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Qiu C, Liu Z. Positive selection and functional diversification of transcription factor Cmr1 homologs in Alternaria. Appl Microbiol Biotechnol 2024; 108:133. [PMID: 38229332 DOI: 10.1007/s00253-023-12893-7] [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: 06/30/2023] [Revised: 12/04/2023] [Accepted: 12/07/2023] [Indexed: 01/18/2024]
Abstract
Transcription factor Cmr1 (Colletotrichum melanin regulation 1) and its homologs in several plant fungal pathogens are the regulators of the 1,8-dihydroxynaphthalene (DHN)-melanin biosynthesis pathway and have evolved functional diversification in morphology and pathogenicity. The fungal genus Alternaria comprises the group of "black fungi" that are rich in DHN-melanin in the primary cell wall and septa of the conidia. Some Alternaria species cause many economically important plant diseases worldwide. However, the evolution and function of Cmr1 homologs in Alternaria remain poorly understood. Here, we identified a total of forty-two Cmr1 homologs from forty-two Alternaria spp. and all contained one additional diverse fungal specific transcription factor motif. Phylogenetic analysis indicated the division of these homologs into five major clades and three branches. Dated phylogeny showed the A and D clades diverged latest and earliest, respectively. Molecular evolutionary analyses revealed that three amino acid sites of Cmr1 homologs in Alternaria were the targets of positive selection. Asmr1, the homolog of Cmr1 in the potato early blight pathogen, Alternaria solani was amplified and displayed the sequence conservation at the amino acid level in different A. solani isolates. Asmr1 was further confirmed to have the transcriptional activation activity and was upregulated during the early stage of potato infection. Deletion of asmr1 led to the decreased melanin content and pathogenicity, deformed conidial morphology, and responses to cell wall and fungicide stresses in A. solani. These results suggest positive selection and functional divergence have played a role in the evolution of Cmr1 homologs in Alternaria. KEY POINTS: • Cmr1 homologs were under positive selection in Alternaria species • Asmr1 is a functional transcription factor, involved in spore development, melanin biosynthesis, pathogenicity, and responses to cell wall and fungicide stresses in A. solani • Cmr1 might be used as a potential taxonomic marker of the genus Alternaria.
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Affiliation(s)
- Chaodong Qiu
- Department of Plant Pathology, School of Plant Protection, Anhui Agricultural University, Hefei, Anhui, 230036, China
| | - Zhenyu Liu
- Department of Plant Pathology, School of Plant Protection, Anhui Agricultural University, Hefei, Anhui, 230036, China.
- Anhui Province Key Laboratory of Integrated Pest Management On Crops, Hefei, Anhui, 230036, China.
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2
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Catanzaro I, Gerrits R, Feldmann I, Gorbushina AA, Onofri S, Schumacher J. Deletion of the polyketide synthase-encoding gene pks1 prevents melanization in the extremophilic fungus Cryomyces antarcticus. IUBMB Life 2024. [PMID: 39011777 DOI: 10.1002/iub.2895] [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: 02/05/2024] [Accepted: 05/15/2024] [Indexed: 07/17/2024]
Abstract
Cryomyces antarcticus, a melanized cryptoendolithic fungus endemic to Antarctica, can tolerate environmental conditions as severe as those in space. Particularly, its ability to withstand ionizing radiation has been attributed to the presence of thick and highly melanized cell walls, which-according to a previous investigation-may contain both 1,8-dihydroxynaphthalene (DHN) and L-3,4 dihydroxyphenylalanine (L-DOPA) melanin. The genes putatively involved in the synthesis of DHN melanin were identified in the genome of C. antarcticus. Most important is capks1 encoding a non-reducing polyketide synthase (PKS) and being the ortholog of the functionally characterized kppks1 from the rock-inhabiting fungus Knufia petricola. The co-expression of CaPKS1 or KpPKS1 with a 4'-phosphopantetheinyl transferase in Saccharomyces cerevisiae resulted in the formation of a yellowish pigment, suggesting that CaPKS1 is the enzyme providing the precursor for DHN melanin. To dissect the composition and function of the melanin layer in the outer cell wall of C. antarcticus, non-melanized mutants were generated by CRISPR/Cas9-mediated genome editing. Notwithstanding its slow growth (up to months), three independent non-melanized Δcapks1 mutants were obtained. The mutants exhibited growth similar to the wild type and a light pinkish pigmentation, which is presumably due to carotenoids. Interestingly, visible light had an adverse effect on growth of both melanized wild-type and non-melanized Δcapks1 strains. Further evidence that light can pass the melanized cell walls derives from a mutant expressing a H2B-GFP fusion protein, which can be detected by fluorescence microscopy. In conclusion, the study reports on the first genetic manipulation of C. antarcticus, resulting in non-melanized mutants and demonstrating that the melanin is rather of the DHN type. These mutants will allow to elucidate the relevance of melanization for surviving extreme conditions found in the natural habitat as well as in space.
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Affiliation(s)
- Ilaria Catanzaro
- Department Materials and the Environment, Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany
- Department of Ecological and Biological Sciences (DEB), Università degli Studi della Tuscia, Viterbo, Italy
| | - Ruben Gerrits
- Department Materials and the Environment, Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany
| | - Ines Feldmann
- Department Materials and the Environment, Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany
| | - Anna A Gorbushina
- Department Materials and the Environment, Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany
- Department of Biology, Chemistry, Pharmacy, Freie Universität Berlin, Berlin, Germany
| | - Silvano Onofri
- Department of Ecological and Biological Sciences (DEB), Università degli Studi della Tuscia, Viterbo, Italy
| | - Julia Schumacher
- Department Materials and the Environment, Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany
- Department of Biology, Chemistry, Pharmacy, Freie Universität Berlin, Berlin, Germany
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3
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Li R, Li Y, Xu W, Liu W, Xu X, Bi Y, Prusky D. Aabrm1-mediated melanin synthesis is essential to growth and development, stress adaption, and pathogenicity in Alternaria alternata. Front Microbiol 2024; 14:1327765. [PMID: 38274752 PMCID: PMC10808324 DOI: 10.3389/fmicb.2023.1327765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 12/22/2023] [Indexed: 01/27/2024] Open
Abstract
Scytalone dehydratase (brm1) is one of the key enzymes in 1, 8-dihydroxynaphthalene (DHN) melanin synthesis, which mediates melanin biosythesis and regulates cell biological process of plant fungi, but its function in Alternaria alternata, the causal agent of pear black spot, is unclear. Brm1 in A. alternata was cloned, identified, and named as Aabrm1. An Aabrm1-deletion mutant was generated and revealed that the deletion of Aabrm1 leads to a significant decrease in melanin production and forms orange colony smooth spores. In addition, the deletion of Aabrm1 gene impaired infection structure information and penetration. The external stress resistance of ΔAabrm1 was significantly weakened, and, in particular, it is very sensitive to oxidative stress, and the contents of H2O2 and O2.- in ΔAabrm1 were significantly increased. Virulence of ΔAabrm1 was reduced in non-wound-inoculated pear leaves but not changed in wound-inoculated pear fruit. These results indicated that Aabrm1-mediated melanin synthesis plays an important role in the pathogenicity of A. alternata.
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Affiliation(s)
- Rong Li
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, China
| | - Yongcai Li
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, China
| | - Wenyi Xu
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, China
| | - Wenjuan Liu
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, China
| | - Xiaobin Xu
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, China
| | - Yang Bi
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, China
| | - Dov Prusky
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, China
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization, Bet Dagan, Israel
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Yuan Z, Li Y, He Y, Qian K, Zhang Y. Differential Analysis of Three Copper-Based Nanomaterials with Different Morphologies to Suppress Alternaria alternata and Safety Evaluation. Int J Mol Sci 2023; 24:ijms24119673. [PMID: 37298626 DOI: 10.3390/ijms24119673] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 05/21/2023] [Accepted: 05/23/2023] [Indexed: 06/12/2023] Open
Abstract
The overuse of copper-based fertilizers and pesticides over the last few decades has resulted in detrimental risks to our environment. Nano-enabled agrichemicals with a high effective utilization ratio have shown great potential for maintaining or minimizing environmental issues in agriculture. Copper-based nanomaterials (Cu-based NMs) serve as a promising alternative to fungicides. Three types of Cu-based NMs with different morphologies were analyzed for their different antifungal effects on Alternaria alternata in this current study. Compared to commercial copper hydroxide water power (Cu(OH)2 WP), all tested Cu-based NMs, including cuprous oxide nanoparticles (Cu2O NPs), copper nanorods (Cu NRs) and copper nanowires (Cu NWs), especially Cu2O NPs and Cu NWs, showed higher antifungal activity against Alternaria alternata. Its EC50 were 104.24 and 89.40 mg L-1, respectively, achieving comparable activity using a dose approximately 1.6 and 1.9-fold lower. Cu-based NMs could introduce the downregulation of melanin production and soluble protein content. In contrast to trends in antifungal activity, Cu2O NPs showed the strongest power in regulating melanin production and protein content and similarly exhibited the highest acute toxicity to adult zebrafish compared to other Cu-based NMs. These results demonstrate that Cu-based NMs could offer great potential in plant disease management strategies.
