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Li Z, Zhao C, Zhou Y, Zheng S, Hu Q, Zou Y. Label-free comparative proteomic analysis of Pleurotus eryngii grown on sawdust, bagasse, and peanut shell substrates. J Proteomics 2024; 294:105074. [PMID: 38199305 DOI: 10.1016/j.jprot.2024.105074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Revised: 12/29/2023] [Accepted: 01/03/2024] [Indexed: 01/12/2024]
Abstract
The white rot fungi Pleurotus eryngii are environmental microorganisms that can effectively break down lignocellulosic biomass. However, understanding of the mechanisms by which P. eryngii is effective in degrading lignocellulose is still limited. This work aimed to examine the extracellular secretory proteins implicated in the breakdown of lignocellulose in P. eryngii and identify degradation tactics across various cultivation substrates. Thus, a comparative analysis of the secretory proteins based on Nanoliquid chromatography combined with tandem mass spectrometry was conducted among P. eryngii cultivated on sawdusts, bagasse, peanut shells, and glucose. In total, 647, 616, 604, and 511 proteins were identified from the four samples, respectively. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis of protein expression differences identified pathways (hydrolytic enzymes, catalytic activity, metabolic processes, cellular processes, and response to stimuli) significantly enriched in proteins associated with lignocellulose degradation in P. eryngii. An integrated analysis of proteome data revealed specifically or differentially expressed genes secreted by P. eryngii in different cultivation substrates. The most prevalent carbohydrate-active enzymes involved in lignocellulose degradation in the secretome of the four samples were laccase (Lac), manganese peroxidase (MnP), aryl alcohol oxidase (AaO), and copper radical oxidase (CRO). Among them, Lac 2 mainly involved in the lignin degradation of sawdust peanut shells, and bagasse by P. eryngii, and Mnp 3 was mainly involved in the degradation of peanut shells. AaO and Lac 4 were mainly involved in glucose substrate defense and oxidative stress. It was found that exogenous addition of sawdust and peanut shells significantly increased lignolytic enzyme abundance. These findings provide insight and guidance for improving agricultural waste resource recovery. In this study, the secretomes of P. eryngii grown on four different carbon sources were compared. The findings revealed the extracellular enzymes implicated in the degradation of lignocellulose, offering avenues for further investigation into the biotransformation mechanisms of P. eryngii biomass and the potential utilization of agricultural wastes. SIGNIFICANCE: The cost of the substrate for mushroom cultivation has increased as the production of edible fungus has risen year after year. Therefore, the use of these locally available lignocellulosic wastes as substrates offers a cost-cutting option. Further, the overuse of wood for the cultivation of edible mushrooms is also detrimental to the conservation of forest resources or the ecological environment. Consequently, the use of other agricultural wastes as an alternative to sawdust or other woody substrates is a viable approach for cultivating P. eryngii. The distribution of extracellular lignocellulosic degrading enzymes, inferred in the present study could help improve the cultivation efficiency of P. eryngii vis-à-vis managing agricultural waste.
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Affiliation(s)
- Zihao Li
- State Key Laboratory of Efficient Utilization of Arid and Semi-Arid Arable Land in Northern China, Beijing 100081, China; Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Cuimin Zhao
- State Key Laboratory of Efficient Utilization of Arid and Semi-Arid Arable Land in Northern China, Beijing 100081, China; Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China; Department of Gardens and Ecological Engineering, Hebei University of Engineering, Handan, China; Liaocheng Academy of Agricultural Sciences, Liaocheng, China
| | - Yuanyuan Zhou
- State Key Laboratory of Efficient Utilization of Arid and Semi-Arid Arable Land in Northern China, Beijing 100081, China; Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Suyue Zheng
- Department of Gardens and Ecological Engineering, Hebei University of Engineering, Handan, China
| | - Qingxiu Hu
- State Key Laboratory of Efficient Utilization of Arid and Semi-Arid Arable Land in Northern China, Beijing 100081, China; Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Yajie Zou
- State Key Laboratory of Efficient Utilization of Arid and Semi-Arid Arable Land in Northern China, Beijing 100081, China; Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
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Mattila H, Österman-Udd J, Mali T, Lundell T. Basidiomycota Fungi and ROS: Genomic Perspective on Key Enzymes Involved in Generation and Mitigation of Reactive Oxygen Species. FRONTIERS IN FUNGAL BIOLOGY 2022; 3:837605. [PMID: 37746164 PMCID: PMC10512322 DOI: 10.3389/ffunb.2022.837605] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 02/21/2022] [Indexed: 09/26/2023]
Abstract
Our review includes a genomic survey of a multitude of reactive oxygen species (ROS) related intra- and extracellular enzymes and proteins among fungi of Basidiomycota, following their taxonomic classification within the systematic classes and orders, and focusing on different fungal lifestyles (saprobic, symbiotic, pathogenic). Intra- and extracellular ROS metabolism-involved enzymes (49 different protein families, summing 4170 protein models) were searched as protein encoding genes among 63 genomes selected according to current taxonomy. Extracellular and intracellular ROS metabolism and mechanisms in Basidiomycota are illustrated in detail. In brief, it may be concluded that differences between the set of extracellular enzymes activated by ROS, especially by H2O2, and involved in generation of H2O2, follow the differences in fungal lifestyles. The wood and plant biomass degrading white-rot fungi and the litter-decomposing species of Agaricomycetes contain the highest counts for genes encoding various extracellular peroxidases, mono- and peroxygenases, and oxidases. These findings further confirm the necessity of the multigene families of various extracellular oxidoreductases for efficient and complete degradation of wood lignocelluloses by fungi. High variations in the sizes of the extracellular ROS-involved gene families were found, however, among species with mycorrhizal symbiotic lifestyle. In addition, there are some differences among the sets of intracellular thiol-mediation involving proteins, and existence of enzyme mechanisms for quenching of intracellular H2O2 and ROS. In animal- and plant-pathogenic species, extracellular ROS enzymes are absent or rare. In these fungi, intracellular peroxidases are seemingly in minor role than in the independent saprobic, filamentous species of Basidiomycota. Noteworthy is that our genomic survey and review of the literature point to that there are differences both in generation of extracellular ROS as well as in mechanisms of response to oxidative stress and mitigation of ROS between fungi of Basidiomycota and Ascomycota.
