1
|
João JMLG, Silva Barbosa JA, Sales da Silva LL, Fukuzaki S, de Campos EC, Camargo LDN, dos Santos TM, Moreira Bezerra SK, de Almeida FM, Saraiva-Romanholo BM, Lopes FDTQDS, Bonturi CR, Righetti RF, Oliva MLV, Tibério IDFLC, Leick EA. Effects of plant protease inhibitors (Pep-3-EcTI, Pep-BbKI, and Pep-BrTI) versus corticosteroids on inflammation, remodeling, and oxidative stress in an asthma-COPD (ACO) model. Front Pharmacol 2024; 15:1282870. [PMID: 38774212 PMCID: PMC11106483 DOI: 10.3389/fphar.2024.1282870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Accepted: 03/08/2024] [Indexed: 05/24/2024] Open
Abstract
The peptide derived from E. contortisiliquum trypsin inhibitor (Pep-3-EcTI), peptide derived from kallikrein inhibitor isolated from B. bauhinioides (Pep-BbKI), and B. rufa peptide modified from B. bauhinioides (Pep-BrTI) peptides exhibit anti-inflammatory and antioxidant activities, suggesting their potential for treating asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO). We compared the effects of these peptides with dexamethasone (DX) treatment in an ACO model. In this study, 11 groups of male BALB/c mice were pre-treated under different conditions, including sensitization with intraperitoneal injection and inhalation of ovalbumin (OVA), intratracheal instillation of porcine pancreatic elastase (ELA), sensitization with intraperitoneal injection, and various combinations of peptide treatments with Pep-3-EcTI, Pep-BbKI, Pep-BrTI, dexamethasone, and non-treated controls (SAL-saline). Respiratory system resistance, airway resistance, lung tissue resistance, exhaled nitric oxide, linear mean intercept, immune cell counts in the bronchoalveolar lavage fluid, cytokine expression, extracellular matrix remodeling, and oxidative stress in the airways and alveolar septa were evaluated on day 28. Results showed increased respiratory parameters, inflammatory markers, and tissue remodeling in the ACO group compared to controls. Treatment with the peptides or DX attenuated or reversed these responses, with the peptides showing effectiveness in controlling hyperresponsiveness, inflammation, remodeling, and oxidative stress markers. These peptides demonstrated an efficacy comparable to that of corticosteroids in the ACO model. However, this study highlights the need for further research to assess their safety, mechanisms of action, and potential translation to clinical studies before considering these peptides for human use.
Collapse
Affiliation(s)
| | | | | | - Silvia Fukuzaki
- Faculdade de Medicina FMUSP, Universidade de São Paulo, São Paulo, Brazil
| | | | | | | | | | | | | | | | - Camila Ramalho Bonturi
- Departamento de Bioquímica, Universidade Federal de Sao Paulo (UNIFESP), São Paulo, Brazil
| | - Renato Fraga Righetti
- Faculdade de Medicina FMUSP, Universidade de São Paulo, São Paulo, Brazil
- Hospital Sírio-Libanês, São Paulo, Brazil
| | | | | | | |
Collapse
|
2
|
Teo YX, Lee KY, Goh CJH, Wang LC, Sobota RM, Chiam KH, Du C, Wan ACA. Fungus-derived protein particles as cell-adhesive matrices for cell-cultivated food. NPJ Sci Food 2023; 7:34. [PMID: 37443321 DOI: 10.1038/s41538-023-00209-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 06/27/2023] [Indexed: 07/15/2023] Open
Abstract
Cell-adhesive factors mediate adhesion of cells to substrates via peptide motifs such as the Arg-Gly-Asp (RGD) sequence. With the onset of sustainability issues, there is a pressing need to find alternatives to animal-derived cell-adhesive factors, especially for cell-cultivated food applications. In this paper, we show how data mining can be a powerful approach toward identifying fungal-derived cell-adhesive proteins and present a method to isolate and utilize these proteins as extracellular matrices (ECM) to support cell adhesion and culture in 3D. Screening of a protein database for fungal and plant proteins uncovered that ~5.5% of the unique reported proteins contain RGD sequences. A plot of fungi species vs RGD percentage revealed that 98% of the species exhibited an RGD percentage > = 1%. We observed the formation of protein particles in crude extracts isolated from basidiomycete fungi, which could be correlated to their stability towards particle aggregation at different temperatures. These protein particles were incorporated in 3D fiber matrices encapsulating mouse myoblast cells, showing a positive effect on cell alignment. We demonstrated a cell traction stress on the protein particles (from Flammulina velutipes) that was comparable to cells on fibronectin. A snapshot of the RGD-containing proteins in the fungal extracts was obtained by combining SDS-PAGE and mass spectrometry of the peptide fragments obtained by enzymatic cleavage. Therefore, a sustainable source of cell-adhesive proteins is widely available in the fungi kingdom. A method has been developed to identify candidate species and produce cell-adhesive matrices, applicable to the cell-cultivated food and healthcare industries.
Collapse
Affiliation(s)
- Yu Xing Teo
- Singapore Institute of Food and Biotechnology Innovation, Agency for Science, Technology, and Research (A*STAR), Singapore, 138669, Singapore
| | - Kah Yin Lee
- Singapore Institute of Food and Biotechnology Innovation, Agency for Science, Technology, and Research (A*STAR), Singapore, 138669, Singapore
| | - Corinna Jie Hui Goh
- Bioinformatics Institute, Agency for Science, Technology, and Research (A*STAR), Singapore, 138671, Singapore
| | - Loo Chien Wang
- Functional Proteomics Laboratory, SingMass National Laboratory, Institute of Molecular and Cell Biology, Agency for Science, Technology, and Research (A*STAR), Singapore, 138673, Singapore
| | - Radoslaw M Sobota
- Functional Proteomics Laboratory, SingMass National Laboratory, Institute of Molecular and Cell Biology, Agency for Science, Technology, and Research (A*STAR), Singapore, 138673, Singapore
| | - Keng-Hwee Chiam
- Bioinformatics Institute, Agency for Science, Technology, and Research (A*STAR), Singapore, 138671, Singapore
| | - Chan Du
- Singapore Institute of Food and Biotechnology Innovation, Agency for Science, Technology, and Research (A*STAR), Singapore, 138669, Singapore.
| | - Andrew C A Wan
- Singapore Institute of Food and Biotechnology Innovation, Agency for Science, Technology, and Research (A*STAR), Singapore, 138669, Singapore.
| |
Collapse
|
3
|
Tiwari N, Kumari A, Uttam G, Singh V, Singh K, Katiyar D. Synthesis and Antifungal Activity of Some Novel Coumarin‐Amino Acid Conjugates. ChemistrySelect 2022. [DOI: 10.1002/slct.202201299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Neha Tiwari
- Department of Chemistry MMV Banaras Hindu University Varanasi 221005 India
| | - Ankita Kumari
- Department of Zoology MMV Banaras Hindu University Varanasi 221005 India
| | - Gunjan Uttam
- Department of Zoology MMV Banaras Hindu University Varanasi 221005 India
| | - Vineeta Singh
- Department of Biotechnology Institute of Engineering and Technology Sitapur Road Lucknow 226021 India
| | - Karuna Singh
- Department of Zoology MMV Banaras Hindu University Varanasi 221005 India
| | - Diksha Katiyar
- Department of Chemistry MMV Banaras Hindu University Varanasi 221005 India
| |
Collapse
|
4
|
Kumari A, Tripathi AH, Gautam P, Gahtori R, Pande A, Singh Y, Madan T, Upadhyay SK. Adhesins in the virulence of opportunistic fungal pathogens of human. Mycology 2021; 12:296-324. [PMID: 34900383 PMCID: PMC8654403 DOI: 10.1080/21501203.2021.1934176] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Aspergillosis, candidiasis, and cryptococcosis are the most common cause of mycoses-related disease and death among immune-compromised patients. Adhesins are cell-surface exposed proteins or glycoproteins of pathogens that bind to the extracellular matrix (ECM) constituents or mucosal epithelial surfaces of the host cells. The forces of interaction between fungal adhesins and host tissues are accompanied by ligand binding, hydrophobic interactions and protein-protein aggregation. Adherence is the primary and critical step involved in the pathogenesis; however, there is limited information on fungal adhesins compared to that on the bacterial adhesins. Except a few studies based on screening of proteome for adhesin identification, majority are based on characterization of individual adhesins. Recently, based on their characteristic signatures, many putative novel fungal adhesins have been predicted using bioinformatics algorithms. Some of these novel adhesin candidates have been validated by in-vitro studies; though, most of them are yet to be characterised experimentally. Morphotype specific adhesin expression as well as tissue tropism are the crucial determinants for a successful adhesion process. This review presents a comprehensive overview of various studies on fungal adhesins and discusses the targetability of the adhesins and adherence phenomenon, for combating the fungal infection in a preventive or therapeutic mode.
