A. flavus differentially expressed genes (DEGs) and regulatory pathways were analyzed under three temperatures, by strand‐specific RNA‐Seq. Results show that a total of 2,428 and 1,474 DEGs were identified in fungal mycelia cultured at 20°C and 37°C, respectively, as compared with the control (28°C). Approximately ~ 79% of DEGs in the 37°C samples were up‐regulated genes, while ~ 63% of DEGs in the 20°C samples were down‐regulated genes. Most of the DEG pathways enriched by lower temperatures differed from those enriched by higher temperatures, while only a small portion of the pathways were shared by A. flavus grown under different temperatures. Aflatoxin biosynthesis, Butanoate metabolism, oxidation–reduction process, and benzene‐containing compound metabolic process were the shared down‐regulated pathways, while steroid biosynthesis, oxidoreductase activity, cellular protein modification process, DNA binding, protein complex were the shared up‐regulated pathways between lower and higher temperatures. The shared genes and pathways are the key regulatory candidates for aflatoxin biosynthesis with changes of temperature. In addition, the identification of both up‐regulated and down‐regulated genes provides a useful gene set for further investigation of the aflatoxin biosynthesis among Aspergillus.
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Affiliation(s)
- Guomin Han
- School of Life Sciences, Anhui Agricultural University, Hefei, China.,The National Engineering Laboratory of Crop Stress Resistance Breeding, Anhui Agricultural University, Hefei, China
| | - Kai Zhao
- School of Life Sciences, Anhui Agricultural University, Hefei, China
| | - Xiaodan Yan
- School of Management, Hefei University of Technology, Hefei, China
| | - Fangzhi Xiang
- School of Life Sciences, Anhui Agricultural University, Hefei, China
| | - Xuede Li
- School of Resources and Environment, Anhui Agricultural University, Hefei, China
| | - Fang Tao
- School of Life Sciences, Anhui Agricultural University, Hefei, China
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