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1.
Nat Commun ; 12(1): 5494, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34535661

RESUMO

Sessile plants encode a large number of small peptides and cell surface-resident receptor kinases, most of which have unknown functions. Here, we report that the Arabidopsis receptor kinase MALE DISCOVERER 1-INTERACTING RECEPTOR-LIKE KINASE 2 (MIK2) recognizes the conserved signature motif of SERINE-RICH ENDOGENOUS PEPTIDEs (SCOOPs) from Brassicaceae plants as well as proteins present in fungal Fusarium spp. and bacterial Comamonadaceae, and elicits various immune responses. SCOOP signature peptides trigger immune responses and altered root development in a MIK2-dependent manner with a sub-nanomolar sensitivity. SCOOP12 directly binds to the extracellular leucine-rich repeat domain of MIK2 in vivo and in vitro, indicating that MIK2 is the receptor of SCOOP peptides. Perception of SCOOP peptides induces the association of MIK2 and the coreceptors SOMATIC EMBRYOGENESIS RECEPTOR KINASE 3 (SERK3) and SERK4 and relays the signaling through the cytosolic receptor-like kinases BOTRYTIS-INDUCED KINASE 1 (BIK1) and AVRPPHB SUSCEPTIBLE1 (PBS1)-LIKE 1 (PBL1). Our study identifies a plant receptor that bears a dual role in sensing the conserved peptide motif from phytocytokines and microbial proteins via a convergent signaling relay to ensure a robust immune response.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/imunologia , Arabidopsis/microbiologia , Citocinas/metabolismo , Fusarium/fisiologia , Imunidade Vegetal , Proteínas Quinases/metabolismo , Receptores de Superfície Celular/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Proteínas de Arabidopsis/química , Mutação/genética , Peptídeos/química , Peptídeos/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Domínios Proteicos , Proteínas Quinases/química , Receptores de Superfície Celular/química
2.
Ann Agric Environ Med ; 28(3): 409-413, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34558262

RESUMO

INTRODUCTION AND OBJECTIVES: With the rising number of contact lens users, there has been observed an increasing number of patients admitted to ophthalmology wards with severe keratitis, including those of fungal etiology. One of the most devastating specimens is Fusarium spp. If not diagnosed and treated from the onset of the symptoms, it can lead to severe visual loss, or even blindness. CASE REPORT: This a retrospective case report of a 36-year-old pregnant female diagnosed with Fusarium keratitis, not responding to topical treatment. The problem is discussed and includes the most relevant literature review. RESULTS: Primary therapeutic keratoplasty is prone to failure due to an ongoing inflammation process in the eye, as happened in the described patient. Spread of the infection to the vitreous body necessitated the procedure of penetrating keratoplasty with lens removal, pars plana vitrectomy and silicone oil. After treatment, the inflammation resolved, and best corrected visual acuity at the 6 months follow-up was 0.5 (Snellen charts). CONCLUSIONS: There is currently no treatment for Fusarium keratitis that would offer similar results to those observed in bacterial infection treated early with antibiotics. As systemic therapy with antifungal agents is not an option in pregnant women, they are even more of a challenge. Diagnosis is quite often delayed, leading to deeper infiltration of the cornea, sometimes with vitreous involvement. For such cases, a combined approach is proposed with vitrectomy, lens removal and penetrating keratoplasty. Early surgical intervention may rescue some of the eyes non-responsive to topical and systemic treatment.


Assuntos
Infecções Oculares Fúngicas/microbiologia , Ceratite/microbiologia , Transplante de Córnea , Infecções Oculares Fúngicas/cirurgia , Feminino , Fusarium/fisiologia , Humanos , Ceratite/cirurgia , Gravidez , Estudos Retrospectivos , Vitrectomia
3.
Fungal Biol ; 125(9): 725-732, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34420699

