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Yu Y, Li X, Hou Y, Wei M, Qian Y, Zhou Y, Yin M, Jiang Y, Song P. The effect of Ca 2+-calcineurin signaling pathway on the antifungal activity of Pd-D-V against Botrytis cinerea. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2024; 203:106007. [PMID: 39084802 DOI: 10.1016/j.pestbp.2024.106007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2024] [Revised: 06/26/2024] [Accepted: 06/29/2024] [Indexed: 08/02/2024]
Abstract
Gray mold, caused by Botrytis cinerea is an intractable fungal disease that causes extensive damage to agricultural products. In the search for novel antifungal active ingredients, we discovered a linear pyranocoumarin Pd-D-V was effective against B. cinerea in both in vitro and in vivo assays. Furthermore, this study investigated the effects of Ca2+ and the Ca2+-calcineurin signaling pathway on its antifungal activity against B. cinerea. The results indicated that Pd-D-V reduced the concentration of Ca2+ in the mycelia of B. cinerea; CaCl2, the Ca2+ channel blocker verapamil, or the calcineurin inhibitor cyclosporin A could affect the sensitivity of Pd-D-V against B. cinerea; the expression of genes (Bccch1, Bcmid1, BccnA, Bccnb1, Bcpmc1, and Bcpmr1) of the Ca2+-calcineurin signaling pathway decreased after Pd-D-V treatment. In summary, Pd-D-V is compound for developing fungicides against B. cinerea. Pd-D-V can reduce intracellular Ca2+ concentration and disturb Ca2+ homeostasis. The Ca2+-calcineurin signaling pathway is important in the antifungal activity of Pd-D-V against B. cinerea.
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Affiliation(s)
- Yao Yu
- Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Nanjing 210014, China
| | - Xinru Li
- Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Yiping Hou
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
| | - Min Wei
- Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Nanjing 210014, China
| | - Yiyun Qian
- Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Nanjing 210014, China
| | - Yuxin Zhou
- Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Nanjing 210014, China
| | - Min Yin
- Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Nanjing 210014, China
| | - Yanqin Jiang
- Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Nanjing 210014, China
| | - Pingping Song
- Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Nanjing 210014, China; Nanjing University of Chinese Medicine, Nanjing 210023, China.
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Escaray FJ, Felipo-Benavent A, Antonelli CJ, Balaguer B, Lopez-Gresa MP, Vera P. Plant triterpenoid saponins function as susceptibility factors to promote the pathogenicity of Botrytis cinerea. MOLECULAR PLANT 2024; 17:1073-1089. [PMID: 38807367 DOI: 10.1016/j.molp.2024.05.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 02/12/2024] [Accepted: 05/27/2024] [Indexed: 05/30/2024]
Abstract
The gray mold fungus Botrytis cinerea is a necrotrophic pathogen that causes diseases in hundreds of plant species, including high-value crops. Its polyxenous nature and pathogenic success are due to its ability to perceive host signals in its favor. In this study, we found that laticifer cells of Euphorbia lathyris are a source of susceptibility factors required by B. cinerea to cause disease. Consequently, poor-in-latex (pil) mutants, which lack laticifer cells, show full resistance to this pathogen, whereas lot-of-latex mutants, which produce more laticifer cells, are hypersusceptible. These S factors are triterpenoid saponins, which are widely distributed natural products of vast structural diversity. The downregulation of laticifer-specific oxydosqualene cyclase genes, which encode the first committed step enzymes for triterpene and, therefore, saponin biosynthesis, conferred disease resistance to B. cinerea. Likewise, the Medicago truncatula lha-1 mutant, compromised in triterpenoid saponin biosynthesis, showed enhanced resistance. Interestingly, the application of different purified triterpenoid saponins pharmacologically complemented the disease-resistant phenotype of pil and hla-1 mutants and enhanced disease susceptibility in different plant species. We found that triterpenoid saponins function as plant cues that signal transcriptional reprogramming in B. cinerea, leading to a change in its growth habit and infection strategy, culminating in the abundant formation of infection cushions, the multicellular appressoria apparatus dedicated to plant penetration and biomass destruction in B. cinerea. Taken together, these results provide an explanation for how plant triterpenoid saponins function as disease susceptibility factors to promote B. cinerea pathogenicity.
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Affiliation(s)
- Francisco J Escaray
- Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-C.S.I.C, Ciudad Politécnica de la Innovación, Edificio 8E, acceso G, Ingeniero Fausto Elio, s/n, 46022 Valencia, Spain
| | - Amelia Felipo-Benavent
- Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-C.S.I.C, Ciudad Politécnica de la Innovación, Edificio 8E, acceso G, Ingeniero Fausto Elio, s/n, 46022 Valencia, Spain
| | - Cristian J Antonelli
- Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-C.S.I.C, Ciudad Politécnica de la Innovación, Edificio 8E, acceso G, Ingeniero Fausto Elio, s/n, 46022 Valencia, Spain
| | - Begoña Balaguer
- Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-C.S.I.C, Ciudad Politécnica de la Innovación, Edificio 8E, acceso G, Ingeniero Fausto Elio, s/n, 46022 Valencia, Spain
| | - Maria Pilar Lopez-Gresa
- Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-C.S.I.C, Ciudad Politécnica de la Innovación, Edificio 8E, acceso G, Ingeniero Fausto Elio, s/n, 46022 Valencia, Spain
| | - Pablo Vera
- Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-C.S.I.C, Ciudad Politécnica de la Innovación, Edificio 8E, acceso G, Ingeniero Fausto Elio, s/n, 46022 Valencia, Spain.
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Wang H, Gai Y, Zhao Y, Wang M, Ma Z. The calcium-calcineurin and high-osmolarity glycerol pathways co-regulate tebuconazole sensitivity and pathogenicity in Fusarium graminearum. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2023; 190:105311. [PMID: 36740345 DOI: 10.1016/j.pestbp.2022.105311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 11/25/2022] [Accepted: 11/29/2022] [Indexed: 06/18/2023]
Abstract
The calcium-calcineurin and high-osmolarity glycerol (HOG) pathways play crucial roles in fungal development, pathogenicity, and in responses to various environmental stresses. However, interaction of these pathways in regulating fungicide sensitivity remains largely unknown in phytopathogenic fungi. In this study, we investigated the function of the calcium-calcineurin signalling pathway in Fusarium graminearum, the causal agent of Fusarium head blight. Inhibitors of Ca2+ and calcineurin enhanced antifungal activity of tebuconazole (an azole fungicide) against F. graminearum. Deletion of the putative downstream transcription factor FgCrz1 resulted in significantly increased sensitivity of F. graminearum to tebuconazole. FgCrz1-GFP was translocated to the nucleus upon tebuconazole treatment in a calcineurin-dependent manner. In addition, deletion of FgCrz1 increased the phosphorylation of FgHog1 in response to tebuconazole. Moreover, the calcium-calcineurin and HOG signalling pathways exhibited synergistic effect in regulating pathogenicity and sensitivity of F. graminearum to tebuconazole and multiple other stresses. RNA-seq data revealed that FgCrz1 regulated expression of a set of non-CYP51 genes that are associated with tebuconazole sensitivity, including multidrug transporters, membrane lipid biosynthesis and metabolism, and cell wall organization. Our findings demonstrate that the calcium-calcineurin and HOG pathways act coordinately to orchestrate tebuconazole sensitivity and pathogenicity in F. graminearum, which may provide novel insights in management of Fusarium disease.
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Affiliation(s)
- Huiyuan Wang
- State Key Laboratory of Rice Biology, Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Yunpeng Gai
- School of Grassland Science, Beijing Forestry University, Beijing 100083, China
| | - Youfu Zhao
- Irrigated Agriculture Research and Extension Center, Department of Plant Pathology, Washington State University, Prosser, WA 99350, USA
| | - Minhui Wang
- State Key Laboratory of Rice Biology, Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China.
| | - Zhonghua Ma
- State Key Laboratory of Rice Biology, Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China
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4
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Song PP, Wang Y, Hou YP, Mao XW, Liu ZL, Wei M, Yu JP, Wang B, Qian YY, Yan L, Xu S, Jiang YQ, Zhou DQ, Yin M, Dou J. Crucial role of Ca 2+ /CN signalling pathway in the antifungal activity of disenecioyl-cis-khellactone against Botrytis cinerea. PEST MANAGEMENT SCIENCE 2022; 78:4649-4659. [PMID: 35866518 DOI: 10.1002/ps.7085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 06/21/2022] [Accepted: 07/22/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND Botrytis cinerea causes grey mould and is one of the most destructive fungal pathogens affecting important fruit and vegetable crops. In preliminary studies, we found that disenecioyl-cis-khellactone (DK) had strong antifungal activity against several fungi species including B. cinerea [half maximal effective concentration (EC50 ) = 11.0 μg mL-1 ]. In this study, we aimed to further evaluate the antifungal activity of DK against B. cinerea and determine the role of calcium ion/calcineurin (Ca2+ /CN) signalling pathway on its antifungal effect. RESULTS DK was effective against B. cinerea in both in vitro and in vivo assays. Exogenous Ca2+ reduced the antifungal activity of DK. The combination of DK and cyclosporine A (CsA) did not exhibit an additive effect against B. cinerea. In contrast to CsA, DK reduced the intracellular Ca2+ concentration in B. cinerea. DK bound to calcineurin A (cnA) and up-regulated the expression of PMC1 and PMR1 genes. Moreover, DK sensitivity of △bccnA significantly decreased compared with that of Bc05.10 strain. CONCLUSION DK is a promising lead compound for developing fungicides against B. cinerea. The Ca2+ /CN signalling pathway plays a crucial role in the DK antifungal activity, and cnA is one of the targets of DK against B. cinerea. DK directly reacts with cnA, which up-regulates the transcription of Ca2+ /CN-dependent target genes PMC1 and PMR1, decreasing the intracellular Ca2+ concentration and disturbing the intracellular Ca2+ balance, leading to cell death. © 2022 Society of Chemical Industry.
