Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 165
Filtrar
1.
Science ; 383(6684): 732-739, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38359129

RESUMO

Polygalacturonase-inhibiting proteins (PGIPs) interact with pathogen-derived polygalacturonases to inhibit their virulence-associated plant cell wall-degrading activity but stimulate immunity-inducing oligogalacturonide production. Here we show that interaction between Phaseolus vulgaris PGIP2 (PvPGIP2) and Fusarium phyllophilum polygalacturonase (FpPG) enhances substrate binding, resulting in inhibition of the enzyme activity of FpPG. This interaction promotes FpPG-catalyzed production of long-chain immunoactive oligogalacturonides, while diminishing immunosuppressive short oligogalacturonides. PvPGIP2 binding creates a substrate binding site on PvPGIP2-FpPG, forming a new polygalacturonase with boosted substrate binding activity and altered substrate preference. Structure-based engineering converts a putative PGIP that initially lacks FpPG-binding activity into an effective FpPG-interacting protein. These findings unveil a mechanism for plants to transform pathogen virulence activity into a defense trigger and provide proof of principle for engineering PGIPs with broader specificity.


Assuntos
Fusarium , Phaseolus , Imunidade Vegetal , Proteínas de Plantas , Poligalacturonase , Fatores de Virulência , Imunidade Inata , Proteínas de Plantas/metabolismo , Poligalacturonase/metabolismo , Fatores de Virulência/metabolismo , Fusarium/imunologia , Fusarium/patogenicidade , Phaseolus/imunologia , Phaseolus/microbiologia
3.
Mol Plant ; 16(5): 865-881, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-37002606

RESUMO

Most organisms adjust their development according to the environmental conditions. For the majority, this implies the sensing of alterations to cell walls caused by different cues. Despite the relevance of this process, few molecular players involved in cell wall sensing are known and characterized. Here, we show that the wall-associated kinase-like protein RESISTANCE TO FUSARIUM OXYSPORUM 1 (RFO1) is required for plant growth and early defense against Fusarium oxysporum and functions by sensing changes in the pectin methylation levels in the cell wall. The RFO1 dwell time at the plasma membrane is affected by the pectin methylation status at the cell wall, regulating MITOGEN-ACTIVATED PROTEIN KINASE and gene expression. We show that the extracellular domain of RFO1 binds de-methylated pectin in vitro, whose distribution in the cell wall is altered during F. oxysporum infection. Further analyses also indicate that RFO1 is required for the BR-dependent plant growth alteration in response to inhibition of pectin de-methyl-esterase activity at the cell wall. Collectively, our work demonstrates that RFO1 is a sensor of the pectin methylation status that plays a unique dual role in plant growth and defense against vascular pathogens.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fusarium , Pectinas , Imunidade Vegetal , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/imunologia , Arabidopsis/microbiologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Parede Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Metilação , Pectinas/metabolismo , Proteínas Quinases/metabolismo , Fusarium/imunologia
4.
Int J Mol Sci ; 23(4)2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35216128

RESUMO

The plant mitogen-activated protein kinase (MAPK) cascade plays an important role in mediating responses to biotic and abiotic stresses and is the main pathway through which extracellular stimuli are transduced intracellularly as signals. Our previous research showed that the GhMKK6-GhMPK4 cascade signaling pathway plays an important role in cotton immunity. To further analyze the role and regulatory mechanism of the GhMKK6-GhMPK4 cascade signaling pathway in cotton resistance to Fusarium wilt, we functionally analyzed GhMPK4. Our results show that silencing GhMPK4 reduces cotton tolerance to Fusarium wilt and reduces the expression of several resistance genes. Further experiments revealed that GhMPK4 is similar to GhMKK6, both of whose overexpression cause unfavorable cotton immune response characteristics. By using a yeast two-hybrid screening library and performing a bioinformatics analysis, we screened and identified a negative regulator of the MAPK kinase-protein phosphatase AP2C1. Through the functional analysis of AP2C1, it was found that, after being silenced, GhAP2C1 increased resistance to Fusarium wilt, but GhAP2C1 overexpression caused sensitivity to Fusarium wilt. These findings show that GhAP2C1 interacts together with GhMPK4 to regulate the immune response of cotton to Fusarium oxysporum, which provides important data for functionally analyzing and studying the feedback regulatory mechanism of the MAPK cascade and helps to clarify the regulatory mechanism through which the MAPK cascade acts in response to pathogens.


