1
|
de Oliveira Silva A, Fernando Devasahayam BR, Aliyeva-Schnorr L, Glienke C, Deising HB. The serine-threonine protein kinase Snf1 orchestrates the expression of plant cell wall-degrading enzymes and is required for full virulence of the maize pathogen Colletotrichum graminicola. Fungal Genet Biol 2024; 171:103876. [PMID: 38367799 DOI: 10.1016/j.fgb.2024.103876] [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: 12/05/2023] [Revised: 02/12/2024] [Accepted: 02/14/2024] [Indexed: 02/19/2024]
Abstract
Colletotrichum graminicola, the causal agent of maize leaf anthracnose and stalk rot, differentiates a pressurized infection cell called an appressorium in order to invade the epidermal cell, and subsequently forms biotrophic and necrotrophic hyphae to colonize the host tissue. While the role of force in appressorial penetration is established (Bechinger et al., 1999), the involvement of cell wall-degrading enzymes (CWDEs) in this process and in tissue colonization is poorly understood, due to the enormous number and functional redundancy of these enzymes. The serine/threonine protein kinase gene SNF1 identified in Sucrose Non-Fermenting yeast mutants mediates de-repression of catabolite-repressed genes, including many genes encoding CWDEs. In this study, we identified and functionally characterized the SNF1 homolog of C. graminicola. Δsnf1 mutants showed reduced vegetative growth and asexual sporulation rates on media containing polymeric carbon sources. Microscopy revealed reduced efficacies in appressorial penetration of cuticle and epidermal cell wall, and formation of unusual medusa-like biotrophic hyphae by Δsnf1 mutants. Severe and moderate virulence reductions were observed on intact and wounded leaves, respectively. Employing RNA-sequencing we show for the first time that more than 2,500 genes are directly or indirectly controlled by Snf1 in necrotrophic hyphae of a plant pathogenic fungus, many of which encode xylan- and cellulose-degrading enzymes. The data presented show that Snf1 is a global regulator of gene expression and is required for full virulence.
Collapse
Affiliation(s)
- Alan de Oliveira Silva
- Chair of Phytopathology and Plant Protection, Institute for Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, Germany; Department of Genetics, Federal University of Paraná, Curitiba, PR, Brazil
| | - Bennet Rohan Fernando Devasahayam
- Chair of Phytopathology and Plant Protection, Institute for Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, Germany; German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Germany
| | - Lala Aliyeva-Schnorr
- Chair of Phytopathology and Plant Protection, Institute for Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, Germany
| | - Chirlei Glienke
- Department of Genetics, Federal University of Paraná, Curitiba, PR, Brazil
| | - Holger B Deising
- Chair of Phytopathology and Plant Protection, Institute for Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, Germany; German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Germany.
| |
Collapse
|
2
|
Li F, Zhu R, Gao F, Duan T. Prior Infection by Colletotrichum spinaciae Lowers the Susceptibility to Infection by Powdery Mildew in Common Vetch. PLANTS (BASEL, SWITZERLAND) 2023; 13:52. [PMID: 38202360 PMCID: PMC10780821 DOI: 10.3390/plants13010052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 12/20/2023] [Accepted: 12/20/2023] [Indexed: 01/12/2024]
Abstract
Anthracnose (Colletotrichum spinaciae) and powdery mildew (Erysiphe pisi) are important diseases of common vetch (Vicia sativa) and often co-occur in the same plant. Here, we evaluate how C. spinaciae infection affects susceptibility to E. pisi, using sterilized and non-sterilized field soil to test the effect of resident soil microorganisms on the plant's immune response. Plants infected with C. spinaciae (C+) exhibited a respective 41.77~44.16% and 72.37~75.27% lower incidence and severity of powdery mildew than uninfected (C-) plants. Moreover, the net photosynthetic rate, transpiration rate, and stomatal conductance were higher in the C- plants than in the C+ plants prior to infection with powdery mildew. These differences were not recorded following powdery mildew infection. Additionally, the activities of superoxide dismutase, polyphenol oxidase, and catalase were higher in the C+ plants than in the C- plants. The resident soil microbiota did not affect the plant responses to both pathogens. By uncovering the mechanistic basis of plant immune response, our study informs integrated disease management in a globally important forage crop.
Collapse
Affiliation(s)
- Faxi Li
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, China; (F.L.); (R.Z.)
| | - Rui Zhu
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, China; (F.L.); (R.Z.)
| | - Feng Gao
- Gansu Vocational College of Agriculture, Lanzhou 730020, China
| | - Tingyu Duan
- State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, China; (F.L.); (R.Z.)
| |
Collapse
|
3
|
The roles of Salvia miltiorrhiza-derived carbon dots involving in maintaining quality by delaying senescence of postharvest flowering Chinese cabbage. Food Chem 2023; 404:134704. [DOI: 10.1016/j.foodchem.2022.134704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Revised: 09/22/2022] [Accepted: 10/18/2022] [Indexed: 11/06/2022]
|
4
|
Belisário R, Robertson AE, Vaillancourt LJ. Maize Anthracnose Stalk Rot in the Genomic Era. PLANT DISEASE 2022; 106:2281-2298. [PMID: 35291814 DOI: 10.1094/pdis-10-21-2147-fe] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Anthracnose stalk rot (ASR) of maize results in millions of dollars in losses annually in the United States. ASR, together with anthracnose leaf blight and anthracnose top dieback, is caused by the fungus Colletotrichum graminicola. Current ASR management recommendations emphasize host resistance and reduction of plant stressors (e.g., drought, heat, low fertility, or soil acidity). Stress reduction may be more difficult to achieve in the future due to more high-intensity production protocols and climate change. Moreover, cultural and chemical management practices may conflict with other important goals, including environmental sustainability and maximization of yield potential. Thus, future ASR management may rely more heavily on host resistance, for which there are relatively few highly effective sources. The last comprehensive review of C. graminicola and maize anthracnose was written over two decades ago. The genomic age has brought important new insights into mechanisms governing the host-pathogen interaction from the application of molecular and cytological technologies. This review provides a summary of our current model of maize anthracnose etiology, including how increased knowledge of molecular and cellular events could contribute to better ASR management. Improved understanding of C. graminicola taxonomy has confirmed that the fungus is specific to Zea mays, and that it colonizes living maize tissues via a critical biotrophic phase. Successful biotrophic establishment relies on an array of secreted protein effectors and secondary metabolites produced at different stages of infection and dispersed to multiple locations. These molecules could provide therapeutic targets for the next generation of transgenic or gene-edited ASR-resistant hybrids.
Collapse
Affiliation(s)
- Renata Belisário
- Department of Plant Pathology, University of Kentucky, 201F Plant Science Building, 1405 Veterans Drive, Lexington, KY 40546-0312
| | - Alison E Robertson
- Department of Plant Pathology and Microbiology, Iowa State University, 1344 Advanced Teaching and Research Building, 2213 Pammel Drive, Ames, IA 50011
| | - Lisa J Vaillancourt
- Department of Plant Pathology, University of Kentucky, 201F Plant Science Building, 1405 Veterans Drive, Lexington, KY 40546-0312
| |
Collapse
|
5
|
Hyphal Fusions Enable Efficient Nutrient Distribution in Colletotrichum graminicola Conidiation and Symptom Development on Maize. Microorganisms 2022; 10:microorganisms10061146. [PMID: 35744664 PMCID: PMC9231406 DOI: 10.3390/microorganisms10061146] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 05/25/2022] [Accepted: 05/30/2022] [Indexed: 02/01/2023] Open
Abstract
Hyphal and germling fusion is a common phenomenon in ascomycetous fungi. Due to the formed hyphal network, this process enables a coordinated development as well as an interaction with plant hosts and efficient nutrient distribution. Recently, our laboratory work demonstrated a positive correlation between germling fusion and the formation of penetrating hyphopodia on maize leaves outgoing from Colletotrichum graminicola oval conidia. To investigate the probable interconnectivity of these processes, we generated a deletion mutant in Cgso, in which homologs are essential for cellular fusion in other fungal species. However, hyphopodia development was not affected, indicating that both processes are not directly connected. Instead, we were able to link the cellular fusion defect in ∆Cgso to a decreased formation of asexual fruiting bodies of C. graminicola on the leaves. The monitoring of a fluorescent-labelled autophagy marker, eGFP-CgAtg8, revealed a high autophagy activity in the hyphae surrounding the acervuli. These results support the hypothesis that the efficient nutrient transport of degraded cellular material by hyphal fusions enables proper acervuli maturation and, therefore, symptom development on the leaves.