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Affiliation(s)
- Ping-Ping Song
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing, China
| | - Yu Wang
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing, China
| | - Yi-Ping Hou
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Xue-Wei Mao
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Zong-Liang Liu
- Yantai University, School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Centre of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai, China
| | - Min Wei
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing, China
| | - Jin-Ping Yu
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing, China
| | - Bi Wang
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing, China
| | - Yi-Yun Qian
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing, China
| | - Lu Yan
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing, China
| | - Shu Xu
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing, China
| | - Yan-Qin Jiang
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing, China
| | - Dong-Qin Zhou
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing, China
| | - Min Yin
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing, China
| | - Jian Dou
- Institute of Botany, Jiangsu Province and Chinese Academy of Sciences, Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing, China
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Anta-Fernández F, Santander-Gordón D, Becerra S, Santamaría R, Díaz-Mínguez JM, Benito EP. Nitric Oxide Metabolism Affects Germination in Botrytis cinerea and Is Connected to Nitrate Assimilation. J Fungi (Basel) 2022; 8:jof8070699. [PMID: 35887455 PMCID: PMC9324006 DOI: 10.3390/jof8070699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 06/29/2022] [Accepted: 06/30/2022] [Indexed: 11/16/2022] Open
Abstract
Nitric oxide regulates numerous physiological processes in species from all taxonomic groups. Here, its role in the early developmental stages of the fungal necrotroph Botrytis cinerea was investigated. Pharmacological analysis demonstrated that NO modulated germination, germ tube elongation and nuclear division rate. Experimental evidence indicates that exogenous NO exerts an immediate but transitory negative effect, slowing down germination-associated processes, and that this effect is largely dependent on the flavohemoglobin BCFHG1. The fungus exhibited a “biphasic response” to NO, being more sensitive to low and high concentrations than to intermediate levels of the NO donor. Global gene expression analysis in the wild-type and ΔBcfhg1 strains indicated a situation of strong nitrosative and oxidative stress determined by exogenous NO, which was much more intense in the mutant strain, that the cells tried to alleviate by upregulating several defense mechanisms, including the simultaneous upregulation of the genes encoding the flavohemoglobin BCFHG1, a nitronate monooxygenase (NMO) and a cyanide hydratase. Genetic evidence suggests the coordinated expression of Bcfhg1 and the NMO coding gene, both adjacent and divergently arranged, in response to NO. Nitrate assimilation genes were upregulated upon exposure to NO, and BCFHG1 appeared to be the main enzymatic system involved in the generation of the signal triggering their induction. Comparative expression analysis also showed the influence of NO on other cellular processes, such as mitochondrial respiration or primary and secondary metabolism, whose response could have been mediated by NmrA-like domain proteins.
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Affiliation(s)
- Francisco Anta-Fernández
- Institute for Agribiotechnology Research (CIALE), Department of Microbiology and Genetics, University of Salamanca, 37008 Salamanca, Spain; (F.A.-F.); (S.B.); (J.M.D.-M.)
| | - Daniela Santander-Gordón
- Facultad de Ingeniería y Ciencias Aplicadas (FICA), Carrera de Ingeniería en Biotecnología, Universidad de las Américas (UDLA), Quito 170513, Ecuador;
| | - Sioly Becerra
- Institute for Agribiotechnology Research (CIALE), Department of Microbiology and Genetics, University of Salamanca, 37008 Salamanca, Spain; (F.A.-F.); (S.B.); (J.M.D.-M.)
| | - Rodrigo Santamaría
- Department of Computer Science, University of Salamanca, 37008 Salamanca, Spain;
| | - José María Díaz-Mínguez
- Institute for Agribiotechnology Research (CIALE), Department of Microbiology and Genetics, University of Salamanca, 37008 Salamanca, Spain; (F.A.-F.); (S.B.); (J.M.D.-M.)
| | - Ernesto Pérez Benito
- Institute for Agribiotechnology Research (CIALE), Department of Microbiology and Genetics, University of Salamanca, 37008 Salamanca, Spain; (F.A.-F.); (S.B.); (J.M.D.-M.)
- Correspondence:
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Liu C, Liu T, Lv Z, Qin M, Qu Z, Zhang Z, Li F, Chen D, Zhang X, Chen XL, Shen M. A Calcineurin Regulator MoRCN1 Is Important for Asexual Development, Stress Response, and Plant Infection of Magnaporthe oryzae. FRONTIERS IN PLANT SCIENCE 2022; 13:925645. [PMID: 35783935 PMCID: PMC9244802 DOI: 10.3389/fpls.2022.925645] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 05/05/2022] [Indexed: 06/12/2023]
Abstract
The calcium/calcineurin signaling pathway plays a key role in the development and virulence of plant pathogenic fungi, but the regulation of this signaling pathway is still not clear. In this study, we identified a calcineurin regulator MoRCN1 in the plant pathogenic fungus Magnaporthe oryzae and found it is important for virulence by regulating the calcineurin pathway. MoRCN1 deletion mutants were severely decreased in colony growth and conidia formation. More importantly, the deletion of MoRCN1 led to a significant reduction in virulence due to defects in appressorium formation and invasive growth. The ΔMorcn1 mutants were more sensitive to different stresses and induced host ROS accumulation, suggesting a role of MoRCN1 in stress adaptation. We found that MoRCN1 directly interacted with the calcineurin catalytic subunit MoCNA and affected its protein stability, which was therefore important for regulating the calcineurin pathway. Transcriptome analysis showed that MoRCN1 significantly activated 491 genes and suppressed 337 genes in response to calcium ion, partially overlapped with the MoCRZ1-bound genes. Gene Ontology and KEGG pathway analyses indicated that MoRCN1-regulated genes were enriched in stress adaptation, lipid metabolism, and secondary metabolite biosynthesis, reflecting a function of MoRCN1 in host cell adaptation. Altogether, these results suggest MoRCN1 functions as a regulator of the calcium/calcineurin signaling pathway for fungal development and infection of host cells.
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Affiliation(s)
- Caiyun Liu
- Hubei Key Laboratory of Economic Forest Germplasm Improvement and Resources Comprehensive Utilization, College of Biology and Agricultural Resources, Huanggang Normal University, Huanggang, China
- State Key Laboratory of Agricultural Microbiology and Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Tiangu Liu
- State Key Laboratory of Agricultural Microbiology and Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Ziwei Lv
- State Key Laboratory of Agricultural Microbiology and Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Mengyuan Qin
- State Key Laboratory of Agricultural Microbiology and Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Zhiguang Qu
- State Key Laboratory of Agricultural Microbiology and Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Ziwei Zhang
- State Key Laboratory of Agricultural Microbiology and Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Fuyan Li
- State Key Laboratory of Agricultural Microbiology and Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Deng Chen
- State Key Laboratory of Agricultural Microbiology and Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Xinrong Zhang
- State Key Laboratory of Agricultural Microbiology and Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Xiao-Lin Chen
- State Key Laboratory of Agricultural Microbiology and Provincial Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Mi Shen
- Hubei Key Laboratory of Economic Forest Germplasm Improvement and Resources Comprehensive Utilization, College of Biology and Agricultural Resources, Huanggang Normal University, Huanggang, China
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Cyclophilin BcCyp2 Regulates Infection-Related Development to Facilitate Virulence of the Gray Mold Fungus Botrytis cinerea. Int J Mol Sci 2021; 22:ijms22041694. [PMID: 33567582 PMCID: PMC7914984 DOI: 10.3390/ijms22041694] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 02/01/2021] [Accepted: 02/04/2021] [Indexed: 11/23/2022] Open
Abstract
Cyclophilin (Cyp) and Ca2+/calcineurin proteins are cellular components related to fungal morphogenesis and virulence; however, their roles in mediating the pathogenesis of Botrytis cinerea, the causative agent of gray mold on over 1000 plant species, remain largely unexplored. Here, we show that disruption of cyclophilin gene BcCYP2 did not impair the pathogen mycelial growth, osmotic and oxidative stress adaptation as well as cell wall integrity, but delayed conidial germination and germling development, altered conidial and sclerotial morphology, reduced infection cushion (IC) formation, sclerotial production and virulence. Exogenous cyclic adenosine monophosphate (cAMP) rescued the deficiency of IC formation of the ∆Bccyp2 mutants, and exogenous cyclosporine A (CsA), an inhibitor targeting cyclophilins, altered hyphal morphology and prevented host-cell penetration in the BcCYP2 harboring strains. Moreover, calcineurin-dependent (CND) genes are differentially expressed in strains losing BcCYP2 in the presence of CsA, suggesting that BcCyp2 functions in the upstream of cAMP- and Ca2+/calcineurin-dependent signaling pathways. Interestingly, during IC formation, expression of BcCYP2 is downregulated in a mutant losing BcJAR1, a gene encoding histone 3 lysine 4 (H3K4) demethylase that regulates fungal development and pathogenesis, in B. cinerea, implying that BcCyp2 functions under the control of BcJar1. Collectively, our findings provide new insights into cyclophilins mediating the pathogenesis of B. cinerea and potential targets for drug intervention for fungal diseases.