Assuntos
Fusarium/imunologia , Gossypium/imunologia , Gossypium/metabolismo , Imunidade/imunologia , Fosfoproteínas Fosfatases/metabolismo , Doenças das Plantas/imunologia , Proteínas de Plantas/metabolismo , Resistência à Doença/imunologia , Sistema de Sinalização das MAP Quinases/imunologia , Transdução de Sinais/imunologia
5.
Mol Immunol ; 142: 120-129, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34979452

RESUMO

Fungal diseases of fish are a significant economic problem in aquaculture. Using high-throughput expression analysis, we identified potential transcript markers in primary head kidney and secondary embryonic cells from salmonid fish after stimulation with the inactivated fungi Mucor hiemalis and Fusarium aveneacium and with purified fungal molecular patterns. The transcript levels of most of the 45 selected genes were altered in head-kidney cells after 24 h of stimulation with fungal antigens. Stimulation with the inactivated fungus M. hiemalis induced the most pronounced transcriptional changes, including the pathogen receptor-encoding genes CLEC18A and TLR22, the cytokine-encoding genes IL6 and TNF, and the gene encoding the antimicrobial peptide LEAP2. In parallel, we analyzed the total GlcNAcylation status of embryonic salmonid cells with or without stimulation with inactivated fungi. O-GlcNAcylation modulates gene expression, intracellular protein, and signal activity, but we detected no significant differences after a 3-h stimulation. A pathway analysis tool identified the "apoptosis of leukocytes" based on the expression profile 24 h after fungal stimulation. Fluorescence microscopy combined with flow cytometry revealed apoptosis in 50 % of head-kidney leukocytes after 3 h stimulation with M. hiemalis, but this level decreased by > 5% after 24 h of stimulation. The number of apoptotic cells significantly increased in all blood cells after a 3-h stimulation with fungal molecular patterns compared to unstimulated controls. This in vitro approach identified transcript-based parameters that were strongly modulated by fungal infections of salmonid fish.


Assuntos
Acetilglucosamina/química , Fusarium/imunologia , Mucor/imunologia , Micoses/imunologia , Oncorhynchus mykiss/microbiologia , Salmão/microbiologia , Animais , Peptídeos Catiônicos Antimicrobianos/genética , Apoptose/fisiologia , Doenças dos Peixes/microbiologia , Regulação da Expressão Gênica no Desenvolvimento/genética , Rim Cefálico/metabolismo , Interleucina-6/genética , Lectinas Tipo C/genética , Processamento de Proteína Pós-Traducional , Receptor 3 Toll-Like/genética , Fator de Necrose Tumoral alfa/genética
6.
J Plant Physiol ; 269: 153593, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34915227

RESUMO

Fungal infections of cereal crops pose a significant risk to global food security through reduced grain production and quality, as well as contamination of animal feed and human products for consumption. To combat fungal disease, we need to understand how the pathogen adapts and survives within the hostile environment of the host and how the host's defense response can be modulated for protection from disease. Such investigations offer insight into fungal pathogenesis, host immunity, the development of resistance, and mechanisms of action for currently-used control strategies. Mass spectrometry-based proteomics provides a technologically-advanced platform to define differences among fungal pathogens and their hosts at the protein level, supporting the discovery of proteins critical for disease, and uncovering novel host responses driving susceptibly or resistance of the host. In this Review, we explore the role of mass spectrometry-based proteomics in defining the intricate relationship between a pathogen and host during fungal disease of cereal crops with a focus on recent discoveries derived from the globally-devastating diseases of Fusarium head blight, Rice blast, and Powdery mildew. We highlight advances made for each of these diseases and discuss opportunities to extrapolate findings to further our fight against fungal pathogens on a global scale.


Assuntos
Produtos Agrícolas/imunologia , Produtos Agrícolas/microbiologia , Grão Comestível/microbiologia , Fusarium/imunologia , Fusarium/patogenicidade , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Grão Comestível/imunologia , Proteômica
7.
Sci Rep ; 11(1): 18948, 2021 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-34556705