RESUMO

Filamentous fungi grow by the elaboration of hyphae, which may fuse to form a network as a colony develops. Fusion of hyphae can occur between genetically different individuals, provided they share a common allele at loci affecting somatic compatibility. Diversity in somatic compatibility phenotypes reduces the frequency of hyphal fusion in a population, thereby slowing the spread of deleterious genetic elements such as viruses and plasmids, which require direct cytoplasmic contact for transmission. Diverse somatic compatibility phenotypes can be generated by recombining alleles through sexual reproduction, but this mechanism may not fully account for the diversity found in nature. For example, multiple compatibility phenotypes of Fusarium circinatum were shown to be associated with the same clonal lineage, which implies they were derived by a mutation rather than recombination through sexual reproduction. Experimental tests of this hypothesis confirmed that spontaneous changes in somatic compatibility can occur at a frequency between 5 and 8 per million spores. Genomic analysis of F. circinatum strains with altered somatic compatibility revealed no consistent evidence of recombination and supported the hypothesis that a spontaneous mutation generated the observed phenotypic change. Genes known to be involved in somatic compatibility had no mutations, suggesting that mutation occurred in a gene with an as yet unexplored function in somatic compatibility.


Assuntos
Fusarium , Hifas , Fusarium/fisiologia , Genes Fúngicos/genética , Humanos , Hifas/genética , Mutação , Esporos Fúngicos/genética
4.
PLoS One ; 16(8): e0252365, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34351929

RESUMO

In filamentous fungi, gene silencing by RNA interference (RNAi) shapes many biological processes, including pathogenicity. Recently, fungal small RNAs (sRNAs) have been shown to act as effectors that disrupt gene activity in interacting plant hosts, thereby undermining their defence responses. We show here that the devastating mycotoxin-producing ascomycete Fusarium graminearum (Fg) utilizes DICER-like (DCL)-dependent sRNAs to target defence genes in two Poaceae hosts, barley (Hordeum vulgare, Hv) and Brachypodium distachyon (Bd). We identified 104 Fg-sRNAs with sequence homology to host genes that were repressed during interactions of Fg and Hv, while they accumulated in plants infected by the DCL double knock-out (dKO) mutant PH1-dcl1/2. The strength of target gene expression correlated with the abundance of the corresponding Fg-sRNA. Specifically, the abundance of three tRNA-derived fragments (tRFs) targeting immunity-related Ethylene overproducer 1-like 1 (HvEOL1) and three Poaceae orthologues of Arabidopsis thaliana BRI1-associated receptor kinase 1 (HvBAK1, HvSERK2 and BdSERK2) was dependent on fungal DCL. Additionally, RNA-ligase-mediated Rapid Amplification of cDNA Ends (RLM-RACE) identified infection-specific degradation products for the three barley gene transcripts, consistent with the possibility that tRFs contribute to fungal virulence via targeted gene silencing.


Assuntos
Brachypodium , Fusarium/fisiologia , Hordeum , Interações Hospedeiro-Patógeno , Doenças das Plantas/microbiologia , RNA Fúngico/metabolismo , Ribonuclease III/metabolismo , Fatores de Virulência/metabolismo , Brachypodium/metabolismo , Brachypodium/microbiologia , Proteínas Fúngicas , Hordeum/metabolismo , Hordeum/microbiologia , Doenças das Plantas/genética , RNA Fúngico/genética , Ribonuclease III/genética , Fatores de Virulência/genética
5.
Appl Environ Microbiol ; 87(20): e0096721, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34378994

RESUMO

The plant pathogen Fusarium graminearum contains two α-tubulin isotypes (α1 and α2) and two ß-tubulin isotypes (ß1 and ß2). The functional roles of these tubulins in microtubule assembly are not clear. Previous studies reported that α1- and ß2-tubulin deletion mutants showed severe growth defects and hypersensitivity to carbendazim, which have not been well explained. Here, we investigated the interaction between α- and ß-tubulin of F. graminearum. Colocalization experiments demonstrated that ß1- and ß2-tubulin are colocalized. Coimmunoprecipitation experiments suggested that ß1-tubulin binds to both α1- and α2-tubulin and that ß2-tubulin can also bind to α1- or α2-tubulin. Interestingly, deletion of α1-tubulin increased the interaction between ß2-tubulin and α2-tubulin. Microtubule observation assays showed that deletion of α1-tubulin completely disrupted ß1-tubulin-containing microtubules and significantly decreased ß2-tubulin-containing microtubules. Deletion of α2-, ß1-, or ß2-tubulin had no obvious effect on the microtubule cytoskeleton. However, microtubules in α1- and ß2-tubulin deletion mutants were easily depolymerized in the presence of carbendazim. The sexual reproduction assay indicates that α1- and ß1-tubulin deletion mutants could not produce asci and ascospores. These results implied that α1-tubulin may be essential for the microtubule cytoskeleton. However, our Δα1-2×α2 mutant (α1-tubulin deletion mutant containing two copies of α2-tubulin) exhibited normal microtubule network, growth, and sexual reproduction. Interestingly, the Δα1-2×α2 mutant was still hypersensitive to carbendazim. In addition, both ß1-tubulin and ß2-tubulin were found to bind the mitochondrial outer membrane voltage-dependent anion channel (VDAC), indicating that they could regulate the function of VDAC. IMPORTANCE In this study, we found that F. graminearum contains four different α-/ß-tubulin heterodimers (α1-/ß1-, α1-/ß2-, α2-/ß1-, and α2-/ß2-tubulin heterodimers), and they assemble together into a single microtubule. Moreover, α1- and α2-tubulins are functionally interchangeable in microtubule assembly, vegetative growth, and sexual reproduction. These results provide more insights into the functional roles of different tubulins of F. graminearum, which could be helpful for purification of tubulin heterodimers and development of new tubulin-binding agents.