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Plaza V, Silva-Moreno E, Castillo L. Breakpoint: Cell Wall and Glycoproteins and their Crucial Role in the Phytopathogenic Fungi Infection. Curr Protein Pept Sci 2021; 21:227-244. [PMID: 31490745 DOI: 10.2174/1389203720666190906165111] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 08/02/2019] [Accepted: 08/17/2019] [Indexed: 01/09/2023]
Abstract
The cell wall that surrounds fungal cells is essential for their survival, provides protection against physical and chemical stresses, and plays relevant roles during infection. In general, the fungal cell wall is composed of an outer layer of glycoprotein and an inner skeletal layer of β-glucans or α- glucans and chitin. Chitin synthase genes have been shown to be important for septum formation, cell division and virulence. In the same way, chitin can act as a potent elicitor to activate defense response in several plant species; however, the fungi can convert chitin to chitosan during plant infection to evade plant defense mechanisms. Moreover, α-1,3-Glucan, a non-degradable polysaccharide in plants, represents a key feature in fungal cell walls formed in plants and plays a protective role for this fungus against plant lytic enzymes. A similar case is with β-1,3- and β-1,6-glucan which are essential for infection, structure rigidity and pathogenicity during fungal infection. Cell wall glycoproteins are also vital to fungi. They have been associated with conidial separation, the increase of chitin in conidial cell walls, germination, appressorium formation, as well as osmotic and cell wall stress and virulence; however, the specific roles of glycoproteins in filamentous fungi remain unknown. Fungi that can respond to environmental stimuli distinguish these signals and relay them through intracellular signaling pathways to change the cell wall composition. They play a crucial role in appressorium formation and penetration, and release cell wall degrading enzymes, which determine the outcome of the interaction with the host. In this review, we highlight the interaction of phypatophogen cell wall and signaling pathways with its host and their contribution to fungal pathogenesis.
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Affiliation(s)
- Verónica Plaza
- Laboratorio de Biología Molecular y Bioquímica, Departamento de Biología, Universidad de La Serena, La Serena, Chile
| | - Evelyn Silva-Moreno
- Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Temuco, Chile
| | - Luis Castillo
- Laboratorio de Biología Molecular y Bioquímica, Departamento de Biología, Universidad de La Serena, La Serena, Chile
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The Destructive Fungal Pathogen Botrytis cinerea-Insights from Genes Studied with Mutant Analysis. Pathogens 2020; 9:pathogens9110923. [PMID: 33171745 PMCID: PMC7695001 DOI: 10.3390/pathogens9110923] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 11/01/2020] [Accepted: 11/04/2020] [Indexed: 12/03/2022] Open
Abstract
Botrytis cinerea is one of the most destructive fungal pathogens affecting numerous plant hosts, including many important crop species. As a molecularly under-studied organism, its genome was only sequenced at the beginning of this century and it was recently updated with improved gene annotation and completeness. In this review, we summarize key molecular studies on B. cinerea developmental and pathogenesis processes, specifically on genes studied comprehensively with mutant analysis. Analyses of these studies have unveiled key genes in the biological processes of this pathogen, including hyphal growth, sclerotial formation, conidiation, pathogenicity and melanization. In addition, our synthesis has uncovered gaps in the present knowledge regarding development and virulence mechanisms. We hope this review will serve to enhance the knowledge of the biological mechanisms behind this notorious fungal pathogen.
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10
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Hou YH, Hsu LH, Wang HF, Lai YH, Chen YL. Calcineurin Regulates Conidiation, Chlamydospore Formation and Virulence in Fusarium oxysporum f. sp. lycopersici. Front Microbiol 2020; 11:539702. [PMID: 33193126 PMCID: PMC7641966 DOI: 10.3389/fmicb.2020.539702] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 09/25/2020] [Indexed: 11/24/2022] Open
Abstract
Fusarium wilt of tomato caused by the ascomycetous fungus Fusarium oxysporum f. sp. lycopersici (Fol) is widespread in most tomato planting areas. Calcineurin is a heterodimeric calcium/calmodulin-dependent protein phosphatase comprised of catalytic (Cna1) and regulatory (Cnb1) subunits. Calcineurin has been studied extensively in human fungal pathogens, but less is known about its roles in plant fungal pathogens. It is known that calcineurin regulates fungal calcium signaling, growth, drug tolerance, and virulence. However, the roles of calcineurin in Fol have not yet been characterized. In this study, we deleted calcineurin CNA1 and CNB1 genes to characterize their roles in conidiation, chlamydospore formation and virulence in Fol. Our results revealed that both cna1 and cnb1 mutants show defects in calcineurin phosphatase activity, vegetative growth and conidiation as compared to the wild type. Furthermore, calcineurin mutants exhibited blunted and swollen hyphae as observed by scanning electron microscopy. Interestingly, we found that Fol calcineurin is critical for chlamydospore formation, a function of calcineurin previously undocumented in the fungal kingdom. According to transcriptome analysis, the expression of 323 and 414 genes was up- and down-regulated, respectively, in both cna1 and cnb1 mutants. Based on the pathogen infection assay, tomato plants inoculated with cna1 or cnb1 mutant have a dramatic reduction in disease severity, indicating that calcineurin has a vital role in Fol virulence. In conclusion, our findings suggest that Fol calcineurin is required, at least in part, for phosphatase activity, vegetative growth, conidiation, chlamydospore formation, and virulence.
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Affiliation(s)
- Yi-Hsuan Hou
- Department of Plant Pathology and Microbiology, National Taiwan University, Taipei, Taiwan
| | - Li-Hang Hsu
- Department of Plant Pathology and Microbiology, National Taiwan University, Taipei, Taiwan
| | - Hsuan-Fu Wang
- Department of Plant Pathology and Microbiology, National Taiwan University, Taipei, Taiwan
| | - Yu-Hsin Lai
- Department of Plant Pathology and Microbiology, National Taiwan University, Taipei, Taiwan
| | - Ying-Lien Chen
- Department of Plant Pathology and Microbiology, National Taiwan University, Taipei, Taiwan
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Lin Y, Ruan H, Akutse KS, Lai B, Lin Y, Hou Y, Zhong F. Ethylene and Benzaldehyde Emitted from Postharvest Tomatoes Inhibit Botrytis cinerea via Binding to G-Protein Coupled Receptors and Transmitting with cAMP-Signal Pathway of the Fungus. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:13706-13717. [PMID: 31693347 DOI: 10.1021/acs.jafc.9b05778] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Tomato storage conditions are difficult largely due to Botrytis cinerea infection which causes gray mold disease. However, the effects of the volatile organic compounds (VOCs) emitted by postharvest tomatoes on this fungus remain unclear. We analyzed the effects of tomato-emitted VOCs on B. cinerea pathogenicity, germination, and hyphal growth with bioassay, predicted the causative active compounds by principle component analysis, identified G-protein-coupled receptors (GPCRs) which captured chemical signals in the B. cinerea genome by stimulating molecular docking, tested the binding affinities of these receptors for the active compounds by fluorescence binding competition assay, and identified an associated signaling pathway by RNA interfere. The VOCs emitted by postharvest tomatoes inhibited B. cinerea; ethylene and benzaldehyde were the active compounds causing this effect. One of the identified GPCRs in B. cinerea, BcGPR3, bound tightly to both active compounds. Two genes associated with the cAMP signaling pathway (BcRcn1 and BcCnA) were downregulated in wild-type B. cinerea exposed to the active compounds, as well as in the ΔBcgpr3 B. cinerea mutant. Exposure to postharvest tomato VOCs reduces B. cinerea pathogenicity due to ethylene and benzaldehyde volatiles. The BcGPR3 protein is inactivated by the active compounds, and thus fails to transmit signals to the cAMP pathway, thereby inhibiting B. cinerea.