Collapse
|
6
|
Microbial interaction mediated programmed cell death in plants. 3 Biotech 2022; 12:43. [PMID: 35096500 PMCID: PMC8761208 DOI: 10.1007/s13205-021-03099-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 12/26/2021] [Indexed: 02/03/2023] Open
Abstract
Food demand of growing population can only be met by finding solutions for sustaining the crop yield. The understanding of basic mechanisms employed by microorganisms for the establishment of parasitic relationship with plants is a complex phenomenon. Symbionts and biotrophs are dependent on living hosts for completing their life cycle, whereas necrotrophs utilize dead cells for their growth and establishment. Hemibiotrophs as compared to other microbes associate themselves with plants in two phase's, viz. early bio-phase and later necro-phase. Plants and microbes interact with each other using receptors present on host cell surface and elicitors (PAMPs and effectors) produced by microbes. Plant-microbe interaction either leads to compatible or incompatible reaction. In response to various biotic and abiotic stress factors, plant undergoes programmed cell death which restricts the growth of biotrophs or hemibiotrophs while necrotrophs as an opportunist starts growing on dead tissue for their own benefit. PCD regulation is an outcome of plant-microbe crosstalk which entirely depends on various biochemical events like generation of reactive oxygen species, nitric oxide, ionic efflux/influx, CLPs, biosynthesis of phytohormones, phytoalexins, polyamines and certain pathogenesis-related proteins. This phenomenon mostly occurs in resistant and non-host plants during invasion of pathogenic microbes. The compatible or incompatible host-pathogen interaction depends upon the presence or absence of host plant resistance and pathogenic race. In addition to host-pathogen interaction, the defense induction by beneficial microbes must also be explored and used to the best of its potential. This review highlights the mechanism of microbe- or symbiont-mediated PCD along with defense induction in plants towards symbionts, biotrophs, necrotrophs and hemibiotrophs. Here we have also discussed the possible use of beneficial microbes in inducing systemic resistance in plants against pathogenic microbes.
Collapse
|
7
|
The Effect of Photoperiod on Necrosis Development, Photosynthetic Efficiency and 'Green Islands' Formation in Brassica juncea Infected with Alternaria brassicicola. Int J Mol Sci 2021; 22:ijms22168435. [PMID: 34445145 PMCID: PMC8395102 DOI: 10.3390/ijms22168435] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 07/30/2021] [Accepted: 08/02/2021] [Indexed: 01/06/2023] Open
Abstract
The main goal of growing plants under various photoperiods is to optimize photosynthesis for using the effect of day length that often acts on plants in combination with biotic and/or abiotic stresses. In this study, Brassica juncea plants were grown under four different day-length regimes, namely., 8 h day/16 h night, 12 h day/12 h night, 16 h day/8 h night, and continuous light, and were infected with a necrotrophic fungus Alternaria brassicicola. The development of necroses on B. juncea leaves was strongly influenced by leaf position and day length. The largest necroses were formed on plants grown under a 16 h day/8 h night photoperiod at 72 h post-inoculation (hpi). The implemented day-length regimes had a great impact on leaf morphology in response to A. brassicicola infection. They also influenced the chlorophyll and carotenoid contents and photosynthesis efficiency. Both the 1st (the oldest) and 3rd infected leaves showed significantly higher minimal fluorescence (F0) compared to the control leaves. Significantly lower values of other investigated chlorophyll a fluorescence parameters, e.g., maximum quantum yield of photosystem II (Fv/Fm) and non-photochemical quenching (NPQ), were observed in both infected leaves compared to the control, especially at 72 hpi. The oldest infected leaf, of approximately 30% of the B. juncea plants, grown under long-day and continuous light conditions showed a ‘green island’ phenotype in the form of a green ring surrounding an area of necrosis at 48 hpi. This phenomenon was also reflected in changes in the chloroplast’s ultrastructure and accelerated senescence (yellowing) in the form of expanding chlorosis. Further research should investigate the mechanism and physiological aspects of ‘green islands’ formation in this pathosystem.
Collapse
|
8
|
Eisermann I, Motyka V, Kümmel S, Dobrev PI, Hübner K, Deising HB, Wirsel SGR. CgIPT1 is required for synthesis of cis-zeatin cytokinins and contributes to stress tolerance and virulence in Colletotrichum graminicola. Fungal Genet Biol 2020; 143:103436. [PMID: 32693088 DOI: 10.1016/j.fgb.2020.103436] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 06/09/2020] [Accepted: 07/14/2020] [Indexed: 10/23/2022]
Abstract
We have previously shown that the maize pathogen Colletotrichum graminicola is able to synthesise cytokinins (CKs). However, it remained unsettled whether fungal CK production is essential for virulence in this hemibiotrophic fungus. Here, we identified a candidate gene, CgIPT1, that is homologous to MOD5 of Saccharomyces cerevisiae and genes from other fungi and plants, which encode tRNA-isopentenyltransferases (IPTs). We show that the wild type strain mainly synthesises cis-zeatin-type (cisZ) CKs whereas ΔCgipt1 mutants are severely impeded to do so. The spectrum of CKs produced confirms bioinformatical analyses predicting that CgIpt1 is a tRNA-IPT. The virulence of the ΔCgipt1 mutants is moderately reduced. Furthermore, the mutants exhibit increased sensitivities to osmotic stress imposed by sugar alcohols and salts, as well as cell wall stress imposed by Congo red. Amendment of media with CKs did not reverse this phenotype suggesting that fungal-derived CKs do not explain the role of CgIpt1 in mediating abiotic stress tolerance. Moreover, the mutants still cause green islands on senescing maize leaves indicating that the cisZ-type CKs produced by the fungus do not cause this phenotype.
Collapse
Affiliation(s)
- Iris Eisermann
- Institut für Agrar- und Ernährungswissenschaften, Naturwissenschaftliche Fakultät III, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 3, D-06120 Halle (Saale), Germany
| | - Václav Motyka
- Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, CZ-165 02 Prague 6, Czech Republic
| | - Stefanie Kümmel
- Institut für Agrar- und Ernährungswissenschaften, Naturwissenschaftliche Fakultät III, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 3, D-06120 Halle (Saale), Germany
| | - Petre I Dobrev
- Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, CZ-165 02 Prague 6, Czech Republic
| | - Konstantin Hübner
- Institut für Agrar- und Ernährungswissenschaften, Naturwissenschaftliche Fakultät III, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 3, D-06120 Halle (Saale), Germany
| | - Holger B Deising
- Institut für Agrar- und Ernährungswissenschaften, Naturwissenschaftliche Fakultät III, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 3, D-06120 Halle (Saale), Germany
| | - Stefan G R Wirsel
- Institut für Agrar- und Ernährungswissenschaften, Naturwissenschaftliche Fakultät III, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 3, D-06120 Halle (Saale), Germany.
| |
Collapse
|
9
|
Précigout PA, Claessen D, Makowski D, Robert C. Does the Latent Period of Leaf Fungal Pathogens Reflect Their Trophic Type? A Meta-Analysis of Biotrophs, Hemibiotrophs, and Necrotrophs. PHYTOPATHOLOGY 2020; 110:345-361. [PMID: 31577162 DOI: 10.1094/phyto-04-19-0144-r] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We performed a meta-analysis to search for a relation between the trophic type and latent period of fungal pathogens. The pathogen incubation period and the level of resistance of the hosts were also investigated. This ecological knowledge would help us to more efficiently regulate crop epidemics for different types of pathogens. We gathered latent period data from 103 studies dealing with 51 fungal pathogens of the three major trophic types (25 biotrophs, 15 hemibiotrophs, and 11 necrotrophs), representing 2,542 mean latent periods. We show that these three trophic types display significantly different latent periods. Necrotrophs exhibited the shortest latent periods (<100 degree-days [DD]), biotrophs had intermediate ones (between 100 and 200 DD), and hemibiotrophs had the longest latent periods (>200 DD). We argue that this relation between trophic type and latent period points to two opposing host exploitation strategies: necrotrophs mount a rapid destructive attack on the host tissue, whereas biotrophs and hemibiotrophs avoid or delay the damaging phase. We query the definition of hemibiotrophic pathogens and discuss whether the length of the latent period is determined by the physiological limits inherent to each trophic type or by the adaptation of pathogens of different trophic types to the contrasting conditions experienced in their interaction with the host.