RESUMO

Plant defensins are small, basic peptides that have a characteristic three-dimensional folding pattern which is stabilized by four disulfide bridges. We show here that Arabidopsis contains in addition to the proper plant defensins a group of 9 plant defensin-like (PdfL) genes. They are all expressed at low levels while GUS fusions of the promoters showed expression in most tissues with only minor differences. We produced two of the encoded peptides in E. coli and tested the antimicrobial activity in vitro. Both were highly active against fungi but had lower activity against bacteria. At higher concentrations hyperbranching and swollen tips, which are indicative of antimicrobial activity, were induced in Fusarium graminearum by both peptides. Overexpression lines for most PdfL genes were produced using the 35S CaMV promoter to study their possible in planta function. With the exception of PdfL4.1 these lines had enhanced resistance against F. oxysporum. All PDFL peptides were also transiently expressed in Nicotiana benthamiana leaves with agroinfiltration using the pPZP3425 vector. In case of PDFL1.4 this resulted in complete death of the infiltrated tissues after 7 days. All other PDFLs resulted only in various degrees of small necrotic lesions. In conclusion, our results show that at least some of the PdfL genes could function in plant resistance.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/imunologia , Defensinas/metabolismo , Arabidopsis/genética , Arabidopsis/microbiologia , Proteínas de Arabidopsis/genética , Defensinas/genética , Resistência à Doença , Fusarium/imunologia , Regulação da Expressão Gênica de Plantas/imunologia , Interações Hospedeiro-Patógeno , Plantas Geneticamente Modificadas , /imunologia , /metabolismo
8.
Sci Rep ; 11(1): 12452, 2021 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-34127703

RESUMO

Cyclotides are cyclic peptides produced by plants. Due to their insecticidal properties, they are thought to be involved in host defense. Violets produce complex mixtures of cyclotides, that are characteristic for each species and variable in different environments. Herein, we utilized mass spectrometry (LC-MS, MALDI-MS), transcriptomics and biological assays to investigate the diversity, differences in cyclotide expression based on species and different environment, and antimicrobial activity of cyclotides found in violets from the Canary Islands. A wide range of different habitats can be found on these islands, from subtropical forests to dry volcano peaks at high altitudes. The islands are inhabited by the endemic Viola palmensis, V. cheiranthifolia, V. anagae and the common V. odorata. The number of cyclotides produced by a given species varied in plants from different environments. The highest diversity was noted in V. anagae which resides in subtropical forest and the lowest in V. cheiranthifolia from the Teide volcano. Transcriptome sequencing and LC-MS were used to identify 23 cyclotide sequences from V. anagae. Cyclotide extracts exhibited antifungal activities with the lowest minimal inhibitory concentrations noted for V. anagae (15.62 µg/ml against Fusarium culmorum). The analysis of the relative abundance of 30 selected cyclotides revealed patterns characteristic to both species and populations, which can be the result of genetic variability or environmental conditions in different habitats. The current study exemplifies how plants tailor their host defense peptides for various habitats, and the usefulness of cyclotides as markers for chemosystematics.


Assuntos
Ciclotídeos/imunologia , Fusarium/imunologia , Proteínas de Plantas/imunologia , Viola/imunologia , Cromatografia Líquida , Ciclotídeos/análise , Ciclotídeos/genética , Ciclotídeos/metabolismo , Perfilação da Expressão Gênica , Geografia , Interações Hospedeiro-Patógeno/imunologia , Testes de Sensibilidade Microbiana , Proteínas de Plantas/análise , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Espanha , Especificidade da Espécie , Viola/classificação , Viola/microbiologia
9.
Molecules ; 26(7)2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33804901

RESUMO

New strategies of control need to be developed with the aim of economic and environmental sustainability in plant and crop protection. Metabolomics is an excellent platform for both understanding the complex plant-pathogen interactions and unraveling new chemical control strategies. GC-MS-based metabolomics, along with a phytohormone analysis of a compatible and incompatible interaction between tomato plants and Fusarium oxysporum f. sp. lycopersici, revealed the specific volatile chemical composition and the plant signals associated with them. The susceptible tomato plants were characterized by the over-emission of methyl- and ethyl-salicylate as well as some fatty acid derivatives, along with an activation of salicylic acid and abscisic acid signaling. In contrast, terpenoids, benzenoids, and 2-ethylhexanoic acid were differentially emitted by plants undergoing an incompatible interaction, together with the activation of the jasmonic acid (JA) pathway. In accordance with this response, a higher expression of several genes participating in the biosynthesis of these volatiles, such as MTS1, TomloxC,TomloxD, and AOS, as well as JAZ7, a JA marker gene, was found to be induced by the fungus in these resistant plants. The characterized metabolome of the immune tomato plants could lead to the development of new resistance inducers against Fusarium wilt treatment.