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Affiliation(s)
| | | | | | - Taina Lundell
- Department of Microbiology, Faculty of Agriculture and Forestry, Viikki Campus, University of Helsinki, Helsinki, Finland
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Lofgren LA, Nguyen NH, Vilgalys R, Ruytinx J, Liao HL, Branco S, Kuo A, LaButti K, Lipzen A, Andreopoulos W, Pangilinan J, Riley R, Hundley H, Na H, Barry K, Grigoriev IV, Stajich JE, Kennedy PG. Comparative genomics reveals dynamic genome evolution in host specialist ectomycorrhizal fungi. THE NEW PHYTOLOGIST 2021; 230:774-792. [PMID: 33355923 PMCID: PMC7969408 DOI: 10.1111/nph.17160] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 12/16/2020] [Indexed: 05/24/2023]
Abstract
While there has been significant progress characterizing the 'symbiotic toolkit' of ectomycorrhizal (ECM) fungi, how host specificity may be encoded into ECM fungal genomes remains poorly understood. We conducted a comparative genomic analysis of ECM fungal host specialists and generalists, focusing on the specialist genus Suillus. Global analyses of genome dynamics across 46 species were assessed, along with targeted analyses of three classes of molecules previously identified as important determinants of host specificity: small secreted proteins (SSPs), secondary metabolites (SMs) and G-protein coupled receptors (GPCRs). Relative to other ECM fungi, including other host specialists, Suillus had highly dynamic genomes including numerous rapidly evolving gene families and many domain expansions and contractions. Targeted analyses supported a role for SMs but not SSPs or GPCRs in Suillus host specificity. Phylogenomic-based ancestral state reconstruction identified Larix as the ancestral host of Suillus, with multiple independent switches between white and red pine hosts. These results suggest that like other defining characteristics of the ECM lifestyle, host specificity is a dynamic process at the genome level. In the case of Suillus, both SMs and pathways involved in the deactivation of reactive oxygen species appear to be strongly associated with enhanced host specificity.
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Affiliation(s)
- Lotus A Lofgren
- Department of Microbiology and Plant Pathology, University of California Riverside, Riverside, CA, 92507, USA
- Department of Plant and Microbial Biology, University of Minnesota, St Paul, MN, 55108, USA
| | - Nhu H Nguyen
- Department of Tropical Plant and Soil Science, University of Hawaii, Manoa, HI, 96822, USA
| | - Rytas Vilgalys
- Department of Biology, Duke University, Durham, NC, 27708, USA
| | - Joske Ruytinx
- Research group Microbiology, Department of Bio-engineering Sciences, Vrije Universiteit Brussel, Brussel, BE1500, Belgium
| | - Hui-Ling Liao
- Department of Soil Microbial Ecology, University of Florida, Quincy, FL, 32351, USA
| | - Sara Branco
- Department of Integrative Biology, University of Colorado Denver, Denver, CO, 80204, USA
| | - Alan Kuo
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Kurt LaButti
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Anna Lipzen
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - William Andreopoulos
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Jasmyn Pangilinan
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Robert Riley
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Hope Hundley
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Hyunsoo Na
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Kerrie Barry
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Igor V Grigoriev
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, 94720, USA
| | - Jason E Stajich
- Department of Microbiology and Plant Pathology, University of California Riverside, Riverside, CA, 92507, USA
| | - Peter G Kennedy
- Department of Plant and Microbial Biology, University of Minnesota, St Paul, MN, 55108, USA
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Wang L, Cai X, Xing J, Liu C, Hendy A, Chen XL. URM1-Mediated Ubiquitin-Like Modification Is Required for Oxidative Stress Adaptation During Infection of the Rice Blast Fungus. Front Microbiol 2019; 10:2039. [PMID: 31551975 PMCID: PMC6746893 DOI: 10.3389/fmicb.2019.02039] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 08/19/2019] [Indexed: 12/17/2022] Open
Abstract
Ubiquitin is a small modifier protein which is usually conjugated to substrate proteins for degradation. In recent years, a number of ubiquitin-like proteins have been identified; however, their roles in eukaryotes are largely unknown. Here, we describe a ubiquitin-like protein URM1, and found it plays important roles in the development and infection process of the rice blast fungus, Magnaporthe oryzae. Targeted deletion of URM1 in M. oryzae resulted in slight reduction in vegetative growth and significant decrease in conidiation. More importantly, the Δurm1 mutant also showed evident reduction in virulence to host plants. Infection process observation demonstrated that the mutant was arrested in invasive growth and resulted in accumulation of massive host reactive oxygen species (ROS). Further, we found the Δurm1 mutant was sensitive to the cell wall disturbing reagents, thiol oxidizing agent diamide and rapamycin. We also showed that URM1-mediated modification was responsive to oxidative stresses, and the thioredoxin peroxidase Ahp1 was one of the important urmylation targets. These results suggested that URM1-mediated urmylation plays important roles in detoxification of host oxidative stress to facilitate invasive growth in M. oryzae.