Collapse
Affiliation(s)
- Pierre-Antoine Précigout
- Institut de Biologie de l'Ecole Normale Supérieure, CNRS-ENS-INSERM UMR8197, Ecole Normale Supérieure, 75005 Paris, France
- UMR EcoSys, Institut National de la Recherche Agronomique (INRA), AgroParisTech, 78850 Thiverval-Grignon, France
| | - David Claessen
- Institut de Biologie de l'Ecole Normale Supérieure, CNRS-ENS-INSERM UMR8197, Ecole Normale Supérieure, 75005 Paris, France
| | - David Makowski
- UMR Agronomie, INRA, AgroParisTech, Université Paris-Saclay, 78850 Thiverval-Grignon, France
| | - Corinne Robert
- UMR EcoSys, Institut National de la Recherche Agronomique (INRA), AgroParisTech, 78850 Thiverval-Grignon, France
| |
Collapse
|
10
|
Eisermann I, Weihmann F, Krijger JJ, Kröling C, Hause G, Menzel M, Pienkny S, Kiesow A, Deising HB, Wirsel SGR. Two genes in a pathogenicity gene cluster encoding secreted proteins are required for appressorial penetration and infection of the maize anthracnose fungus Colletotrichum graminicola. Environ Microbiol 2019; 21:4773-4791. [PMID: 31599055 DOI: 10.1111/1462-2920.14819] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 10/01/2019] [Accepted: 10/02/2019] [Indexed: 01/14/2023]
Abstract
To avoid pathogen-associated molecular pattern recognition, the hemibiotrophic maize pathogen Colletotrichum graminicola secretes proteins mediating the establishment of biotrophy. Targeted deletion of 26 individual candidate genes and seven gene clusters comprising 32 genes of C. graminicola identified a pathogenicity cluster (CLU5) of five co-linear genes, all of which, with the exception of CLU5b, encode secreted proteins. Targeted deletion of all genes of CLU5 revealed that CLU5a and CLU5d are required for full appressorial penetration competence, with virulence deficiencies independent of the host genotype and organ inoculated. Cytorrhysis experiments and microscopy showed that Δclu5a mutants form pressurized appressoria, but they are hampered in forming penetration pores and fail to differentiate a penetration peg. Whereas Δclu5d mutants elicited WT-like papillae, albeit at increased frequencies, papillae induced by Δclu5a mutants were much smaller than those elicited by the WT. Synteny of CLU5 is not only conserved in Colletotrichum spp. but also in additional species of Sordariomycetes including insect pathogens and saprophytes suggesting importance of CLU5 for fungal biology. Since CLU5a and CLU5d also occur in non-pathogenic fungi and since they are expressed prior to plant invasion and even in vegetative hyphae, the encoded proteins probably do not act primarily as effectors.
Collapse
Affiliation(s)
- Iris Eisermann
- Institut für Agrar- und Ernährungswissenschaften, Naturwissenschaftliche Fakultät III, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 3, D-06120, Halle (Saale), Germany
| | - Fabian Weihmann
- Institut für Agrar- und Ernährungswissenschaften, Naturwissenschaftliche Fakultät III, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 3, D-06120, Halle (Saale), Germany
| | - Jorrit-Jan Krijger
- Institut für Agrar- und Ernährungswissenschaften, Naturwissenschaftliche Fakultät III, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 3, D-06120, Halle (Saale), Germany
| | - Christian Kröling
- Institut für Agrar- und Ernährungswissenschaften, Naturwissenschaftliche Fakultät III, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 3, D-06120, Halle (Saale), Germany.,Sächsisches Landesamt für Umwelt, Landwirtschaft und Geologie, Abteilung Obst-, Gemüse- und Weinbau, August-Böckstiegel-Str. 1, D-01326, Dresden-Pillnitz, Germany
| | - Gerd Hause
- Biozentrum der Martin-Luther-Universität Halle-Wittenberg, Weinbergweg 22, D-06120, Halle (Saale), Germany
| | - Matthias Menzel
- Fraunhofer-Institut für Mikrostruktur von Werkstoffen und Systemen, Biologische und makromolekulare Materialien, Walter-Hülse-Str. 1, D-06120, Halle (Saale), Germany
| | - Silke Pienkny
- Department of Bioorganic Chemistry, Leibniz Institute of Plant Biochemistry, Weinberg 3, D-06120, Halle (Saale), Germany
| | - Andreas Kiesow
- Fraunhofer-Institut für Mikrostruktur von Werkstoffen und Systemen, Biologische und makromolekulare Materialien, Walter-Hülse-Str. 1, D-06120, Halle (Saale), Germany
| | - Holger B Deising
- Institut für Agrar- und Ernährungswissenschaften, Naturwissenschaftliche Fakultät III, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 3, D-06120, Halle (Saale), Germany
| | - Stefan G R Wirsel
- Institut für Agrar- und Ernährungswissenschaften, Naturwissenschaftliche Fakultät III, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 3, D-06120, Halle (Saale), Germany
| |
Collapse
|
11
|
Lin F, Krishnamoorthy P, Schubert V, Hause G, Heilmann M, Heilmann I. A dual role for cell plate-associated PI4Kβ in endocytosis and phragmoplast dynamics during plant somatic cytokinesis. EMBO J 2019; 38:embj.2018100303. [PMID: 30617084 DOI: 10.15252/embj.2018100303] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 11/29/2018] [Accepted: 12/04/2018] [Indexed: 11/09/2022] Open
Abstract
Plant cytokinesis involves membrane trafficking and cytoskeletal rearrangements. Here, we report that the phosphoinositide kinases PI4Kβ1 and PI4Kβ2 integrate these processes in Arabidopsis thaliana (Arabidopsis) roots. Cytokinetic defects of an Arabidopsis pi4kβ1 pi4kβ2 double mutant are accompanied by defects in membrane trafficking. Specifically, we show that trafficking of the proteins KNOLLE and PIN2 at the cell plate, clathrin recruitment, and endocytosis is impaired in pi4kβ1 pi4kβ2 double mutants, accompanied by unfused vesicles at the nascent cell plate and around cell wall stubs. Interestingly, pi4kβ1 pi4kβ2 plants also display ectopic overstabilization of phragmoplast microtubules, which guide membrane trafficking at the cell plate. The overstabilization of phragmoplasts in the double mutant coincides with mislocalization of the microtubule-associated protein 65-3 (MAP65-3), which cross-links microtubules and is a downstream target for inhibition by the MAP kinase MPK4. Based on similar cytokinetic defects of the pi4kβ1 pi4kβ2 and mpk4-2 mutants and genetic and physical interaction of PI4Kβ1 and MPK4, we propose that PI4Kβ and MPK4 influence localization and activity of MAP65-3, respectively, acting synergistically to control phragmoplast dynamics.
Collapse
Affiliation(s)
- Feng Lin
- Department of Cellular Biochemistry, Institute of Biochemistry and Biotechnology, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
| | - Praveen Krishnamoorthy
- Department of Cellular Biochemistry, Institute of Biochemistry and Biotechnology, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
| | - Veit Schubert
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Seeland, Germany
| | - Gerd Hause
- Biocenter, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
| | - Mareike Heilmann
- Department of Cellular Biochemistry, Institute of Biochemistry and Biotechnology, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
| | - Ingo Heilmann
- Department of Cellular Biochemistry, Institute of Biochemistry and Biotechnology, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
| |
Collapse
|
12
|
Impact of a high-protein diet during lactation on milk composition and offspring in a pig model. Eur J Nutr 2018; 58:3241-3253. [PMID: 30488185 DOI: 10.1007/s00394-018-1867-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Accepted: 11/21/2018] [Indexed: 10/27/2022]
Abstract
PURPOSE Early postnatal nutrition not only holds relevance to infant growth, but also determines the risk of developing obesity and chronic diseases such as diabetes type 2 and cardiovascular diseases in adulthood. It is suggested that a high-protein (HP) diet in early childhood can predispose children to obesity. However, data concerning possible alterations in milk composition and the development of the offspring in response to a maternal HP diet are currently not available. To address this question, we conducted a study using pigs as a model organism. METHODS At parturition, sows were assigned to two experimental groups. During lactation, the control group received a diet with a protein content of 16%, whereas the diet of the HP group contained 30% protein. After 28 days of lactation, samples were taken from sows and piglets for the quantification of free amino acids and other metabolites and for histology. RESULTS Serum and milk urea showed the most marked differences between the two groups of sows, whereas serum urea concentration in piglets did not differ. Here, we found that the intake of an HP diet changed a series of metabolites in sows, but had only small effects on milk composition and virtually no effects on growth in the offspring. Interestingly, maternal protein intake during lactation shapes the microbiome of the offspring. CONCLUSION From our current study, we conclude that even a very high maternal protein intake throughout lactation has no impact on growth and health parameters of the offspring.
Collapse
|
13
|
Brütting C, Crava CM, Schäfer M, Schuman MC, Meldau S, Adam N, Baldwin IT. Cytokinin transfer by a free-living mirid to Nicotiana attenuata recapitulates a strategy of endophytic insects. eLife 2018; 7:e36268. [PMID: 30014847 PMCID: PMC6059766 DOI: 10.7554/elife.36268] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 07/05/2018] [Indexed: 11/13/2022] Open
Abstract
Endophytic insects provide the textbook examples of herbivores that manipulate their host plant's physiology, putatively altering source/sink relationships by transferring cytokinins (CK) to create 'green islands' that increase the nutritional value of infested tissues. However, unambiguous demonstrations of CK transfer are lacking. Here we show that feeding by the free-living herbivore Tupiocoris notatus on Nicotiana attenuata is characterized by stable nutrient levels, increased CK levels and alterations in CK-related transcript levels in attacked leaves, in striking similarity to endophytic insects. Using 15N-isotope labeling, we demonstrate that the CK N6-isopentenyladenine (IP) is transferred from insects to plants via their oral secretions. In the field, T. notatus preferentially attacks leaves with transgenically increased CK levels; plants with abrogated CK-perception are less tolerant of T. notatus feeding damage. We infer that this free-living insect uses CKs to manipulate source/sink relationships to increase food quality and minimize the fitness consequences of its feeding.