Assuntos
Fusarium , Doenças das Plantas , Imunidade Vegetal , Proteínas de Plantas , Transdução de Sinais/imunologia , Fusarium/imunologia , Fusarium/metabolismo , Solanum lycopersicum/imunologia , Solanum lycopersicum/metabolismo , Solanum lycopersicum/microbiologia , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/imunologia , Proteínas de Plantas/metabolismo
10.
Biomolecules ; 11(2)2021 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-33672873

RESUMO

Polysaccharides from marine algae are one novel source of plant defense elicitors for alternative and eco-friendly plant protection against phytopathogens. The effect of exopolysaccharides (EPS) produced by Porphyridium sordidum on elicitation of Arabidopsis thaliana defense responses against Fusarium oxysporum was evaluated. Firstly, in order to enhance EPS production, a Box-Behnken experimental design was carried out to optimize NaCl, NaNO3 and MgSO4 concentrations in the culture medium of microalgae. A maximum EPS production (2.45 g/L) higher than that of the control (0.7 g/L) was observed for 41.62 g/L NaCl, 0.63 g/L NaNO3 and 7.2 g/L MgSO4 concentrations. Structurally, the EPS contained mainly galactose, xylose and glucose. Secondly, the elicitor effect of EPS was evaluated by investigating the plant defense-related signaling pathways that include activation of Salicylic or Jasmonic Acid-dependent pathway genes. A solution of 2 mg/mL of EPS has led to the control of fungal growth by the plant. Results showed that EPS foliar application induced phenylalaline ammonia lyase and H2O2 accumulation. Expression profile analysis of the defense-related genes using qRT-PCR revealed the up-regulation of Superoxide dismutases (SOD), Peroxidase (POD), Pathogenesis-related protein 1 (PR-1) and Cytochrome P450 monooxyge-nase (CYP), while Catalase (CAT) and Plant defensin 1.2 (PDF1.2) were not induced. Results suggest that EPS may induce the elicitation of A. thaliana's defense response against F. oxysporum, activating the Salicylic Acid pathway.


Assuntos
Arabidopsis/efeitos dos fármacos , Fusarium/imunologia , Polissacarídeos/biossíntese , Porphyridium/metabolismo , Arabidopsis/imunologia , Arabidopsis/microbiologia , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia por Troca Iônica/métodos , DNA Ribossômico/genética , Interações Hospedeiro-Patógeno , Peróxido de Hidrogênio/metabolismo , Polissacarídeos/farmacologia , Porphyridium/classificação , Porphyridium/genética , RNA Ribossômico 18S/genética
11.
Nat Commun ; 12(1): 705, 2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33514716

RESUMO

Plant genomes encode hundreds of receptor kinases and peptides, but the number of known plant receptor-ligand pairs is limited. We report that the Arabidopsis leucine-rich repeat receptor kinase LRR-RK MALE DISCOVERER 1-INTERACTING RECEPTOR LIKE KINASE 2 (MIK2) is the receptor for the SERINE RICH ENDOGENOUS PEPTIDE (SCOOP) phytocytokines. MIK2 is necessary and sufficient for immune responses triggered by multiple SCOOP peptides, suggesting that MIK2 is the receptor for this divergent family of peptides. Accordingly, the SCOOP12 peptide directly binds MIK2 and triggers complex formation between MIK2 and the BRASSINOSTEROID INSENSITIVE 1-ASSOCIATED KINASE 1 (BAK1) co-receptor. MIK2 is required for resistance to the important root pathogen Fusarium oxysporum. Notably, we reveal that Fusarium proteomes encode SCOOP-like sequences, and corresponding synthetic peptides induce MIK2-dependent immune responses. These results suggest that MIK2 may recognise Fusarium-derived SCOOP-like sequences to induce immunity against Fusarium. The definition of SCOOPs as MIK2 ligands will help to unravel the multiple roles played by MIK2 during plant growth, development and stress responses.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/imunologia , Proteínas Fúngicas/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Doenças das Plantas/imunologia , Proteínas Quinases/metabolismo , Receptores de Superfície Celular/metabolismo , Arabidopsis/metabolismo , Arabidopsis/microbiologia , Proteínas de Arabidopsis/imunologia , Clonagem Molecular , Resistência à Doença/imunologia , Proteínas Fúngicas/imunologia , Fusarium/imunologia , Fusarium/metabolismo , Fusarium/patogenicidade , Peptídeos e Proteínas de Sinalização Intercelular/imunologia , Ligantes , Doenças das Plantas/microbiologia , Raízes de Plantas/imunologia , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Plantas Geneticamente Modificadas , Proteínas Quinases/imunologia , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Superfície Celular/imunologia , Transdução de Sinais/imunologia , /imunologia
12.
Mol Plant Pathol ; 22(2): 204-215, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33205901