Assuntos
Fusarium/fisiologia , Microtúbulos/fisiologia , Tubulina (Proteína)/fisiologia , Proteínas Fúngicas/fisiologia , Fusarium/genética , Fusarium/crescimento & desenvolvimento , Canais de Ânion Dependentes de Voltagem/fisiologia
6.
Int J Mol Sci ; 22(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206508

RESUMO

Plants of the genus Allium developed a diversity of defense mechanisms against pathogenic fungi of the genus Fusarium, including transcriptional activation of pathogenesis-related (PR) genes. However, the information on the regulation of PR factors in garlic (Allium sativum L.) is limited. In the present study, we identified AsPR genes putatively encoding PR1, PR2, PR4, and PR5 proteins in A. sativum cv. Ershuizao, which may be involved in the defense against Fusarium infection. The promoters of the AsPR1-5 genes contained jasmonic acid-, salicylic acid-, gibberellin-, abscisic acid-, auxin-, ethylene-, and stress-responsive elements associated with the response to plant parasites. The expression of AsPR1c, d, g, k, AsPR2b, AsPR5a, c (in roots), and AsPR4a(c), b, and AsPR2c (in stems and cloves) significantly differed between garlic cultivars resistant and susceptible to Fusarium rot, suggesting that it could define the PR protein-mediated protection against Fusarium infection in garlic. Our results provide insights into the role of PR factors in A. sativum and may be useful for breeding programs to increase the resistance of Allium crops to Fusarium infections.


Assuntos
Fusarium , Alho/genética , Alho/microbiologia , Genes de Plantas , Interações Hospedeiro-Patógeno/genética , Família Multigênica , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Clonagem Molecular , Fusarium/fisiologia , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Genômica/métodos , Regiões Promotoras Genéticas
7.
Int J Mol Sci ; 22(14)2021 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-34299055

RESUMO

Fusarium culmorum is a worldwide, soil-borne plant pathogen. It causes diseases of cereals, reduces their yield, and fills the grain with toxins. The main direction of modern breeding is to select wheat genotypes the most resistant to Fusarium diseases. This study uses seedlings and plants at the anthesis stage to analyze total soluble carbohydrates, total and cell-wall bound phenolics, chlorophyll content, antioxidant activity, hydrogen peroxide content, mycotoxin accumulation, visual symptoms of the disease, and Fusarium head blight index (FHBi). These results determine the resistance of three durum wheat accessions. We identify physiological or biochemical markers of durum wheat resistance to F. culmorum. Our results confirm correlations between FHBi and mycotoxin accumulation in the grain, which results in grain yield decrease. The degree of spike infection (FHBi) may indicate accumulation mainly of deoxynivalenol and nivalenol in the grain. High catalase activity in the infected leaves could be considered a biochemical marker of durum sensitivity to this fungus. These findings allowed us to formulate a strategy for rapid evaluation of the disease severity and the selection of plants with higher level, or resistance to F. culmorum infection.