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Affiliation(s)
- Zitong Yuan
- College of Plant Protection, Southwest University, Chongqing 400715, China
| | - Yiwei Li
- College of Plant Protection, Southwest University, Chongqing 400715, China
| | - Yuke He
- College of Plant Protection, Southwest University, Chongqing 400715, China
| | - Kun Qian
- College of Plant Protection, Southwest University, Chongqing 400715, China
| | - Yongqiang Zhang
- College of Plant Protection, Southwest University, Chongqing 400715, China
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Guegan H, Poirier W, Ravenel K, Dion S, Delabarre A, Desvillechabrol D, Pinson X, Sergent O, Gallais I, Gangneux JP, Giraud S, Gastebois A. Deciphering the Role of PIG1 and DHN-Melanin in Scedosporium apiospermum Conidia. J Fungi (Basel) 2023; 9:jof9020134. [PMID: 36836250 PMCID: PMC9965090 DOI: 10.3390/jof9020134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 01/10/2023] [Accepted: 01/16/2023] [Indexed: 01/20/2023] Open
Abstract
Scedosporium apiospermum is a saprophytic filamentous fungus involved in human infections, of which the virulence factors that contribute to pathogenesis are still poorly characterized. In particular, little is known about the specific role of dihydroxynaphtalene (DHN)-melanin, located on the external layer of the conidia cell wall. We previously identified a transcription factor, PIG1, which may be involved in DHN-melanin biosynthesis. To elucidate the role of PIG1 and DHN-melanin in S. apiospermum, a CRISPR-Cas9-mediated PIG1 deletion was carried out from two parental strains to evaluate its impact on melanin biosynthesis, conidia cell-wall assembly, and resistance to stress, including the ability to survive macrophage engulfment. ΔPIG1 mutants did not produce melanin and showed a disorganized and thinner cell wall, resulting in a lower survival rate when exposed to oxidizing conditions, or high temperature. The absence of melanin increased the exposure of antigenic patterns on the conidia surface. PIG1 regulates the melanization of S. apiospermum conidia, and is involved in the survival to environmental injuries and to the host immune response, that might participate in virulence. Moreover, a transcriptomic analysis was performed to explain the observed aberrant septate conidia morphology and found differentially expressed genes, underlining the pleiotropic function of PIG1.
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Affiliation(s)
- Hélène Guegan
- CHU Rennes, INSERM, EHESP, IRSET (Institut de Recherche en Santé Environnement et Travail)—UMR_S 1085, 35000 Rennes, France
- Correspondence: ; Tel.: +33-223233496
| | - Wilfried Poirier
- University of Angers, University of Brest, IRF, SFR ICAT, 49000 Angers, France
| | - Kevin Ravenel
- University of Angers, University of Brest, IRF, SFR ICAT, 49000 Angers, France
| | - Sarah Dion
- INSERM, EHESP, IRSET (Institut de Recherche en Santé Environnement et Travail)—UMR_S 1085, 35000 Rennes, France
| | - Aymeric Delabarre
- INSERM, EHESP, IRSET (Institut de Recherche en Santé Environnement et Travail)—UMR_S 1085, 35000 Rennes, France
| | - Dimitri Desvillechabrol
- Institut Pasteur, Université Paris Cité, Plate-Forme Technologique Biomics, 75015 Paris, France
- Institut Pasteur, Université Paris Cité, Bioinformatics and Biostatistics Hub, 75015 Paris, France
| | - Xavier Pinson
- CNRS, INSERM, Biosit UAR 3480 US_S 018, MRic Core Facility, 35000 Rennes, France
| | - Odile Sergent
- INSERM, EHESP, IRSET (Institut de Recherche en Santé Environnement et Travail)—UMR_S 1085, 35000 Rennes, France
| | - Isabelle Gallais
- INSERM, EHESP, IRSET (Institut de Recherche en Santé Environnement et Travail)—UMR_S 1085, 35000 Rennes, France
| | - Jean-Pierre Gangneux
- CHU Rennes, INSERM, EHESP, IRSET (Institut de Recherche en Santé Environnement et Travail)—UMR_S 1085, 35000 Rennes, France
| | - Sandrine Giraud
- University of Angers, University of Brest, IRF, SFR ICAT, 49000 Angers, France
| | - Amandine Gastebois
- University of Angers, University of Brest, IRF, SFR ICAT, 49000 Angers, France
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Wang C, Wang J, Zhang D, Cheng J, Zhu J, Yang Z. Identification and functional analysis of protein secreted by Alternaria solani. PLoS One 2023; 18:e0281530. [PMID: 36877688 PMCID: PMC9987770 DOI: 10.1371/journal.pone.0281530] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 01/25/2023] [Indexed: 03/07/2023] Open
Abstract
Early blight, caused by the necrotrophic fungus Alternaria solani, is an important foliar disease that causes major yield losses of potato. Effector proteins secreted by pathogens to host cells can inhibit host immune response to pathogens. Currently, the function of effector proteins secreted by A. solani during infection is poorly understood. In this study, we identified and characterized a novel candidate effector protein, AsCEP50. AsCEP50 is a secreted protein that is highly expressed throughout the infection stages of A. solani. Agrobacterium tumefaciens-mediated transient expression in Nicotiana benthamiana and tomato demonstrated that AsCEP50 is located on the plasma membrane of N. benthamiana and regulates senescence-related genes, resulting in the chlorosis of N. benthamiana and tomato leaves. Δ50 mutants were unaffected in vegetative growth, spore formation and mycelium morphology. However, the deletion of AsCEP50 significantly reduced virulence, melanin production and penetration of A. solani. These results strongly supported that AsCEP50 is an important pathogenic factor at the infection stage and contributes to the virulence of Alternaria solani.
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Affiliation(s)
- Chen Wang
- College of Plant Protection, Hebei Agricultural University, Baoding, P. R. China
| | - Jinhui Wang
- College of Plant Protection, Hebei Agricultural University, Baoding, P. R. China
| | - Dai Zhang
- College of Plant Protection, Hebei Agricultural University, Baoding, P. R. China
| | - Jianing Cheng
- College of Plant Protection, Hebei Agricultural University, Baoding, P. R. China
| | - Jiehua Zhu
- College of Plant Protection, Hebei Agricultural University, Baoding, P. R. China
- Technological Innovation Center for Biological Control of Crop Diseases and Insect Pests of Hebei Province, Baoding, P. R. China
- * E-mail: (JZ); (ZY)
| | - Zhihui Yang
- College of Plant Protection, Hebei Agricultural University, Baoding, P. R. China
- Technological Innovation Center for Biological Control of Crop Diseases and Insect Pests of Hebei Province, Baoding, P. R. China
- * E-mail: (JZ); (ZY)
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Wang C, Zhang D, Cheng J, Zhao D, Pan Y, Li Q, Zhu J, Yang Z, Wang J. Identification of effector CEP112 that promotes the infection of necrotrophic Alternaria solani. BMC PLANT BIOLOGY 2022; 22:466. [PMID: 36171557 PMCID: PMC9520946 DOI: 10.1186/s12870-022-03845-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 09/12/2022] [Indexed: 06/16/2023]
Abstract
BACKGROUND Alternaria solani is a typical necrotrophic pathogen that can cause severe early blight on Solanaceae crops and cause ring disease on plant leaves. Phytopathogens produce secretory effectors that regulate the host immune response and promote pathogenic infection. Effector proteins, as specialized secretions of host-infecting pathogens, play important roles in disrupting host defense systems. At present, the role of the effector secreted by A. solani during infection remains unclear. We report the identification and characterization of AsCEP112, an effector required for A. solani virulence. RESULT The AsCEP112 gene was screened from the transcriptome and genome of A. solani on the basis of typical effector signatures. Fluorescence quantification and transient expression analysis showed that the expression level of AsCEP112 continued to increase during infection. The protein localized to the cell membrane of Nicotiana benthamiana and regulated senescence-related genes, resulting in the chlorosis of N. benthamiana and tomato leaves. Moreover, comparative analysis of AsCEP112 mutant obtained by homologous recombination with wild-type and revertant strains indicated that AsCEP112 gene played an active role in regulating melanin formation and penetration in the pathogen. Deletion of AsCEP112 also reduced the pathogenicity of HWC-168. CONCLUSION Our findings demonstrate that AsCEP112 was an important effector protein that targeted host cell membranes. AsCEP112 regulateed host senescence-related genes to control host leaf senescence and chlorosis, and contribute to pathogen virulence.