RESUMO

Fusarium oxysporum (Fo) is best known as a host-specific vascular pathogen causing major crop losses. Most Fo strains, however, are root endophytes potentially conferring endophyte-mediated resistance (EMR). EMR is a mechanistically poorly understood root-specific induced resistance response induced by endophytic or nonhost pathogenic Fo strains. Like other types of induced immunity, such as systemic acquired resistance or induced systemic resistance, EMR has been proposed to rely on the activation of the pattern-triggered immunity (PTI) system of the plant. PTI is activated upon recognition of conserved microbe-associated molecular patterns (MAMPs) of invading microbes. Here, we investigated the role of PTI in controlling host colonization by Fo endophytes and their ability to induce EMR to the tomato pathogen Fo f. sp. lycopersici (Fol). Transgenic tomato and Arabidopsis plants expressing the Fo effector gene Avr2 are hypersusceptible to bacterial and fungal infection. Here we show that these plants are PTI-compromised and are nonresponsive to bacterial- (flg22) and fungal- (chitosan) MAMPs. We challenged the PTI-compromised tomato mutants with the EMR-conferring Fo endophyte Fo47, the nonhost pathogen Fom (a melon pathogen), and with Fol. Compared to wild-type plants, Avr2-tomato plants became hypercolonized by Fo47 and Fom. Surprisingly, however, EMR towards Fol, induced by either Fo47 or Fom, was unaffected in these plants. These data show that EMR-based disease resistance is independent from the conventional defence pathways triggered by PTI, but that PTI is involved in restricting host colonization by nonpathogenic Fo isolates.


Assuntos
Endófitos/imunologia , Fusarium/imunologia , Solanum lycopersicum/imunologia , Solanum lycopersicum/microbiologia , Arabidopsis/imunologia , Arabidopsis/microbiologia , Resistência à Doença/imunologia , Interações Hospedeiro-Patógeno , Doenças das Plantas/microbiologia
13.
Gene ; 764: 145078, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-32858175

RESUMO

In maize, eat rot and stalk rot caused by Fusarium verticillioides and Fusarium graminearum lead to contamination of moldy grains to produce mycotoxins. Identification of resistance genes against these pathogens for maize breeding is an effective way for disease control. Several 2-oxoglutarate-dependent dioxygenase (2OGD) proteins have been found to confer resistance to different pathogens in diverse plant species. However, little is known about the 2OGD superfamily in maize. Here, we identified 103 putative 2OGD genes in maize from a genome-wide analysis, and divided them into three classes - DOXA, DOXB, and DOXC. We further comprehensively investigated their gene structure, chromosome distribution, phylogenetic tree, gene-function enrichment, and expression profiles among different tissues. The genes encoding three 2OGD proteins, ACO, F3H, and NCS involved in ethylene biosynthesis, flavonoids biosynthesis, and alkaloids biosynthesis pathways, respectively, were identified to be induced by F. verticillioides and F. graminearum. The promoters of the three genes contain the binding sites for the transcription factor ZmDOF and ZmHSF, which are also induced by the two pathogens. The results imply that the three 2OGDs and the two transcription factors might be involved in the resistance to the two pathogens. This study provided a comprehensive understanding of the 2OGD superfamily in maize and laid the foundation for the further functional analysis of their roles in maize resistance to eat rot and stalk rot.


Assuntos
Dioxigenases/genética , Fusarium/imunologia , Proteínas de Plantas/genética , Zea mays/fisiologia , Sequência de Bases/genética , Sítios de Ligação/genética , Cromossomos de Plantas/genética , Coenzimas/metabolismo , Sequência Conservada/genética , Dioxigenases/imunologia , Dioxigenases/metabolismo , Resistência à Doença/genética , Evolução Molecular , Fusarium/patogenicidade , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas/fisiologia , Estudo de Associação Genômica Ampla , Ácidos Cetoglutáricos/metabolismo , Filogenia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/imunologia , Proteínas de Plantas/metabolismo , Caules de Planta/enzimologia , Caules de Planta/crescimento & desenvolvimento , Caules de Planta/microbiologia , Regiões Promotoras Genéticas/genética , RNA-Seq , Fatores de Transcrição/metabolismo , Zea mays/microbiologia
14.
Nat Commun ; 11(1): 4382, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32873802