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Affiliation(s)
- Yongwen Lin
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & College of Horticulture , Fujian Agriculture and Forestry University Fujian , 350013 Fuzhou , Fujian , P. R. China
| | - Hongchun Ruan
- Institute of Plant Protection , Fujian Academy of Agricultural Sciences , 350013 Fuzhou , Fujian , P. R. China
| | - Komivi Senyo Akutse
- International Centre of Insect Physiology and Ecology , 30772-00100 Nairobi , Kenya
| | - Baochun Lai
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & College of Horticulture , Fujian Agriculture and Forestry University Fujian , 350013 Fuzhou , Fujian , P. R. China
| | - Yizhang Lin
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & College of Horticulture , Fujian Agriculture and Forestry University Fujian , 350013 Fuzhou , Fujian , P. R. China
| | - Youming Hou
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & College of Horticulture , Fujian Agriculture and Forestry University Fujian , 350013 Fuzhou , Fujian , P. R. China
| | - Fenglin Zhong
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & College of Horticulture , Fujian Agriculture and Forestry University Fujian , 350013 Fuzhou , Fujian , P. R. China
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Proteomic study of the membrane components of signalling cascades of Botrytis cinerea controlled by phosphorylation. Sci Rep 2019; 9:9860. [PMID: 31285484 PMCID: PMC6614480 DOI: 10.1038/s41598-019-46270-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 06/26/2019] [Indexed: 12/19/2022] Open
Abstract
Protein phosphorylation and membrane proteins play an important role in the infection of plants by phytopathogenic fungi, given their involvement in signal transduction cascades. Botrytis cinerea is a well-studied necrotrophic fungus taken as a model organism in fungal plant pathology, given its broad host range and adverse economic impact. To elucidate relevant events during infection, several proteomics analyses have been performed in B. cinerea, but they cover only 10% of the total proteins predicted in the genome database of this fungus. To increase coverage, we analysed by LC-MS/MS the first-reported overlapped proteome in phytopathogenic fungi, the "phosphomembranome" of B. cinerea, combining the two most important signal transduction subproteomes. Of the 1112 membrane-associated phosphoproteins identified, 64 and 243 were classified as exclusively identified or overexpressed under glucose and deproteinized tomato cell wall conditions, respectively. Seven proteins were found under both conditions, but these presented a specific phosphorylation pattern, so they were considered as exclusively identified or overexpressed proteins. From bioinformatics analysis, those differences in the membrane-associated phosphoproteins composition were associated with various processes, including pyruvate metabolism, unfolded protein response, oxidative stress response, autophagy and cell death. Our results suggest these proteins play a significant role in the B. cinerea pathogenic cycle.
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Mitic M, Berry D, Brasell E, Green K, Young CA, Saikia S, Rakonjac J, Scott B. Disruption of calcineurin catalytic subunit (cnaA) in Epichloë festucae induces symbiotic defects and intrahyphal hyphae formation. MOLECULAR PLANT PATHOLOGY 2018; 19:1414-1426. [PMID: 28990722 PMCID: PMC6638138 DOI: 10.1111/mpp.12624] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 10/03/2017] [Accepted: 10/04/2017] [Indexed: 05/30/2023]
Abstract
Calcineurin is a conserved calcium/calmodulin-dependent protein phosphatase, consisting of a catalytic subunit A and a regulatory subunit B, which is involved in calcium-dependent signalling and regulation of various important cellular processes. In this study, we functionally characterized the catalytic subunit A (CnaA) of the endophytic fungus Epichloë festucae which forms a symbiotic association with the grass host Lolium perenne. We deleted the CnaA-encoding gene cnaA in E. festucae and examined its role in hyphal growth, cell wall integrity and symbiosis. This ΔcnaA strain had a severe growth defect with loss of radial growth and hyper-branched hyphae. Transmission electron microscopy and confocal microscopy analysis of the mutant revealed cell wall defects, aberrant septation and the formation of intrahyphal hyphae, both in culture and in planta. The mutant strain also showed a reduced infection rate in planta. The fluorescence of mutant hyphae stained with WGA-AF488 was reduced, indicating reduced chitin accessibility. Together, these results show that E. festucae CnaA is required for fungal growth, maintaining cell wall integrity and host colonization.
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Affiliation(s)
- Milena Mitic
- Institute of Fundamental Sciences, Massey UniversityPalmerston North4442New Zealand
- BioProtection Research Centre, Massey UniversityPalmerston North4442New Zealand
| | - Daniel Berry
- Institute of Fundamental Sciences, Massey UniversityPalmerston North4442New Zealand
| | - Emma Brasell
- Institute of Fundamental Sciences, Massey UniversityPalmerston North4442New Zealand
| | - Kimberly Green
- Institute of Fundamental Sciences, Massey UniversityPalmerston North4442New Zealand
- BioProtection Research Centre, Massey UniversityPalmerston North4442New Zealand
| | | | - Sanjay Saikia
- Institute of Fundamental Sciences, Massey UniversityPalmerston North4442New Zealand
| | - Jasna Rakonjac
- Institute of Fundamental Sciences, Massey UniversityPalmerston North4442New Zealand
| | - Barry Scott
- Institute of Fundamental Sciences, Massey UniversityPalmerston North4442New Zealand
- BioProtection Research Centre, Massey UniversityPalmerston North4442New Zealand
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Liu J, Sui Y, Chen H, Liu Y, Liu Y. Proteomic Analysis of Kiwifruit in Response to the Postharvest Pathogen, Botrytis cinerea. FRONTIERS IN PLANT SCIENCE 2018; 9:158. [PMID: 29497428 PMCID: PMC5818428 DOI: 10.3389/fpls.2018.00158] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 01/29/2018] [Indexed: 05/29/2023]
Abstract
Gray mold, caused by the fungus Botrytis cinerea, is the most significant postharvest disease of kiwifruit. In the present study, iTRAQ with LC-ESI-MS/MS was used to identify the kiwifruit proteins associated with the response to B. cinerea. A total of 2,487 proteins in kiwifruit were identified. Among them, 292 represented differentially accumulated proteins (DAPs), with 196 DAPs having increased, and 96 DAPs having decreased in accumulation in B. cinerea-inoculated vs. water-inoculated, control kiwifruits. DAPs were associated with penetration site reorganization, cell wall degradation, MAPK cascades, ROS signaling, and PR proteins. In order to examine the corresponding transcriptional levels of the DAPs, RT-qPCR was conducted on a subset of 9 DAPs. In addition, virus-induced gene silencing was used to examine the role of myosin 10 in kiwifruit, a gene modulating host penetration resistance to fungal infection, in response to B. cinerea infection. The present study provides new insight on the understanding of the interaction between kiwifruit and B. cinerea.