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Affiliation(s)
- Luyang Wang
- The Provincial Key Lab of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Xuan Cai
- The Provincial Key Lab of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Junjie Xing
- State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Center, Changsha, China
| | - Caiyun Liu
- The Provincial Key Lab of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Ahmed Hendy
- The Provincial Key Lab of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China.,Department of Agricultural Botany, Faculty of Agriculture (Saba Basha), Alexandria University, Alexandria, Egypt
| | - Xiao-Lin Chen
- The Provincial Key Lab of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China.,State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Center, Changsha, China
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Tamayo E, Benabdellah K, Ferrol N. Characterization of Three New Glutaredoxin Genes in the Arbuscular Mycorrhizal Fungus Rhizophagus irregularis: Putative Role of RiGRX4 and RiGRX5 in Iron Homeostasis. PLoS One 2016; 11:e0149606. [PMID: 26900849 PMCID: PMC4765768 DOI: 10.1371/journal.pone.0149606] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 02/02/2016] [Indexed: 01/07/2023] Open
Abstract
Glutaredoxins (GRXs) are small ubiquitous oxidoreductases involved in the regulation of the redox state in living cells. In an attempt to identify the full complement of GRXs in the arbuscular mycorrhizal (AM) fungus Rhizophagus irregularis, three additional GRX homologs, besides the formerly characterized GintGRX1 (renamed here as RiGRX1), were identified. The three new GRXs (RiGRX4, RiGRX5 and RiGRX6) contain the CXXS domain of monothiol GRXs, but whereas RiGRX4 and RiGRX5 belong to class II GRXs, RiGRX6 belongs to class I together with RiGRX1. By using a yeast expression system, we observed that the newly identified homologs partially reverted sensitivity of the GRX deletion yeast strains to external oxidants. Furthermore, our results indicated that RiGRX4 and RiGRX5 play a role in iron homeostasis in yeast. Gene expression analyses revealed that RiGRX1 and RiGRX6 were more highly expressed in the intraradical (IRM) than in the extraradical mycelium (ERM). Exposure of the ERM to hydrogen peroxide induced up-regulation of RiGRX1, RiGRX4 and RiGRX5 gene expression. RiGRX4 expression was also up-regulated in the ERM when the fungus was grown in media supplemented with a high iron concentration. These data indicate the two monothiol class II GRXs, RiGRX4 and RiGRX5, might be involved in oxidative stress protection and in the regulation of fungal iron homeostasis. Increased expression of RiGRX1 and RiGRX6 in the IRM suggests that these GRXs should play a key role in oxidative stress protection of R. irregularis during its in planta phase.
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Affiliation(s)
- Elisabeth Tamayo
- Departamento de Microbiología del Suelo y Sistemas Simbióticos, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - Karim Benabdellah
- Genomic Medicine Department, GENYO, Centre for Genomics and Oncological Research, Pfizer-University of Granada-Andalusian Regional Government, Parque Tecnológico Ciencias de la Salud, Granada, Spain
| | - Nuria Ferrol
- Departamento de Microbiología del Suelo y Sistemas Simbióticos, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
- * E-mail:
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6
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Wang G, Wang H, Xiong X, Chen S, Zhang D. Mitochondria thioredoxin's backup role in oxidative stress resistance in Trichoderma reesei. Microbiol Res 2015; 171:32-8. [DOI: 10.1016/j.micres.2015.01.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Revised: 01/01/2015] [Accepted: 01/03/2015] [Indexed: 10/24/2022]
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Kuo A, Kohler A, Martin FM, Grigoriev IV. Expanding genomics of mycorrhizal symbiosis. Front Microbiol 2014; 5:582. [PMID: 25408690 PMCID: PMC4219462 DOI: 10.3389/fmicb.2014.00582] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Accepted: 10/15/2014] [Indexed: 12/11/2022] Open
Abstract
The mycorrhizal symbiosis between soil fungi and plant roots is a ubiquitous mutualism that plays key roles in plant nutrition, soil health, and carbon cycling. The symbiosis evolved repeatedly and independently as multiple morphotypes [e.g., arbuscular mycorrhizae (AM), ectomycorrhizal (ECM)] in multiple fungal clades (e.g., phyla Glomeromycota, Ascomycota, Basidiomycota). The accessibility and cultivability of many mycorrhizal partners make them ideal models for symbiosis studies. Alongside molecular, physiological, and ecological investigations, sequencing led to the first three mycorrhizal fungal genomes, representing two morphotypes and three phyla. The genome of the ECM basidiomycete Laccaria bicolor showed that the mycorrhizal lifestyle can evolve through loss of plant cell wall-degrading enzymes (PCWDEs) and expansion of lineage-specific gene families such as short secreted protein (SSP) effectors. The genome of the ECM ascomycete Tuber melanosporum showed that the ECM type can evolve without expansion of families as in Laccaria, and thus a different set of symbiosis genes. The genome of the AM glomeromycete Rhizophagus irregularis showed that despite enormous phylogenetic distance and morphological difference from the other two fungi, symbiosis can involve similar solutions as symbiosis-induced SSPs and loss of PCWDEs. The three genomes provide a solid base for addressing fundamental questions about the nature and role of a vital mutualism.