Assuntos
Biomarcadores/metabolismo , Fusarium/fisiologia , Doenças das Plantas/microbiologia , Plântula/fisiologia , Tricotecenos/metabolismo , Triticum/fisiologia , Genótipo , Plântula/microbiologia , Triticum/classificação , Triticum/genética , Triticum/microbiologia
8.
Int J Mol Sci ; 22(12)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34204013

RESUMO

Plant immunity is mediated in large part by specific interactions between a host resistance protein and a pathogen effector protein, named effector-triggered immunity (ETI). ETI needs to be tightly controlled both positively and negatively to enable normal plant growth because constitutively activated defense responses are detrimental to the host. In previous work, we reported that mutations in SUPPRESSOR OF rps4-RLD1 (SRFR1), identified in a suppressor screen, reactivated EDS1-dependent ETI to Pseudomonas syringae pv. tomato (Pto) DC3000. Besides, mutations in SRFR1 boosted defense responses to the generalist chewing insect Spodoptera exigua and the sugar beet cyst nematode Heterodera schachtii. Here, we show that mutations in SRFR1 enhance susceptibility to the fungal necrotrophs Fusarium oxysporum f. sp. lycopersici (FOL) and Botrytis cinerea in Arabidopsis. To translate knowledge obtained in AtSRFR1 research to crops, we generated SlSRFR1 alleles in tomato using a CRISPR/Cas9 system. Interestingly, slsrfr1 mutants increased expression of SA-pathway defense genes and enhanced resistance to Pto DC3000. In contrast, slsrfr1 mutants elevated susceptibility to FOL. Together, these data suggest that SRFR1 is functionally conserved in both Arabidopsis and tomato and functions antagonistically as a negative regulator to (hemi-) biotrophic pathogens and a positive regulator to necrotrophic pathogens.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/imunologia , Arabidopsis/microbiologia , Botrytis/fisiologia , Resistência à Doença/imunologia , Fusarium/fisiologia , Imunidade Vegetal , Alelos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Sequência de Bases , Sistemas CRISPR-Cas/genética , Resistência à Doença/genética , Edição de Genes , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Vetores Genéticos/metabolismo , Lycopersicon esculentum/genética , Mutação/genética , Imunidade Vegetal/genética , Plasmídeos/genética
9.
BMC Plant Biol ; 21(1): 304, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34193039

RESUMO

BACKGROUND: The production of cereal crops is frequently affected by diseases caused by Fusarium graminearum and Magnaporthe oryzae, two devastating fungal pathogens. To improve crop resistance, many studies have focused on understanding the mechanisms of host defense against these two fungi individually. However, our knowledge of the common and different host defenses against these pathogens is very limited. RESULTS: In this study, we employed Brachypodium distachyon as a model for cereal crops and performed comparative transcriptomics to study the dynamics of host gene expression at different infection stages. We found that infection with either F. graminearum or M. oryzae triggered massive transcriptomic reprogramming in the diseased tissues. Numerous defense-related genes were induced with dynamic changes during the time course of infection, including genes that function in pattern detection, MAPK cascade, phytohormone signaling, transcription, protein degradation, and secondary metabolism. In particular, the expression of jasmonic acid signaling genes and proteasome component genes were likely specifically inhibited or manipulated upon infection by F. graminearum. CONCLUSIONS: Our analysis showed that, although the affected host pathways are similar, their expression programs and regulations are distinct during infection by F. graminearum and M. oryzae. The results provide valuable insight into the interactions between B. distachyon and two important cereal pathogens.


Assuntos
Ascomicetos/fisiologia , Brachypodium/genética , Brachypodium/microbiologia , Fusarium/fisiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Redes Reguladoras de Genes , Interações Hospedeiro-Patógeno/genética , Doenças das Plantas/microbiologia , Mapas de Interação de Proteínas/genética
10.
Int J Biol Macromol ; 182: 1883-1892, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34062161