Collapse
Affiliation(s)
- Christoph Brütting
- Department of Molecular EcologyMax Planck Institute for Chemical EcologyJenaGermany
| | - Cristina Maria Crava
- Department of Molecular EcologyMax Planck Institute for Chemical EcologyJenaGermany
| | - Martin Schäfer
- Department of Molecular EcologyMax Planck Institute for Chemical EcologyJenaGermany
| | - Meredith C Schuman
- Department of Molecular EcologyMax Planck Institute for Chemical EcologyJenaGermany
- German Centre for Integrative Biodiversity ResearchLeipzigGermany
| | - Stefan Meldau
- Department of Molecular EcologyMax Planck Institute for Chemical EcologyJenaGermany
| | - Nora Adam
- Department of Molecular EcologyMax Planck Institute for Chemical EcologyJenaGermany
- German Centre for Integrative Biodiversity ResearchLeipzigGermany
| | - Ian T Baldwin
- Department of Molecular EcologyMax Planck Institute for Chemical EcologyJenaGermany
| |
Collapse
|
14
|
Fan ZQ, Tan XL, Shan W, Kuang JF, Lu WJ, Chen JY. Characterization of a Transcriptional Regulator, BrWRKY6, Associated with Gibberellin-Suppressed Leaf Senescence of Chinese Flowering Cabbage. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:1791-1799. [PMID: 29400954 DOI: 10.1021/acs.jafc.7b06085] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Phytohormone gibberellin (GA) and plant-specific WRKY transcription factors (TFs) are reported to play important roles in leaf senescence. The association of WRKY TFs with GA-mediated leaf senescence of economically important leafy vegetables like Chinese flowering cabbage, however, remains largely unknown. In this study, we showed that exogenous application of GA3 suppressed Chinese flowering cabbage leaf senescence, with GA3-treated cabbages maintaining a higher level of maximum quantum yield (Fv/Fm) and total chlorophyll content. GA3 treatment also led to lower electrolyte leakage and expression level of a series of senescence-associated genes (SAGs) including BrSAG12 and BrSAG19, and chlorophyll catabolic genes (CCGs) BrPPH1, BrNYC1, and BrSGRs. In addition, higher transcription levels of GA biosynthetic genes BrKAO2 and BrGA20ox2 were found after GA3 treatment. More importantly, a GA-repressible, nuclear-localized WRKY TF, BrWRKY6, a homologue of the Arabidopsis AtWRKY6, was identified and characterized. BrWRKY6 was GA-repressible and localized in the nucleus. Further experiments revealed that BrWRKY6 repressed the expression of BrKAO2 and BrGA20ox2, while it activated BrSAG12, BrNYC1, and BrSGR1, through binding to their promoters via the W-box cis-element. Together, the novel GA-WRKY link reported in our study provides new insight into the transcriptional regulation of GA-suppressed leaf senescence in Chinese flowering cabbage.
Collapse
Affiliation(s)
- Zhong-Qi Fan
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, and Guangdong Vegetables Engineering Research Center, College of Horticulture, South China Agricultural University , Guangzhou 510642, China
| | - Xiao-Li Tan
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, and Guangdong Vegetables Engineering Research Center, College of Horticulture, South China Agricultural University , Guangzhou 510642, China
| | - Wei Shan
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, and Guangdong Vegetables Engineering Research Center, College of Horticulture, South China Agricultural University , Guangzhou 510642, China
| | - Jian-Fei Kuang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, and Guangdong Vegetables Engineering Research Center, College of Horticulture, South China Agricultural University , Guangzhou 510642, China
| | - Wang-Jin Lu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, and Guangdong Vegetables Engineering Research Center, College of Horticulture, South China Agricultural University , Guangzhou 510642, China
| | - Jian-Ye Chen
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, and Guangdong Vegetables Engineering Research Center, College of Horticulture, South China Agricultural University , Guangzhou 510642, China
| |
Collapse
|
15
|
Tan XL, Fan ZQ, Shan W, Yin XR, Kuang JF, Lu WJ, Chen JY. Association of BrERF72 with methyl jasmonate-induced leaf senescence of Chinese flowering cabbage through activating JA biosynthesis-related genes. HORTICULTURE RESEARCH 2018; 5:22. [PMID: 29736247 PMCID: PMC5928098 DOI: 10.1038/s41438-018-0028-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 02/23/2018] [Accepted: 02/25/2018] [Indexed: 05/05/2023]
Abstract
The ethylene response factor (ERF) and phytohormone jasmonate (JA) are reported to function in leaf senescence. The involvement of ERF in JA-mediated leaf senescence, however, needs to be elucidated. In the present work, we demonstrate a Chinese flowering cabbage ERF transcription factor (TF), BrERF72, that is associated with JA-promoted leaf senescence. Exogenous application of methyl jasmonate (MeJA)-accelerated leaf senescence of Chinese flowering cabbage, evidenced by the data that MeJA treatment led to the stronger reduction in the maximum quantum yield (Fv/Fm), photosynthetic electron transport rate (ETR), and total chlorophyll content, while significant induction in the expression of several senescence-associated genes (SAGs) including BrSAG12, BrSAG19, and chlorophyll catabolic genes (CCGs) BrPAO1, BrNYC1, BrPPH1, and BrSGR1. Increases in levels of endogenous JA and transcripts of JA biosynthetic genes BrLOX4, BrAOC3, and BrOPR3 were also found after MeJA treatment. BrERF72 was a MeJA-inducible, nucleus-localized protein, and possessed trans-activation ability. Transient overexpression of BrERF72 in tobacco leaves also promoted leaf senescence. More importantly, further experiments revealed that BrERF72 directly activated expression of BrLOX4, BrAOC3, and BrOPR3 through binding to their promoters via the GCC or DRE/CRT cis-element. Together, the novel JA-ERF association reported in our study uncovers a new insight into the transcriptional regulation of JA production mediated by ERF during JA-promoted leaf senescence in Chinese flowering cabbage.
Collapse
Affiliation(s)
- Xiao-li Tan
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables/Guangdong Vegetables Engineering Research Center, College of Horticulture, South China Agricultural University, 510642 Guangzhou, China
| | - Zhong-qi Fan
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables/Guangdong Vegetables Engineering Research Center, College of Horticulture, South China Agricultural University, 510642 Guangzhou, China
| | - Wei Shan
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables/Guangdong Vegetables Engineering Research Center, College of Horticulture, South China Agricultural University, 510642 Guangzhou, China
| | - Xue-ren Yin
- The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, College of Agriculture and Biotechnology, Zhejiang University, Zijingang Campus, 310058 Hangzhou, China
| | - Jian-fei Kuang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables/Guangdong Vegetables Engineering Research Center, College of Horticulture, South China Agricultural University, 510642 Guangzhou, China
| | - Wang-jin Lu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables/Guangdong Vegetables Engineering Research Center, College of Horticulture, South China Agricultural University, 510642 Guangzhou, China
| | - Jian-ye Chen
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables/Guangdong Vegetables Engineering Research Center, College of Horticulture, South China Agricultural University, 510642 Guangzhou, China
| |
Collapse
|
16
|
Oliveira-Garcia E, Deising HB. The Glycosylphosphatidylinositol Anchor Biosynthesis Genes GPI12, GAA1, and GPI8 Are Essential for Cell-Wall Integrity and Pathogenicity of the Maize Anthracnose Fungus Colletotrichum graminicola. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2016; 29:889-901. [PMID: 27937175 DOI: 10.1094/mpmi-09-16-0175-r] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Glycosylphosphatidylinositol (GPI) anchoring of proteins is one of the most common posttranslational modifications of proteins in eukaryotic cells and is important for associating proteins with the cell surface. In fungi, GPI-anchored proteins play essential roles in cross-linking of β-glucan cell-wall polymers and cell-wall rigidity. GPI-anchor synthesis is successively performed at the cytoplasmic and the luminal face of the ER membrane and involves approximately 25 proteins. While mutagenesis of auxiliary genes of this pathway suggested roles of GPI-anchored proteins in hyphal growth and virulence, essential genes of this pathway have not been characterized. Taking advantage of RNA interference (RNAi) we analyzed the function of the three essential genes GPI12, GAA1 and GPI8, encoding a cytoplasmic N-acetylglucosaminylphosphatidylinositol deacetylase, a metallo-peptide-synthetase and a cystein protease, the latter two representing catalytic components of the GPI transamidase complex. RNAi strains showed drastic cell-wall defects, resulting in exploding infection cells on the plant surface and severe distortion of in planta-differentiated infection hyphae, including formation of intrahyphal hyphae. Reduction of transcript abundance of the genes analyzed resulted in nonpathogenicity. We show here for the first time that the GPI synthesis genes GPI12, GAA1, and GPI8 are indispensable for vegetative development and pathogenicity of the causal agent of maize anthracnose, Colletotrichum graminicola.