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Affiliation(s)
- Alan Kuo
- United States Department of Energy Joint Genome InstituteWalnut Creek, CA, USA
| | - Annegret Kohler
- UMR, Lab of Excellence for Advanced Research on the Biology of TRee and Forest Ecosystems, Tree-Microbe Interactions, Institut National de la Recherche Agronomique, Université de LorraineNancy, France
| | - Francis M. Martin
- UMR, Lab of Excellence for Advanced Research on the Biology of TRee and Forest Ecosystems, Tree-Microbe Interactions, Institut National de la Recherche Agronomique, Université de LorraineNancy, France
| | - Igor V. Grigoriev
- United States Department of Energy Joint Genome InstituteWalnut Creek, CA, USA
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Transcriptomic responses of Phanerochaete chrysosporium to oak acetonic extracts: focus on a new glutathione transferase. Appl Environ Microbiol 2014; 80:6316-27. [PMID: 25107961 DOI: 10.1128/aem.02103-14] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
The first steps of wood degradation by fungi lead to the release of toxic compounds known as extractives. To better understand how lignolytic fungi cope with the toxicity of these molecules, a transcriptomic analysis of Phanerochaete chrysosporium genes was performed in the presence of oak acetonic extracts. It reveals that in complement to the extracellular machinery of degradation, intracellular antioxidant and detoxification systems contribute to the lignolytic capabilities of fungi, presumably by preventing cellular damages and maintaining fungal health. Focusing on these systems, a glutathione transferase (P. chrysosporium GTT2.1 [PcGTT2.1]) has been selected for functional characterization. This enzyme, not characterized so far in basidiomycetes, has been classified first as a GTT2 compared to the Saccharomyces cerevisiae isoform. However, a deeper analysis shows that the GTT2.1 isoform has evolved functionally to reduce lipid peroxidation by recognizing high-molecular-weight peroxides as substrates. Moreover, the GTT2.1 gene has been lost in some non-wood-decay fungi. This example suggests that the intracellular detoxification system evolved concomitantly with the extracellular ligninolytic machinery in relation to the capacity of fungi to degrade wood.
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Samalova M, Meyer AJ, Gurr SJ, Fricker MD. Robust anti-oxidant defences in the rice blast fungus Magnaporthe oryzae confer tolerance to the host oxidative burst. THE NEW PHYTOLOGIST 2014; 201:556-573. [PMID: 24117971 DOI: 10.1111/nph.12530] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Accepted: 08/20/2013] [Indexed: 05/22/2023]
Abstract
Plants respond to pathogen attack via a rapid burst of reactive oxygen species (ROS). However, ROS are also produced by fungal metabolism and are required for the development of infection structures in Magnaporthe oryzae. To obtain a better understanding of redox regulation in M. oryzae, we measured the amount and redox potential of glutathione (E(GSH)), as the major cytoplasmic anti-oxidant, the rates of ROS production, and mitochondrial activity using multi-channel four-dimensional (x,y,z,t) confocal imaging of Grx1-roGFP2 and fluorescent reporters during spore germination, appressorium formation and infection. High levels of mitochondrial activity and ROS were localized to the growing germ tube and appressorium, but E(GSH) was highly reduced and tightly regulated during development. Furthermore, germlings were extremely resistant to external H2O2 exposure ex planta. EGSH remained highly reduced during successful infection of the susceptible rice cultivar CO39. By contrast, there was a dramatic reduction in the infection of resistant (IR68) rice, but the sparse hyphae that did form also maintained a similar reduced E(GSH). We conclude that M. oryzae has a robust anti-oxidant defence system and maintains tight control of EGSH despite substantial oxidative challenge. Furthermore, the magnitude of the host oxidative burst alone does not stress the pathogen sufficiently to prevent infection in this pathosystem.
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Affiliation(s)
- Marketa Samalova
- Department of Plant Sciences, University of Oxford, South Parks Road, Oxford, OX1 3RB, UK
| | - Andreas J Meyer
- INRES, Universität Bonn, Friedrich-Ebert-Allee 144, D-53113, Bonn, Germany
| | - Sarah J Gurr
- Department of Plant Sciences, University of Oxford, South Parks Road, Oxford, OX1 3RB, UK
- Biosciences, University of Exeter, Devon, EX4 4QD, UK
| | - Mark D Fricker
- Department of Plant Sciences, University of Oxford, South Parks Road, Oxford, OX1 3RB, UK
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Redox regulation of an AP-1-like transcription factor, YapA, in the fungal symbiont Epichloe festucae. EUKARYOTIC CELL 2013; 12:1335-48. [PMID: 23893078 DOI: 10.1128/ec.00129-13] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
One of the central regulators of oxidative stress in Saccharomyces cerevisiae is Yap1, a bZIP transcription factor of the AP-1 family. In unstressed cells, Yap1 is reduced and cytoplasmic, but in response to oxidative stress, it becomes oxidized and accumulates in the nucleus. To date, there have been no reports on the role of AP-1-like transcription factors in symbiotic fungi. An ortholog of Yap1, named YapA, was identified in the genome of the grass symbiont Epichloë festucae and shown to complement an S. cerevisiae Δyap1 mutant. Hyphae of the E. festucae ΔyapA strain were sensitive to menadione and diamide but resistant to H2O2, KO2, and tert-butyl hydroperoxide (t-BOOH). In contrast, conidia of the ΔyapA strain were very sensitive to H2O2 and failed to germinate. Using a PcatA-eGFP degron-tagged reporter, YapA was shown to be required for expression of a spore-specific catalase gene, catA. Although YapA-EGFP localized to the nucleus in response to host reactive oxygen species during seedling infection, there was no difference in whole-plant and cellular phenotypes of plants infected with the ΔyapA strain compared to the wild-type strain. Homologs of the S. cerevisiae and Schizosaccharomyces pombe redox-sensing proteins (Gpx3 and Tpx1, respectively) did not act as redox sensors for YapA in E. festucae. In response to oxidative stress, YapA-EGFP localized to the nuclei of E. festucae ΔgpxC, ΔtpxA, and ΔgpxC ΔtpxA cells to the same degree as that in wild-type cells. These results show that E. festucae has a robust system for countering oxidative stress in culture and in planta but that Gpx3- or Tpx1-like thiol peroxidases are dispensable for activation of YapA.