RESUMO

Biocontrol of soil-borne pathogens by recruiting soil microbiota brings forth benefits to soil quality and plant production while lowers environmental impact. Succinoglycan possesses various biological activities, but its role in soil amendment is still elusive. The succinoglycan Riclin was investigated in this study as a polysaccharide-type biocontrol agent for improving the soil suppressiveness on a typical fungal pathogen Fusarium oxysporum f. sp. cucumerinum (FOC). Results demonstrated that addition of Riclin increased the soil microbial carbon and lowered the species richness of soil fungal communities. After addition of 2.5 mg/g Riclin for 90 days, the relative abundance of Actinobacteria and Firmicutes were increased by 76.6% and 193.4%, compared with the control. Meanwhile, Proteobacteria and Ascomycota were decreased by 25.9% and 30.4%. The relative abundance of beneficial genera, namely Nocardioides, Kribbella, Streptomyces, Gaiella, Marmoricola, Bacillus, and Rhizobium, became 1.13, 5.17, 0.87, 0.45, 3.57, 4.53, and 6.30 folds higher than the control, respectively. Antagonism towards soil-borne pathogens was probably enhanced as both hydrolase activity and biosynthesis of bioactive secondary compounds were improved. Importantly, Riclin-treated soil significantly reduced the incidence of Fusarium wilt of cucumber seedlings by suppression of FOC. In conclusion, addition of Riclin was conducive to the improvement of soil suppressiveness.


Assuntos
Cucumis sativus/microbiologia , Fusarium/fisiologia , Microbiota/efeitos dos fármacos , Doenças das Plantas/microbiologia , Polissacarídeos Bacterianos/farmacologia , Probióticos/farmacologia , Plântula/microbiologia , Microbiologia do Solo , Biodiversidade , Cucumis sativus/efeitos dos fármacos , Fusarium/efeitos dos fármacos , Microbiota/genética , Filogenia , Plântula/efeitos dos fármacos , Solo/química , Fatores de Tempo
11.
Commun Biol ; 4(1): 707, 2021 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-34108627

RESUMO

Many plant pathogenic fungi contain conditionally dispensable (CD) chromosomes that are associated with virulence, but not growth in vitro. Virulence-associated CD chromosomes carry genes encoding effectors and/or host-specific toxin biosynthesis enzymes that may contribute to determining host specificity. Fusarium oxysporum causes devastating diseases of more than 100 plant species. Among a large number of host-specific forms, F. oxysporum f. sp. conglutinans (Focn) can infect Brassicaceae plants including Arabidopsis (Arabidopsis thaliana) and cabbage. Here we show that Focn has multiple CD chromosomes. We identified specific CD chromosomes that are required for virulence on Arabidopsis, cabbage, or both, and describe a pair of effectors encoded on one of the CD chromosomes that is required for suppression of Arabidopsis-specific phytoalexin-based immunity. The effector pair is highly conserved in F. oxysporum isolates capable of infecting Arabidopsis, but not of other plants. This study provides insight into how host specificity of F. oxysporum may be determined by a pair of effector genes on a transmissible CD chromosome.


Assuntos
Cromossomos Fúngicos/genética , Fusarium/genética , Doenças das Plantas/microbiologia , Arabidopsis/imunologia , Arabidopsis/microbiologia , Brassicaceae/imunologia , Brassicaceae/microbiologia , Cromossomos Fúngicos/fisiologia , Fusarium/patogenicidade , Fusarium/fisiologia , Genoma Fúngico/genética , Interações Hospedeiro-Patógeno/imunologia , Doenças das Plantas/imunologia
12.
Theor Appl Genet ; 134(8): 2379-2398, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34128089

RESUMO

KEY MESSAGE: Methyl esterase (MES), PvMES1, contributes to the defense response toward Fusarium wilt in common beans by regulating the salicylic acid (SA) mediated signaling pathway from phenylpropanoid synthesis and sugar metabolism as well as others. Common bean (Phaseolus vulgaris L.) is an important food legume. Fusarium wilt caused by Fusarium oxysporum f. sp. phaseoli is one of the most serious soil-borne diseases of common bean found throughout the world and affects the yield and quality of the crop. Few sources of Fusarium wilt resistance exist in legumes and most are of quantitative inheritance. In this study, we have identified a methyl esterase (MES), PvMES1, that contributes to plant defense response by regulating the salicylic acid (SA) mediated signaling pathway in response to Fusarium wilt in common beans. The result showed the role of PvMES1 in regulating SA levels in common bean and thus the SA signaling pathway and defense response mechanism in the plant. Overexpression of the PvMES1 gene enhanced Fusarium wilt resistance; while silencing of the gene caused susceptibility to the diseases. RNA-seq analysis with these transiently modified plants showed that genes related to SA level changes included the following gene ontologies: (a) phenylpropanoid synthesis; (b) sugar metabolism; and (c) interaction between host and pathogen as well as others. These key signal elements activated the defense response pathway in common bean to Fusarium wilt. Collectively, our findings indicate that PvMES1 plays a pivotal role in regulating SA biosynthesis and signaling, and increasing Fusarium wilt resistance in common bean, thus providing novel insight into the practical applications of both SA and MES genes and pathways they contribute to for developing elite crop varieties with enhanced broad-spectrum resistance to this critical disease.