RESUMO

Fusarium graminearum is a causal agent of Fusarium head blight (FHB) and a deoxynivalenol (DON) producer. In this study, OSP24 is identified as an important virulence factor in systematic characterization of the 50 orphan secreted protein (OSP) genes of F. graminearum. Although dispensable for growth and initial penetration, OSP24 is important for infectious growth in wheat rachis tissues. OSP24 is specifically expressed during pathogenesis and its transient expression suppresses BAX- or INF1-induced cell death. Osp24 is translocated into plant cells and two of its 8 cysteine-residues are required for its function. Wheat SNF1-related kinase TaSnRK1α is identified as an Osp24-interacting protein and shows to be important for FHB resistance in TaSnRK1α-overexpressing or silencing transgenic plants. Osp24 accelerates the degradation of TaSnRK1α by facilitating its association with the ubiquitin-26S proteasome. Interestingly, TaSnRK1α also interacts with TaFROG, an orphan wheat protein induced by DON. TaFROG competes against Osp24 for binding with the same region of TaSnRKα and protects it from degradation. Overexpression of TaFROG stabilizes TaSnRK1α and increases FHB resistance. Taken together, Osp24 functions as a cytoplasmic effector by competing against TaFROG for binding with TaSnRK1α, demonstrating the counteracting roles of orphan proteins of both host and fungal pathogens during their interactions.


Assuntos
Proteínas Fúngicas/metabolismo , Fusarium/patogenicidade , Doenças das Plantas/imunologia , Proteínas de Plantas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Triticum/microbiologia , Fatores de Virulência/metabolismo , Resistência à Doença , Fusarium/imunologia , Fusarium/metabolismo , Interações Hospedeiro-Patógeno/imunologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/imunologia , Plantas Geneticamente Modificadas , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/imunologia , Proteólise , Tricotecenos/metabolismo , Triticum/imunologia
15.
PLoS One ; 15(6): e0235482, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32603342

RESUMO

Fusarium head blight (FHB) is one of the most devastating fungal diseases affecting grain crops and Fusarium graminearum is the most aggressive causal species. Several evidences shown that stomatal closure is involved in the first line of defence against plant pathogens. However, there is very little evidence to show that photosynthetic parameters change in inoculated plants. The aim of the present study was to study the role of stomatal regulation in wheat after F. graminearum inoculation and explore its possible involvement in FHB resistance. RT-qPCR revealed that genes involved in stomatal regulation are induced in the resistant Sumai3 cultivar but not in the susceptible Rebelde cultivar. Seven genes involved in the positive regulation of stomatal closure were up-regulated in Sumai3, but it is most likely, that two genes, TaBG and TaCYP450, involved in the negative regulation of stomatal closure, were strongly induced, suggesting that FHB response is linked to cross-talk between the genes promoting and inhibiting stomatal closure. Increasing temperature of spikes in the wheat genotypes and a decrease in photosynthetic efficiency in Rebelde but not in Sumai3, were observed, confirming the hypothesis that photosynthetic parameters are related to FHB resistance.


Assuntos
Resistência à Doença/genética , Fusariose/imunologia , Fotossíntese , Estômatos de Plantas , Triticum/imunologia , Fusarium/imunologia , Fusarium/patogenicidade , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Fotossíntese/genética , Fotossíntese/imunologia , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Imunidade Vegetal/genética , Estômatos de Plantas/genética , Estômatos de Plantas/imunologia , Estômatos de Plantas/fisiologia , Triticum/genética , Triticum/microbiologia
16.
PLoS One ; 15(2): e0224413, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32045412

RESUMO

A facultative parasite of cereals, Fusarium culmorum is a soil-, air- and seed-borne fungus causing foot and root rot, fusarium seedling blight, and especially Fusarium head blight, a spike disease leading to decreased yield and mycotoxin contamination of grain. In the present study, we tested changes in expression of wheat genes (B2H2, ICS, PAL, and PR2) involved in defence against diseases. We first compared expression of the analysed genes in seedlings of non-inoculated and artificially inoculated wheat (variety Bohemia). The second part of the experiment compared expression of these genes in seedlings grown under various treatment conditions. These treatments were chosen to determine the effects of prochloraz, sodium bicarbonate, ergosterol, aescin and potassium iodide on expression of the analysed defence genes. In addition to the inoculated and non-inoculated cultivar Bohemia, we additionally examined two other varieties of wheat with contrasting resistance to Fusarium sp. infection. These were the blue aleurone layer variety Scorpion that is susceptible to Fusarium sp. infection and variety V2-49-17 with yellow endosperm and partial resistance to Fusarium sp. infection. In this manner, we were able to compare potential effects of inductors upon defence gene expression among three varieties with different susceptibility to infection but also between inoculated and non-inoculated seedlings of a single variety. The lowest infection levels were detected in the sodium bicarbonate treatment. Sodium bicarbonate had not only negative influence on Fusarium growth but also positively affected expression of plant defence genes. Expression of the four marker genes shown to be important in plant defence was significantly affected by the treatments. The greatest upregulation in comparison to the water control was identified under all treatments for the B2H2 gene. Only expression of PAL under the ergosterol and prochloraz treatments were not statistically significant.