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Affiliation(s)
- Chen Wang
- College of Plant Protection, Hebei Agricultural University, Baoding, 071001, People's Republic of China
| | - Dai Zhang
- College of Plant Protection, Hebei Agricultural University, Baoding, 071001, People's Republic of China
| | - Jianing Cheng
- College of Plant Protection, Hebei Agricultural University, Baoding, 071001, People's Republic of China
| | - Dongmei Zhao
- College of Plant Protection, Hebei Agricultural University, Baoding, 071001, People's Republic of China
| | - Yang Pan
- College of Plant Protection, Hebei Agricultural University, Baoding, 071001, People's Republic of China
| | - Qian Li
- College of Plant Protection, Hebei Agricultural University, Baoding, 071001, People's Republic of China
| | - Jiehua Zhu
- College of Plant Protection, Hebei Agricultural University, Baoding, 071001, People's Republic of China.
- Technological Innovation Center for Biological Control of Crop Diseases and Insect Pests of Hebei Province, Baoding, 071001, People's Republic of China.
| | - Zhihui Yang
- College of Plant Protection, Hebei Agricultural University, Baoding, 071001, People's Republic of China.
- Technological Innovation Center for Biological Control of Crop Diseases and Insect Pests of Hebei Province, Baoding, 071001, People's Republic of China.
| | - Jinhui Wang
- College of Plant Protection, Hebei Agricultural University, Baoding, 071001, People's Republic of China.
- Technological Innovation Center for Biological Control of Crop Diseases and Insect Pests of Hebei Province, Baoding, 071001, People's Republic of China.
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Li R, Li Y, Xu W, Zhang M, Jiang Q, Liu Y, Li L, Bi Y, Prusky DB. Transcription factor AacmrA mediated melanin synthesis regulates the growth, appressorium formation, stress response and pathogenicity of pear fungal Alternaria alternata. Fungal Biol 2022; 126:687-695. [DOI: 10.1016/j.funbio.2022.08.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 07/20/2022] [Accepted: 08/18/2022] [Indexed: 11/04/2022]
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Abstract
Contamination of food and feed with toxin-producing fungi is a major threat in agriculture and for human health. The filamentous fungus Alternaria alternata is one of the most widespread postharvest contaminants and a weak plant pathogen. It produces a large variety of secondary metabolites with alternariol and its derivatives as characteristic mycotoxin. Other important phyto- and mycotoxins are perylene quinones (PQs), some of which have anticancer properties. Here, we discovered that the PQ altertoxin (ATX) biosynthesis shares most enzymes with the 1,8-dihydroxynaphthalene (1,8-DHN) melanin pathway. However, melanin was formed in aerial hyphae and spores, and ATXs were synthesized in substrate hyphae. This spatial separation is achieved through the promiscuity of a polyketide synthase, presumably producing a pentaketide (T4HN), a hexaketide (AT4HN), and a heptaketide (YWA1) as products. T4HN directly enters the altertoxin and DHN melanin pathway, whereas AT4HN and YWA1 can be converted only in aerial hyphae, which probably leads to a higher T4HN concentration, favoring 1,8-DHN melanin formation. Whereas the production of ATXs was strictly dependent on the CmrA transcription factor, melanin could still be produced in the absence of CmrA to some extent. This suggests that different cues regulate melanin and toxin formation. Since DHN melanin is produced by many fungi, PQs or related compounds may be produced in many more fungi than so far assumed.
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Zhang M, Wang T, Li Y, Bi Y, Li R, Yuan J, Xu W, Prusky D. AaHog1 Regulates Infective Structural Differentiation Mediated by Physicochemical Signals from Pear Fruit Cuticular Wax, Stress Response, and Alternaria alternata Pathogenicity. J Fungi (Basel) 2022; 8:jof8030266. [PMID: 35330268 PMCID: PMC8952436 DOI: 10.3390/jof8030266] [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: 02/02/2022] [Revised: 03/02/2022] [Accepted: 03/04/2022] [Indexed: 11/16/2022] Open
Abstract
The high-osmolarity glycerol response kinase, Hog1, affects several cellular responses, but the precise regulatory role of the Hog1 mitogen-activated protein (MAP) kinase in the differentiation of the infective structure of Alternariaalternata induced by pear cuticular wax and hydrophobicity has not yet clarified. In this study, the AaHog1 in A. alternata was identified and functionally characterized. AaHog1 has threonine-glycine-tyrosine (TGY) phosphorylation sites. Moreover, the expression level of AaHog1 was significantly upregulated during the stages of appressorium formation of A. alternata on the fruit-wax-extract-coated GelBond hydrophobic film surface. Importantly, our results showed that the appressorium and infection hyphae formation rates were significantly reduced in ΔAaHog1 mutants. Furthermore, AaHog1 is beneficial for the growth and development, stress tolerance, virulence, and cell-wall-degrading enzyme activity of A. alternata. These findings may be useful for dissecting the AaHog1 regulatory mechanism in relation to the pathogenesis of A. alternata.
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Affiliation(s)
- Miao Zhang
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou 730070, China; (M.Z.); (T.W.); (Y.B.); (R.L.); (J.Y.); (W.X.); (D.P.)
| | - Tiaolan Wang
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou 730070, China; (M.Z.); (T.W.); (Y.B.); (R.L.); (J.Y.); (W.X.); (D.P.)
| | - Yongcai Li
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou 730070, China; (M.Z.); (T.W.); (Y.B.); (R.L.); (J.Y.); (W.X.); (D.P.)
- Correspondence:
| | - Yang Bi
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou 730070, China; (M.Z.); (T.W.); (Y.B.); (R.L.); (J.Y.); (W.X.); (D.P.)
| | - Rong Li
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou 730070, China; (M.Z.); (T.W.); (Y.B.); (R.L.); (J.Y.); (W.X.); (D.P.)
| | - Jing Yuan
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou 730070, China; (M.Z.); (T.W.); (Y.B.); (R.L.); (J.Y.); (W.X.); (D.P.)
| | - Wenyi Xu
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou 730070, China; (M.Z.); (T.W.); (Y.B.); (R.L.); (J.Y.); (W.X.); (D.P.)
| | - Dov Prusky
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou 730070, China; (M.Z.); (T.W.); (Y.B.); (R.L.); (J.Y.); (W.X.); (D.P.)
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization, The Volcani Center, Rishon LeZion 50250, Israel
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Fernandes C, Mota M, Barros L, Dias MI, Ferreira ICFR, Piedade AP, Casadevall A, Gonçalves T. Pyomelanin Synthesis in Alternaria alternata Inhibits DHN-Melanin Synthesis and Decreases Cell Wall Chitin Content and Thickness. Front Microbiol 2021; 12:691433. [PMID: 34512569 PMCID: PMC8430343 DOI: 10.3389/fmicb.2021.691433] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 07/26/2021] [Indexed: 12/15/2022] Open
Abstract
The genus Alternaria includes several of fungi that are darkly pigmented by DHN-melanin. These are pathogenic to plants but are also associated with human respiratory allergic diseases and with serious infections in immunocompromised individuals. The present work focuses on the alterations of the composition and structure of the hyphal cell wall of Alternaria alternata occuring under the catabolism of L-tyrosine and L-phenylalanine when cultured in minimal salt medium (MM). Under these growing conditions, we observed the released of a brown pigment into the culture medium. FTIR analysis demonstrates that the produced pigment is chemically identical to the pigment released when the fungus is grown in MM with homogentisate acid (HGA), the intermediate of pyomelanin, confirming that this pigment is pyomelanin. In contrast to other fungi that also synthesize pyomelanin under tyrosine metabolism, A. alternata inhibits DHN-melanin cell wall accumulation when pyomelanin is produced, and this is associated with reduced chitin cell wall content. When A. alternata is grown in MM containing L-phenylalanine, a L-tyrosine percursor, pyomelanin is synthesized but only at trace concentrations and A. alternata mycelia display an albino-like phenotype since DHN-melanin accumulation is inhibited. CmrA, the transcription regulator for the genes coding for the DHN-melanin pathway, is involved in the down-regulation of DHN-melanin synthesis when pyomelanin is being synthetized, since the CMRA gene and genes of the enzymes involved in DHN-melanin synthesis pathway showed a decreased expression. Other amino acids do not trigger pyomelanin synthesis and DHN-melanin accumulation in the cell wall is not affected. Transmission and scanning electron microscopy show that the cell wall structure and surface decorations are altered in L-tyrosine- and L-phenylalanine-grown fungi, depending on the pigment produced. In summary, growth in presence of L-tyrosine and L-phenylalanine leads to pigmentation and cell wall changes, which could be relevant to infection conditions where these amino acids are expected to be available.