Assuntos
Resistência à Doença/imunologia , Fusarium/fisiologia , Oxirredutases O-Desmetilantes/metabolismo , Phaseolus/imunologia , Doenças das Plantas/imunologia , Proteínas de Plantas/metabolismo , Ácido Salicílico/metabolismo , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Oxirredutases O-Desmetilantes/genética , Phaseolus/genética , Phaseolus/crescimento & desenvolvimento , Phaseolus/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Transdução de Sinais
13.
Theor Appl Genet ; 134(9): 3037-3049, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34110431

RESUMO

KEY MESSAGE: Stably expressed type I and type II resistance QTL were identified using two Yangmai 158-derived RIL populations, and plant-height and flowering-time QTL intervals detected did not contribute to the FHB resistance variations. Yangmai 158 (Y158) is an elite wheat cultivar widely grown in China with stable Fusarium head blight (FHB) resistance. To enrich the genetic basis underlying FHB resistance, QTL mapping was conducted using two recombinant inbred line (RIL) populations derived from crosses of Y158 with susceptible lines Annong 8455 and Veery. Survey with makers linked to Fhb1, Fhb2, Fhb4 and Fhb5 in resistance cultivar Wangshuibai indicated that both Y158 and the susceptible lines do not contain these QTL. The RIL populations were surveyed with 65 PCR markers and 55 K chip, which generated 23,159 valid marker data, to produce genetic maps for whole genome scanning of quantitative trait loci (QTL). A total of six QTL, all with the Y158 alleles for better resistance and including one stably expressed QTL for type I resistance (Qfhi.nau-2D) and one stably expressed QTL for type II resistance (Qfhs.nau-2A), were identified. Moreover, taking advantage of the great genetic variations in plant height and flowering time, QTL conditioning these two traits were determined. Of six plant-height QTL and three flowering-time QTL intervals detected, none were associated with FHB resistance. The FHB resistance QTL in Y158 were shown to be useful alternatives in FHB resistance breeding programs. The SNP markers flanking Qfhs.nau-2A and Qfhi.nau-2D have been converted to breeder-friendly PCR-based markers to facilitate their applications.


Assuntos
Mapeamento Cromossômico/métodos , Cromossomos de Plantas/genética , Resistência à Doença/imunologia , Fusarium/fisiologia , Doenças das Plantas/imunologia , Proteínas de Plantas/metabolismo , Triticum/genética , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Triticum/crescimento & desenvolvimento , Triticum/microbiologia
14.
Sci Rep ; 11(1): 11327, 2021 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-34059713

RESUMO

Metarhizium robertsii is an insect pathogen as well as an endophyte, and can antagonize the phytopathogen, Fusarium solani during bean colonization. However, plant immune responses to endophytic colonization by Metarhizium are largely unknown. We applied comprehensive plant hormone analysis, transcriptional expression and stomatal size analysis in order to examine plant immune responses to colonization by Metarhizium and/or Fusarium. The total amount of abscisic acid (ABA) and ABA metabolites decreased significantly in bean leaves by plant roots colonized by M. robertsii and increased significantly with F. solani compared to the un-inoculated control bean plant. Concomitantly, in comparison to the un-inoculated bean, root colonization by Metarhizium resulted in increased stomatal size in leaves and reduced stomatal size with Fusarium. Meanwhile, expression of plant immunity genes was repressed by Metarhizium and, alternately, triggered by Fusarium compared to the un-inoculated plant. Furthermore, exogenous application of ABA resulted in reduction of bean root colonization by Metarhizium but increased colonization by Fusarium compared to the control without ABA application. Our study suggested that ABA plays a central role in differential responses to endophytic colonization by Metarhizium and pathogenic colonization by Fusarium and, we also observed concomitant differences in stomatal size and expression of plant immunity genes.