Assuntos
Fusarium/imunologia , Perfilação da Expressão Gênica , Doenças das Plantas/microbiologia , Plântula/microbiologia , Triticum/genética , Resistência à Doença/genética , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Plântula/genética , Bicarbonato de Sódio/farmacologia
17.
Front Immunol ; 11: 9, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32038657

RESUMO

Fungal infections, widespread throughout the world, affect a broad range of life forms, including agriculturally relevant plants, humans, and insects. In defending against fungal infections, the fruit fly Drosophila melanogaster employs the Toll pathway to induce a large number of immune peptides. Some have been investigated, such as the antimicrobial peptides (AMPs) and Bomanins (Boms); many, however, remain uncharacterized. Here, we examine the role in innate immunity of two related peptides, Daisho1 and Daisho2 (formerly IM4 and IM14, respectively), found in hemolymph following Toll pathway activation. By generating a CRISPR/Cas9 knockout of both genes, Δdaisho, we find that the Daisho peptides are required for defense against a subset of filamentous fungi, including Fusarium oxysporum, but not other Toll-inducible pathogens, such as Enterococcus faecalis and Candida glabrata. Analysis of null alleles and transgenes revealed that the two daisho genes are each required for defense, although their functions partially overlap. Generating and assaying a genomic epitope-tagged Daisho2 construct, we detected interaction in vitro of Daisho2 peptide in hemolymph with the hyphae of F. oxysporum. Together, these results identify the Daisho peptides as a new class of innate immune effectors with humoral activity against a select set of filamentous fungi.


Assuntos
Peptídeos Catiônicos Antimicrobianos/metabolismo , Candida glabrata/imunologia , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/imunologia , Drosophila melanogaster/microbiologia , Enterococcus faecalis/imunologia , Fusarium/imunologia , Animais , Animais Geneticamente Modificados , Peptídeos Catiônicos Antimicrobianos/genética , Sistemas CRISPR-Cas , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Técnicas de Inativação de Genes , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Hifas/imunologia , Imunidade Inata , Transdução de Sinais/genética , Transdução de Sinais/imunologia
18.
Int J Environ Health Res ; 30(5): 545-557, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31044611

RESUMO

Airborne fungal spores are extensively reported as the elicitors of respiratory allergies in human. Fusarium lateritium is one such fungal species reported for eliciting significant skin prick results from India. The present study aims to analyze the allergenic potential of F. lateritium followed by the identification of allergens. The total protein of F. lateritium was subjected to 1dimensional (1D) and 2D gel electrophoresis followed by corresponding IgE-specific immunoblots. We found 8 immunoreactive bands/zones in (1D) immunoblot using 11 F. lateritium-sensitised patient sera. In 1D immunoblot, a 34 kDa band was detected in >80% of the patients and hence considered as a potential allergen of F. lateritium. Corresponding 34 kDa spot in 2D-immunoblot was analyzed by mass spectrometric analysis and identified as Glyceraldehyde 3-phosphate dehydrogenase. The identified F. lateritium allergen holds the potential to instigate vaccine development for immunotherapy of F. lateritium sensitized patients.


Assuntos
Alérgenos/imunologia , Proteínas Fúngicas/imunologia , Fusarium/química , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fusarium/imunologia , Humanos , Immunoblotting , Índia , Masculino , Pessoa de Meia-Idade , Proteômica , Adulto Jovem
19.
Artigo em Inglês | MEDLINE | ID: mdl-31818813