Collapse
Affiliation(s)
- Ely Oliveira-Garcia
- 1 Martin-Luther-Universität Halle-Wittenberg, Naturwissenschaftliche Fakultät III, Institut für Agrar- und Ernährungswissenschaften, Phytopathologie und Pflanzenschutz, and
| | - Holger B Deising
- 1 Martin-Luther-Universität Halle-Wittenberg, Naturwissenschaftliche Fakultät III, Institut für Agrar- und Ernährungswissenschaften, Phytopathologie und Pflanzenschutz, and
- 2 Interdisziplinäres Zentrum für Nutzpflanzenforschung; Betty-Heimann-Str. 3. D-06120 Halle/Saale, Germany
| |
Collapse
|
17
|
Oliveira-Garcia E, Deising HB. Attenuation of PAMP-triggered immunity in maize requires down-regulation of the key β-1,6-glucan synthesis genes KRE5 and KRE6 in biotrophic hyphae of Colletotrichum graminicola. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2016; 87:355-75. [PMID: 27144995 DOI: 10.1111/tpj.13205] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Revised: 04/05/2016] [Accepted: 04/27/2016] [Indexed: 05/23/2023]
Abstract
In plants, pathogen defense is initiated by recognition of pathogen-associated molecular patterns (PAMPs) via plasma membrane-localized pattern-recognition receptors (PRRs). Fungal structural cell wall polymers such as branched β-glucans are essential for infection structure rigidity and pathogenicity, but at the same time represent PAMPs. Kre5 and Kre6 are key enzymes in β-1,6-glucan synthesis and formation of branch points of the β-glucan network. In spite of the importance of branched β-glucan for hyphal rigidity and plant-fungus interactions, neither the role of KRE5 and KRE6 in pathogenesis nor mechanisms allowing circumventing branched β-glucan-triggered immune responses are known. We functionally characterized KRE5 and KRE6 of the ascomycete Colletotrichum graminicola, a hemibiotroph that infects maize (Zea mays). After appressorial plant invasion, this fungus sequentially differentiates biotrophic and highly destructive necrotrophic hyphae. RNAi-mediated reduction of KRE5 and KRE6 transcript abundance caused appressoria to burst and swelling of necrotrophic hyphae, indicating that β-1,6-glucosidic bonds are essential in these cells. Live cell imaging employing KRE5:mCherry and KRE6:mCherry knock-in strains and probing of infection structures with a YFP-conjugated β-1,6-glucan-binding protein showed expression of these genes and exposure of β-1,6-glucan in conidia, appressoria and necrotrophic, but not in biotrophic hyphae. Overexpression of KRE5 and KRE6 in biotrophic hyphae led to activation of broad-spectrum plant defense responses, including papilla and H2 O2 formation, as well as transcriptional activation of several defense-related genes. Collectively, our results strongly suggest that down-regulation of synthesis and avoidance of exposure of branched β-1,3-β-1,6-glucan in biotrophic hyphae is required for attenuation of plant immune responses.
Collapse
Affiliation(s)
- Ely Oliveira-Garcia
- Martin-Luther-Universität Halle-Wittenberg, Naturwissenschaftliche Fakultät III, Institut für Agrar- und Ernährungswissenschaften, Phytopathologie und Pflanzenschutz, Betty-Heimann-Str. 3., D-06120, Halle/Saale, Germany
| | - Holger B Deising
- Martin-Luther-Universität Halle-Wittenberg, Naturwissenschaftliche Fakultät III, Institut für Agrar- und Ernährungswissenschaften, Phytopathologie und Pflanzenschutz, Betty-Heimann-Str. 3., D-06120, Halle/Saale, Germany.
- Martin-Luther-Universität Halle-Wittenberg, Interdisziplinäres Zentrum für Nutzpflanzenforschung, Betty-Heimann-Str. 3., D-06120, Halle/Saale, Germany.
| |
Collapse
|
18
|
Lange M, Weihmann F, Schliebner I, Horbach R, Deising HB, Wirsel SGR, Peiter E. The Transient Receptor Potential (TRP) Channel Family in Colletotrichum graminicola: A Molecular and Physiological Analysis. PLoS One 2016; 11:e0158561. [PMID: 27359114 PMCID: PMC4928787 DOI: 10.1371/journal.pone.0158561] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 06/19/2016] [Indexed: 12/02/2022] Open
Abstract
Calcium (Ca2+) is a universal second messenger in all higher organisms and centrally involved in the launch of responses to environmental stimuli. Ca2+ signals in the cytosol are initiated by the activation of Ca2+ channels in the plasma membrane and/or in endomembranes. Yeast (Saccharomyces cerevisiae) contains a Ca2+-permeable channel of the TRP family, TRPY1, which is localized in the vacuolar membrane and contributes to cytosolic free Ca2+ ([Ca2+]cyt) elevations, for example in response to osmotic upshock. A TRPY1 homologue in the rice blast fungus is known to be important for growth and pathogenicity. To determine the role of the TRP channel family in the maize pathogen Colletotrichum graminicola, proteins homologous to TRPY1 were searched. This identified not one, but four genes in the C. graminicola genome, which had putative orthologs in other fungi, and which we named CgTRPF1 through 4. The topology of the CgTRPF proteins resembled that of TRPY1, albeit with a variable number of transmembrane (TM) domains additional to the six-TM-domain core and a diverse arrangement of putatively Ca2+-binding acidic motifs. All CgTRPF genes were expressed in axenic culture and throughout the infection of maize. Like TRPY1, all TRPF proteins of C. graminicola were localized intracellularly, albeit three of them were found not in large vacuoles, but co-localized in vesicular structures. Deletion strains for the CgTRPF genes were not altered in processes thought to involve Ca2+ release from internal stores, i.e. spore germination, the utilization of complex carbon sources, and the generation of tip-focussed [Ca2+]cyt spikes. Heterologous expression of CgTRPF1 through 4 in a tryp1Δ yeast mutant revealed that none of the channels mediated the release of Ca2+ in response to osmotic upshock. Accordingly, aequorin-based [Ca2+]cyt measurements of C. graminicola showed that in this fungus, osmotic upshock-triggered [Ca2+]cyt elevations were generated entirely by influx of Ca2+ from the extracellular space. Cgtrpf mutants did not show pathogenicity defects in leaf infection assays. In summary, our study reveals major differences between different fungi in the contribution of TRP channels to Ca2+-mediated signal transduction.
Collapse
Affiliation(s)
- Mario Lange
- Plant Nutrition Laboratory, Institute of Agricultural and Nutritional Sciences (IAEW), Faculty of Natural Sciences III, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
- Interdisciplinary Centre for Crop Plant Research (IZN), Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Fabian Weihmann
- Phytopathology and Plant Protection, Institute of Agricultural and Nutritional Sciences (IAEW), Faculty of Natural Sciences III, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Ivo Schliebner
- Phytopathology and Plant Protection, Institute of Agricultural and Nutritional Sciences (IAEW), Faculty of Natural Sciences III, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
- Interdisciplinary Centre for Crop Plant Research (IZN), Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Ralf Horbach
- Phytopathology and Plant Protection, Institute of Agricultural and Nutritional Sciences (IAEW), Faculty of Natural Sciences III, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
- Interdisciplinary Centre for Crop Plant Research (IZN), Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Holger B. Deising
- Phytopathology and Plant Protection, Institute of Agricultural and Nutritional Sciences (IAEW), Faculty of Natural Sciences III, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
- Interdisciplinary Centre for Crop Plant Research (IZN), Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Stefan G. R. Wirsel
- Phytopathology and Plant Protection, Institute of Agricultural and Nutritional Sciences (IAEW), Faculty of Natural Sciences III, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
- Interdisciplinary Centre for Crop Plant Research (IZN), Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Edgar Peiter
- Plant Nutrition Laboratory, Institute of Agricultural and Nutritional Sciences (IAEW), Faculty of Natural Sciences III, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
- Interdisciplinary Centre for Crop Plant Research (IZN), Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| |
Collapse
|
19
|
Weihmann F, Eisermann I, Becher R, Krijger JJ, Hübner K, Deising HB, Wirsel SGR. Correspondence between symptom development of Colletotrichum graminicola and fungal biomass, quantified by a newly developed qPCR assay, depends on the maize variety. BMC Microbiol 2016; 16:94. [PMID: 27215339 PMCID: PMC4877754 DOI: 10.1186/s12866-016-0709-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 02/13/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Penetration attempts of the hemibiotroph Colletotrichum graminicola may activate PAMP-triggered immunity (PTI) on different cultivars of Zea mays to different extent. However, in most events, this does not prevent the establishment of a compatible pathogenic interaction. In this study, we investigate the extent to which the host variety influences PTI. Furthermore, we assess whether visual disease symptoms occurring on different maize varieties reliably reflect fungal biomass development in planta as determined by qPCR and GFP tracing. RESULTS Employing a set of four maize varieties, which were selected from a panel of 27 varieties, for in-depth assessment of pathogenesis of the wild type strain of C. graminicola, revealed considerable differences in susceptibility as evidenced by symptom severity that decreased from variety Golden Jubilee to Mikado to Farmtop to B73. However, a newly developed qPCR assay and microscopical observation of a GFP-labelled strain showed that disease symptoms are in some instances inconsistent when compared with other indicators of susceptibility. Of the four varieties assessed, either Golden Jubilee, Mikado and B73, or Golden Jubilee, Farmtop and B73 showed a direct correlation between symptom and fungal biomass development. In a pairwise comparison, however, Mikado and Farmtop showed an inverse correlation for these features. CONCLUSIONS The genotype of maize contributes to the severity of symptoms resulting from an infection with C. graminicola. Partially, this may be attributed to the extent of PTI activated in different varieties, as reflected by papilla formation. Furthermore, when evaluating the susceptibility of a variety, it should be considered that symptom severity must not have to reflect the extent of fungal growth in the infected tissue.