Collapse
Affiliation(s)
- Amrita Kumari
- Department of Biotechnology, Sir J.C. Bose Technical campus, Kumaun University, Nainital, India
| | - Ankita H Tripathi
- Department of Biotechnology, Sir J.C. Bose Technical campus, Kumaun University, Nainital, India
| | - Poonam Gautam
- ICMR-National Institute of Pathology, New Delhi, India
| | - Rekha Gahtori
- Department of Biotechnology, Sir J.C. Bose Technical campus, Kumaun University, Nainital, India
| | - Amit Pande
- Directorate of Coldwater Fisheries Research (DCFR), Nainital, India
| | - Yogendra Singh
- Department of Zoology, University of Delhi, New Delhi, India
| | - Taruna Madan
- ICMR-National Institute for Research in Reproductive Health (NIRRH), Mumbai, India
| | - Santosh K Upadhyay
- Department of Biotechnology, Sir J.C. Bose Technical campus, Kumaun University, Nainital, India
| |
Collapse
|
5
|
Bui TT, Harting R, Braus-Stromeyer SA, Tran VT, Leonard M, Höfer A, Abelmann A, Bakti F, Valerius O, Schlüter R, Stanley CE, Ambrósio A, Braus GH. Verticillium dahliae transcription factors Som1 and Vta3 control microsclerotia formation and sequential steps of plant root penetration and colonisation to induce disease. THE NEW PHYTOLOGIST 2019; 221:2138-2159. [PMID: 30290010 DOI: 10.1111/nph.15514] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 09/26/2018] [Indexed: 06/08/2023]
Abstract
Verticillium dahliae nuclear transcription factors Som1 and Vta3 can rescue adhesion in a FLO8-deficient Saccharomyces cerevisiae strain. Som1 and Vta3 induce the expression of the yeast FLO1 and FLO11 genes encoding adhesins. Som1 and Vta3 are sequentially required for root penetration and colonisation of the plant host by V. dahliae. The SOM1 and VTA3 genes were deleted and their functions in fungus-induced plant pathogenesis were studied using genetic, cell biology, proteomic and plant pathogenicity experiments. Som1 supports fungal adhesion and root penetration and is required earlier than Vta3 in the colonisation of plant root surfaces and tomato plant infection. Som1 controls septa positioning and the size of vacuoles, and subsequently hyphal development including aerial hyphae formation and normal hyphal branching. Som1 and Vta3 control conidiation, microsclerotia formation, and antagonise in oxidative stress responses. The molecular function of Som1 is conserved between the plant pathogen V. dahliae and the opportunistic human pathogen Aspergillus fumigatus. Som1 controls genes for initial steps of plant root penetration, adhesion, oxidative stress response and VTA3 expression to allow subsequent root colonisation. Both Som1 and Vta3 regulate developmental genetic networks required for conidiation, microsclerotia formation and pathogenicity of V. dahliae.
Collapse
Affiliation(s)
- Tri-Thuc Bui
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, University of Goettingen and Goettingen Center for Molecular Biosciences (GZMB), Grisebachstr. 8, D-37077, Goettingen, Germany
| | - Rebekka Harting
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, University of Goettingen and Goettingen Center for Molecular Biosciences (GZMB), Grisebachstr. 8, D-37077, Goettingen, Germany
| | - Susanna A Braus-Stromeyer
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, University of Goettingen and Goettingen Center for Molecular Biosciences (GZMB), Grisebachstr. 8, D-37077, Goettingen, Germany
| | - Van-Tuan Tran
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, University of Goettingen and Goettingen Center for Molecular Biosciences (GZMB), Grisebachstr. 8, D-37077, Goettingen, Germany
- Department of Microbiology, Faculty of Biology, VNU University of Science, 334 Nguyen Trai, Thanh Xuan, 100000, Hanoi, Vietnam
| | - Miriam Leonard
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, University of Goettingen and Goettingen Center for Molecular Biosciences (GZMB), Grisebachstr. 8, D-37077, Goettingen, Germany
| | - Annalena Höfer
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, University of Goettingen and Goettingen Center for Molecular Biosciences (GZMB), Grisebachstr. 8, D-37077, Goettingen, Germany
| | - Anja Abelmann
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, University of Goettingen and Goettingen Center for Molecular Biosciences (GZMB), Grisebachstr. 8, D-37077, Goettingen, Germany
| | - Fruzsina Bakti
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, University of Goettingen and Goettingen Center for Molecular Biosciences (GZMB), Grisebachstr. 8, D-37077, Goettingen, Germany
| | - Oliver Valerius
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, University of Goettingen and Goettingen Center for Molecular Biosciences (GZMB), Grisebachstr. 8, D-37077, Goettingen, Germany
| | - Rabea Schlüter
- Imaging Center of the Department of Biology, University of Greifswald, D-17489, Greifswald, Germany
| | - Claire E Stanley
- Plant-Soil Interactions, Agroecology and Environment Research Division, Agroscope, Reckenholzstrasse 191, CH-8046, Zürich, Switzerland
| | - Alinne Ambrósio
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, University of Goettingen and Goettingen Center for Molecular Biosciences (GZMB), Grisebachstr. 8, D-37077, Goettingen, Germany
| | - Gerhard H Braus
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, University of Goettingen and Goettingen Center for Molecular Biosciences (GZMB), Grisebachstr. 8, D-37077, Goettingen, Germany
| |
Collapse
|
6
|
Tröster V, Setzer T, Hirth T, Pecina A, Kortekamp A, Nick P. Probing the contractile vacuole as Achilles' heel of the biotrophic grapevine pathogen Plasmopara viticola. PROTOPLASMA 2017; 254:1887-1901. [PMID: 28550468 DOI: 10.1007/s00709-017-1123-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 05/10/2017] [Indexed: 05/20/2023]
Abstract
The causative agent of Grapevine Downy Mildew, the oomycete Plasmopara viticola, poses a serious threat to viticulture. In the current work, the contractile vacuole of the zoospore is analysed as potential target for novel plant protection strategies. Using a combination of electron microscopy, spinning disc confocal microscopy, and video differential interference contrast microscopy, we have followed the genesis and dynamics of this vacuole required during the search for the stomata, when the non-walled zoospore is exposed to hypotonic conditions. This subcellular description was combined with a pharmacological study, where the functionality of the contractile vacuole was blocked by manipulation of actin, by Na, Cu, and Al ions or by inhibition of the NADPH oxidase. We further observe that RGD peptides (mimicking binding sites for integrins at the extracellular matrix) can inhibit the function of the contractile vacuole as well. Finally, we show that an extract from Chinese liquorice (Glycyrrhiza uralensis) proposed as biocontrol for Downy Mildews can efficiently induce zoospore burst and that this activity depends on the activity of NADPH oxidase. The effect of the extract can be phenocopied by its major compound, glycyrrhizin, suggesting a mode of action for this biologically safe alternative to copper products.
Collapse
Affiliation(s)
- Viktoria Tröster
- Molecular Cell Biology, Botanical Institute Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 4, Bld. 30.43, 76131, Karlsruhe, Germany
| | - Tabea Setzer
- Molecular Cell Biology, Botanical Institute Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 4, Bld. 30.43, 76131, Karlsruhe, Germany
| | - Thomas Hirth
- Molecular Cell Biology, Botanical Institute Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 4, Bld. 30.43, 76131, Karlsruhe, Germany
| | - Anna Pecina
- Molecular Cell Biology, Botanical Institute Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 4, Bld. 30.43, 76131, Karlsruhe, Germany
| | - Andreas Kortekamp
- Institute of Plant Protection State Education and Research Center (DLR) Rheinpfalz, Breitenweg 71, 67435, Neustadt, Germany
| | - Peter Nick
- Molecular Cell Biology, Botanical Institute Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 4, Bld. 30.43, 76131, Karlsruhe, Germany.