RESUMO

There are limited treatment options for immunosuppressed patients with lethal invasive fungal infections due to Fusarium and Scedosporium Manogepix (MGX; APX001A) is a novel antifungal that targets the conserved Gwt1 enzyme required for localization of glycosylphosphatidylinositol-anchored mannoproteins in fungi. We evaluated the in vitro activity of MGX and the efficacy of the prodrug fosmanogepix (APX001) in immunosuppressed murine models of hematogenously disseminated fusariosis and pulmonary scedosporiosis. The MGX minimum effective concentration (MEC) for Scedosporium isolates was 0.03 µg/ml and ranged from 0.015 to 0.03 µg/ml for Fusarium isolates. In the scedosporiosis model, treatment of mice with 78 mg/kg and 104 mg/kg of body weight fosmanogepix, along with 1-aminobenzotriazole (ABT) to enhance the serum half-life of MGX, significantly increased median survival time versus placebo from 7 days to 13 and 11 days, respectively. Furthermore, administration of 104 mg/kg fosmanogepix resulted in an ∼2-log10 reduction in lung, kidney, or brain conidial equivalents/gram tissue (CE). Similarly, in the fusariosis model, 78 mg/kg and 104 mg/kg fosmanogepix plus ABT enhanced median survival time from 7 days to 12 and 10 days, respectively. A 2- to 3-log10 reduction in kidney and brain CE was observed. In both models, reduction in tissue fungal burden was corroborated with histopathological data, with target organs showing reduced or no abscesses in fosmanogepix-treated mice. Survival and tissue clearance were comparable to a clinically relevant high dose of liposomal amphotericin B (10 to 15 mg/kg). Our data support the continued development of fosmanogepix as a first-in-class treatment for infections caused by these rare molds.


Assuntos
Aminopiridinas/farmacologia , Antifúngicos/farmacologia , Fusariose/tratamento farmacológico , Fusarium/efeitos dos fármacos , Hospedeiro Imunocomprometido , Infecções Fúngicas Invasivas/tratamento farmacológico , Isoxazóis/farmacologia , Scedosporium/efeitos dos fármacos , Aminopiridinas/sangue , Aminopiridinas/farmacocinética , Animais , Antifúngicos/sangue , Antifúngicos/farmacocinética , Disponibilidade Biológica , Encéfalo/efeitos dos fármacos , Encéfalo/imunologia , Encéfalo/microbiologia , Esquema de Medicação , Combinação de Medicamentos , Fusariose/imunologia , Fusariose/microbiologia , Fusariose/mortalidade , Fusarium/crescimento & desenvolvimento , Fusarium/imunologia , Meia-Vida , Humanos , Infecções Fúngicas Invasivas/imunologia , Infecções Fúngicas Invasivas/microbiologia , Infecções Fúngicas Invasivas/mortalidade , Isoxazóis/sangue , Isoxazóis/farmacocinética , Rim/efeitos dos fármacos , Rim/imunologia , Rim/microbiologia , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Testes de Sensibilidade Microbiana , Pró-Fármacos , Scedosporium/crescimento & desenvolvimento , Scedosporium/imunologia , Análise de Sobrevida , Triazóis/farmacologia
20.
J Dermatol ; 47(2): 181-184, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31829468

RESUMO

Fusariosis is the second most common mold infection after aspergillosis, and keratomycosis is the most encountered implantation infection. Here, we report a case of a 4-year-old Han Chinese girl presenting with an itchy mass on her right face of almost 2 years' duration. Direct smear of the lesion sample was positive for fungal hyphae. Biopsy of the lesion showed many fungal hyphae in the epidermis and dermis. The pathogen was identified as Fusarium lichenicola by molecular sequencing and phylogenetic analysis based on the TEF-1α gene. Whole-exome sequencing analysis using her peripheral blood revealed a heterozygous mutation in the STAT3 gene, which is related to autosomal dominant hyper-immunoglobulin E syndrome (AD-HIES). The lesion improved following treatment with i.v. and intralesional amphotericin B, oral voriconazole and topical luliconazole cream. To our knowledge, this is the second reported case of a special localized cutaneous lesion caused by Fusarium species in a child with AD-HIES. Both cases suggest that STAT3 deficiency may increase susceptibility to fusariosis.


Assuntos
Antifúngicos/administração & dosagem , Fusariose/diagnóstico , Fusarium/isolamento & purificação , Síndrome de Job/imunologia , Administração Cutânea , Administração Oral , Anfotericina B/administração & dosagem , Biópsia , Pré-Escolar , Análise Mutacional de DNA , Quimioterapia Combinada/métodos , Face , Feminino , Fusariose/imunologia , Fusariose/microbiologia , Fusarium/imunologia , Humanos , Imidazóis/administração & dosagem , Injeções Intralesionais , Síndrome de Job/complicações , Síndrome de Job/diagnóstico , Síndrome de Job/genética , Fator de Transcrição STAT3/genética , Pele/microbiologia , Resultado do Tratamento , Voriconazol/administração & dosagem , Sequenciamento do Exoma
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...