Collapse
Affiliation(s)
- Fabian Weihmann
- Institut für Agrar- und Ernährungswissenschaften, Naturwissenschaftliche Fakultät III, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 3, D-06120, Halle (Saale), Germany
| | - Iris Eisermann
- Institut für Agrar- und Ernährungswissenschaften, Naturwissenschaftliche Fakultät III, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 3, D-06120, Halle (Saale), Germany
| | - Rayko Becher
- Institut für Agrar- und Ernährungswissenschaften, Naturwissenschaftliche Fakultät III, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 3, D-06120, Halle (Saale), Germany
| | - Jorrit-Jan Krijger
- Institut für Agrar- und Ernährungswissenschaften, Naturwissenschaftliche Fakultät III, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 3, D-06120, Halle (Saale), Germany
| | - Konstantin Hübner
- Institut für Agrar- und Ernährungswissenschaften, Naturwissenschaftliche Fakultät III, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 3, D-06120, Halle (Saale), Germany.,Interdisziplinäres Zentrum für Nutzpflanzenforschung (IZN), Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 3, D-06120, Halle (Saale), Germany
| | - Holger B Deising
- Institut für Agrar- und Ernährungswissenschaften, Naturwissenschaftliche Fakultät III, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 3, D-06120, Halle (Saale), Germany.,Interdisziplinäres Zentrum für Nutzpflanzenforschung (IZN), Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 3, D-06120, Halle (Saale), Germany
| | - Stefan G R Wirsel
- Institut für Agrar- und Ernährungswissenschaften, Naturwissenschaftliche Fakultät III, Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 3, D-06120, Halle (Saale), Germany. .,Interdisziplinäres Zentrum für Nutzpflanzenforschung (IZN), Martin-Luther-Universität Halle-Wittenberg, Betty-Heimann-Str. 3, D-06120, Halle (Saale), Germany.
| |
Collapse
|
20
|
Kühne H, Hause G, Grundmann SM, Schutkowski A, Brandsch C, Stangl GI. Vitamin D receptor knockout mice exhibit elongated intestinal microvilli and increased ezrin expression. Nutr Res 2015; 36:184-92. [PMID: 26606857 DOI: 10.1016/j.nutres.2015.10.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 10/15/2015] [Accepted: 10/16/2015] [Indexed: 11/19/2022]
Abstract
In addition to its principle function as a calcium regulator, vitamin D can affect cell and tissue morphology. The intestine is an important target tissue of vitamin D, as it must ensure the efficient transport of nutrients across the epithelium while excluding the passage of harmful molecules and bacteria into the organism. These functions require a highly organized morphology, which may be modified by vitamin D deficiency. To elucidate the role of vitamin D in gut morphology and barrier function, we compared the enterocyte microstructures, gut permeability, and cytoskeletal and cell junction protein expression in vitamin D receptor (VDR) knockout (KO) and wild-type (WT) mice. We found that the duodenal epithelial cells in the VDR-KO mice had longer microvilli (+19%) than those of the WT mice (P < .05). Interestingly, microvilli elongation in the VDR-KO mice was associated with higher messenger RNA and protein expression of ezrin, which is involved in the regulation of microvillus morphogenesis. Intestinal tight junction width and permeability were assessed by measuring the fluorescein isothiocyanate dextran concentrations in plasma; the concentrations were comparable between the 2 groups of mice. We further observed a decrease in the messenger RNA and protein expression of the calcium-transporting tight junction protein claudin-2 in the VDR-KO mice compared with the WT mice (P < .05). In conclusion, the mice lacking VDR had longer enterocyte microvilli, likely as a result of increased ezrin expression. However, the morphology of the tight junctions and the intestinal permeability for large molecules were not affected.
Collapse
Affiliation(s)
- Hagen Kühne
- Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, 06120 Halle (Saale), Germany.
| | - Gerd Hause
- Biocenter of the Martin Luther University Halle-Wittenberg, 06120 Halle (Saale), Germany.
| | - Sarah M Grundmann
- Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, 06120 Halle (Saale), Germany.
| | - Alexandra Schutkowski
- Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, 06120 Halle (Saale), Germany.
| | - Corinna Brandsch
- Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, 06120 Halle (Saale), Germany.
| | - Gabriele I Stangl
- Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, 06120 Halle (Saale), Germany.
| |
Collapse
|
21
|
An F, Fan J, Li J, Li QX, Li K, Zhu W, Wen F, Carvalho LJCB, Chen S. Comparison of leaf proteomes of cassava (Manihot esculenta Crantz) cultivar NZ199 diploid and autotetraploid genotypes. PLoS One 2014; 9:e85991. [PMID: 24727655 PMCID: PMC3984080 DOI: 10.1371/journal.pone.0085991] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2013] [Accepted: 12/03/2013] [Indexed: 12/27/2022] Open
Abstract
Cassava polyploid breeding has drastically improved our knowledge on increasing root yield and its significant tolerance to stresses. In polyploid cassava plants, increases in DNA content highly affect cell volumes and anatomical structures. However, the mechanism of this effect is poorly understood. The purpose of the present study was to compare and validate the changes between cassava cultivar NZ199 diploid and autotetraploid at proteomic levels. The results showed that leaf proteome of cassava cultivar NZ199 diploid was clearly differentiated from its autotetraploid genotype using 2-DE combined MS technique. Sixty-five differential protein spots were seen in 2-DE image of autotetraploid genotype in comparison with that of diploid. Fifty-two proteins were identified by MALDI-TOF-MS/MS, of which 47 were up-regulated and 5 were down-regulated in autotetraploid genotype compared with diploid genotype. The classified functions of 32 up-regulated proteins were associated with photosynthesis, defense system, hydrocyanic acid (HCN) metabolism, protein biosynthesis, chaperones, amino acid metabolism and signal transduction. The remarkable variation in photosynthetic activity, HCN content and resistance to salt stress between diploid and autotetraploid genotypes is closely linked with expression levels of proteomic profiles. The analysis of protein interaction networks indicated there are direct interactions between the 15 up-regulation proteins involved in the pathways described above. This work provides an insight into understanding the protein regulation mechanism of cassava polyploid genotype, and gives a clue to improve cassava polyploidy breeding in increasing photosynthesis and resistance efficiencies.