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Affiliation(s)
- Chantal Fernandes
- CNC—Center for Neuroscience and Cell Biology of Coimbra, Coimbra, Portugal
| | - Marta Mota
- CNC—Center for Neuroscience and Cell Biology of Coimbra, Coimbra, Portugal
- FMUC—Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Lillian Barros
- Mountain Research Center (CIMO), Polytechnic Institute of Bragança, Bragança, Portugal
- Laboratory of Separation and Reaction Engineering - Laboratory of Catalysis and Materials (LSRE-LCM), Polytechnic Institute of Bragança, Bragança, Portugal
| | - Maria Inês Dias
- Mountain Research Center (CIMO), Polytechnic Institute of Bragança, Bragança, Portugal
- Laboratory of Separation and Reaction Engineering - Laboratory of Catalysis and Materials (LSRE-LCM), Polytechnic Institute of Bragança, Bragança, Portugal
| | - Isabel C. F. R. Ferreira
- Mountain Research Center (CIMO), Polytechnic Institute of Bragança, Bragança, Portugal
- Laboratory of Separation and Reaction Engineering - Laboratory of Catalysis and Materials (LSRE-LCM), Polytechnic Institute of Bragança, Bragança, Portugal
| | - Ana P. Piedade
- Centre for Mechanical Engineering, Materials and Processes, Department of Mechanical Engineering, University of Coimbra, Coimbra, Portugal
| | - Arturo Casadevall
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States
| | - Teresa Gonçalves
- CNC—Center for Neuroscience and Cell Biology of Coimbra, Coimbra, Portugal
- FMUC—Faculty of Medicine, University of Coimbra, Coimbra, Portugal
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12
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Wang X, Lu D, Tian C. Analysis of melanin biosynthesis in the plant pathogenic fungus Colletotrichum gloeosporioides. Fungal Biol 2021; 125:679-692. [PMID: 34420695 DOI: 10.1016/j.funbio.2021.04.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Revised: 04/04/2021] [Accepted: 04/19/2021] [Indexed: 11/25/2022]
Abstract
Melanin is recognized as a dark pigment that can protect fungi from the harm of environmental stresses. To investigate what roles of melanin played in the pathogenicity and development of Colletotrichum gloeosporioides, a causal agent of poplar anthracnose, genes encoding a transcription factor CgCmr1 and a polyketide synthase CgPks1 were isolated as the ortholog of Magnaporthe oryzae Pig1 and Pks1 respectively. Deletion of CgCmr1 or CgPks1 resulted in melanin-deficient fungal colony. The ΔCgPks1 mutant showed no melanin accumulation in appressoria, and lack of CgCmr1 also resulted in the delayed and decreased melanization of appressoria. In addition, the turgor pressure of the appressorium was lower in ΔCgPks1 and ΔCgCmr1 than in the wild-type (WT). However, DHN melanin was not a vital factor for virulence in C. gloeosporioides. Moreover, deletion of CgCmr1 and CgPks1 resulted in the hypersensitivity to hydrogen peroxide (H2O2) oxidative stress but not to other abiotic stresses. Collectively, these results suggest that CgCmr1 and CgPks1 play an important role in DHN melanin biosynthesis, and melanin was not an essential factor in penetration and pathogenicity in C. gloeosporioides. The data presented in this study will facilitate future evaluations of the melanin biosynthetic pathway and development in filamentous fungi.
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Affiliation(s)
- Xiaolian Wang
- The Key Laboratory for Silviculture and Conservation of Ministry of Education, College of Forestry, Beijing Forestry University, Beijing, China
| | - Dongxiao Lu
- The Key Laboratory for Silviculture and Conservation of Ministry of Education, College of Forestry, Beijing Forestry University, Beijing, China
| | - Chengming Tian
- The Key Laboratory for Silviculture and Conservation of Ministry of Education, College of Forestry, Beijing Forestry University, Beijing, China.
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13
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Zhang Z, Jia H, Liu N, Li H, Meng Q, Wu N, Cao Z, Dong J. The zinc finger protein StMR1 affects the pathogenicity and melanin synthesis of Setosphaeria turcica and directly regulates the expression of DHN melanin synthesis pathway genes. Mol Microbiol 2021; 117:261-273. [PMID: 34278632 DOI: 10.1111/mmi.14786] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 07/12/2021] [Accepted: 07/13/2021] [Indexed: 11/28/2022]
Abstract
The infection and colonization of pathogenic fungi are often regulated by transcription factors. In our previous study, the zinc finger protein-encoding gene StMR1 was found to be highly expressed during the infection process of Setosphaeria turcica, the pathogen causing northern corn leaf blight. Evolutionary tree analysis showed that this gene was associated with regulatory factors of melanin synthesis. However, the regulatory mechanism of melanin synthesis and its effect on pathogenicity remain unclear. In this study, the function of StMR1 was analyzed by gene knockout. When the expression level of StMR1 in the mutants was significantly reduced, the colony color became lighter, the mycelia were curved and transparent, and the mutant showed a significant loss of pathogenicity. In addition, compared with wild-type, the accumulation of melanin decreased significantly in △Stmr1. RNA-seq analysis revealed 1,981 differentially expressed genes between the wild-type and knockout mutant, among which 39 genes were involved in melanin metabolism. qPCR revealed that the expression levels of 6 key genes in the melanin synthesis pathway were significantly reduced. ChIP-PCR and yeast one-hybrid assays confirmed that StMR1 directly binds to the promoters of St3HNR, St4HNR, StPKS, and StLAC2 in the DHN melanin synthesis pathway and regulates gene expression. The C2H2-type zinc fingers and Zn(Ⅱ)2Cys6 binuclear cluster in StMR1 was important for the binding to targets.
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Affiliation(s)
- Zexue Zhang
- State Key Laboratory of North China Crop Improvement and Regulation/Key Laboratory of Hebei Province for Plant Physiology and Molecular Pathology, Hebei Agricultural University, Mycotoxin and Molecular Plant Pathology Laboratory, Hebei Agricultural University, Baoding, 071001, P.R.China
| | - Hui Jia
- State Key Laboratory of North China Crop Improvement and Regulation/Key Laboratory of Hebei Province for Plant Physiology and Molecular Pathology, Hebei Agricultural University, Mycotoxin and Molecular Plant Pathology Laboratory, Hebei Agricultural University, Baoding, 071001, P.R.China
| | - Ning Liu
- State Key Laboratory of North China Crop Improvement and Regulation/Key Laboratory of Hebei Province for Plant Physiology and Molecular Pathology, Hebei Agricultural University, Mycotoxin and Molecular Plant Pathology Laboratory, Hebei Agricultural University, Baoding, 071001, P.R.China
| | - Haixiao Li
- State Key Laboratory of North China Crop Improvement and Regulation/Key Laboratory of Hebei Province for Plant Physiology and Molecular Pathology, Hebei Agricultural University, Mycotoxin and Molecular Plant Pathology Laboratory, Hebei Agricultural University, Baoding, 071001, P.R.China
| | - Qingjiang Meng
- State Key Laboratory of North China Crop Improvement and Regulation/Key Laboratory of Hebei Province for Plant Physiology and Molecular Pathology, Hebei Agricultural University, Mycotoxin and Molecular Plant Pathology Laboratory, Hebei Agricultural University, Baoding, 071001, P.R.China
| | - Nan Wu
- State Key Laboratory of North China Crop Improvement and Regulation/Key Laboratory of Hebei Province for Plant Physiology and Molecular Pathology, Hebei Agricultural University, Mycotoxin and Molecular Plant Pathology Laboratory, Hebei Agricultural University, Baoding, 071001, P.R.China
| | - Zhiyan Cao
- State Key Laboratory of North China Crop Improvement and Regulation/Key Laboratory of Hebei Province for Plant Physiology and Molecular Pathology, Hebei Agricultural University, Mycotoxin and Molecular Plant Pathology Laboratory, Hebei Agricultural University, Baoding, 071001, P.R.China
| | - Jingao Dong
- State Key Laboratory of North China Crop Improvement and Regulation/Key Laboratory of Hebei Province for Plant Physiology and Molecular Pathology, Hebei Agricultural University, Mycotoxin and Molecular Plant Pathology Laboratory, Hebei Agricultural University, Baoding, 071001, P.R.China
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14
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Genetic Relationships in the Toxin-Producing Fungal Endophyte, Alternaria oxytropis Using Polyketide Synthase and Non-Ribosomal Peptide Synthase Genes. J Fungi (Basel) 2021; 7:jof7070538. [PMID: 34356917 PMCID: PMC8306250 DOI: 10.3390/jof7070538] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 06/29/2021] [Accepted: 06/30/2021] [Indexed: 01/16/2023] Open
Abstract
The legume Oxytropis sericea hosts a fungal endophyte, Alternaria oxytropis, which produces secondary metabolites (SM), including the toxin swainsonine. Polyketide synthase (PKS) and non-ribosomal peptide synthase (NRPS) enzymes are associated with biosynthesis of fungal SM. To better understand the origins of the SM, an unannotated genome of A. oxytropis was assessed for protein sequences similar to known PKS and NRPS enzymes of fungi. Contigs exhibiting identity with known genes were analyzed at nucleotide and protein levels using available databases. Software were used to identify PKS and NRPS domains and predict identity and function. Confirmation of sequence for selected gene sequences was accomplished using PCR. Thirteen PKS, 5 NRPS, and 4 PKS-NRPS hybrids were identified and characterized with functions including swainsonine and melanin biosynthesis. Phylogenetic relationships among closest amino acid matches with Alternaria spp. were identified for seven highly conserved PKS and NRPS, including melanin synthesis. Three PKS and NRPS were most closely related to other fungi within the Pleosporaceae family, while five PKS and PKS-NRPS were closely related to fungi in the Pleosporales order. However, seven PKS and PKS-NRPS showed no identity with fungi in the Pleosporales or the class Dothideomycetes, suggesting a different evolutionary origin for those genes.