| |
Collapse
|
7
|
Fan R, Klosterman SJ, Wang C, Subbarao KV, Xu X, Shang W, Hu X. Vayg1 is required for microsclerotium formation and melanin production in Verticillium dahliae. Fungal Genet Biol 2017; 98:1-11. [DOI: 10.1016/j.fgb.2016.11.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Revised: 10/11/2016] [Accepted: 11/16/2016] [Indexed: 11/24/2022]
|
8
|
Liu C, Zhang T, Wang L, Wang M, Wang W, Jia Z, Jiang S, Song L. The modulation of extracellular superoxide dismutase in the specifically enhanced cellular immune response against secondary challenge of Vibrio splendidus in Pacific oyster (Crassostrea gigas). DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2016; 63:163-170. [PMID: 27268574 DOI: 10.1016/j.dci.2016.06.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Revised: 06/01/2016] [Accepted: 06/02/2016] [Indexed: 06/06/2023]
Abstract
Extracellular superoxide dismutase (EcSOD) is a copper-containing glycoprotein playing an important role in antioxidant defense of living cells exposed to oxidative stress, and also participating in microorganism internalization and cell adhesion in invertebrates. EcSOD from oyster (designated CgEcSOD) had been previously reported to bind lipopolysaccharides (LPS) and act as a bridge molecule in Vibrio splendidus internalization. Its mRNA expression pattern, PAMP binding spectrum and microorganism binding capability were examined in the present study. The mRNA expression of CgEcSOD in hemocytes was significantly up-regulated at the initial phase and decreased sharply at 48 h post V. splendidus stimulation. The recombinant CgEcSOD protein (rCgEcSOD) could bind LPS, PGN and poly (I:C), as well as various microorganisms including Micrococcus luteus, Staphylococcus aureus, Escherichia coli, Vibrio anguillarum, V. splendidus, Pastoris pastoris and Yarrowia lipolytica at the presence of divalent metal ions Cu(2+). After the secondary V. splendidus stimulation, the mRNA and protein of CgEcSOD were both down-regulated significantly. The results collectively indicated that CgEcSOD could not only function in the immune recognition, but also might contribute to the immune priming of oyster by inhibiting the foreign microbe invasion through a specific down-regulation.
Collapse
Affiliation(s)
- Conghui Liu
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tao Zhang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lingling Wang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Mengqiang Wang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Weilin Wang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhihao Jia
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shuai Jiang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Linsheng Song
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture, Dalian Ocean University, Dalian 116023, China.
| |
Collapse
|
9
|
Novel Aggregation Properties of Candida albicans Secreted Aspartyl Proteinase Sap6 Mediate Virulence in Oral Candidiasis. Infect Immun 2015; 83:2614-26. [PMID: 25870228 DOI: 10.1128/iai.00282-15] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Candida albicans, a commensal fungus of the oral microbiome, causes oral candidiasis in humans with localized or systemic immune deficiencies. Secreted aspartic proteinases (Saps) are a family of 10 related proteases and are virulence factors due to their proteolytic activity, as well as their roles in adherence and colonization of host tissues. We found that mice infected sublingually with C. albicans cells overexpressing Sap6 (SAP6 OE and a Δsap8 strain) had thicker fungal plaques and more severe oral infection, while infection with the Δsap6 strain was attenuated. These hypervirulent strains had highly aggregative colony structure in vitro and higher secreted proteinase activity; however, the levels of proteinase activity of C. albicans Saps did not uniformly match their abilities to damage cultured oral epithelial cells (SCC-15 cells). Hyphal induction in cells overexpressing Sap6 (SAP6 OE and Δsap8 cells) resulted in formation of large cell-cell aggregates. These aggregates could be produced in germinated wild-type cells by addition of native or heat-inactivated Sap6. Sap6 bound only to germinated cells and increased C. albicans adhesion to oral epithelial cells. The adhesion properties of Sap6 were lost upon deletion of its integrin-binding motif (RGD) and could be inhibited by addition of RGD peptide or anti-integrin antibodies. Thus, Sap6 (but not Sap5) has an alternative novel function in cell-cell aggregation, independent of its proteinase activity, to promote infection and virulence in oral candidiasis.
Collapse
|
10
|
Lang I, Sassmann S, Schmidt B, Komis G. Plasmolysis: Loss of Turgor and Beyond. PLANTS (BASEL, SWITZERLAND) 2014; 3:583-93. [PMID: 27135521 PMCID: PMC4844282 DOI: 10.3390/plants3040583] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Revised: 10/15/2014] [Accepted: 11/14/2014] [Indexed: 11/17/2022]
Abstract
Plasmolysis is a typical response of plant cells exposed to hyperosmotic stress. The loss of turgor causes the violent detachment of the living protoplast from the cell wall. The plasmolytic process is mainly driven by the vacuole. Plasmolysis is reversible (deplasmolysis) and characteristic to living plant cells. Obviously, dramatic structural changes are required to fulfill a plasmolytic cycle. In the present paper, the fate of cortical microtubules and actin microfilaments is documented throughout a plasmolytic cycle in living cells of green fluorescent protein (GFP) tagged Arabidopsis lines. While the microtubules became wavy and highly bundled during plasmolysis, cortical filamentous actin remained in close vicinity to the plasma membrane lining the sites of concave plasmolysis and adjusting readily to the diminished size of the protoplast. During deplasmolysis, cortical microtubule re-organization progressed slowly and required up to 24 h to complete the restoration of the original pre-plasmolytic pattern. Actin microfilaments, again, recovered faster and organelle movement remained intact throughout the whole process. In summary, the hydrostatic skeleton resulting from the osmotic state of the plant vacuole "overrules" the stabilization by cortical cytoskeletal elements.
Collapse
Affiliation(s)
- Ingeborg Lang
- Cell Imaging and Ultrastructure Research, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria.
| | - Stefan Sassmann
- Cell Imaging and Ultrastructure Research, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria.
| | - Brigitte Schmidt
- Cell Imaging and Ultrastructure Research, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria.
| | - George Komis
- CR-Hana, Palacký University Olomouc, Šlechtitelů 586/11, 783 71 Olomouc-Holice, Czech Republic.
| |
Collapse
|
11
|
Tran VT, Braus-Stromeyer SA, Kusch H, Reusche M, Kaever A, Kühn A, Valerius O, Landesfeind M, Aßhauer K, Tech M, Hoff K, Pena-Centeno T, Stanke M, Lipka V, Braus GH. Verticillium transcription activator of adhesion Vta2 suppresses microsclerotia formation and is required for systemic infection of plant roots. THE NEW PHYTOLOGIST 2014; 202:565-581. [PMID: 24433459 DOI: 10.1111/nph.12671] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Accepted: 12/03/2013] [Indexed: 05/05/2023]
Abstract
Six transcription regulatory genes of the Verticillium plant pathogen, which reprogrammed nonadherent budding yeasts for adhesion, were isolated by a genetic screen to identify control elements for early plant infection. Verticillium transcription activator of adhesion Vta2 is highly conserved in filamentous fungi but not present in yeasts. The Magnaporthe grisea ortholog conidiation regulator Con7 controls the formation of appressoria which are absent in Verticillium species. Vta2 was analyzed by using genetics, cell biology, transcriptomics, secretome proteomics and plant pathogenicity assays. Nuclear Vta2 activates the expression of the adhesin-encoding yeast flocculin genes FLO1 and FLO11. Vta2 is required for fungal growth of Verticillium where it is a positive regulator of conidiation. Vta2 is mandatory for accurate timing and suppression of microsclerotia as resting structures. Vta2 controls expression of 270 transcripts, including 10 putative genes for adhesins and 57 for secreted proteins. Vta2 controls the level of 125 secreted proteins, including putative adhesins or effector molecules and a secreted catalase-peroxidase. Vta2 is a major regulator of fungal pathogenesis, and controls host-plant root infection and H2 O2 detoxification. Verticillium impaired in Vta2 is unable to colonize plants and induce disease symptoms. Vta2 represents an interesting target for controlling the growth and development of these vascular pathogens.