Collapse
Affiliation(s)
- Feifei An
- Tropical Crops Genetic Resources Institute, Chinese Academy of Tropical Agricultural Sciences/Key Laboratory of Ministry of Agriculture for Germplasm Resources Conservation and Utilization of Cassava, Hainan, China
| | - Jie Fan
- Tropical Crops Genetic Resources Institute, Chinese Academy of Tropical Agricultural Sciences/Key Laboratory of Ministry of Agriculture for Germplasm Resources Conservation and Utilization of Cassava, Hainan, China
| | - Jun Li
- Analysis and Testing Center, Jiangsu University, Jiangsu, China
| | - Qing X. Li
- Proteomics Core Facility, Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, Manoa, Hawaii, United States of America
| | - Kaimian Li
- Tropical Crops Genetic Resources Institute, Chinese Academy of Tropical Agricultural Sciences/Key Laboratory of Ministry of Agriculture for Germplasm Resources Conservation and Utilization of Cassava, Hainan, China
- * E-mail: (KL); (SC)
| | - Wenli Zhu
- Tropical Crops Genetic Resources Institute, Chinese Academy of Tropical Agricultural Sciences/Key Laboratory of Ministry of Agriculture for Germplasm Resources Conservation and Utilization of Cassava, Hainan, China
| | - Feng Wen
- Guangxi Sub-tropical Crop Research Institute, Nanning, China
| | | | - Songbi Chen
- Tropical Crops Genetic Resources Institute, Chinese Academy of Tropical Agricultural Sciences/Key Laboratory of Ministry of Agriculture for Germplasm Resources Conservation and Utilization of Cassava, Hainan, China
- * E-mail: (KL); (SC)
| |
Collapse
|
22
|
Albarouki E, Schafferer L, Ye F, von Wirén N, Haas H, Deising HB. Biotrophy-specific downregulation of siderophore biosynthesis in Colletotrichum graminicola is required for modulation of immune responses of maize. Mol Microbiol 2014; 92:338-55. [PMID: 24674132 PMCID: PMC4235341 DOI: 10.1111/mmi.12561] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/18/2014] [Indexed: 12/01/2022]
Abstract
The hemibiotrophic maize pathogen Colletotrichum graminicola synthesizes one intracellular and three secreted siderophores. eGFP fusions with the key siderophore biosynthesis gene, SID1, encoding l-ornithine-N(5) -monooxygenase, suggested that siderophore biosynthesis is rigorously downregulated specifically during biotrophic development. In order to investigate the role of siderophores during vegetative development and pathogenesis, SID1, which is required for synthesis of all siderophores, and the non-ribosomal peptide synthetase gene NPS6, synthesizing secreted siderophores, were deleted. Mutant analyses revealed that siderophores are required for vegetative growth under iron-limiting conditions, conidiation, ROS tolerance, and cell wall integrity. Δsid1 and Δnps6 mutants were hampered in formation of melanized appressoria and impaired in virulence. In agreement with biotrophy-specific downregulation of siderophore biosynthesis, Δsid1 and Δnps6 strains were not affected in biotrophic development, but spread of necrotrophic hyphae was reduced. To address the question why siderophore biosynthesis is specifically downregulated in biotrophic hyphae, maize leaves were infiltrated with siderophores. Siderophore infiltration alone did not induce defence responses, but formation of biotrophic hyphae in siderophore-infiltrated leaves caused dramatically increased ROS formation and transcriptional activation of genes encoding defence-related peroxidases and PR proteins. These data suggest that fungal siderophores modulate the plant immune system.
Collapse
Affiliation(s)
- Emad Albarouki
- Martin-Luther-Universität Halle-Wittenberg, Interdisziplinäres Zentrum für Nutzpflanzenforschung (IZN), Betty-Heimann-Str. 3, D-06120, Halle (Saale), Germany; Martin-Luther-Universität Halle-Wittenberg, Institut für Agrar- und Ernährungswissenschaften, Phytopathologie und Pflanzenschutz, Betty-Heimann-Str. 3, D-06120, Halle (Saale), Germany
| | | | | | | | | | | |
Collapse
|
23
|
Lapin D, Van den Ackerveken G. Susceptibility to plant disease: more than a failure of host immunity. TRENDS IN PLANT SCIENCE 2013; 18:546-54. [PMID: 23790254 DOI: 10.1016/j.tplants.2013.05.005] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2013] [Revised: 05/15/2013] [Accepted: 05/21/2013] [Indexed: 05/23/2023]
Abstract
Susceptibility to infectious diseases caused by pathogens affects most plants in their natural habitat and leads to yield losses in agriculture. However, plants are not helpless because their immune system can deal with the vast majority of attackers. Nevertheless, adapted pathogens are able to circumvent or avert host immunity making plants susceptible to these uninvited guests. In addition to the failure of the plant immune system, there are other host processes that contribute to plant disease susceptibility. In this review, we discuss recent studies that show the active role played by the host in supporting disease, focusing mainly on biotrophic stages of infection. Plants attract pathogens, enable their entry and accommodation, and facilitate nutrient provision.
Collapse
Affiliation(s)
- Dmitry Lapin
- Plant-Microbe Interactions, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | | |
Collapse
|
24
|
Albarouki E, Deising HB. Infection structure-specific reductive iron assimilation is required for cell wall integrity and full virulence of the maize pathogen Colletotrichum graminicola. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2013; 26:695-708. [PMID: 23639025 DOI: 10.1094/mpmi-01-13-0003-r] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Ferroxidases are essential components of the high-affinity reductive iron assimilation pathway in fungi. Two ferroxidase genes, FET3-1 and FET3-2, have been identified in the genome of the maize anthracnose fungus Colletotrichum graminicola. Complementation of growth defects of the ferroxidase-deficient Saccharomyces cerevisiae strain Δfet3fet4 showed that both Fet3-1 and Fet3-2 of C. graminicola represent functional ferroxidases. Expression of enhanced green fluorescent protein fusions in yeast and C. graminicola indicated that both ferroxidase proteins localize to the plasma membrane. Transcript abundance of FET3-1 increased dramatically under iron-limiting conditions but those of FET3-2 were hardly detectable. Δfet3-1 and Δfet3-2 single as well as Δfet3-1/2 double-deletion strains were generated. Under iron-sufficient or deficient conditions, vegetative growth rates of these strains did not significantly differ from that of the wild type but Δfet3-1 and Δfet3-1/2 strains showed increased sensitivity to reactive oxygen species. Furthermore, under iron-limiting conditions, appressoria of Δfet3-1 and Δfet3-1/2 strains showed significantly reduced transcript abundance of a class V chitin synthase and exhibited severe cell wall defects. Infection assays on intact and wounded maize leaves, quantitative data of infection structure differentiation, and infection stage-specific expression of FET3-1 showed that reductive iron assimilation is required for appressorial penetration, biotrophic development, and full virulence.
Collapse
Affiliation(s)
- Emad Albarouki
- Martin-Luther-Universitat Halle-Wittenberg, Halle, Germany
| | | |
Collapse
|
25
|
Jiang CJ, Shimono M, Sugano S, Kojima M, Liu X, Inoue H, Sakakibara H, Takatsuji H. Cytokinins act synergistically with salicylic acid to activate defense gene expression in rice. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2013; 26:287-96. [PMID: 23234404 DOI: 10.1094/mpmi-06-12-0152-r] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Hormone crosstalk is pivotal in plant-pathogen interactions. Here, we report on the accumulation of cytokinins (CK) in rice seedlings after infection of blast fungus Magnaporthe oryzae and its potential significance in rice-M. oryzae interaction. Blast infection to rice seedlings increased levels of N(6)-(Δ(2)-isopentenyl) adenine (iP), iP riboside (iPR), and iPR 5'-phosphates (iPRP) in leaf blades. Consistent with this, CK signaling was activated around the infection sites, as shown by histochemical staining for β-glucuronidase activity driven by a CK-responsive OsRR6 promoter. Diverse CK species were also detected in the hyphae (mycelium), conidia, and culture filtrates of blast fungus, indicating that M. oryzae is capable of production as well as hyphal secretion of CK. Co-treatment of leaf blades with CK and salicylic acid (SA), but not with either one alone, markedly induced pathogenesis-related genes OsPR1b and probenazole-induced protein 1 (PBZ1). These effects were diminished by RNAi-knockdown of OsNPR1 or WRKY45, the key regulators of the SA signaling pathway in rice, indicating that the effects of CK depend on these two regulators. Taken together, our data imply a coevolutionary rice-M. oryzae interaction, wherein M. oryzae probably elevates rice CK levels for its own benefits such as nutrient translocation. Rice plants, on the other hand, sense it as an infection signal and activate defense reactions through the synergistic action with SA.
Collapse
Affiliation(s)
- Chang-Jie Jiang
- National Institute of Agrobiological Sciences, Tsukuba, Japan.
| | | | | | | | | | | | | | | |
Collapse
|
26
|
Behr M, Motyka V, Weihmann F, Malbeck J, Deising HB, Wirsel SGR. Remodeling of cytokinin metabolism at infection sites of Colletotrichum graminicola on maize leaves. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2012; 25:1073-82. [PMID: 22746825 DOI: 10.1094/mpmi-01-12-0012-r] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
When inoculated onto maize leaves at the onset of senescence, the hemibiotroph Colletotrichum graminicola causes green islands that are surrounded by senescing tissue. Taking advantage of green islands as indicators of sites of the establishment of successful infection and of advanced high-performance liquid chromatography tandem mass spectrometry methodology, we analyzed changes in the patterns and levels of cytokinins (CK) at high spatial and analytical resolution. Twenty individual CK were detected in green islands. Levels of cis-zeatin-9-riboside and cis-zeatin-9-riboside-5'-monophosphate increased drastically, whereas that of the most prominent CK, cis-zeatin-O-glucoside, decreased. The fungus likely performed these conversions because corresponding activities were also detected in in vitro cultures amended with CK. We found no evidence that C. graminicola is able to synthesize CK entirely de novo in minimal medium but, after adding dimethylallyl diphosphate, a precursor of CK biosynthesis occurring in plants, a series of trans-zeatin isoforms (i.e., trans-zeatin-9-riboside-5'-monophosphate, trans-zeatin-9-riboside, and trans-zeatin) was formed. After applying CK onto uninfected leaves, transcripts of marker genes for senescence, photosynthesis, and assimilate distribution were measured by quantitative reverse-transcribed polymerase chain reaction; furthermore, pulse-amplitude modulation chlorophyll fluorometry and single-photon avalanche diode analyses were conducted. These experiments suggested that modulation of CK metabolism at the infection site affects host physiology.