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Affiliation(s)
- Jia Liu
- Chongqing Key Laboratory of Economic Plant Biotechnology, Collaborative Innovation Centre of Special Plant Industry in Chongqing, College of Forestry and Life Science, Institute of Special Plants, Chongqing University of Arts and Sciences, Yongchuan, China
| | - Yuan Sui
- Chongqing Key Laboratory of Economic Plant Biotechnology, Collaborative Innovation Centre of Special Plant Industry in Chongqing, College of Forestry and Life Science, Institute of Special Plants, Chongqing University of Arts and Sciences, Yongchuan, China
| | - Huizhen Chen
- College of Food Science and Engineering, Hefei University of Technology, Hefei, China
- College of Biology Science and Engineering, Hebei University of Economics and Business, Shijiazhuang, China
| | - Yiqing Liu
- Chongqing Key Laboratory of Economic Plant Biotechnology, Collaborative Innovation Centre of Special Plant Industry in Chongqing, College of Forestry and Life Science, Institute of Special Plants, Chongqing University of Arts and Sciences, Yongchuan, China
| | - Yongsheng Liu
- College of Food Science and Engineering, Hefei University of Technology, Hefei, China
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Rodenburg SYA, Terhem RB, Veloso J, Stassen JHM, van Kan JAL. Functional Analysis of Mating Type Genes and Transcriptome Analysis during Fruiting Body Development of Botrytis cinerea. mBio 2018; 9:e01939-17. [PMID: 29440571 PMCID: PMC5821092 DOI: 10.1128/mbio.01939-17] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 01/17/2018] [Indexed: 02/07/2023] Open
Abstract
Botrytis cinerea is a plant-pathogenic fungus producing apothecia as sexual fruiting bodies. To study the function of mating type (MAT) genes, single-gene deletion mutants were generated in both genes of the MAT1-1 locus and both genes of the MAT1-2 locus. Deletion mutants in two MAT genes were entirely sterile, while mutants in the other two MAT genes were able to develop stipes but never formed an apothecial disk. Little was known about the reprogramming of gene expression during apothecium development. We analyzed transcriptomes of sclerotia, three stages of apothecium development (primordia, stipes, and apothecial disks), and ascospores by RNA sequencing. Ten secondary metabolite gene clusters were upregulated at the onset of sexual development and downregulated in ascospores released from apothecia. Notably, more than 3,900 genes were differentially expressed in ascospores compared to mature apothecial disks. Among the genes that were upregulated in ascospores were numerous genes encoding virulence factors, which reveals that ascospores are transcriptionally primed for infection prior to their arrival on a host plant. Strikingly, the massive transcriptional changes at the initiation and completion of the sexual cycle often affected clusters of genes, rather than randomly dispersed genes. Thirty-five clusters of genes were jointly upregulated during the onset of sexual reproduction, while 99 clusters of genes (comprising >900 genes) were jointly downregulated in ascospores. These transcriptional changes coincided with changes in expression of genes encoding enzymes participating in chromatin organization, hinting at the occurrence of massive epigenetic regulation of gene expression during sexual reproduction.IMPORTANCE Fungal fruiting bodies are formed by sexual reproduction. We studied the development of fruiting bodies ("apothecia") of the ubiquitous plant-pathogenic ascomycete Botrytis cinerea The role of mating type genes in apothecium development was investigated by targeted mutation. Two genes are essential for the initiation of sexual development; mutants in these genes are sterile. Two other genes were not essential for development of stipes; however, they were essential for stipes to develop a disk and produce sexual ascospores. We examined gene expression profiles during apothecium development, as well as in ascospores sampled from apothecia. We provide the first study ever of the transcriptome of pure ascospores in a filamentous fungus. The expression of numerous genes involved in plant infection was induced in the ascospores, implying that ascospores are developmentally primed for infection before their release from apothecia.
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Affiliation(s)
- Sander Y A Rodenburg
- Laboratory of Phytopathology, Wageningen University, Wageningen, The Netherlands
- Wageningen University, Bioinformatics Group, Wageningen, The Netherlands
| | - Razak B Terhem
- Laboratory of Phytopathology, Wageningen University, Wageningen, The Netherlands
| | - Javier Veloso
- Laboratory of Phytopathology, Wageningen University, Wageningen, The Netherlands
- Department of Plant Physiology, Faculty of Sciences, University of A Coruña, A Coruña, Spain
| | - Joost H M Stassen
- Laboratory of Phytopathology, Wageningen University, Wageningen, The Netherlands
| | - Jan A L van Kan
- Laboratory of Phytopathology, Wageningen University, Wageningen, The Netherlands
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17
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Marschall R, Tudzynski P. The Protein Disulfide Isomerase of Botrytis cinerea: An ER Protein Involved in Protein Folding and Redox Homeostasis Influences NADPH Oxidase Signaling Processes. Front Microbiol 2017; 8:960. [PMID: 28611757 PMCID: PMC5447010 DOI: 10.3389/fmicb.2017.00960] [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: 02/24/2017] [Accepted: 05/15/2017] [Indexed: 11/13/2022] Open
Abstract
Botrytis cinerea is a filamentous plant pathogen, which infects hundreds of plant species; within its lifestyle, the production of reactive oxygen species (ROS) and a balanced redox homeostasis are essential parameters. The pathogen is capable of coping with the plant’s oxidative burst and even produces its own ROS to enhance the plant’s oxidative burst. Highly conserved NADPH oxidase (Nox) complexes produce the reactive molecules. The membrane-associated complexes regulate a large variety of vegetative and pathogenic processes. Besides their commonly accepted function at the plasma membrane, recent studies reveal that Nox complexes are also active at the membrane of the endoplasmic reticulum. In this study, we identified the essential ER protein BcPdi1 as new interaction partner of the NoxA complex in B. cinerea. Mutants that lack this ER chaperone display overlapping phenotypes to mutants of the NoxA signaling pathway. The protein appears to be involved in all major developmental processes, such as the formation of sclerotia, conidial anastomosis tubes and infection cushions (IC’s) and is needed for full virulence. Moreover, expression analyses and reporter gene studies indicate that BcPdi1 affects the redox homeostasis and unfolded protein response (UPR)-related genes. Besides the close association between BcPdi1 and BcNoxA, interaction studies provide evidence that the ER protein might likewise be involved in Ca2+ regulated processes. Finally, we were able to show that the potential key functions of the protein BcPdi1 might be affected by its phosphorylation state.
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Affiliation(s)
- Robert Marschall
- Institut für Biologie und Biotechnologie der Pflanzen, Westfälische Wilhelms-Universität MünsterMünster, Germany
| | - Paul Tudzynski
- Institut für Biologie und Biotechnologie der Pflanzen, Westfälische Wilhelms-Universität MünsterMünster, Germany
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González-Rodríguez VE, Garrido C, Cantoral JM, Schumacher J. The F-actin capping protein is required for hyphal growth and full virulence but is dispensable for septum formation in Botrytis cinerea. Fungal Biol 2016; 120:1225-35. [PMID: 27647239 DOI: 10.1016/j.funbio.2016.07.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Revised: 07/05/2016] [Accepted: 07/07/2016] [Indexed: 01/20/2023]
Abstract
Filamentous (F-) actin is an integral part of the cytoskeleton allowing for cell growth, intracellular motility, and cytokinesis of eukaryotic cells. Its assembly from G-actin monomers and its disassembly are tightly regulated processes involving a number of actin-binding proteins (ABPs) such as F-actin nucleators and cross-linking proteins. F-actin capping protein (CP) is an alpha/beta heterodimer known from yeast and higher eukaryotes to bind to the fast growing ends of the actin filaments stabilizing them. In this study, we identified the orthologs of the two CP subunits, named BcCPA1 and BcCPB1, in the plant pathogenic fungus Botrytis cinerea and showed that the two proteins physically interact in a yeast two-hybrid approach. GFP-BcCPA1 fusion proteins were functional and localized to the assumed sites of F-actin accumulation, i.e. to the hyphal tips and the sites of actin ring formation. Deletion of bccpa1 had a profound effect on hyphal growth, morphogenesis, and virulence indicating the importance of F-actin capping for an intact actin cytoskeleton. As polarized growth - unlike septum formation - is impaired in the mutants, it can be concluded that the organization and/or localization of actin patches and cables are disturbed rather than the functionality of the actin rings.
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Affiliation(s)
- Victoria E González-Rodríguez
- Departamento de Biomedicina, Biotecnología y Salud Pública, Laboratorio de Microbiología, Facultad de Ciencias de Mar y Ambientales, Instituto Universitario de Investigación Vitivinícola y Agroalimentaria (IVAGRO), Universidad de Cádiz, Polígono Río San Pedro, 11510 Puerto Real, Spain.
| | - Carlos Garrido
- Departamento de Biomedicina, Biotecnología y Salud Pública, Laboratorio de Microbiología, Facultad de Ciencias de Mar y Ambientales, Instituto Universitario de Investigación Vitivinícola y Agroalimentaria (IVAGRO), Universidad de Cádiz, Polígono Río San Pedro, 11510 Puerto Real, Spain.
| | - Jesús M Cantoral
- Departamento de Biomedicina, Biotecnología y Salud Pública, Laboratorio de Microbiología, Facultad de Ciencias de Mar y Ambientales, Instituto Universitario de Investigación Vitivinícola y Agroalimentaria (IVAGRO), Universidad de Cádiz, Polígono Río San Pedro, 11510 Puerto Real, Spain.
| | - Julia Schumacher
- Institut für Biologie und Biotechnologie der Pflanzen (IBBP), Westfälische Wilhelms-Universität Münster, Schlossplatz 8, 48143 Münster, Germany.