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Nagy NE, Fossdal CG. Host responses in Norway spruce roots induced to the pathogen Ceratocystis polonica are evaded or suppressed by the ectomycorrhizal fungus Laccaria bicolor. PLANT BIOLOGY (STUTTGART, GERMANY) 2013; 15:99-110. [PMID: 22640005 DOI: 10.1111/j.1438-8677.2012.00596.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The outcome of a compatible mycorrhizal interaction is different from that in a compatible plant-pathogen interaction; however, it is not clear what mechanisms are used to evade or suppress the host defence. The aim of this work is to reveal differences between the interaction of Norway spruce roots to the pathogen Ceratocystis polonica and the ectomycorrhizal Laccaria bicolor, examine if L. bicolor is able to evade inducing host defence responses typically induced by pathogens, and test if prior inoculation with the ectomycorrhizal fungus affects the outcome of a later challenge with the pathogen. The pathogen was able to invade the roots and caused extensive necrosis, leading to seedling death, with or without prior inoculation with L. bicolor. The ectomycorrhizal L. bicolor colonised primary roots of the Norway spruce seedlings by partly covering, displacing and convoluting the cells of the outer root cortex, leaving the seedlings healthy. We detected increased total peroxidase activity, and staining indicating increased lignification in roots as a response to C. polonica. In L. bicolor inoculated roots there was no increase in total peroxidase activity, but an additional highly acidic peroxidase isoform appeared that was not present in healthy roots, or in roots invaded by the pathogen. Increased protease activity was detected in roots colonised by C. polonica, but little protease activity was detected in L. bicolor inoculated roots. These results suggest that the pathogen efficiently invades the roots despite the induced host defence responses, while L. bicolor suppresses or evades inducing such host responses in this experimental system.
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Affiliation(s)
- N E Nagy
- Norwegian Forest and Landscape Institute, Aas, Norway
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Asiimwe T, Krause K, Schlunk I, Kothe E. Modulation of ethanol stress tolerance by aldehyde dehydrogenase in the mycorrhizal fungus Tricholoma vaccinum. MYCORRHIZA 2012; 22:471-484. [PMID: 22159964 DOI: 10.1007/s00572-011-0424-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Accepted: 11/25/2011] [Indexed: 05/28/2023]
Abstract
We report the first mycorrhizal fungal aldehyde dehydrogenase gene, ald1, which was isolated from the basidiomycete Tricholoma vaccinum. The gene, encoding a protein Ald1 of 502 amino acids, is up-regulated in ectomycorrhiza. Phylogenetic analyses using 53 specific fungal aldehyde dehydrogenases from all major phyla in the kingdom of fungi including Ald1 and two partial sequences of T. vaccinum were performed to get an insight in the evolution of the aldehyde dehydrogenase family. By using competitive and real-time RT-PCR, ald1 is up-regulated in response to alcohol and aldehyde-related stress. Furthermore, heterologous expression of ald1 in Escherichia coli and subsequent in vitro enzyme activity assay demonstrated the oxidation of propionaldehyde and butyraldehyde with different kinetics using either NAD(+) or NADP(+) as cofactors. In addition, overexpression of ald1 in T. vaccinum after Agrobacterium tumefaciens-mediated transformation increased ethanol stress tolerance. These results demonstrate the ability of Ald1 to circumvent ethanol stress, a critical function in mycorrhizal habitats.
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Affiliation(s)
- Theodore Asiimwe
- Institute of Microbiology, Friedrich Schiller University, Neugasse 25, 07743, Jena, Germany
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Meux E, Prosper P, Ngadin A, Didierjean C, Morel M, Dumarçay S, Lamant T, Jacquot JP, Favier F, Gelhaye E. Glutathione transferases of Phanerochaete chrysosporium: S-glutathionyl-p-hydroquinone reductase belongs to a new structural class. J Biol Chem 2011; 286:9162-73. [PMID: 21177852 PMCID: PMC3059006 DOI: 10.1074/jbc.m110.194548] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2010] [Revised: 12/17/2010] [Indexed: 01/24/2023] Open
Abstract
The white rot fungus Phanerochaete chrysosporium, a saprophytic basidiomycete, possesses a large number of cytosolic glutathione transferases, eight of them showing similarity to the Omega class. PcGSTO1 (subclass I, the bacterial homologs of which were recently proposed, based on their enzymatic function, to constitute a new class of glutathione transferase named S-glutathionyl-(chloro)hydroquinone reductases) and PcGSTO3 (subclass II related to mammalian homologs) have been investigated in this study. Biochemical investigations demonstrate that both enzymes are able to catalyze deglutathionylation reactions thanks to the presence of a catalytic cysteinyl residue. This reaction leads to the formation of a disulfide bridge between the conserved cysteine and the removed glutathione from their substrate. The substrate specificity of each isoform differs. In particular PcGSTO1, in contrast to PcGSTO3, was found to catalyze deglutathionylation of S-glutathionyl-p-hydroquinone substrates. The three-dimensional structure of PcGSTO1 presented here confirms the hypothesis that it belongs not only to a new biological class but also to a new structural class that we propose to name GST xi. Indeed, it shows specific features, the most striking ones being a new dimerization mode and a catalytic site that is buried due to the presence of long loops and that contains the catalytic cysteine.