Collapse
Affiliation(s)
- Michael Behr
- Institute of Agricultural and Nutritional Sciences, Martin-Luther-University, Halle, Germany
| | | | | | | | | | | |
Collapse
|
27
|
Vargas WA, Martín JMS, Rech GE, Rivera LP, Benito EP, Díaz-Mínguez JM, Thon MR, Sukno SA. Plant defense mechanisms are activated during biotrophic and necrotrophic development of Colletotricum graminicola in maize. PLANT PHYSIOLOGY 2012; 158:1342-58. [PMID: 22247271 PMCID: PMC3291271 DOI: 10.1104/pp.111.190397] [Citation(s) in RCA: 114] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Accepted: 01/11/2012] [Indexed: 05/18/2023]
Abstract
Hemibiotrophic plant pathogens first establish a biotrophic interaction with the host plant and later switch to a destructive necrotrophic lifestyle. Studies of biotrophic pathogens have shown that they actively suppress plant defenses after an initial microbe-associated molecular pattern-triggered activation. In contrast, studies of the hemibiotrophs suggest that they do not suppress plant defenses during the biotrophic phase, indicating that while there are similarities between the biotrophic phase of hemibiotrophs and biotrophic pathogens, the two lifestyles are not analogous. We performed transcriptomic, histological, and biochemical studies of the early events during the infection of maize (Zea mays) with Colletotrichum graminicola, a model pathosystem for the study of hemibiotrophy. Time-course experiments revealed that mRNAs of several defense-related genes, reactive oxygen species, and antimicrobial compounds all begin to accumulate early in the infection process and continue to accumulate during the biotrophic stage. We also discovered the production of maize-derived vesicular bodies containing hydrogen peroxide targeting the fungal hyphae. We describe the fungal respiratory burst during host infection, paralleled by superoxide ion production in specific fungal cells during the transition from biotrophy to a necrotrophic lifestyle. We also identified several novel putative fungal effectors and studied their expression during anthracnose development in maize. Our results demonstrate a strong induction of defense mechanisms occurring in maize cells during C. graminicola infection, even during the biotrophic development of the pathogen. We hypothesize that the switch to necrotrophic growth enables the fungus to evade the effects of the plant immune system and allows for full fungal pathogenicity.
Collapse
Affiliation(s)
- Walter A. Vargas
- Centro Hispanoluso de Investigaciones Agrarias, Department of Microbiology and Genetics, University of Salamanca, 37185 Villamayor, Spain
| | - José M. Sanz Martín
- Centro Hispanoluso de Investigaciones Agrarias, Department of Microbiology and Genetics, University of Salamanca, 37185 Villamayor, Spain
| | - Gabriel E. Rech
- Centro Hispanoluso de Investigaciones Agrarias, Department of Microbiology and Genetics, University of Salamanca, 37185 Villamayor, Spain
| | - Lina P. Rivera
- Centro Hispanoluso de Investigaciones Agrarias, Department of Microbiology and Genetics, University of Salamanca, 37185 Villamayor, Spain
| | - Ernesto P. Benito
- Centro Hispanoluso de Investigaciones Agrarias, Department of Microbiology and Genetics, University of Salamanca, 37185 Villamayor, Spain
| | - José M. Díaz-Mínguez
- Centro Hispanoluso de Investigaciones Agrarias, Department of Microbiology and Genetics, University of Salamanca, 37185 Villamayor, Spain
| | - Michael R. Thon
- Centro Hispanoluso de Investigaciones Agrarias, Department of Microbiology and Genetics, University of Salamanca, 37185 Villamayor, Spain
| | - Serenella A. Sukno
- Centro Hispanoluso de Investigaciones Agrarias, Department of Microbiology and Genetics, University of Salamanca, 37185 Villamayor, Spain
| |
Collapse
|
28
|
Lingner U, Münch S, Deising HB, Sauer N. Hexose transporters of a hemibiotrophic plant pathogen: functional variations and regulatory differences at different stages of infection. J Biol Chem 2011; 286:20913-22. [PMID: 21502323 PMCID: PMC3121522 DOI: 10.1074/jbc.m110.213678] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Revised: 03/26/2011] [Indexed: 11/06/2022] Open
Abstract
Plant pathogenic fungi use a wide range of different strategies to gain access to the carbon sources of their host plants. The hemibiotrophic maize pathogen Colletotrichum graminicola (teleomorph Glomerella graminicola) colonizes its host plants, and, after a short biotrophic phase, switches to destructive, necrotrophic development. Here we present the identification of five hexose transporter genes from C. graminicola, CgHXT1 to CgHXT5, the functional characterization of the encoded proteins, and detailed expression studies for these genes during vegetative and pathogenic development. Whereas CgHXT4 is expressed under all conditions analyzed, transcript abundances of CgHXT1 and CgHXT3 are transiently up-regulated during the biotrophic phase, and CgHXT2 and CgHXT5 are expressed exclusively during necrotrophic development. Analyses of the encoded proteins characterized CgHXT5 as a low-affinity/high-capacity hexose transporter with a narrow substrate specificity for glucose and mannose. In contrast, CgHXT1 to CgHXT3 are high affinity/low capacity transporters that also accept other substrates, including fructose, galactose, or xylose. CgHXT4, the largest of the identified proteins, has only little transport activity and may function as a sugar sensor. Phylogenetic studies revealed hexose transporters closely related to the five CgHXT proteins also in other pathogenic fungi suggesting conserved functions of these proteins during fungal pathogenesis.
Collapse
Affiliation(s)
- Ulrike Lingner
- From the Molecular Plant Physiology, Friedrich-Alexander-University Erlangen-Nuremberg, Staudtstrasse 5, D-91058 Erlangen, Germany
| | - Steffen Münch
- the Phytopathology and Plant Protection, Martin-Luther-University Halle-Wittenberg, Betty-Heimann-Strasse 3, D-06120 Halle (Saale), Germany, and
| | - Holger B. Deising
- the Phytopathology and Plant Protection, Martin-Luther-University Halle-Wittenberg, Betty-Heimann-Strasse 3, D-06120 Halle (Saale), Germany, and
- the Interdisciplinary Center for Crop Plant Research, Martin-Luther-University Halle-Wittenberg, Betty-Heimann-Strasse 3, D-06120 Halle (Saale), Germany
| | - Norbert Sauer
- From the Molecular Plant Physiology, Friedrich-Alexander-University Erlangen-Nuremberg, Staudtstrasse 5, D-91058 Erlangen, Germany
- the Erlangen Center of Plant Science (CROPS), Friedrich-Alexander University of Erlangen-Nuremberg, Staudtstrasse 5
| |
Collapse
|
29
|
Horbach R, Navarro-Quesada AR, Knogge W, Deising HB. When and how to kill a plant cell: infection strategies of plant pathogenic fungi. JOURNAL OF PLANT PHYSIOLOGY 2011; 168:51-62. [PMID: 20674079 DOI: 10.1016/j.jplph.2010.06.014] [Citation(s) in RCA: 188] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2010] [Revised: 06/16/2010] [Accepted: 06/18/2010] [Indexed: 05/23/2023]
Abstract
Fungi cause severe diseases on a broad range of crop and ornamental plants, leading to significant economical losses. Plant pathogenic fungi exhibit a huge variability in their mode of infection, differentiation and function of infection structures and nutritional strategy. In this review, advances in understanding mechanisms of biotrophy, necrotrophy and hemibiotrophic lifestyles are described. Special emphasis is given to the biotrophy-necrotrophy switch of hemibiotrophic pathogens, and to biosynthesis, chemical diversity and mode of action of various fungal toxins produced during the infection process.
Collapse
Affiliation(s)
- Ralf Horbach
- Martin-Luther-University Halle-Wittenberg, Faculty of Natural Sciences III, Institute for Agricultural and Nutritional Sciences, Phytopathology and Plant Protection, Betty-Heimann-Strasse 3, Halle (Saale), Germany
| | | | | | | |
Collapse
|