Collapse
Affiliation(s)
- Van-Tuan Tran
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, Georg-August-University Göttingen, Grisebachstr. 8, D-37077, Göttingen, Germany
- Department of Microbiology, Faculty of Biology, VNU University of Science, 334 Nguyen Trai, Thanh Xuan, Hanoi, Vietnam
| | - Susanna A Braus-Stromeyer
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, Georg-August-University Göttingen, Grisebachstr. 8, D-37077, Göttingen, Germany
| | - Harald Kusch
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, Georg-August-University Göttingen, Grisebachstr. 8, D-37077, Göttingen, Germany
| | - Michael Reusche
- Department of Plant Cell Biology, Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-University Göttingen, Julia-Lermontowa-Weg 3, D-37077, Göttingen, Germany
| | - Alexander Kaever
- Department of Bioinformatics, Institute of Microbiology and Genetics, Georg-August-University Göttingen, Goldschmidtstr. 1, D-37077, Göttingen, Germany
| | - Anika Kühn
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, Georg-August-University Göttingen, Grisebachstr. 8, D-37077, Göttingen, Germany
| | - Oliver Valerius
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, Georg-August-University Göttingen, Grisebachstr. 8, D-37077, Göttingen, Germany
| | - Manuel Landesfeind
- Department of Bioinformatics, Institute of Microbiology and Genetics, Georg-August-University Göttingen, Goldschmidtstr. 1, D-37077, Göttingen, Germany
| | - Kathrin Aßhauer
- Department of Bioinformatics, Institute of Microbiology and Genetics, Georg-August-University Göttingen, Goldschmidtstr. 1, D-37077, Göttingen, Germany
| | - Maike Tech
- Department of Bioinformatics, Institute of Microbiology and Genetics, Georg-August-University Göttingen, Goldschmidtstr. 1, D-37077, Göttingen, Germany
| | - Katharina Hoff
- Institute for Mathematics and Computer Science, Ernst-Moritz-Arndt-University Greifswald, Walther-Rathenau-Straße 47, D-17487, Greifswald, Germany
| | - Tonatiuh Pena-Centeno
- Institute for Mathematics and Computer Science, Ernst-Moritz-Arndt-University Greifswald, Walther-Rathenau-Straße 47, D-17487, Greifswald, Germany
| | - Mario Stanke
- Institute for Mathematics and Computer Science, Ernst-Moritz-Arndt-University Greifswald, Walther-Rathenau-Straße 47, D-17487, Greifswald, Germany
| | - Volker Lipka
- Department of Plant Cell Biology, Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-University Göttingen, Julia-Lermontowa-Weg 3, D-37077, Göttingen, Germany
| | - Gerhard H Braus
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics, Georg-August-University Göttingen, Grisebachstr. 8, D-37077, Göttingen, Germany
| |
Collapse
|
12
|
García-Linares S, Richmond R, García-Mayoral MF, Bustamante N, Bruix M, Gavilanes JG, Martínez-del-Pozo Á. The sea anemone actinoporin (Arg-Gly-Asp) conserved motif is involved in maintaining the competent oligomerization state of these pore-forming toxins. FEBS J 2014; 281:1465-1478. [DOI: 10.1111/febs.12717] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 12/12/2013] [Accepted: 12/31/2013] [Indexed: 01/19/2023]
Affiliation(s)
- Sara García-Linares
- Departamento de Bioquímica y Biología Molecular I; Facultad de Ciencias Químicas; Universidad Complutense; Madrid Spain
| | - Ryan Richmond
- Departamento de Bioquímica y Biología Molecular I; Facultad de Ciencias Químicas; Universidad Complutense; Madrid Spain
| | | | | | - Marta Bruix
- Instituto de Química-Física Rocasolano; Madrid Spain
| | - José G. Gavilanes
- Departamento de Bioquímica y Biología Molecular I; Facultad de Ciencias Químicas; Universidad Complutense; Madrid Spain
| | - Álvaro Martínez-del-Pozo
- Departamento de Bioquímica y Biología Molecular I; Facultad de Ciencias Químicas; Universidad Complutense; Madrid Spain
| |
Collapse
|
13
|
Cavazzini D, Meschi F, Corsini R, Bolchi A, Rossi GL, Einsle O, Ottonello S. Autoproteolytic Activation of a Symbiosis-regulated Truffle Phospholipase A2. J Biol Chem 2012. [PMID: 23192346 DOI: 10.1074/jbc.m112.384156] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Fungal phospholipases are members of the fungal/bacterial group XIV secreted phospholipases A(2) (sPLA(2)s). TbSP1, the sPLA(2) primarily addressed in this study, is up-regulated by nutrient deprivation and is preferentially expressed in the symbiotic stage of the ectomycorrhizal fungus Tuber borchii. A peculiar feature of this phospholipase and of its ortholog from the black truffle Tuber melanosporum is the presence of a 54-amino acid sequence of unknown functional significance, interposed between the signal peptide and the start of the conserved catalytic core of the enzyme. X-ray diffraction analysis of a recombinant TbSP1 form corresponding to the secreted protein previously identified in T. borchii mycelia revealed a structure comprising the five α-helices that form the phospholipase catalytic module but lacking the N-terminal 54 amino acids. This finding led to a series of functional studies that showed that TbSP1, as well as its T. melanosporum ortholog, is a self-processing pro-phospholipase A(2), whose phospholipase activity increases up to 80-fold following autoproteolytic removal of the N-terminal peptide. Proteolytic cleavage occurs within a serine-rich, intrinsically flexible region of TbSP1, does not involve the phospholipase active site, and proceeds via an intermolecular mechanism. Autoproteolytic activation, which also takes place at the surface of nutrient-starved, sPLA(2) overexpressing hyphae, may strengthen and further control the effects of phospholipase up-regulation in response to nutrient deprivation, also in the context of symbiosis establishment and mycorrhiza formation.
Collapse
Affiliation(s)
- Davide Cavazzini
- Laboratory of Functional Genomics and Protein Engineering, Biochemistry and Molecular Biology Unit, Department of Biosciences, University of Parma, Parco Area delle Scienze 23/A, I-43124 Parma, Italy
| | | | | | | | | | | | | |
Collapse
|
14
|
Bouwmeester K, de Sain M, Weide R, Gouget A, Klamer S, Canut H, Govers F. The lectin receptor kinase LecRK-I.9 is a novel Phytophthora resistance component and a potential host target for a RXLR effector. PLoS Pathog 2011; 7:e1001327. [PMID: 21483488 PMCID: PMC3068997 DOI: 10.1371/journal.ppat.1001327] [Citation(s) in RCA: 166] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2010] [Accepted: 02/28/2011] [Indexed: 12/03/2022] Open
Abstract
In plants, an active defense against biotrophic pathogens is dependent on a functional continuum between the cell wall (CW) and the plasma membrane (PM). It is thus anticipated that proteins maintaining this continuum also function in defense. The legume-like lectin receptor kinase LecRK-I.9 is a putative mediator of CW-PM adhesions in Arabidopsis and is known to bind in vitro to the Phytophthora infestans RXLR-dEER effector IPI-O via a RGD cell attachment motif present in IPI-O. Here we show that LecRK-I.9 is associated with the plasma membrane, and that two T-DNA insertions lines deficient in LecRK-I.9 (lecrk-I.9) have a ‘gain-of-susceptibility’ phenotype specifically towards the oomycete Phytophthora brassicae. Accordingly, overexpression of LecRK-I.9 leads to enhanced resistance to P. brassicae. A similar ‘gain-of-susceptibility’ phenotype was observed in transgenic Arabidopsis lines expressing ipiO (35S-ipiO1). This phenocopy behavior was also observed with respect to other defense-related functions; lecrk-I.9 and 35S-ipiO1 were both disturbed in pathogen- and MAMP-triggered callose deposition. By site-directed mutagenesis, we demonstrated that the RGD cell attachment motif in IPI-O is not only essential for disrupting the CW-PM adhesions, but also for disease suppression. These results suggest that destabilizing the CW-PM continuum is one of the tactics used by Phytophthora to promote infection. As countermeasure the host may want to strengthen CW-PM adhesions and the novel Phytophthora resistance component LecRK-I.9 seems to function in this process. Phytophthora species are notorious plant pathogens which cause a variety of devastating crop diseases. Phytophthora pathogens secrete a plethora of effector proteins, several of which are known to interact with receptors in the host cell thereby either activating or suppressing defense responses. Unlike animals, plants lack an adaptive immune system; however, they are not defenseless and have acquired other mechanisms to withstand pathogens. Receptor proteins play important roles in sensing alterations at the plant cell wall and in mediating responses upon pathogen attack. This paper focuses on the Arabidopsis lectin receptor kinase LecRK-I.9, a mediator of cell wall – plasma membrane (CW-PM) adhesions that is known to bind in vitro to the Phytophthora infestans effector IPI-O via the cell attachment motif RGD. T-DNA mutants deficient in LecRK-I.9 and transgenic Arabidopsis lines expressing ipiO1 were found to behave as phenocopies. Both show a ‘gain-of-susceptibility’ phenotype towards the Arabidopsis pathogen Phytophthora brassicae and are disturbed in callose deposition. Overall, the results suggest that destabilizing the CW-PM continuum is a strategy for Phytophthora to promote infection. As countermeasure, the host may want to strengthen CW-PM adhesions, and the novel resistance component LecRK-I.9 apparently functions in this process.