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15
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John E, Singh KB, Oliver RP, Tan K. Transcription factor control of virulence in phytopathogenic fungi. MOLECULAR PLANT PATHOLOGY 2021; 22:858-881. [PMID: 33973705 PMCID: PMC8232033 DOI: 10.1111/mpp.13056] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 03/02/2021] [Accepted: 03/04/2021] [Indexed: 05/12/2023]
Abstract
Plant-pathogenic fungi are a significant threat to economic and food security worldwide. Novel protection strategies are required and therefore it is critical we understand the mechanisms by which these pathogens cause disease. Virulence factors and pathogenicity genes have been identified, but in many cases their roles remain elusive. It is becoming increasingly clear that gene regulation is vital to enable plant infection and transcription factors play an essential role. Efforts to determine their regulatory functions in plant-pathogenic fungi have expanded since the annotation of fungal genomes revealed the ubiquity of transcription factors from a broad range of families. This review establishes the significance of transcription factors as regulatory elements in plant-pathogenic fungi and provides a systematic overview of those that have been functionally characterized. Detailed analysis is provided on regulators from well-characterized families controlling various aspects of fungal metabolism, development, stress tolerance, and the production of virulence factors such as effectors and secondary metabolites. This covers conserved transcription factors with either specialized or nonspecialized roles, as well as recently identified regulators targeting key virulence pathways. Fundamental knowledge of transcription factor regulation in plant-pathogenic fungi provides avenues to identify novel virulence factors and improve our understanding of the regulatory networks linked to pathogen evolution, while transcription factors can themselves be specifically targeted for disease control. Areas requiring further insight regarding the molecular mechanisms and/or specific classes of transcription factors are identified, and direction for future investigation is presented.
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Affiliation(s)
- Evan John
- Centre for Crop and Disease ManagementCurtin UniversityBentleyWestern AustraliaAustralia
- School of Molecular and Life SciencesCurtin UniversityBentleyWestern AustraliaAustralia
| | - Karam B. Singh
- Agriculture and FoodCommonwealth Scientific and Industrial Research OrganisationFloreatWestern AustraliaAustralia
| | - Richard P. Oliver
- School of Molecular and Life SciencesCurtin UniversityBentleyWestern AustraliaAustralia
| | - Kar‐Chun Tan
- Centre for Crop and Disease ManagementCurtin UniversityBentleyWestern AustraliaAustralia
- School of Molecular and Life SciencesCurtin UniversityBentleyWestern AustraliaAustralia
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16
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Zhang M, Li Y, Wang T, Bi Y, Li R, Huang Y, Mao R, Jiang Q, Liu Y, Prusky DB. AaPKAc Regulates Differentiation of Infection Structures Induced by Physicochemical Signals From Pear Fruit Cuticular Wax, Secondary Metabolism, and Pathogenicity of Alternaria alternata. FRONTIERS IN PLANT SCIENCE 2021; 12:642601. [PMID: 33968101 PMCID: PMC8096925 DOI: 10.3389/fpls.2021.642601] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 03/16/2021] [Indexed: 05/03/2023]
Abstract
Alternaria alternata, the casual agent of black rot of pear fruit, can sense and respond to the physicochemical cues from the host surface and form infection structures during infection. To evaluate the role of cyclic AMP-dependent protein kinase (cAMP-PKA) signaling in surface sensing of A. alternata, we isolated and functionally characterized the cyclic adenosine monophosphate-dependent protein kinase A catalytic subunit gene (AaPKAc). Gene expression results showed that AaPKAc was strongly expressed during the early stages of appressorium formation on hydrophobic surfaces. Knockout mutants ΔAaPKAc were generated by replacing the target genes via homologous recombination events. We found that intracellular cAMP content increased but PKA content decreased in ΔAaPKAc mutant strain. Appressorium formation and infection hyphae were reduced in the ΔAaPKAc mutant strain, and the ability of the ΔAaPKAc mutant strain to recognize and respond to high hydrophobicity surfaces and different surface waxes was lower than in the wild type (WT) strain. In comparison with the WT strain, the appressorium formation rate of the ΔAaPKAc mutant strain on high hydrophobicity and fruit wax extract surface was reduced by 31.6 and 49.3% 4 h after incubation, respectively. In addition, AaPKAc is required for the hypha growth, biomass, pathogenicity, and toxin production of A. alternata. However, AaPKAc negatively regulated conidia formation, melanin production, and osmotic stress resistance. Collectively, AaPKAc is required for pre-penetration, developmental, physiological, and pathological processes in A. alternata.
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Affiliation(s)
- Miao Zhang
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, China
| | - Yongcai Li
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, China
- *Correspondence: Yongcai Li,
| | - Tiaolan Wang
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, China
| | - Yang Bi
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, China
| | - Rong Li
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, China
| | - Yi Huang
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, China
| | - Renyan Mao
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, China
| | - Qianqian Jiang
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, China
| | - Yongxiang Liu
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, China
| | - Dov B. Prusky
- College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, China
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel
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17
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Fu H, Chung K, Gai Y, Mao L, Li H. The basal transcription factor II H subunit Tfb5 is required for stress response and pathogenicity in the tangerine pathotype of Alternaria alternata. MOLECULAR PLANT PATHOLOGY 2020; 21:1337-1352. [PMID: 32776683 PMCID: PMC7488464 DOI: 10.1111/mpp.12982] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 06/25/2020] [Accepted: 07/20/2020] [Indexed: 05/16/2023]
Abstract
The basal transcription factor II H (TFIIH) is a multicomponent complex. In the present study, we characterized a TFIIH subunit Tfb5 by analysing loss- and gain-of-function mutants to gain a better understanding of the molecular mechanisms underlying stress resistance and pathogenicity in the citrus fungal pathogen Alternaria alternata. Tfb5 deficiency mutants (ΔAatfb5) decreased sporulation and pigmentation, and were impaired in the maintenance of colony surface hydrophobicity and cell wall integrity. ΔAatfb5 increased sensitivity to ultraviolet light, DNA-damaging agents, and oxidants. The expression of Aatfb5 was up-regulated in the wild type upon infection in citrus leaves, implicating the requirement of Aatfb5 in fungal pathogenesis. Biochemical and virulence assays revealed that ΔAatfb5 was defective in toxin production and cellwall-degrading enzymes, and failed to induce necrotic lesions on detached citrus leaves. Aatfb5 fused with green fluorescent protein (GFP) was localized in the cytoplasm and nucleus and physically interacted with another subunit, Tfb2, based on yeast two-hybrid and co-immunoprecipitation analyses. Transcriptome and Antibiotics & Secondary Metabolite Analysis Shell (antiSMASH) analyses revealed the positive and negative roles of Aatfb5 in the production of various secondary metabolites and in the regulation of many metabolic and biosynthetic processes in A. alternata. Aatfb5 may play a negative role in oxidative phosphorylation and a positive role in peroxisome biosynthesis. Two cutinase-coding genes (AaCut2 and AaCut15) required for full virulence were down-regulated in ΔAatfb5. Overall, this study expands our understanding of how A. alternata uses the basal transcription factor to deal with stress and achieve successful infection in the plant host.