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Affiliation(s)
- Edgar Meux
- From the UMR 1136 INRA-UHP “Interactions Arbres/Micro-Organismes,” IFR110 “Ecosystèmes Forestiers, Agroressources, Bioprocédés et Alimentation,”
| | - Pascalita Prosper
- the CRM2, Equipe Biocristallographie, UMR 7036 CNRS-UHP, Institut Jean Barriol, and
| | - Andrew Ngadin
- From the UMR 1136 INRA-UHP “Interactions Arbres/Micro-Organismes,” IFR110 “Ecosystèmes Forestiers, Agroressources, Bioprocédés et Alimentation,”
| | - Claude Didierjean
- the CRM2, Equipe Biocristallographie, UMR 7036 CNRS-UHP, Institut Jean Barriol, and
| | - Mélanie Morel
- From the UMR 1136 INRA-UHP “Interactions Arbres/Micro-Organismes,” IFR110 “Ecosystèmes Forestiers, Agroressources, Bioprocédés et Alimentation,”
| | - Stéphane Dumarçay
- the Laboratoire d'Études et de Recherches sur le Matériau Bois, EA UHP 4370, Nancy Université, Faculté des Sciences et Techniques, BP 70239, 54506 Vandoeuvre-les-Nancy, France
| | - Tiphaine Lamant
- From the UMR 1136 INRA-UHP “Interactions Arbres/Micro-Organismes,” IFR110 “Ecosystèmes Forestiers, Agroressources, Bioprocédés et Alimentation,”
| | - Jean-Pierre Jacquot
- From the UMR 1136 INRA-UHP “Interactions Arbres/Micro-Organismes,” IFR110 “Ecosystèmes Forestiers, Agroressources, Bioprocédés et Alimentation,”
| | - Frédérique Favier
- the CRM2, Equipe Biocristallographie, UMR 7036 CNRS-UHP, Institut Jean Barriol, and
| | - Eric Gelhaye
- From the UMR 1136 INRA-UHP “Interactions Arbres/Micro-Organismes,” IFR110 “Ecosystèmes Forestiers, Agroressources, Bioprocédés et Alimentation,”
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14
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Chiapello M, Daghino S, Martino E, Perotto S. Cellular response of Fusarium oxysporum to crocidolite asbestos as revealed by a combined proteomic approach. J Proteome Res 2010; 9:3923-31. [PMID: 20578744 DOI: 10.1021/pr100133d] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Cellular mechanisms of asbestos toxicity rely, at least in part, on the chemical composition of these minerals. Iron ions are directly involved in the accepted mechanism of fiber toxicity because they constitute active centers where release of free radicals and reactive oxygen species takes place. Although no current technology is available for the remediation of asbestos polluted sites, the soil fungus Fusarium oxysporum was found to be very effective in iron extraction from crocidolite asbestos in vitro, and to cause a significant reduction in asbestos surface reactivity and oxidative damage to naked DNA. As little information is available on the molecular mechanisms of the fungus-asbestos interactions, a combined proteomic approach that used 2-DE, shotgun and quantitative iTRAQ proteomics was used to investigate the fungal metabolic activities in the presence of crocidolite, an iron-rich type of asbestos. Although global proteomic analyses did not show significant changes in the protein expression pattern of F. oxysporum when exposed to asbestos fibers, some proteins specifically regulated by asbestos suggest up-regulation of metabolic pathways involved in protection from oxidative stress. When compared with the response to crocidolite observed by other authors in human lung epithelial cells, that unlike fungi can internalize the asbestos fibres, a significant difference was the regulation of the pentose phosphate pathway.
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Affiliation(s)
- Marco Chiapello
- Department of Plant Biology, University of Torino, and Institute for Plant Protection CNR, v.le Mattioli 25, Torino, Italy
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15
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Bolchi A, Ruotolo R, Marchini G, Vurro E, di Toppi LS, Kohler A, Tisserant E, Martin F, Ottonello S. Genome-wide inventory of metal homeostasis-related gene products including a functional phytochelatin synthase in the hypogeous mycorrhizal fungus Tuber melanosporum. Fungal Genet Biol 2010; 48:573-84. [PMID: 21094264 DOI: 10.1016/j.fgb.2010.11.003] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2010] [Revised: 10/27/2010] [Accepted: 11/07/2010] [Indexed: 11/27/2022]
Abstract
Ectomycorrhizal fungi are thought to enhance mineral nutrition of their host plants and to confer increased tolerance toward toxic metals. However, a global view of metal homeostasis-related genes and pathways in these organisms is still lacking. Building upon the genome sequence of Tuber melanosporum and on transcriptome analyses, we set out to systematically identify metal homeostasis-related genes in this plant-symbiotic ascomycete. Candidate gene products (101) were subdivided into three major functional classes: (i) metal transport (58); (ii) oxidative stress defence (32); (iii) metal detoxification (11). The latter class includes a small-size metallothionein (TmelMT) that was functionally validated in yeast, and phytochelatin synthase (TmelPCS), the first enzyme of this kind to be described in filamentous ascomycetes. Recombinant TmelPCS was shown to support GSH-dependent, metal-activated phytochelatin synthesis in vitro and to afford increased Cd/Cu tolerance to metal hypersensitive yeast strains. Metal transporters, especially those related to Cu and Zn trafficking, displayed the highest expression levels in mycorrhizae, suggesting extensive translocation of both metals to root cells as well as to fungal metalloenzymes (e.g., laccase) that are strongly upregulated in symbiotic hyphae.