Collapse
Affiliation(s)
- Klaas Bouwmeester
- Laboratory of Phytopathology, Plant Sciences Group, Wageningen University, Wageningen, The Netherlands
- Centre for BioSystems Genomics (CBSG), Wageningen, The Netherlands
| | - Mara de Sain
- Laboratory of Phytopathology, Plant Sciences Group, Wageningen University, Wageningen, The Netherlands
- Centre for BioSystems Genomics (CBSG), Wageningen, The Netherlands
| | - Rob Weide
- Laboratory of Phytopathology, Plant Sciences Group, Wageningen University, Wageningen, The Netherlands
| | - Anne Gouget
- UMR 5546 CNRS-Université Paul Sabatier-Toulouse III, Castanet-Tolosan, France
| | - Sofieke Klamer
- Laboratory of Phytopathology, Plant Sciences Group, Wageningen University, Wageningen, The Netherlands
| | - Herve Canut
- UMR 5546 CNRS-Université Paul Sabatier-Toulouse III, Castanet-Tolosan, France
| | - Francine Govers
- Laboratory of Phytopathology, Plant Sciences Group, Wageningen University, Wageningen, The Netherlands
- Centre for BioSystems Genomics (CBSG), Wageningen, The Netherlands
- * E-mail:
| |
Collapse
|
15
|
Rask TS, Hansen DA, Theander TG, Gorm Pedersen A, Lavstsen T. Plasmodium falciparum erythrocyte membrane protein 1 diversity in seven genomes--divide and conquer. PLoS Comput Biol 2010; 6. [PMID: 20862303 PMCID: PMC2940729 DOI: 10.1371/journal.pcbi.1000933] [Citation(s) in RCA: 255] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2010] [Accepted: 08/16/2010] [Indexed: 12/21/2022] Open
Abstract
The var gene encoded hyper-variable Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) family mediates cytoadhesion of infected erythrocytes to human endothelium. Antibodies blocking cytoadhesion are important mediators of malaria immunity acquired by endemic populations. The development of a PfEMP1 based vaccine mimicking natural acquired immunity depends on a thorough understanding of the evolved PfEMP1 diversity, balancing antigenic variation against conserved receptor binding affinities. This study redefines and reclassifies the domains of PfEMP1 from seven genomes. Analysis of domains in 399 different PfEMP1 sequences allowed identification of several novel domain classes, and a high degree of PfEMP1 domain compositional order, including conserved domain cassettes not always associated with the established group A–E division of PfEMP1. A novel iterative homology block (HB) detection method was applied, allowing identification of 628 conserved minimal PfEMP1 building blocks, describing on average 83% of a PfEMP1 sequence. Using the HBs, similarities between domain classes were determined, and Duffy binding-like (DBL) domain subclasses were found in many cases to be hybrids of major domain classes. Related to this, a recombination hotspot was uncovered between DBL subdomains S2 and S3. The VarDom server is introduced, from which information on domain classes and homology blocks can be retrieved, and new sequences can be classified. Several conserved sequence elements were found, including: (1) residues conserved in all DBL domains predicted to interact and hold together the three DBL subdomains, (2) potential integrin binding sites in DBLα domains, (3) an acylation motif conserved in group A var genes suggesting N-terminal N-myristoylation, (4) PfEMP1 inter-domain regions proposed to be elastic disordered structures, and (5) several conserved predicted phosphorylation sites. Ideally, this comprehensive categorization of PfEMP1 will provide a platform for future studies on var/PfEMP1 expression and function. About one million African children die from malaria every year. The severity of malaria infections in part depends on which type of the parasitic protein PfEMP1 is expressed on the surface of the infected red blood cells. Natural immunity to malaria is mediated through antibodies to PfEMP1. Therefore hopes for a malaria vaccine based on PfEMP1 proteins have been raised. However, the large sequence variation among PfEMP1 molecules has caused great difficulties in executing and interpreting studies on PfEMP1. Here, we present an extensive sequence analysis of all currently available PfEMP1 sequences and show that PfEMP1 variation is ordered and can be categorized at different levels. In this way, PfEMP1 belong to group A–E and are composed of up to four components, each component containing specific DBL or CIDR domain subclasses, which in some cases form entire conserved domain combinations. Finally, each PfEMP1 can be described in high detail as a combination of 628 homology blocks. This dissection of PfEMP1 diversity also enables predictions of several functional sequence motifs relevant to the fold of PfEMP1 proteins and their ability to bind human receptors. We therefore believe that this description of PfEMP1 diversity is necessary and helpful for the design and interpretation of future PfEMP1 studies.
Collapse
Affiliation(s)
- Thomas S. Rask
- Center for Biological Sequence Analysis, Department of Systems Biology, Technical University of Denmark, Lyngby, Denmark
- Centre for Medical Parasitology, Department of Medical Microbiology and Immunology, University of Copenhagen, Copehagen, Denmark
- * E-mail: (TSR); (TL)
| | - Daniel A. Hansen
- Center for Biological Sequence Analysis, Department of Systems Biology, Technical University of Denmark, Lyngby, Denmark
| | - Thor G. Theander
- Centre for Medical Parasitology, Department of Medical Microbiology and Immunology, University of Copenhagen, Copehagen, Denmark
| | - Anders Gorm Pedersen
- Center for Biological Sequence Analysis, Department of Systems Biology, Technical University of Denmark, Lyngby, Denmark
| | - Thomas Lavstsen
- Centre for Medical Parasitology, Department of Medical Microbiology and Immunology, University of Copenhagen, Copehagen, Denmark
- * E-mail: (TSR); (TL)
| |
Collapse
|
16
|
Volgger M, Lang I, Ovecka M, Lichtscheidl I. Plasmolysis and cell wall deposition in wheat root hairs under osmotic stress. PROTOPLASMA 2010; 243:51-62. [PMID: 19533299 DOI: 10.1007/s00709-009-0055-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2009] [Accepted: 05/25/2009] [Indexed: 05/27/2023]
Abstract
We analysed cell wall formation in rapidly growing root hairs of Triticum aestivum under reduced turgor pressure by application of iso- and hypertonic mannitol solutions. Our experimental series revealed an osmotic value of wheat root hairs of 150 mOsm. In higher concentrations (200-650 mOsm), exocytosis of wall material and its deposition, as well as callose synthesis, still occurred, but the elongation of root hairs was stopped. Even after strong plasmolysis when the protoplast retreated from the cell wall, deposits of wall components were observed. Labelling with DiOC(6)(3) and FM1-43 revealed numerous Hechtian strands that spanned the plasmolytic space. Interestingly, the Hechtian strands also led towards the very tip of the root hair suggesting strong anchoring sites that are readily incorporated into the new cell wall. Long-term treatments of over 24 h in mannitol solutions (150-450 mOsm) resulted in reduced growth and concentration-dependent shortening of root hairs. However, the formation of new root hairs does occur in all concentrations used. This reflects the extraordinary potential of wheat root cells to adapt to environmental stress situations.
Collapse
Affiliation(s)
- Michael Volgger
- Cell Imaging and Ultrastructure Research, Faculty of Life Sciences, The University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
| | | | | | | |
Collapse
|
17
|
da Silva Castro N, Barbosa MS, Maia ZA, Báo SN, Felipe MSS, Santana JM, Soares Mendes-Giannini MJ, Pereira M, de Almeida Soares CM. Characterization ofParacoccidioides brasiliensis PbDfg5p, a cell-wall protein implicated in filamentous growth. Yeast 2008; 25:141-54. [DOI: 10.1002/yea.1574] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
|
18
|
Nakahata AM, Bueno NR, Rocha HAO, Franco CRC, Chammas R, Nakaie CR, Jasiulionis MG, Nader HB, Santana LA, Sampaio MU, Oliva MLV. Structural and inhibitory properties of a plant proteinase inhibitor containing the RGD motif. Int J Biol Macromol 2006; 40:22-9. [PMID: 16846639 DOI: 10.1016/j.ijbiomac.2006.05.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2006] [Revised: 05/12/2006] [Accepted: 05/12/2006] [Indexed: 11/26/2022]
Abstract
Purified from Bauhinia rufa seeds, BrTI is a Kunitz proteinase inhibitor that contains the RGD sequence. BrTI inhibits trypsin (K(iapp) 2.9 nM) and human plasma kallikrein (K(iapp) 14.0 nM) but not other related enzymes. The synthetic peptide YLEPVARGDGGLA-NH(2) (70 microM) inhibited the adhesion to fibronectin of B16F10 (high-metastatic B16 murine mouse melanoma cell line) and of Tm5 (murine melanoma cell lines derived from a non-tumorigenic lineage of pigmented murine melanocytes, melan-a). YLEPVARGEGGLA-NH(2) in which Asp(9) was changed into Glu does not affect the cell attachment. Moreover, this peptide was functional only when the sequence present in the native protein was preserved, since YLIPVARGDGGLA-NH(2) in which Glu(3) was changed into Ile does not interfere with B16F10 and was less effective on Tm5 cell line adhesion. Neither YLEPVARGDGGLA-NH(2), YLIPVARGDGGLA-NH(2) or YLEPVARGEGGLA-NH(2) inhibit the interaction of RAEC (endothelial cell line from rabbit aorta) with fibronectin.