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Affiliation(s)
- Huilan Fu
- Key Laboratory of Molecular Biology of Crop Pathogens and InsectsInstitute of BiotechnologyZhejiang UniversityHangzhouChina
| | - Kuang‐Ren Chung
- Department of Plant PathologyCollege of Agriculture and Natural ResourcesNational Chung‐Hsing UniversityTaichungTaiwan
| | - Yunpeng Gai
- Key Laboratory of Molecular Biology of Crop Pathogens and InsectsInstitute of BiotechnologyZhejiang UniversityHangzhouChina
| | - Lijuan Mao
- Analysis Center of Agrobiology and Environmental SciencesFaculty of Agriculture, Life and Environment SciencesZhejiang UniversityHangzhouChina
| | - Hongye Li
- Key Laboratory of Molecular Biology of Crop Pathogens and InsectsInstitute of BiotechnologyZhejiang UniversityHangzhouChina
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18
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Charlton ND, Yi M, Bock CH, Zhang M, Young CA. First description of the sexual stage of Venturia effusa, causal agent of pecan scab. Mycologia 2020; 112:711-721. [PMID: 32469692 DOI: 10.1080/00275514.2020.1759998] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Pecan scab, caused by Venturia effusa, is the most prevalent disease of pecan in the southeastern United States. Recent characterization of the mating type (MAT) distribution of V. effusa revealed that the MAT idiomorphs are in equilibrium at various spatial scales, indicative of regular sexual recombination. However, the occurrence of the sexual stage of V. effusa has never been observed, and the pathogen was previously considered to rely entirely on asexual reproduction. We were able to generate the sexual stage by pairing isolates of opposite mating types on oatmeal culture media. Cultures were incubated at 24 C for 2 mo to allow hyphae from isolates of each mating type to interact. Culture plates were then incubated at 4 C for 4 mo, after which immature pseudothecia were observed. Following exposure to a 12-h photoperiod for 2 wk at 24 C, asci and ascospores readily developed. Pseudothecium and ascospore production was optimal when incubated for 4 mo at 4 C. We utilized progeny from a cross of an albino isolate and wild-type (melanized) isolates to determine that recombination had occurred. Multilocus genotyping using 32 microsatellite markers confirmed that progeny were the result of recombination, which was further supported by segregation of mating types and culture pigmentation. Albino progeny were all confirmed to contain the same mutation in the polyketide synthase (PKS1) melanin biosynthesis gene as the albino parent. The results of this study demonstrate the heterothallic nature of V. effusa. The impact of determining the source of the overwintering ascostroma will aid in management decisions to reduce the primary inoculum in the disease cycle.
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Affiliation(s)
| | - Mihwa Yi
- Noble Research Institute , LLC, Ardmore, Oklahoma 73401
| | - Clive H Bock
- Southeastern Fruit and Tree Nut Research Laboratory, Agricultural Research Service, United States Department of Agriculture , Byron, Georgia 31008
| | - Minling Zhang
- Southeastern Fruit and Tree Nut Research Laboratory, Agricultural Research Service, United States Department of Agriculture , Byron, Georgia 31008
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19
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Winter DJ, Charlton ND, Krom N, Shiller J, Bock CH, Cox MP, Young CA. Chromosome-Level Reference Genome of Venturia effusa, Causative Agent of Pecan Scab. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2020; 33:149-152. [PMID: 31631770 DOI: 10.1094/mpmi-08-19-0236-a] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Pecan scab, caused by Venturia effusa, is a devastating disease of pecan (Carya illinoinensis), which results in economic losses on susceptible cultivars throughout the southeastern United States. To enhance our understanding of pathogenicity in V. effusa, we have generated a complete telomere-to-telomere reference genome of V. effusa isolate FRT5LL7-Albino. By combining Illumina MiSeq and Oxford Nanopore MinION data, we assembled a 45.2-Mb genome represented by 20 chromosomes and containing 10,820 putative genes, of which 7,619 have at least one functional annotation. The likely causative mutation of the albino phenotype was identified as a single base insertion and a resulting frameshift in the gene encoding the polyketide synthase ALM1. This genome represents the first full chromosome-level assembly of any Venturia sp.
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Affiliation(s)
- David J Winter
- School of Fundamental Sciences and the Bio-Protection Research Centre, Massey University, Palmerston North 4442, New Zealand
| | | | - Nick Krom
- Noble Research Institute, LLC, Ardmore, OK 73401, U.S.A
| | - Jason Shiller
- Noble Research Institute, LLC, Ardmore, OK 73401, U.S.A
| | - Clive H Bock
- United States Department of Agriculture-Agricultural Research Service Southeastern Fruit and Tree Nut Research Laboratory, Byron, GA 31008, U.S.A
| | - Murray P Cox
- School of Fundamental Sciences and the Bio-Protection Research Centre, Massey University, Palmerston North 4442, New Zealand
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20
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Harting R, Höfer A, Tran VT, Weinhold LM, Barghahn S, Schlüter R, Braus GH. The Vta1 transcriptional regulator is required for microsclerotia melanization in Verticillium dahliae. Fungal Biol 2020; 124:490-500. [PMID: 32389312 DOI: 10.1016/j.funbio.2020.01.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 01/20/2020] [Accepted: 01/21/2020] [Indexed: 12/13/2022]
Abstract
Many fungi are able to produce resting structures, which ensure survival and protect them against various stresses in their habitat such as exposure to UV light, temperature variations, drought as well as changing pH and nutrient conditions. Verticillium dahliae is a plant pathogenic fungus that forms melanized resting structures, called microsclerotia, for survival of time periods without a host. These highly stress resistant microsclerotia persist in the soil for many years and are therefore problematic for an effective treatment of the fungus. The Verticillium transcription activator of adhesion 1 (Vta1) was initially identified as one of several transcriptional regulators that rescue adhesion in non-adhesive Saccharomyces cerevisiae cells. Vta2 and Vta3 are required for early steps in plant infection and colonization and additionally control microsclerotia formation. Here, we show that Vta1 function is different, because it is dispensable for root colonization and infection. Vta1 is produced in the fungal cell during microsclerotia development. Analysis of the deletion mutant revealed that the absence of Vta1 allows microsclerotia production, but they are colorless and no more melanized. Vta1 is required for melanin production and activates transcription of melanin biosynthesis genes including the polyketide synthase encoding PKS1 and the laccase LAC1. The primary function of Vta1 in melanin production is important for survival of microsclerotia as resting structures of V. dahliae.
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Affiliation(s)
- Rebekka Harting
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, University of Göttingen and Göttingen Center for Molecular Biosciences (GZMB), Grisebachstr. 8, D-37077 Göttingen, Germany
| | - Annalena Höfer
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, University of Göttingen and Göttingen Center for Molecular Biosciences (GZMB), Grisebachstr. 8, D-37077 Göttingen, Germany
| | - Van-Tuan Tran
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, University of Göttingen and Göttingen Center for Molecular Biosciences (GZMB), Grisebachstr. 8, D-37077 Göttingen, Germany
| | - Lisa-Maria Weinhold
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, University of Göttingen and Göttingen Center for Molecular Biosciences (GZMB), Grisebachstr. 8, D-37077 Göttingen, Germany
| | - Sina Barghahn
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, University of Göttingen and Göttingen Center for Molecular Biosciences (GZMB), Grisebachstr. 8, D-37077 Göttingen, Germany
| | - Rabea Schlüter
- Imaging Center of the Department of Biology, University of Greifswald, Friedrich-Ludwig-Jahn-Str. 15, D-17489 Greifswald, Germany
| | - Gerhard H Braus
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, University of Göttingen and Göttingen Center for Molecular Biosciences (GZMB), Grisebachstr. 8, D-37077 Göttingen, Germany.
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21
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Fang Y, Klosterman SJ, Tian C, Wang Y. Insights into VdCmr1-mediated protection against high temperature stress and UV irradiation in Verticillium dahliae. Environ Microbiol 2019; 21:2977-2996. [PMID: 31136051 DOI: 10.1111/1462-2920.14695] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 05/21/2019] [Accepted: 05/24/2019] [Indexed: 12/21/2022]
Abstract
The fungus Verticillium dahliae causes vascular wilt disease on more than 200 plant species worldwide. This fungus can survive for years in soil as melanized microsclerotia. We found that VdCmr1, a transcription factor, is required for the melanin production and increased survival following UV irradiation in V. dahliae but not for microsclerotia production or virulence. Here, we provided evidence how VdCmr1 protects against high temperature (HT) and UV irradiation in V. dahliae. The results indicate that VdCmr1 mediates entry to the diapause period in V. dahliae in response to HT and contributes to the expression of proteins to minimize protein misfolding and denaturation. VdCmr1 deletion results in the misregulation of DNA repair machinery, suggestive of reduced DNA repair capacity following UV irradiation and in correlation with the low survival rate of UV-treated VdCmr1 mutants. We discovered a putative VdCmr1-dependent gene cluster associated with secondary metabolism and stress responses. We also functionally characterized two VdCmr1-responsive genes participating in HT and UV response. These results shed further light on the roles of VdCmr1 in protection from HT or UV irradiation, and the additional insights into the mechanisms of this protection may be useful to exploit for more effective disease control.