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Belmondo S, Marschall R, Tudzynski P, López Ráez JA, Artuso E, Prandi C, Lanfranco L. Identification of genes involved in fungal responses to strigolactones using mutants from fungal pathogens. Curr Genet 2016; 63:201-213. [DOI: 10.1007/s00294-016-0626-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 06/20/2016] [Accepted: 06/21/2016] [Indexed: 11/30/2022]
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Cetz-Chel JE, Balcázar-López E, Esquivel-Naranjo EU, Herrera-Estrella A. The Trichoderma atroviride putative transcription factor Blu7 controls light responsiveness and tolerance. BMC Genomics 2016; 17:327. [PMID: 27142227 PMCID: PMC4855978 DOI: 10.1186/s12864-016-2639-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 04/22/2016] [Indexed: 11/23/2022] Open
Abstract
Background Most living organisms use sunlight as a source of energy and/or information about their environment. Consequently, they have developed mechanisms to sense light quality and quantity. In the fungus Trichoderma atroviride blue-light is perceived through the Blue Light Regulator Complex, which in turn up-regulates a set of genes (blu) and down-regulates another set (bld), triggering asexual reproduction. To gain insight into this process, we characterized the blu7 gene, which encodes a protein containing a C2H2 zinc finger domain. Results Δblu7 mutants show reduced conidiation at low light fluences, which is still clear even when exposed to saturating light. For the first time we show a genome wide survey of light regulated gene expression in T. atroviride, including RNA-seq analyses of the wild type and the Δblu7 strains after brief exposure to blue-light. Our data show a reduction in the number of induced genes and an increase in down-regulated genes in the mutant. Light activates stress responses and several metabolic processes in the wild type strain that are no longer activated in the mutant. In agreement with the misregulation of metabolic processes, continuous exposure to white light strongly inhibited growth of the ∆blu7 mutant, in a carbon source dependent fashion. RNA-seq analyses under constant white light using glucose as sole carbon source revealed that localization and transport process present the opposite regulation pattern in the ∆blu7 and wild type strains. Genes related to amino acid, sugar and general transporters were enriched in the induced genes in the mutant and the repressed genes of the wild type. Peptone supplemented in the media restored growth of the ∆blu7 mutant in constant light, suggesting a role of Blu7 in the regulation of nitrogen metabolism in the presence of light. Conclusions Blu7 appears to regulate light sensitivity in terms of induction of conidiation, and to play a major role in supporting growth under continuous exposure to light. The diminished conidiation observed in ∆blu7 mutants is likely due to misregulation of the cAMP signaling pathway and ROS production, whereas their low tolerance to continuous exposure to light indicates that Blu7 is required for adaptation. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-2639-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- José E Cetz-Chel
- Laboratorio Nacional de Genómica para la Biodiversidad, CINVESTAV Sede Irapuato, Km 9.6 Libramiento Norte Carretera Irapuato-León, 36821, Irapuato, Guanajuato, Mexico
| | - Edgar Balcázar-López
- Laboratorio Nacional de Genómica para la Biodiversidad, CINVESTAV Sede Irapuato, Km 9.6 Libramiento Norte Carretera Irapuato-León, 36821, Irapuato, Guanajuato, Mexico
| | - Edgardo U Esquivel-Naranjo
- Laboratorio Nacional de Genómica para la Biodiversidad, CINVESTAV Sede Irapuato, Km 9.6 Libramiento Norte Carretera Irapuato-León, 36821, Irapuato, Guanajuato, Mexico.,Present Address: Unit for Basic and Applied Microbiology, Faculty of Natural Sciences, Autonomous University of Querétaro, Querétaro, 76230, Mexico
| | - Alfredo Herrera-Estrella
- Laboratorio Nacional de Genómica para la Biodiversidad, CINVESTAV Sede Irapuato, Km 9.6 Libramiento Norte Carretera Irapuato-León, 36821, Irapuato, Guanajuato, Mexico.
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Sasanuma I, Suzuki T. Effect of calcium on cell-wall degrading enzymes of Botrytis cinerea. Biosci Biotechnol Biochem 2016; 80:1730-6. [PMID: 26998660 DOI: 10.1080/09168451.2016.1146064] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Effective anti-Botrytis strategies leading to reduce pesticides on strawberries are examined to provide the protection that is harmless to humans, higher animals and plants. Calcium treatments significantly inhibited the spore germination and mycelial growth of B. cinerea. The intracellular polygalacturonase and CMCase showed low activities in B. cinerea cultivated by medium containing calcium. On the other hand, calcium-stimulated β-glucosidases production occurred. Our findings suggest that the calcium treatments keep CMCase activity low and cause low activities of cell-wall degrading enzymes of B. cinerea in the late stage of growth.
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Affiliation(s)
- Izumi Sasanuma
- a Department of Materials Chemistry and Bioengineering, National Institute of Technology , Oyama College , Oyama , Japan
| | - Takuya Suzuki
- a Department of Materials Chemistry and Bioengineering, National Institute of Technology , Oyama College , Oyama , Japan
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Chasing stress signals - Exposure to extracellular stimuli differentially affects the redox state of cell compartments in the wild type and signaling mutants of Botrytis cinerea. Fungal Genet Biol 2016; 90:12-22. [PMID: 26988904 DOI: 10.1016/j.fgb.2016.03.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 02/26/2016] [Accepted: 03/13/2016] [Indexed: 10/22/2022]
Abstract
Reactive oxygen species (ROS) are important molecules influencing intracellular developmental processes as well as plant pathogen interactions. They are produced at the infection site and affect the intracellular redox homeostasis. However, knowledge of ROS signaling pathways, their connection to other signaling cascades, and tools for the visualization of intra- and extracellular ROS levels and their impact on the redox state are scarce. By using the genetically encoded biosensor roGFP2 we studied for the first time the differences between the redox states of the cytosol, the intermembrane space of mitochondria and the ER in the filamentous fungus Botrytis cinerea. We showed that the ratio of oxidized to reduced glutathione inside of the cellular compartments differ and that the addition of hydrogen peroxide (H2O2), calcium chloride (CaCl2) and the fluorescent dye calcofluor white (CFW) have a direct impact on the cellular redox states. Dependent on the type of stress agents applied, the redox states were affected in the different cellular compartments in a temporally shifted manner. By integrating the biosensor in deletion mutants of bcnoxA, bcnoxB, bctrx1 and bcltf1 we further elucidated the putative roles of the different proteins in distinct stress-response pathways. We showed that the redox states of ΔbcnoxA and ΔbcnoxB display a wild-type pattern upon exposure to H2O2, but appear to be strongly affected by CaCl2 and CFW. Moreover, we demonstrated the involvement of the light-responsive transcription factor BcLtf1 in the maintenance of the redox state in the intermembrane space of the mitochondria. Finally, we report that CaCl2 as well as cell wall stress-inducing agents stimulate ROS production and that ΔbcnoxB produces significantly less ROS than the wild type and ΔbcnoxA.
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Leroch M, Mueller N, Hinsenkamp I, Hahn M. The signalling mucin Msb2 regulates surface sensing and host penetration via BMP1 MAP kinase signalling in Botrytis cinerea. MOLECULAR PLANT PATHOLOGY 2015; 16:787-98. [PMID: 25582910 PMCID: PMC6638485 DOI: 10.1111/mpp.12234] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Botrytis cinerea is a necrotrophic fungus that infects a wide range of fruit, vegetable and flower crops. Penetration of the host cuticle occurs via infection structures that are formed in response to appropriate plant surface signals. The differentiation of these structures requires a highly conserved mitogen-activated protein (MAP) kinase cascade including the MAP kinase BMP1. In yeast and several plant-pathogenic fungi, the signalling mucin Msb2 has been shown to be involved in surface recognition and MAP kinase activation. In this study, a B. cinerea msb2 mutant was generated and characterized. The mutant showed normal growth, sporulation, sclerotia formation and stress resistance. In the absence of nutrients, abnormal germination with multiple germ tubes was observed. In the presence of sugars, normal germination occurred, but msb2 germlings were almost unable to form appressoria or infection cushions on hard surfaces. Nevertheless, the msb2 mutant showed only a moderate delay in lesion formation on different host plants, and formed expanding lesions similar to the wild-type. Although the wild-type showed increasing BMP1 phosphorylation during the first hours of germination on hard surfaces, the phosphorylation levels in the msb2 mutant were strongly reduced. Several genes encoding secreted proteins were found to be co-regulated by BMP1 and Msb2 during germination. Taken together, B. cinerea Msb2 is likely to represent a hard surface sensor of germlings and hyphae that triggers infection structure formation via the activation of the BMP1 MAP kinase pathway.