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Affiliation(s)
- Angelo Bolchi
- Department of Biochemistry and Molecular and Functional Biology, University of Parma, 43100 Parma, Italy
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16
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Rouhier N. Plant glutaredoxins: pivotal players in redox biology and iron-sulphur centre assembly. THE NEW PHYTOLOGIST 2010; 186:365-72. [PMID: 20074091 DOI: 10.1111/j.1469-8137.2009.03146.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Glutaredoxins are small oxidoreductases structurally related to thioredoxins. They have two major proposed biochemical roles: the reduction of disulphide bonds and the binding of iron-sulphur clusters, both of which involve glutathione. The thiol-disulphide reductase activity regulates the activity of target proteins, either metabolic enzymes or transcription factors, and also helps to regenerate thiol-dependent antioxidant enzymes, namely thiol-peroxidases and methionine sulphoxide reductases, which are key players for the plant response to environmental constraints. In photosynthetic organisms, glutaredoxins are distributed into six classes. Glutaredoxins from class II can exist either as apoforms, which display deglutathionylation activity, or as holoforms, which bind labile [2Fe-2S] clusters and seem to be required for iron-sulphur cluster assembly. This latter role is supported by the ability of the hologlutaredoxins to rapidly and efficiently transfer their clusters to apo-proteins in vitro. It has been proposed that they can act either as scaffold proteins for the de novo synthesis of iron-sulphur clusters or as carrier proteins for the transfer and delivery of preassembled iron-sulphur clusters.
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Affiliation(s)
- Nicolas Rouhier
- Unité Mixte de Recherches 1136 INRA Nancy University, Interactions Arbre-Microorganismes, IFR 110 EFABA, Faculté des Sciences BP 239, 54506 Vandoeuvre Cedex, France.
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17
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Morel M, Ngadin AA, Droux M, Jacquot JP, Gelhaye E. The fungal glutathione S-transferase system. Evidence of new classes in the wood-degrading basidiomycete Phanerochaete chrysosporium. Cell Mol Life Sci 2009; 66:3711-25. [PMID: 19662500 PMCID: PMC11115709 DOI: 10.1007/s00018-009-0104-5] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2009] [Revised: 07/03/2009] [Accepted: 07/13/2009] [Indexed: 12/13/2022]
Abstract
The recent release of several basidiomycete genome sequences allows an improvement of the classification of fungal glutathione S-transferases (GSTs). GSTs are well-known detoxification enzymes which can catalyze the conjugation of glutathione to non-polar compounds that contain an electrophilic carbon, nitrogen, or sulfur atom. Following this mechanism, they are able to metabolize drugs, pesticides, and many other xenobiotics and peroxides. A genomic and phylogenetic analysis of GST classes in various sequenced fungi--zygomycetes, ascomycetes, and basidiomycetes--revealed some particularities in GST distribution, in comparison with previous analyses with ascomycetes only. By focusing essentially on the wood-degrading basidiomycete Phanerochaete chrysosporium, this analysis highlighted a new fungal GST class named GTE, which is related to bacterial etherases, and two new subclasses of the omega class GSTs. Moreover, our phylogenetic analysis suggests a relationship between the saprophytic behavior of some fungi and the number and distribution of some GST isoforms within specific classes.
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Affiliation(s)
- Mélanie Morel
- IFR 110 Ecosystèmes Forestiers, Agroressources, Bioprocédés et Alimentation, Unité Mixte de Recherches INRA UHP 1136 Interaction Arbres Microorganismes, Université Nancy I BP 239, 54506 Vandoeuvre-lès-Nancy Cedex, France.
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18
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Glutaredoxins: roles in iron homeostasis. Trends Biochem Sci 2009; 35:43-52. [PMID: 19811920 DOI: 10.1016/j.tibs.2009.08.005] [Citation(s) in RCA: 154] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2009] [Revised: 08/04/2009] [Accepted: 08/10/2009] [Indexed: 11/21/2022]
Abstract
Glutaredoxins, proteins traditionally involved in redox reactions, are also required for iron-sulfur cluster assembly and haem biosynthesis. These new roles are probably related to the ability of some glutaredoxins to bind labile [2Fe-2S] clusters and to transfer them rapidly and efficiently to acceptor proteins. Recent results point to putative roles for glutaredoxins in the sensing of cellular iron and in iron-sulfur cluster biogenesis, either as scaffold proteins for the de novo synthesis of iron-sulfur clusters or as carrier proteins for the transfer of preformed iron-sulfur clusters. Based on prokaryote genome analysis and in vivo studies of iron regulation in yeast, we propose putative new roles and binding partners for glutaredoxins in the assembly of metalloproteins.
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Couturier J, Jacquot JP, Rouhier N. Evolution and diversity of glutaredoxins in photosynthetic organisms. Cell Mol Life Sci 2009; 66:2539-57. [PMID: 19506802 PMCID: PMC11115520 DOI: 10.1007/s00018-009-0054-y] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2009] [Revised: 05/06/2009] [Accepted: 05/19/2009] [Indexed: 01/02/2023]
Abstract
The genome sequencing of prokaryotic and eukaryotic photosynthetic organisms enables a comparative genomic study of the glutaredoxin (Grx) family. The analysis of 58 genomes, using a specific motif composed of the active site sequence and of amino acids involved in glutathione binding, led to an updated classification of Grxs into six classes. Only two classes (I and II) are common to all photosynthetic organisms. Eukaryotes and cyanobacteria have two specific Grx classes (classes III and IV and classes V and VI, respectively). The classes IV, V and VI have not yet been identified and contain multimodular Grx fusions. In addition, putative Grx partners were identified from the presence of fusion proteins, the conservation of gene order in bacterial operons, and the gene co-occurrence. The genes encoding class II Grxs and BolA/YrbA proteins are frequently adjacent, in the same transcriptional orientation in prokaryote genomes and present in the same organisms.