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Affiliation(s)
- Yulin Fang
- Beijing Key Laboratory for Forest Pest Control, College of Forestry, Beijing Forestry University, Beijing, China
| | - Steven J Klosterman
- U.S. Department of Agriculture-Agricultural Research Service, Salinas, CA, 93905, USA
| | - Chengming Tian
- Beijing Key Laboratory for Forest Pest Control, College of Forestry, Beijing Forestry University, Beijing, China
| | - Yonglin Wang
- Beijing Key Laboratory for Forest Pest Control, College of Forestry, Beijing Forestry University, Beijing, China
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22
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Griffiths SA, Cox RJ, Overdijk EJR, Mesarich CH, Saccomanno B, Lazarus CM, de Wit PJGM, Collemare J. Assignment of a dubious gene cluster to melanin biosynthesis in the tomato fungal pathogen Cladosporium fulvum. PLoS One 2018; 13:e0209600. [PMID: 30596695 PMCID: PMC6312243 DOI: 10.1371/journal.pone.0209600] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 12/07/2018] [Indexed: 12/17/2022] Open
Abstract
Pigments and phytotoxins are crucial for the survival and spread of plant pathogenic fungi. The genome of the tomato biotrophic fungal pathogen Cladosporium fulvum contains a predicted gene cluster (CfPKS1, CfPRF1, CfRDT1 and CfTSF1) that is syntenic with the characterized elsinochrome toxin gene cluster in the citrus pathogen Elsinoë fawcettii. However, a previous phylogenetic analysis suggested that CfPks1 might instead be involved in pigment production. Here, we report the characterization of the CfPKS1 gene cluster to resolve this ambiguity. Activation of the regulator CfTSF1 specifically induced the expression of CfPKS1 and CfRDT1, but not of CfPRF1. These co-regulated genes that define the CfPKS1 gene cluster are orthologous to genes involved in 1,3-dihydroxynaphthalene (DHN) melanin biosynthesis in other fungi. Heterologous expression of CfPKS1 in Aspergillus oryzae yielded 1,3,6,8-tetrahydroxynaphthalene, a typical precursor of DHN melanin. Δcfpks1 deletion mutants showed similar altered pigmentation to wild type treated with DHN melanin inhibitors. These mutants remained virulent on tomato, showing this gene cluster is not involved in pathogenicity. Altogether, our results showed that the CfPKS1 gene cluster is involved in the production of DHN melanin and suggests that elsinochrome production in E. fawcettii likely involves another gene cluster.
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Affiliation(s)
- Scott A. Griffiths
- Fungal Natural Products, Westerdijk Fungal Biodiversity Institute, CT, Utrecht, The Netherlands
- Laboratory of Phytopathology, Wageningen University, Wageningen, The Netherlands
| | - Russell J. Cox
- Institut für Organische Chemie, Leibniz Universität Hannover, Hannover
| | - Elysa J. R. Overdijk
- Laboratory of Phytopathology, Wageningen University, Wageningen, The Netherlands
- Laboratory of Cell Biology, Wageningen University, Wageningen, The Netherlands
| | - Carl H. Mesarich
- Laboratory of Phytopathology, Wageningen University, Wageningen, The Netherlands
| | - Benedetta Saccomanno
- Laboratory of Phytopathology, Wageningen University, Wageningen, The Netherlands
| | - Colin M. Lazarus
- School of Biological Sciences, University of Bristol, Bristol, United Kingdom
| | | | - Jérôme Collemare
- Fungal Natural Products, Westerdijk Fungal Biodiversity Institute, CT, Utrecht, The Netherlands
- Laboratory of Phytopathology, Wageningen University, Wageningen, The Netherlands
- * E-mail:
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23
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Luo C, Zhao H, Yang X, Qiang C, Cheng J, Xie J, Chen T, Jiang D, Fu Y. Functional Analysis of the Melanin-Associated Gene CmMR1 in Coniothyrium minitans. Front Microbiol 2018; 9:2658. [PMID: 30467498 PMCID: PMC6237101 DOI: 10.3389/fmicb.2018.02658] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2018] [Accepted: 10/18/2018] [Indexed: 11/14/2022] Open
Abstract
Coniothyrium minitans is a sclerotial parasite, which has been investigated for commercial control of crop diseases caused by Sclerotinia sclerotiorum. Previously, we obtained a T-DNA insertional mutant, ZS-1TN24363, which did not produce melanin during conidiation. To understand the function of melanin in C. minitans, we cloned the gene that was disrupted by the T-DNA insertion, and found that this gene, called CmMR1, encoded a putative protein of 1,011 amino acids, which is a homolog of the transcription factor MR. Full-length CmMR1 contains 3,167 bp, with three exons and two introns. To confirm that the disrupted gene is responsible for the melanin-deficiency of the mutant, CmMR1 was disrupted and three targeted knockout mutants were obtained. Biological assays showed that the phenotype of the targeted knockout mutants was similar to that of the T-DNA insertional mutant. Furthermore, gene complementation confirmed that CmMR1 is responsible for the mutant phenotype. CmMR1 disruption did not affect hyphal growth, conidiation, and parasitization of C. minitans, however, the ROS accumulation increased and tolerance to UV light decreased significantly in the mutants. Our result may enhance the understanding of melanin in the ecology of C. minitans on molecular level.
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Affiliation(s)
- Chenwei Luo
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,The Provincial Key Lab of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Huizhang Zhao
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,The Provincial Key Lab of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Xiaoxiang Yang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,The Provincial Key Lab of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Cuicui Qiang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,The Provincial Key Lab of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Jiasen Cheng
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,The Provincial Key Lab of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Jiatao Xie
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,The Provincial Key Lab of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Tao Chen
- The Provincial Key Lab of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Daohong Jiang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,The Provincial Key Lab of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Yanping Fu
- The Provincial Key Lab of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
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24
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Development of an Expression Vector to Overexpress or Downregulate Genes in Curvularia protuberata. J Fungi (Basel) 2018; 4:jof4020054. [PMID: 29734743 PMCID: PMC6023383 DOI: 10.3390/jof4020054] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Revised: 05/03/2018] [Accepted: 05/03/2018] [Indexed: 12/13/2022] Open
Abstract
Curvularia protuberata, an endophytic fungus in the Ascomycota, provides plants with thermotolerance only when it carries a mycovirus known as Curvularia thermotolerance virus (CThTV), and forms a three-way symbiotic relationship among these organisms. Under heat stress, several genes are expressed differently between virus-free C. protuberata (VF) and C. protuberata carrying CThTV (AN). We developed an expression vector, pM2Z-fun, carrying a zeocin resistance gene driven by the ToxA promoter, to study gene functions in C. protuberata to better understand this three-way symbiosis. Using this new 3.7-kb vector, five genes that are differentially expressed in C. protuberata—including genes involved in the trehalose, melanin, and catalase biosynthesis pathways—were successfully overexpressed or downregulated in VF or AN C. protuberata strains, respectively. The VF overexpression lines showed higher metabolite and enzyme activity than in the control VF strain. Furthermore, downregulation of expression of the same genes in the AN strain resulted in lower metabolite and enzyme activity than in the control AN strain. The newly generated expression vector, pM2Z-fun, has been successfully used to express target genes in C. protuberata and will be useful in further functional expression studies in other Ascomycota fungi.
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25
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Zhou Y, Yang L, Wu M, Chen W, Li G, Zhang J. A Single-Nucleotide Deletion in the Transcription Factor Gene bcsmr1 Causes Sclerotial-Melanogenesis Deficiency in Botrytis cinerea. Front Microbiol 2017; 8:2492. [PMID: 29312200 PMCID: PMC5733056 DOI: 10.3389/fmicb.2017.02492] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 11/30/2017] [Indexed: 12/21/2022] Open
Abstract
Botrytis cinerea is an important plant pathogenic fungus with a wide range of host. It usually produces black-colored sclerotia (BS) due to deposition of 1,8-dihydroxynaphthalene melanin in sclerotial melanogenesis. Our previous study (Zhou et al., 2018) reported six B. cinerea isolates producing orange-colored sclerotia (OS) with deficiency in sclerotial melanogenesis. Comparison of ecological fitness (conidia, mycelia, sclerotia), natural distribution, and melanogenesis of selected BS and OS isolates suggests that sclerotia play an important role in the disease cycle caused by B. cinerea. However, the molecular mechanism for formation of the OS B. cinerea remains unknown. This study was done to unravel the molecular mechanism for the sclerotial melanogenesis deficiency in the OS isolates. We found that all the five sclerotial melanogenesis genes (bcpks12, bcygh1, bcbrn1/2, bcscd1) were down-regulated in OS isolates, compared to the genes in the BS isolates. However, the sclerotial melanogenesis-regulatory gene bcsmr1 had similar expression in both types of sclerotia, suggesting the sclerotial melanogenesis deficiency is due to loss-of-function of bcsmr1, rather than lack of expression of bcsmr1. Therefore, we cloned bcsmr1 from OS (bcsmr1OS ) and BS (bcsmr1BS ) isolates, and found a single-nucleotide deletion in bcsmr1OS . The single-nucleotide deletion caused formation of a premature stop codon in the open reading frame of bcsmr1OS , resulting in production of a 465-aa truncated protein. The transcription activity of the truncated protein was greatly reduced, compared to that of the 935-aa full-length protein encoded by bcsmr1BS in the BS isolates. The function of bcsmr1OS was partially complemented by bcsmr1BS . This study not only elucidated the molecular mechanism for formation of orange-colored sclerotia by the spontaneous mutant XN-1 of B. cinerea, but also confirmed the regulatory function of bcsmr1 in sclerotial melanogenesis of B. cinerea.