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Affiliation(s)
- Michaela Leroch
- Department of Biology, University of Kaiserslautern, 67653, Kaiserslautern, Germany
| | - Nathalie Mueller
- Department of Biology, University of Kaiserslautern, 67653, Kaiserslautern, Germany
| | - Isabel Hinsenkamp
- Department of Biology, University of Kaiserslautern, 67653, Kaiserslautern, Germany
| | - Matthias Hahn
- Department of Biology, University of Kaiserslautern, 67653, Kaiserslautern, Germany
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Huang S, He Z, Zhang S, Keyhani NO, Song Y, Yang Z, Jiang Y, Zhang W, Pei Y, Zhang Y. Interplay between calcineurin and the Slt2 MAP-kinase in mediating cell wall integrity, conidiation and virulence in the insect fungal pathogen Beauveria bassiana. Fungal Genet Biol 2015; 83:78-91. [PMID: 26319315 DOI: 10.1016/j.fgb.2015.08.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2015] [Revised: 08/20/2015] [Accepted: 08/25/2015] [Indexed: 01/01/2023]
Abstract
The entomopathogenic fungus, Beauveria bassiana, is of environmental and economic importance as an insect pathogen, currently used for the biological control of a number of pests. Cell wall integrity and conidiation are critical parameters for the ability of the fungus to infect insects and for production of the infectious propagules. The contribution of calcineurin and the Slt2 MAP kinase to cell wall integrity and development in B. bassiana was investigated. Gene knockouts of either the calcineurin CNA1 subunit or the Slt2 MAP kinase resulted in decreased tolerance to calcofluor white and high temperature. In contrast, the Δcna1 strain was more tolerant to Congo red but more sensitive to osmotic stress (NaCl, sorbitol) than the wild type, whereas the Δslt2 strain had the opposite phenotype. Changes in cell wall structure and composition were seen in the Δslt2 and Δcna1 strains during growth under cell wall stress as compared to the wild type. Both Δslt2 and Δcna1 strains showed significant alterations in growth, conidiation, and viability. Elevation of intracellular ROS levels, and decreased conidial hydrophobicity and adhesion to hydrophobic surfaces, were also seen for both mutants, as well as decreased virulence. Under cell wall stress conditions, inactivation of Slt2 significantly repressed CN-mediated phosphatase activity suggesting some level of cross talk between the two pathways. Comparative transcriptome profiling of the Δslt2 and Δcna1 strains revealed alterations in the expression of distinct gene sets, with overlap in transcripts involved in cell wall integrity, stress response, conidiation and virulence. These data illustrate convergent and divergent phenotypes and targets of the calcineurin and Slt2 pathways in B. bassiana.
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Affiliation(s)
- Shuaishuai Huang
- College of Plant Protection, Biotechnology Research Center, Southwest University, Chongqing 400715, People's Republic of China
| | - Zhangjiang He
- College of Plant Protection, Biotechnology Research Center, Southwest University, Chongqing 400715, People's Republic of China
| | - Shiwei Zhang
- College of Plant Protection, Biotechnology Research Center, Southwest University, Chongqing 400715, People's Republic of China
| | - Nemat O Keyhani
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA
| | - Yulin Song
- College of Plant Protection, Biotechnology Research Center, Southwest University, Chongqing 400715, People's Republic of China
| | - Zhi Yang
- College of Plant Protection, Biotechnology Research Center, Southwest University, Chongqing 400715, People's Republic of China
| | - Yahui Jiang
- College of Plant Protection, Biotechnology Research Center, Southwest University, Chongqing 400715, People's Republic of China
| | - Wenli Zhang
- Medical Research Center, North China University of Science and Technology, Hebei 06000, People's Republic of China
| | - Yan Pei
- College of Plant Protection, Biotechnology Research Center, Southwest University, Chongqing 400715, People's Republic of China
| | - Yongjun Zhang
- College of Plant Protection, Biotechnology Research Center, Southwest University, Chongqing 400715, People's Republic of China.
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BcMctA, a putative monocarboxylate transporter, is required for pathogenicity in Botrytis cinerea. Curr Genet 2015; 61:545-53. [DOI: 10.1007/s00294-015-0474-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Revised: 01/14/2015] [Accepted: 01/15/2015] [Indexed: 10/24/2022]
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Li F, Wang ZL, Zhang LB, Ying SH, Feng MG. The role of three calcineurin subunits and a related transcription factor (Crz1) in conidiation, multistress tolerance and virulence in Beauveria bassiana. Appl Microbiol Biotechnol 2014; 99:827-40. [DOI: 10.1007/s00253-014-6124-6] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2014] [Revised: 09/28/2014] [Accepted: 09/30/2014] [Indexed: 11/25/2022]
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Functional analysis of BcBem1 and its interaction partners in Botrytis cinerea: impact on differentiation and virulence. PLoS One 2014; 9:e95172. [PMID: 24797931 PMCID: PMC4010548 DOI: 10.1371/journal.pone.0095172] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Accepted: 03/24/2014] [Indexed: 11/19/2022] Open
Abstract
In phytopathogenic fungi the establishment and maintenance of polarity is not only essential for vegetative growth and differentiation, but also for penetration and colonization of host tissues. We investigated orthologs of members of the yeast polarity complex in the grey mould fungus Botrytis cinerea: the scaffold proteins Bem1 and Far1, the GEF (guanine nucleotide exchange factor) Cdc24, and the formin Bni1 (named Sep1 in B. cinerea). BcBem1 does not play an important role in regular hyphal growth, but has significant impact on spore formation and germination, on the establishment of conidial anastomosis tubes (CATs) and on virulence. As in other fungi, BcBem1 interacts with the GEF BcCdc24 and the formin BcSep1, indicating that in B. cinerea the apical complex has a similar structure as in yeast. A functional analysis of BcCdc24 suggests that it is essential for growth, since it was not possible to obtain homokaryotic deletion mutants. Heterokaryons of Δcdc24 (supposed to exhibit reduced bccdc24 transcript levels) already show a strong phenotype: an inability to penetrate the host tissue, a significantly reduced growth rate and malformation of conidia, which tend to burst as observed for Δbcbem1. Also the formin BcSep1 has significant impact on hyphal growth and development, whereas the role of the putative ortholog of the yeast scaffold protein Far1 remains open: Δbcfar1 mutants have no obvious phenotypes.
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Harren K, Brandhoff B, Knödler M, Tudzynski B. The high-affinity phosphodiesterase BcPde2 has impact on growth, differentiation and virulence of the phytopathogenic ascomycete Botrytis cinerea. PLoS One 2013; 8:e78525. [PMID: 24265695 PMCID: PMC3827054 DOI: 10.1371/journal.pone.0078525] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Accepted: 09/19/2013] [Indexed: 01/19/2023] Open
Abstract
Components of the cAMP signaling pathway, such as the adenylate cyclase Bac and the protein kinase A (PKA) were shown to affect growth, morphogenesis and differentiation as well as virulence of the phytopathogenic fungus Botrytis cinerea. While loss of Bac caused drastically reduced intracellular cAMP levels, deletion of the PKA resulted in extremely increased cAMP concentrations. To regulate the intracellular level of the second messenger cAMP, a balance between its biosynthesis through adenylate cyclase activity and its hydrolysis by phosphodiesterases (PDEs) is crucial. Here, we report the functional characterization of the two PDEs in the ascomycete B. cinerea, BcPde1 and BcPde2. While deletion of bcpde2 resulted in severely affected vegetative growth, conidiation, germination and virulence, the bcpde1 deletion strain displayed a wild-type-like phenotype. However, the double bcpde1/2 deletion mutant exhibited an even stronger phenotype. Localization studies revealed that BcPde2 accumulates at the plasma membrane, but is also localized in the cytoplasm. BcPde1 was shown to be distributed in the cytoplasm as well, but also accumulates in so far unknown mobile vesicles. Overexpression of bcpde1 in the Δbcpde2 background rescued the deletion phenotype, and in addition an increased transcript level of bcpde1 in the Δbcpde2 strain was observed, indicating redundant functions of both PDEs and an interdependent gene expression.
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Affiliation(s)
- Karin Harren
- Westfälische Wilhelms-Universität Münster, Institute of Biology and Biotechnology of Plants, Münster, Germany
| | - Beate Brandhoff
- Westfälische Wilhelms-Universität Münster, Institute of Biology and Biotechnology of Plants, Münster, Germany
| | - Michael Knödler
- Westfälische Wilhelms-Universität Münster, Institute of Biology and Biotechnology of Plants, Münster, Germany
| | - Bettina Tudzynski
- Westfälische Wilhelms-Universität Münster, Institute of Biology and Biotechnology of Plants, Münster, Germany
- * E-mail:
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Involvement of Botrytis cinerea small GTPases BcRAS1 and BcRAC in differentiation, virulence, and the cell cycle. EUKARYOTIC CELL 2013; 12:1609-18. [PMID: 24096906 DOI: 10.1128/ec.00160-13] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Small GTPases of the Ras superfamily are highly conserved proteins that are involved in various cellular processes, in particular morphogenesis, differentiation, and polar growth. Here we report on the analysis of RAS1 and RAC homologues from the gray mold fungus Botrytis cinerea. We show that these small GTPases are individually necessary for polar growth, reproduction, and pathogenicity, required for cell cycle progression through mitosis (BcRAC), and may lie upstream of the stress-related mitogen-activated protein kinase (MAPK) signaling pathway. bcras1 and bcrac deletion strains had reduced growth rates, and their hyphae were hyperbranched and deformed. In addition, both strains were vegetatively sterile and nonpathogenic. A strain expressing a constitutively active (CA) allele of the BcRAC protein had partially similar but milder phenotypes. Similar to the deletion strains, the CA-BcRAC strain did not produce any conidia and had swollen hyphae. In contrast to the two deletion strains, however, the growth rate of the CA-BcRAC strain was normal, and it caused delayed but well-developed disease symptoms. Microscopic examination revealed an increased number of nuclei and disturbance of actin localization in the CA-BcRAC strain. Further work with cell cycle- and RAC-specific inhibitory compounds associated the BcRAC protein with progression of the cell cycle through mitosis, possibly via an effect on microtubules. Together, these results show that the multinucleate phenotype of the CA-BcRAC strain could result from at least two defects: disruption of polar growth through disturbed actin localization and uncontrolled nuclear division due to constitutive activity of BcRAC.