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Affiliation(s)
- Jérémy Couturier
- Interactions Arbres Microorganismes, IFR 110 Génomique Ecophysiologie et Ecologie Fonctionnelles, Unité Mixte de Recherches 1136 INRA-Nancy Université, 54506 Vandoeuvre-lès-Nancy Cedex, France
| | - Jean-Pierre Jacquot
- Interactions Arbres Microorganismes, IFR 110 Génomique Ecophysiologie et Ecologie Fonctionnelles, Unité Mixte de Recherches 1136 INRA-Nancy Université, 54506 Vandoeuvre-lès-Nancy Cedex, France
| | - Nicolas Rouhier
- Interactions Arbres Microorganismes, IFR 110 Génomique Ecophysiologie et Ecologie Fonctionnelles, Unité Mixte de Recherches 1136 INRA-Nancy Université, 54506 Vandoeuvre-lès-Nancy Cedex, France
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20
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Couturier J, Koh CS, Zaffagnini M, Winger AM, Gualberto JM, Corbier C, Decottignies P, Jacquot JP, Lemaire SD, Didierjean C, Rouhier N. Structure-function relationship of the chloroplastic glutaredoxin S12 with an atypical WCSYS active site. J Biol Chem 2009; 284:9299-310. [PMID: 19158074 PMCID: PMC2666582 DOI: 10.1074/jbc.m807998200] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2008] [Revised: 01/16/2009] [Indexed: 01/08/2023] Open
Abstract
Glutaredoxins (Grxs) are efficient catalysts for the reduction of mixed disulfides in glutathionylated proteins, using glutathione or thioredoxin reductases for their regeneration. Using GFP fusion, we have shown that poplar GrxS12, which possesses a monothiol (28)WCSYS(32) active site, is localized in chloroplasts. In the presence of reduced glutathione, the recombinant protein is able to reduce in vitro substrates, such as hydroxyethyldisulfide and dehydroascorbate, and to regenerate the glutathionylated glyceraldehyde-3-phosphate dehydrogenase. Although the protein possesses two conserved cysteines, it is functioning through a monothiol mechanism, the conserved C terminus cysteine (Cys(87)) being dispensable, since the C87S variant is fully active in all activity assays. Biochemical and crystallographic studies revealed that Cys(87) exhibits a certain reactivity, since its pK(a) is around 5.6. Coupled with thiol titration, fluorescence, and mass spectrometry analyses, the resolution of poplar GrxS12 x-ray crystal structure shows that the only oxidation state is a glutathionylated derivative of the active site cysteine (Cys(29)) and that the enzyme does not form inter- or intramolecular disulfides. Contrary to some plant Grxs, GrxS12 does not incorporate an iron-sulfur cluster in its wild-type form, but when the active site is mutated into YCSYS, it binds a [2Fe-2S] cluster, indicating that the single Trp residue prevents this incorporation.
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Affiliation(s)
- Jeremy Couturier
- Unité Mixte de Recherches 1136 UHP-INRA Interaction Arbres-Microorganismes, IFR 110 GEEF, Nancy Université, Faculté des Sciences, 54506 Vandoeuvre Cedex, France
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21
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Abstract
The first genomic sequence for a representative of symbiotic fungi, the ectomycorrhizal basidiomycete Laccaria bicolor, has been published. The unravelling of this genome provides tantalizing hints about differences between this symbiotic fungus and its saprotrophic and pathogenic relatives. An expansion of several multigene families occurred in L. bicolor, suggesting that adaptation to symbiosis proceeded by gene duplication. Within lineage-specific genes those coding for symbiosis-regulated secreted proteins showed an up-regulated expression in ectomycorrhizas. L. bicolor is lacking enzymes involved in the degradation of plant cell wall components (cellulose, hemicellulose, pectins and pectates), preventing the symbiont from degrading host cells. By contrast, L. bicolor possesses expanded multigene families associated with hydrolysis of bacterial and microfauna polysaccharides and proteins. The genome analysis revealed the dual saprotrophic and biotrophic lifestyle of the mycorrhizal fungus that enables it to grow within both soil and living plant roots. The next stages will involve finer-scale investigation of gene networks to reveal the details of the general patterns now uncovered at the genomic level. The acceptance of L. bicolor as a model organism for symbiosis genetics will, however, depend strongly on the availability of additional genetic, genomic and molecular biological resources, such as gene inactivation procedures.
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Affiliation(s)
- Francis Martin
- UMR1136 INRA-Nancy Université Interactions Arbres/Micro-organismes, IFR110, Centre de Nancy, 54280 Champenoux, France
| | - Marc-André Selosse
- UMR5175, Centre d'Ecologie Fonctionnelle et Evolutive, Equipe Interactions Biotiques, 1919 Route de Mende, 34 293 Montpellier cedex 5, France
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Talbot NJ. Unwrapping the Laccaria genome. THE NEW PHYTOLOGIST 2008; 180:259-260. [PMID: 19138214 DOI: 10.1111/j.1469-8137.2008.02636.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
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