Collapse
Affiliation(s)
- Adriana M Nakahata
- Department of Biochemistry, Universidade Federal de São Paulo-Escola Paulista de Medicina, Rua Três de Maio 100, 04044-020 São Paulo, SP, Brazil
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Pereyra E, Ingerfeld M, Anderson N, Jackson SL, Moreno S. Mucor rouxii ultrastructure: cyclic AMP and actin cytoskeleton. PROTOPLASMA 2006; 228:189-99. [PMID: 16983486 DOI: 10.1007/s00709-006-0184-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2005] [Accepted: 11/08/2005] [Indexed: 05/11/2023]
Abstract
A comparative analysis of the effect of two compounds, dibutyryl-cyclic-AMP (dbcAMP) and latrunculin B, on the morphology and ultrastructure of the dimorphic fungus Mucor rouxii under aerobic growth conditions is presented. dbcAMP acts through the sustained activation of protein kinase A, and latrunculin B through the disruption of the actin cytoskeleton. Upon addition of these compounds to the growth medium at any stage of the germination process, cells lost polarised growth and switched to isodiametric growth. The effect was reversible. The morphologies, visualised by light microscopy or scanning electron microscopy (SEM), were alike. A switch from a rough to a smooth surface was observed by SEM when cells were repolarised by removal of the added compound. Ultrastructural changes under both conditions, as observed by transmission electron microscopy, were similar, the main feature being the enlargement of the cell wall, with irregular depositions, and detachment from the cell membrane. dbcAMP-treated cells showed a decrease in the number of glycogen granules compared with control and latrunculin B-treated cells. F-actin staining with fluorescein isothiocyanate-phalloidin showed that both dbcAMP- and latrunculin B-treated cells displayed a much lower fluorescence than control cells, with only a few pale plaques. The results suggest that the sustained activation of protein kinase A, which impairs polarised growth, might exert its effect through a modification of actin cytoskeleton organisation, very probably also involving an integrinlike pathway, as judged by the cell wall detachment and loss of cell adhesiveness of the dbcAMP-treated isodiametric cells.
Collapse
Affiliation(s)
- E Pereyra
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.
| | | | | | | | | |
Collapse
|
20
|
Zhang Z, Henderson C, Perfect E, Carver TLW, Thomas BJ, Skamnioti P, Gurr SJ. Of genes and genomes, needles and haystacks: Blumeria graminis and functionality. MOLECULAR PLANT PATHOLOGY 2005; 6:561-75. [PMID: 20565680 DOI: 10.1111/j.1364-3703.2005.00303.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
SUMMARY Here, we consider the barley powdery mildew fungus, Blumeria graminis (DC Speer) f.sp. hordei (Marchal), and review recent research which has added to our understanding of the biology and molecular biology which underpins the asexual life cycle of this potentially devastating pathogen. We focus on the early stages of the host-pathogen interaction and report current understanding in the areas of leaf perception, fungal signal transduction and host-imposed oxidative stress management. Through this, it is becoming increasingly clear how closely and subtly both sides of the relationship are regulated. Collectively, however, this review highlights the high degree of complexity in working with an obligate parasite. Our experiences suggest that we would make more efficient progress towards understanding the basis of susceptibility and resistance to this true obligate biotroph if its genome sequence was available.
Collapse
Affiliation(s)
- Z Zhang
- Plant Sciences Department, South Parks Road, University of Oxford, Oxford OX1 3RB, UK
| | | | | | | | | | | | | |
Collapse
|
21
|
Abstract
Candida species are considered as the most important fungal human pathogens, causing a variety of clinical entities, ranging from superficial, cutaneous-mucosal to deep-seated and disseminated infections. A vast body of scientific literature, has been accumulated on these pathogens. A review of the literature and topics for further research are discussed.
Collapse
Affiliation(s)
- Esther Segal
- Department of Human Microbiology, Sackler School of Medicine, Tel-Aviv University, Tel-Aviv 69978, Israel.
| |
Collapse
|
22
|
Miozzi L, Balestrini R, Bolchi A, Novero M, Ottonello S, Bonfante P. Phospholipase A2 up-regulation during mycorrhiza formation in Tuber borchii. THE NEW PHYTOLOGIST 2005; 167:229-38. [PMID: 15948845 DOI: 10.1111/j.1469-8137.2005.01400.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
TbSP1 is a secreted and surface-associated phospholipase A(2) previously found to be up-regulated in C- or N-deprived free-living mycelia from the ectomycorrhizal ascomycete Tuber borchii. As nutrient limitation is considered an important environmental factor favouring the transition to symbiotic status, TbSP1 was suggested to be involved in the formation of mycorrhizas. An in vitro symbiosis system between Cistus incanus and T. borchii was set up: TbSP1 mRNA levels in free-living mycelia and in mycorrhizas sampled in different districts of the plant-fungus interaction were examined. In the same samples, TbSP1 protein expression was analysed by immunoelectron microscopy. A substantially enhanced TbSP1 mRNA expression, compared with nutrient-limited but free-living mycelia, was detected in the presence of the plant and reached maximal levels in fully developed mycorrhizas. A similar expression trend was revealed by immunolocalization experiments. We have shown that TbSP1 appears to respond to two partially overlapping yet distinct stimuli: nutrient starvation and mycorrhiza formation.
Collapse
Affiliation(s)
- Laura Miozzi
- Dipartimento di Biologia Vegetale, Università di Torino, Torino, Italy
| | | | | | | | | | | |
Collapse
|
23
|
Zhao H, Wang BC, Zhao HC, Wang JB. Stress stimulus induced resistance to Cladosporium cucumerinum in cucumber seeding. Colloids Surf B Biointerfaces 2005; 44:36-40. [PMID: 16002268 DOI: 10.1016/j.colsurfb.2005.04.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2004] [Accepted: 04/25/2005] [Indexed: 10/25/2022]
Abstract
Up to date, the studies of plant induced resistance have become the focus in plant pathology and physiology. During the course of pathogens penetrating the plant cell, besides of chemical secretion, the pathogens may generate mechanical signal caused by the physical pressure on the plant cell. In the non-host resistance, both the chemical signal and the mechanical stress signal are considered to have contribution to the entire defense reaction acted by the plant. The penetration of pathogen Cladosporium cucumerinum to cucumber is thought to be one of the model in research of plant induced resistance. In the current study, as a mechanical signal elicitor, the appropriate stress stimulus was proved to effectually induce the resistance of cucumber seedling to C. cucumerinum. After the treatment of the stress stimulus on leaves, the activities of resistance-related enzymes were significantly increased, such as phenylanine ammonia lyase (PAL), peroxidase (POD). Also, we found that stress stimulation may cause synthesis of lignin, which acts as the physical barrier to defense the pathogens. The results suggest that stress stimulation may not only enhance ability of the plant cell resistance to pathogen penetration but also elicit the accumulation of pathogens suppression or antimicrobial chemical substance in the plant cell.
Collapse
Affiliation(s)
- Huan Zhao
- Key Lab of Biomechanics and Tissue Engineering, The State ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044, PR China
| | | | | | | |
Collapse
|
24
|
Zhao HC, Zhao H, Wang BC, Wang JB. Effect of local stress induction on resistance-related enzymes in cucumber seeding. Colloids Surf B Biointerfaces 2005; 43:37-42. [PMID: 15913967 DOI: 10.1016/j.colsurfb.2005.01.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2004] [Accepted: 01/14/2005] [Indexed: 11/28/2022]
Abstract
In the current study, we found that the stress stimulus can act as a kind of elicitor, which can efficiently induce the resistance of cucumber against fungal pathogen. After the treatment of the stress stimulus on leaves, the activities of resistance-related enzymes were increased significantly. Such as phenylamine ammonia lyase (PAL), peroxidase (POD) and polyphenoloxidase (PPO), which are strongly associated with the plant disease resistance. Also the expression of pathogenesis-related protein (PR protein) were activated by stress stimulus, with the results that the activities of chitinase and beta-l,3-glucanase were increased obviously. The data showed that one of the mechanism of stress stimulus induction plant resistance may act via eliciting the metabolism related disease resistance within plant, which can produce many suppressing and antimicrobial compounds to against pathogens infection efficiently.