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Calcineurin plays key roles in the dimorphic transition and virulence of the human pathogenic zygomycete Mucor circinelloides. PLoS Pathog 2013; 9:e1003625. [PMID: 24039585 PMCID: PMC3764228 DOI: 10.1371/journal.ppat.1003625] [Citation(s) in RCA: 119] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2013] [Accepted: 06/27/2013] [Indexed: 11/19/2022] Open
Abstract
Many pathogenic fungi are dimorphic and switch between yeast and filamentous states. This switch alters host-microbe interactions and is critical for pathogenicity. However, in zygomycetes, whether dimorphism contributes to virulence is a central unanswered question. The pathogenic zygomycete Mucor circinelloides exhibits hyphal growth in aerobic conditions but switches to multi-budded yeast growth under anaerobic/high CO₂ conditions. We found that in the presence of the calcineurin inhibitor FK506, Mucor exhibits exclusively multi-budded yeast growth. We also found that M. circinelloides encodes three calcineurin catalytic A subunits (CnaA, CnaB, and CnaC) and one calcineurin regulatory B subunit (CnbR). Mutations in the latch region of CnbR and in the FKBP12-FK506 binding domain of CnaA result in hyphal growth of Mucor in the presence of FK506. Disruption of the cnbR gene encoding the sole calcineurin B subunit necessary for calcineurin activity yielded mutants locked in permanent yeast phase growth. These findings reveal that the calcineurin pathway plays key roles in the dimorphic transition from yeast to hyphae. The cnbR yeast-locked mutants are less virulent than the wild-type strain in a heterologous host system, providing evidence that hyphae or the yeast-hyphal transition are linked to virulence. Protein kinase A activity (PKA) is elevated during yeast growth under anaerobic conditions, in the presence of FK506, or in the yeast-locked cnbR mutants, suggesting a novel connection between PKA and calcineurin. cnaA mutants lacking the CnaA catalytic subunit are hypersensitive to calcineurin inhibitors, display a hyphal polarity defect, and produce a mixture of yeast and hyphae in aerobic culture. The cnaA mutants also produce spores that are larger than wild-type, and spore size is correlated with virulence potential. Our results demonstrate that the calcineurin pathway orchestrates the yeast-hyphal and spore size dimorphic transitions that contribute to virulence of this common zygomycete fungal pathogen.
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Yang Q, Yu F, Yin Y, Ma Z. Involvement of protein tyrosine phosphatases BcPtpA and BcPtpB in regulation of vegetative development, virulence and multi-stress tolerance in Botrytis cinerea. PLoS One 2013; 8:e61307. [PMID: 23585890 PMCID: PMC3621866 DOI: 10.1371/journal.pone.0061307] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Accepted: 03/07/2013] [Indexed: 12/20/2022] Open
Abstract
Tyrosine phosphorylation and dephosphorylation have emerged as fundamentally important mechanisms of signal transduction and regulation in eukaryotic cells, governing many processes, but little has been known about their functions in filamentous fungi. In this study, we deleted two putative protein tyrosine phosphatase (PTP) genes (BcPTPA and BcPTPB) in Botrytis cinerea, encoding the orthologs of Saccharomyces cerevisiae Ptp2 and Ptp3, respectively. Although BcPtpA and BcPtpB have opposite functions in conidiation, they are essential for sclerotial formation in B. cinerea. BcPTPA and BcPTPB deletion mutants ΔBcPtpA-10 and ΔBcPtpB-4 showed significantly increased sensitivity to osmotic and oxidative stresses, and to cell wall damaging agents. Inoculation tests showed that both mutants exhibited dramatically decreased virulence on tomato leaves, apples and grapes. In S. cerevisiae, it has been shown that Ptp2 and Ptp3 negatively regulate the high-osmolarity glycerol (HOG) pathway and the cell wall integrity (CWI) pathway. Although both BcPtpA and BcPtpB were able to inactive Hog1 and Mpk1 in S. cerevisiae, in contrast to S. cerevisiae, they positively regulate phosphorylation of BcSak1 (the homologue of Hog1) and BcBmp3 (the homologue of Mpk1) in B. cinerea under stress conditions. These results demonstrated that functions of PTPs in B. cinerea are different from those in S. cerevisiae, and BcPtpA and BcPtpB play important roles in regulation of vegetative development, virulence and in adaptation to oxidative, osmotic and cell-wall damage stresses in B. cinerea.
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Affiliation(s)
- Qianqian Yang
- Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Fangwei Yu
- Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Yanni Yin
- Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Zhonghua Ma
- Institute of Biotechnology, Zhejiang University, Hangzhou, China
- * E-mail:
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Cch1 and Mid1 are functionally required for vegetative growth under low-calcium conditions in the phytopathogenic ascomycete Botrytis cinerea. EUKARYOTIC CELL 2013; 12:712-24. [PMID: 23475703 DOI: 10.1128/ec.00338-12] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
In the filamentous phytopathogen Botrytis cinerea, the Ca(2+)/calcineurin signaling cascade has been shown to play an important role in fungal growth, differentiation, and virulence. This study deals with the functional characterization of two components of this pathway, the putative calcium channel proteins Cch1 and Mid1. The cch1 and mid1 genes were deleted, and single and double knockout mutants were analyzed during different stages of the fungal life cycle. Our data indicate that Cch1 and Mid1 are functionally required for vegetative growth under conditions of low extracellular calcium, since the growth of both deletion mutants is strongly impaired when they are exposed to the Ca(2+)-chelating agents EGTA and 1,2-bis(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA). The impact of external Ca(2+) was investigated by supplementing with CaCl(2) and the ionophore A23187, both of which resulted in elevated growth for all mutants. However, deletion of either gene had no impact on germination, sporulation, hyphal morphology, or virulence. By use of the aequorin reporter system to measure intracellular calcium levels, no differences between the mutant strains and the wild type were obtained. Localization studies revealed a subcellular distribution of the Mid1-green fluorescent protein (GFP) fusion protein in network-like filaments, probably the endoplasmic reticulum (ER) membranes, indicating that Mid1 is not a plasma membrane-located calcium channel in B. cinerea.
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Santos DWCL, Padovan ACB, Melo ASA, Gonçalves SS, Azevedo VR, Ogawa MM, Freitas TVS, Colombo AL. Molecular identification of melanised non-sporulating moulds: a useful tool for studying the epidemiology of phaeohyphomycosis. Mycopathologia 2013; 175:445-54. [PMID: 23288581 DOI: 10.1007/s11046-012-9608-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Accepted: 12/11/2012] [Indexed: 10/27/2022]
Abstract
Subcutaneous infections caused by melanised fungi have been increasingly reported among transplant patients, and these infections have the potential for blood and visceral dissemination. Some moulds, such as Mycelia sterilia, cannot grow and sporulate on different media, making their identification impossible by conventional methods. The fast and accurate identification of melanised fungi at the species level is important because species may have tropism to different organs and different susceptibilities to antifungal agents. Molecular tools have been reported to be helpful for the species identification of non-sporulating moulds. Our goal was to identify the species of M. sterilia isolates obtained from clinical samples of transplant patients using sequences of ITS and the D1/D2 regions of rDNA. Clinical samples were obtained from eight kidney transplant recipients who developed subcutaneous fungal infections. The diagnosis was confirmed by histopathology and conventional culture. Histopathology showed septated, melanised hyphae, and the cultures identified non-sporulating fungi. Therefore, the DNA from the M. sterilia isolates was subjected to PCR amplification and sequencing of the ITS and D1/D2 regions. Genus/species identification was obtained by comparison with gene banks. We obtained the following identifications: Alternaria sp. (2), Cochliobolus lunatus/Curvularia lunata (2), Cochliobolus hawaiiensis/Bipolaris hawaiiensis (1), Ochroconis sp. (1), Medicocopsis romeroi/Pyrenochaeta romeroi (1) and Nigrograna mackinnonii/Pyrenochaeta mackinnonii (1).
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Affiliation(s)
- Daniel W C L Santos
- Special Mycology Laboratory-LEMI, Department of Medicine, Federal University of São Paulo, São Paulo, SP, Brazil
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