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Affiliation(s)
- Yingjun Zhou
- State Key Laboratory of Agricultural Microbiology and Key Laboratory of Plant Pathology of Hubei Province, Huazhong Agricultural University, Wuhan, China
- Laboratory of Biological Processing, Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha, China
| | - Long Yang
- State Key Laboratory of Agricultural Microbiology and Key Laboratory of Plant Pathology of Hubei Province, Huazhong Agricultural University, Wuhan, China
| | - Mingde Wu
- State Key Laboratory of Agricultural Microbiology and Key Laboratory of Plant Pathology of Hubei Province, Huazhong Agricultural University, Wuhan, China
| | - Weidong Chen
- United States Department of Agriculture, Agricultural Research Service, Washington State University, Pullman, WA, United States
| | - Guoqing Li
- State Key Laboratory of Agricultural Microbiology and Key Laboratory of Plant Pathology of Hubei Province, Huazhong Agricultural University, Wuhan, China
| | - Jing Zhang
- State Key Laboratory of Agricultural Microbiology and Key Laboratory of Plant Pathology of Hubei Province, Huazhong Agricultural University, Wuhan, China
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26
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Wenderoth M, Pinecker C, Voß B, Fischer R. Establishment of CRISPR/Cas9 in Alternaria alternata. Fungal Genet Biol 2017; 101:55-60. [PMID: 28286319 DOI: 10.1016/j.fgb.2017.03.001] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Revised: 03/05/2017] [Accepted: 03/06/2017] [Indexed: 10/20/2022]
Abstract
The filamentous fungus Alternaria alternata is a potent producer of many secondary metabolites, some of which like alternariol or alternariol-methyl ether are toxic and/or cancerogenic. Many Alternaria species do not only cause post-harvest losses of food and feed, but are aggressive plant pathogens. Despite the great economic importance and the large number of research groups working with the fungus, the molecular toolbox is rather underdeveloped. Gene deletions often result in heterokaryotic strains and therefore, gene-function analyses are rather tedious. In addition, A. alternata lacks a sexual cycle and classical genetic approaches cannot be combined with molecular biological methods. Here, we show that CRISPR/Cas9 can be efficiently used for gene inactivation. Two genes of the melanin biosynthesis pathway, pksA and brm2, were chosen as targets. Several white mutants were obtained after several rounds of strain purification through protoplast regeneration or spore inoculation. Mutation of the genes was due to deletions from 1bp to 1.5kbp. The CRISPR/Cas9 system was also used to inactivate the orotidine-5-phosphate decarboxylase gene pyrG to create a uracil-auxotrophic strain. The strain was counter-selected with fluor-orotic acid and could be re-transformed with pyrG from Aspergillus fumigatus and pyr-4 from Neurospora crassa. In order to test the functioning of GFP, the fluorescent protein was fused to a nuclear localization signal derived from the StuA transcription factor of Aspergillus nidulans. After transformation bright nuclei were visible.
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Affiliation(s)
- Maximilian Wenderoth
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute for Applied Biosciences, Dept. of Microbiology, Fritz-Haber-Weg 4, D-76131 Karlsruhe, Germany
| | - Christoph Pinecker
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute for Applied Biosciences, Dept. of Microbiology, Fritz-Haber-Weg 4, D-76131 Karlsruhe, Germany
| | - Benjamin Voß
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute for Applied Biosciences, Dept. of Microbiology, Fritz-Haber-Weg 4, D-76131 Karlsruhe, Germany
| | - Reinhard Fischer
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute for Applied Biosciences, Dept. of Microbiology, Fritz-Haber-Weg 4, D-76131 Karlsruhe, Germany. http://www.iab.kit.de
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27
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Abstract
Melanins are ancient biological pigments found in all kingdoms of life. In fungi, their role in microbial pathogenesis is well established; however, these complex biomolecules also confer upon fungal microorganisms the faculty to tolerate extreme environments such as the Earth's poles, the International Space Station and places contaminated by toxic metals and ionizing radiation. A remarkable property of melanin is its capacity to interact with a wide range of electromagnetic radiation frequencies, functioning as a protecting and energy harvesting pigment. Other roles of fungal melanin include scavenging of free radical, thermo-tolerance, metal ion sequestration, cell development, and mechanical-chemical cellular strength. In this review, we explore the various functions ascribed to this biological pigment in fungi and its remarkable physicochemical properties.
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Affiliation(s)
- Radames JB Cordero
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205
| | - Arturo Casadevall
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205
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28
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Estiarte N, Lawrence C, Sanchis V, Ramos A, Crespo-Sempere A. LaeA and VeA are involved in growth morphology, asexual development, and mycotoxin production in Alternaria alternata. Int J Food Microbiol 2016; 238:153-164. [DOI: 10.1016/j.ijfoodmicro.2016.09.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Revised: 07/29/2016] [Accepted: 09/05/2016] [Indexed: 12/21/2022]
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29
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Barkal LJ, Theberge AB, Guo CJ, Spraker J, Rappert L, Berthier J, Brakke KA, Wang CCC, Beebe DJ, Keller NP, Berthier E. Microbial metabolomics in open microscale platforms. Nat Commun 2016; 7:10610. [PMID: 26842393 PMCID: PMC4742997 DOI: 10.1038/ncomms10610] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 01/04/2016] [Indexed: 01/04/2023] Open
Abstract
The microbial secondary metabolome encompasses great synthetic diversity, empowering microbes to tune their chemical responses to changing microenvironments. Traditional metabolomics methods are ill-equipped to probe a wide variety of environments or environmental dynamics. Here we introduce a class of microscale culture platforms to analyse chemical diversity of fungal and bacterial secondary metabolomes. By leveraging stable biphasic interfaces to integrate microculture with small molecule isolation via liquid–liquid extraction, we enable metabolomics-scale analysis using mass spectrometry. This platform facilitates exploration of culture microenvironments (including rare media typically inaccessible using established methods), unusual organic solvents for metabolite isolation and microbial mutants. Utilizing Aspergillus, a fungal genus known for its rich secondary metabolism, we characterize the effects of culture geometry and growth matrix on secondary metabolism, highlighting the potential use of microscale systems to unlock unknown or cryptic secondary metabolites for natural products discovery. Finally, we demonstrate the potential for this class of microfluidic systems to study interkingdom communication between fungi and bacteria. Traditional methods for microbial culture and subsequent metabolomics are time-consuming and labour-intensive. Here the authors present a microscale culture platform with integrated extraction for efficient, low-volume metabolomics of relevant microenvironments and microbial co-cultures.
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Affiliation(s)
- Layla J Barkal
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA.,Carbone Cancer Center, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA
| | - Ashleigh B Theberge
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA.,Carbone Cancer Center, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA.,Department of Urology, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA
| | - Chun-Jun Guo
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Los Angeles California 90089, USA
| | - Joe Spraker
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA
| | - Lucas Rappert
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA
| | - Jean Berthier
- Department of Biotechnology, CEA-University Grenoble-Alpes, 17 Avenue des Martyrs, 38054 Grenoble, France
| | - Kenneth A Brakke
- Department of Mathematics, Susquehanna University, Selinsgrove, Pennsylvania 17870, USA
| | - Clay C C Wang
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Los Angeles California 90089, USA.,Department of Chemistry, University of Southern California, Los Angeles California 90089, USA
| | - David J Beebe
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA.,Carbone Cancer Center, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA
| | - Nancy P Keller
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA.,Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA
| | - Erwin Berthier
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA.,Carbone Cancer Center, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA
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30
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Schumacher J. DHN melanin biosynthesis in the plant pathogenic fungusBotrytis cinereais based on two developmentally regulated key enzyme (PKS)-encoding genes. Mol Microbiol 2015; 99:729-48. [DOI: 10.1111/mmi.13262] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/28/2015] [Indexed: 12/28/2022]
Affiliation(s)
- Julia Schumacher
- Institut für Biologie und Biotechnologie der Pflanzen (IBBP); Westfälische Wilhelms-Universität (WWU) Münster; Schlossplatz 8 48143 Münster Germany
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