Collapse
Affiliation(s)
- Hu-cheng Zhao
- Biomechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing, China.
| | | | | | | |
Collapse
|
25
|
Robold AV, Hardham AR. During attachment Phytophthora spores secrete proteins containing thrombospondin type 1 repeats. Curr Genet 2005; 47:307-15. [PMID: 15815927 DOI: 10.1007/s00294-004-0559-8] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2004] [Revised: 12/05/2004] [Accepted: 12/13/2004] [Indexed: 10/25/2022]
Abstract
Adhesion is a key aspect of disease establishment in animals and plants. Adhesion anchors the parasite to the host surface and is a prerequisite for further development and host cell invasion. Although a number of adhesin molecules produced by animal pathogens have been characterised, molecular details of adhesins of plant pathogens, especially fungi, are largely restricted to general descriptions of the nature of heterogeneous secreted materials. In this paper, we report the cloning of a gene, PcVsv1, encoding a protein secreted during attachment of spores of Phytophthora, a genus of highly destructive plant pathogens. PcVsv1 contains 47 copies of the thrombospondin type 1 repeat, a motif found in adhesins of animals and malarial parasites but not in plants, green algae or true fungi. Our results suggest that PcVsv1 is a spore adhesin and highlight intriguing similarities in structural and molecular features of host attachment in oomycete and malarial parasites.
Collapse
Affiliation(s)
- Andrea V Robold
- Plant Cell Biology Group, Research School of Biological Sciences, The Australian National University, Canberra, ACT 2601, Australia
| | | |
Collapse
|
26
|
Bakkeren G, Gold S. The path in fungal plant pathogenicity: many opportunities to outwit the intruders? GENETIC ENGINEERING 2004; 26:175-223. [PMID: 15387298 DOI: 10.1007/978-0-306-48573-2_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
The number of genes implicated in the infection and disease processes of phytopathogenic fungi is increasing rapidly. Forward genetic approaches have identified mutated genes that affect pathogenicity, host range, virulence and general fitness. Likewise, candidate gene approaches have been used to identify genes of interest based on homology and recently through 'comparative genomic approaches' through analysis of large EST databases and whole genome sequences. It is becoming clear that many genes of the fungal genome will be involved in the pathogen-host interaction in its broadest sense, affecting pathogenicity and the disease process in planta. By utilizing the information obtained through these studies, plants may be bred or engineered for effective disease resistance. That is, by trying to disable pathogens by hitting them where it counts.
Collapse
Affiliation(s)
- Guus Bakkeren
- Agriculture & Agri-Food Canada,Pacific Agri-Food Research Centre, Summerland, BC, Canada V0H 1Z0
| | | |
Collapse
|
27
|
Facchiano AM, Facchiano A, Facchiano F. Active Sequences Collection (ASC) database: a new tool to assign functions to protein sequences. Nucleic Acids Res 2003; 31:379-82. [PMID: 12520027 PMCID: PMC165489 DOI: 10.1093/nar/gkg042] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Active Sequences Collection (ASC) is a collection of amino acid sequences, with an unique feature: only short sequences are collected, with a demonstrated biological activity. The current version of ASC consists of three sections: DORRS, a collection of active RGD-containing peptides; TRANSIT, a collection of protein regions active as substrates of transglutaminase enzyme (TGase), and BAC, a collection of short peptides with demonstrated biological activity. Literature references for each entry are reported, as well as cross references to other databases, when available. The current version of ASC includes more than 800 different entries. The main scope of this collection is to offer a new tool to investigate the structural features of protein active sites, additionally to similarity searches against large protein databases or searching for known functional patterns. ASC database is available at the web address http://crisceb.unina2.it/ASC/ which also offers a dedicated query interface to compare user-defined protein sequences with the database, as well as an updating interface to allow contribution of new referenced active sequences.
Collapse
Affiliation(s)
- Angelo M Facchiano
- Istituto di Scienze dell'Alimentazione, CNR-via Roma 52A/C 83100 Avellino, Italy.
| | | | | |
Collapse
|
28
|
Peng CYS, Zhou X, Kaya HK. Virulence and site of infection of the fungus, Hirsutella thompsonii, to the honey bee ectoparasitic mite, Varroa destructor. J Invertebr Pathol 2002; 81:185-95. [PMID: 12507488 DOI: 10.1016/s0022-2011(02)00188-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The Varroa mite, Varroa destructor, is recognized as the most serious pest of both managed and feral Western honey bee (Apis mellifera) in the world. The mite has developed resistance to fluvalinate, an acaricide used to control it in beehives, and fluvalinate residues have been found in the beeswax, necessitating an urgent need to find alternative control measures to suppress this pest. Accordingly, we investigated the possibility of using the fungus, Hirsutella thompsonii, as a biocontrol agent of the Varroa mite. Among the 9 isolates of H. thompsonii obtained from the University of Florida and the USDA, only the 3 USDA isolates (ARSEF 257, 1947 and 3323) were infectious to the Varroa mite in laboratory tests. The mite became infected when it was allowed to walk on a sporulating H. thompsonii culture for 5 min. Scanning electron micrographs revealed that the membranous arolium of the mite leg sucker is the focus of infection where the fungal conidia adhered and germinated. The infected mites died from mycosis, with the lethal times to kill 50% (LT(50)s) dependent on the fungal isolates. Thus, the LT(50)s were 52.7, 77.2, and 96.7h for isolates 3323, 257, and 1947, respectively. Passage of H. thompsonii through Varroa mite three times significantly reduced the LT(50)s of isolates 257 and 1947 (P<0.05) but not the LT(50) of isolate 3323. The fungus did not infect the honey bee in larval, prepupal, pupal, and adult stages under our laboratory rearing conditions. Our encouraging results suggest that some isolates of H. thompsonii have the potential to be developed as a biocontrol agent for V. destructor. However, fungal infectivity against the mites under beehive conditions needs to be studied before any conclusion can be made.
Collapse
Affiliation(s)
- Christine Y S Peng
- Department of Entomology, University of California, One Shields Avenue, Davis, CA 95616, USA
| | | | | |
Collapse
|
29
|
Rodriguez-Galán MC, Correa SG, Iribarren P, Sotomayor CE. Phenotypic and functional changes on phagocytic cells recruited at the site of Candida albicans infection after chronic varied stress exposure. Med Mycol 2002; 40:485-92. [PMID: 12462528 DOI: 10.1080/mmy.40.5.485.492] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
The transition of Candida albicans from commensalism to pathogenicity is associated with the immune status of the host; resistance to fungus involves macrophages (Mphi) and polymorphonuclear neutrophils (PMN), which act as effector cells. T-cell function is also involved. Previously, we found that in Wistar rats exposed to chronic varied stress (CVS) immediately after C. albicans infection (Ca-S group) some functions of phagocytic cells, such as killer activity and NO production, were strongly modified compared with unstressed, infected animals (Ca group). We examined the phenotypic and functional changes of these effector cells recruited at the site of C. albicans infection. The recruitment of peritoneal cells (PC) was markedly reduced in Ca-S animals and the arrival of Mphi and PMN was selectively diminished after CVS exposure. The integrin CD11b/CD18, implicated in migration and C. albicans phagocytosis, was downregulated in Mphi of Ca-S animals. The activation markers CD54 and MHC-II were upregulated in Mphi after fungal contact. The expression of CD54 was only changed in Ca-S rats. Finally, TNF-alpha production was reduced in PC of Ca-S animals, suggesting an impairment of functional activity. Taken together, the phenotypic and functional changes detected in effector cells may account for the decreased resistance to candidiasis seen in conjunction with CVS. The changes seen also expand our knowledge of the role of Mphi in the control of C. albicans dissemination.
Collapse
Affiliation(s)
- M C Rodriguez-Galán
- Inmunología, Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | | | | | | |
Collapse
|
30
|
Santoni G, Lucciarini R, Amantini C, Jacobelli J, Spreghini E, Ballarini P, Piccoli M, Gismondi A. Candida albicans expresses a focal adhesion kinase-like protein that undergoes increased tyrosine phosphorylation upon yeast cell adhesion to vitronectin and the EA.hy 926 human endothelial cell line. Infect Immun 2002; 70:3804-15. [PMID: 12065524 PMCID: PMC128043 DOI: 10.1128/iai.70.7.3804-3815.2002] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The signaling pathways triggered by adherence of Candida albicans to the host cells or extracellular matrix are poorly understood. We provide here evidence in C. albicans yeasts of a p105 focal adhesion kinase (Fak)-like protein (that we termed CaFak), antigenically related to the vertebrate p125Fak, and its involvement in integrin-like-mediated fungus adhesion to vitronectin (VN) and EA.hy 926 human endothelial cell line. Biochemical analysis with different anti-chicken Fak antibodies identified CaFak as a 105-kDa protein and immunofluorescence and cytofluorimetric analysis on permeabilized cells specifically stain C. albicans yeasts; moreover, confocal microscopy evidences CaFak as a cytosolic protein that colocalizes on the membrane with the integrin-like VN receptors upon yeast adhesion to VN. The protein tyrosine kinase (PTK) inhibitors genistein and herbimycin A strongly inhibited C. albicans yeast adhesion to VN and EA.hy 926 endothelial cells. Moreover, engagement of alpha v beta 3 and alpha v beta 5 integrin-like on C. albicans either by specific monoclonal antibodies or upon adhesion to VN or EA.hy 926 endothelial cells stimulates CaFak tyrosine phosphorylation that is blocked by PTK inhibitor. A role for CaFak in C. albicans yeast adhesion was also supported by the failure of VN to stimulate its tyrosine phosphorylation in a C. albicans mutant showing normal levels of CaFak and VNR-like integrins but displaying reduced adhesiveness to VN and EA.hy 926 endothelial cells. Our results suggest that C. albicans Fak-like protein is involved in the control of yeast cell adhesion to VN and endothelial cells.
Collapse
Affiliation(s)
- Giorgio Santoni
- Department of Pharmacological Sciences and Experimental Medicine, University of Camerino, 62032 Camerino, Italy.
| | | | | | | | | | | | | | | |
Collapse
|
31
|
Abstract
Candida species other than Candida albicans now account for up to 50% of deep candidiasis cases, yet little attention has been paid to the virulence attributes of these fungi. Adherence to host tissues, response to environmental changes and the secretion of hydrolases are all thought to be important in Candida virulence. The identification of virulence attributes unique to a particular Candida species could provide powerful insights into the pathogenic process but will require the use of genome-wide approaches such as transcript profiling, signature-tagged mutagenesis and in vivo expression technology.
Collapse
Affiliation(s)
- K Haynes
- Dept of Infectious Diseases, Faculty of Medicine, Imperial College of Science, Technology & Medicine, Du Cane Road, W12 0NN, London, UK.
| |
Collapse
|
32
|
Lima OC, Figueiredo CC, Previato JO, Mendonça-Previato L, Morandi V, Lopes Bezerra LM. Involvement of fungal cell wall components in adhesion of Sporothrix schenckii to human fibronectin. Infect Immun 2001; 69:6874-80. [PMID: 11598061 PMCID: PMC100066 DOI: 10.1128/iai.69.11.6874-6880.2001] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Systemic sporotrichosis is an emerging infection potentially fatal for immunocompromised patients. Adhesion to extracellular matrix proteins is thought to play a crucial role in invasive fungal diseases. Here we report studies of the adhesion of Sporothrix schenckii to the extracellular protein fibronectin (Fn). Both yeast cells and conidia of S. schenckii were able to adhere to Fn as detected by enzyme-linked immunosorbent binding assays. Adhesion of yeast cells to Fn is dose dependent and saturable. S. schenckii adheres equally well to 40-kDa and 120-kDa Fn proteolytic fragments. While adhesion to Fn was increased by Ca(2+), inhibition assays demonstrated that it was not RGD dependent. A carbohydrate-containing cell wall neutral fraction blocked up to 30% of the observed adherence for the yeast cells. The biochemical nature of this fraction suggests the participation of cell surface glycoconjugates in binding by their carbohydrate or peptide moieties. These results provide new data concerning S. schenckii adhesion mechanisms, which could be important in host-fungus interactions and the establishment of sporotrichosis.
Collapse
Affiliation(s)
- O C Lima
- Departamento de Biologia Celular e Genética, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | | | | | | | | | | |
Collapse
|
33
|
Jones H, Whipps JM, Gurr SJ. The tomato powdery mildew fungus Oidium neolycopersici. MOLECULAR PLANT PATHOLOGY 2001; 2:303-9. [PMID: 20573019 DOI: 10.1046/j.1464-6722.2001.00084.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
UNLABELLED summary Pathogen: Powdery mildew fungus; Ascomycete although sexual stage is yet to be found; an obligate biotroph. IDENTIFICATION Superficial mycelium with hyaline hyphae; unbranched erect conidiophores; conidia, ellipsoid-ovoid or doliform, 22-46 x 10-20 microm, lack fibrosin bodies; conidia formed singly, rarely in short chains of 2-6 conidia; appressoria lobed to multilobed, rarely nipple-shaped. Pseudoidium species. HOST RANGE Broad, reported to attack over 60 species in 13 plant families, particularly members of the Solanaceae and Curcubitaceae. SYMPTOMS Powdery white lesions on all aerial plant parts except the fruit. In severe outbreaks the lesions coalesce and disease is debilitating. Agronomic importance: Extremely common in glasshouse tomatoes world wide but increasing in importance on field grown tomato crops. CONTROL Chemical control and breeding programmes for disease resistance.
Collapse
Affiliation(s)
- H Jones
- Department of Plant Sciences, South Parks Road, University of Oxford, Oxford, OX1 3RB, UK
| | | | | |
Collapse
|
34
|
Soragni E, Bolchi A, Balestrini R, Gambaretto C, Percudani R, Bonfante P, Ottonello S. A nutrient-regulated, dual localization phospholipase A(2) in the symbiotic fungus Tuber borchii. EMBO J 2001; 20:5079-90. [PMID: 11566873 PMCID: PMC125632 DOI: 10.1093/emboj/20.18.5079] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Important morphogenetic transitions in fungi are triggered by starvation-induced changes in the expression of structural surface proteins. Here, we report that nutrient deprivation causes a strong and reversible up-regulation of TbSP1, a surface-associated, Ca(2+)-dependent phospholipase from the mycorrhizal fungus Tuber borchii. TbSP1 is the first phospholipase A(2) to be described in fungi and identifies a novel class of phospholipid-hydrolyzing enzymes. The TbSP1 phospholipase, which is synthesized initially as a pre-protein, is processed efficiently and secreted during the mycelial phase. The mature protein, however, also localizes to the inner cell wall layer, close to the plasma membrane, in both free-living and symbiosis-engaged hyphae. It thus appears that a dual localization phospholipase A(2) is involved in the adaptation of a symbiotic fungus to conditions of persistent nutritional limitation. Moreover, the fact that TbSP1-related sequences are present in Streptomyces and Neurospora, and not in wholly sequenced non-filamentous microorganisms, points to a general role for TbSP1 phospholipases A(2) in the organization of multicellular filamentous structures in bacteria and fungi.
Collapse
Affiliation(s)
- Elisabetta Soragni
- Dipartimento di Biochimica e Biologia Molecolare, Università di Parma, Parco Area delle Scienze 23/A, I-43100 Parma and
Centro di Studio sulla Micologia del Terreno (CNR) and Dipartimento di Biologia Vegetale, Università di Torino, Vialle Mattioli 25, I-10125 Torino, Italy Present address: Center for Molecular Genetics, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0634, USA Corresponding author e-mail:
| | | | - Raffaella Balestrini
- Dipartimento di Biochimica e Biologia Molecolare, Università di Parma, Parco Area delle Scienze 23/A, I-43100 Parma and
Centro di Studio sulla Micologia del Terreno (CNR) and Dipartimento di Biologia Vegetale, Università di Torino, Vialle Mattioli 25, I-10125 Torino, Italy Present address: Center for Molecular Genetics, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0634, USA Corresponding author e-mail:
| | | | | | - Paola Bonfante
- Dipartimento di Biochimica e Biologia Molecolare, Università di Parma, Parco Area delle Scienze 23/A, I-43100 Parma and
Centro di Studio sulla Micologia del Terreno (CNR) and Dipartimento di Biologia Vegetale, Università di Torino, Vialle Mattioli 25, I-10125 Torino, Italy Present address: Center for Molecular Genetics, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0634, USA Corresponding author e-mail:
| | - Simone Ottonello
- Dipartimento di Biochimica e Biologia Molecolare, Università di Parma, Parco Area delle Scienze 23/A, I-43100 Parma and
Centro di Studio sulla Micologia del Terreno (CNR) and Dipartimento di Biologia Vegetale, Università di Torino, Vialle Mattioli 25, I-10125 Torino, Italy Present address: Center for Molecular Genetics, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0634, USA Corresponding author e-mail:
| |
Collapse
|