Assuntos
Ácido Abscísico/metabolismo , Fusarium/fisiologia , Interações Hospedeiro-Patógeno/imunologia , Metarhizium/fisiologia , Phaseolus/microbiologia , Endófitos/fisiologia , Regulação da Expressão Gênica de Plantas , Phaseolus/fisiologia , Imunidade Vegetal/genética , Estômatos de Plantas/fisiologia
15.
Food Chem ; 359: 129847, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33964656

RESUMO

Surface-enhanced Raman spectroscopy (SERS) and deep learning network were adopted to develop a detection method for deoxynivalenol (DON) residues in Fusarium head blight (FHB)-infected wheat kernels. First, the liquid-liquid interface self-extraction was conducted for the rapid separation of DON in samples. Then, the gold nanorods modified with sodium citrate (Cit-AuNRs) were prepared as substrate for a gigantic enhancement of SERS signal. Results showed that the spectral characteristic peaks for DON residues of 99.5-0.5 mg/L were discernible with the relative standard deviation of 4.2%, with the limit of detection of 0.11 mg/L. Meanwhile, the fully convolutional network for the spectra of matrix input form was developed and obtained the optimal quantitative performance, with a root-mean-square error of prediction of 4.41 mg/L and coefficient of determination of prediction of 0.9827. Thus, the proposed method provides a simple, sensitive, and intelligent detection for DON in FHB-infected wheat kernels.


Assuntos
Fusarium/fisiologia , Ouro/química , Nanotubos/química , Citrato de Sódio/química , Análise Espectral Raman/métodos , Tricotecenos/análise , Triticum/química , Extração Líquido-Líquido , Doenças das Plantas/microbiologia , Tricotecenos/isolamento & purificação , Triticum/microbiologia
16.
Exp Eye Res ; 207: 108581, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33865843

RESUMO

Fungal keratitis (FK) pathology is driven by both fungal growth and inflammation within the corneal stroma. Standard in vitro infection models ̶ involving co-culture of the pathogen and the corneal cells in tissue culture medium ̶ are sufficient to probe host responses to the fungus; however, they lack the physiological structure and nutrient composition of the stroma to accurately study fungal invasiveness and metabolic processes. We therefore sought to develop a culture model of FK that would allow for both host and fungal cell biology to be evaluated in parallel. Towards this end, we employed a previously described system in which primary human cornea fibroblasts (HCFs) are cultured on transwell membranes, whereupon they secrete a three-dimensional (3D) collagen matrix that resembles the human stroma. We demonstrated that two common mold agents of FK, Fusarium petroliphilum and Aspergillus fumigatus, penetrated into these constructs and caused a disruption of the collagen matrix that is characteristic of infection. HCF morphology appeared altered in the presence of fungus and electron microscopy revealed a clear internalization of fungal spores into these cells. Consistent with this apparent phagocyte-like activity of the HCFs, mRNA and protein levels for several pro-inflammatory cytokines/chemokines (including TNFα, IL-1ß, IL-6, and IL-8) were significantly upregulated compared to uninfected samples. We similarly found an upregulation of several HCF metalloproteases (MMPs), which are enzymes that breakdown collagen during wound healing and may further activate pro-inflammatory signaling molecules. Finally, several fungal collagenase genes were upregulated during growth in the constructs relative to growth in tissue culture media alone, suggesting a fungal metabolic shift towards protein catabolism. Taken together, our results indicate that this 3D-stromal model provides a physiologically relevant system to study host and fungal cell pathobiology during FK.


Assuntos
Aspergilose/microbiologia , Ceratócitos da Córnea/microbiologia , Úlcera da Córnea/microbiologia , Infecções Oculares Fúngicas/microbiologia , Fusariose/microbiologia , Interações Hospedeiro-Patógeno/fisiologia , Animais , Aspergilose/metabolismo , Aspergilose/patologia , Aspergillus fumigatus/fisiologia , Técnicas de Cultura de Células , Ceratócitos da Córnea/metabolismo , Substância Própria/metabolismo , Substância Própria/microbiologia , Substância Própria/ultraestrutura , Úlcera da Córnea/metabolismo , Úlcera da Córnea/patologia , Citocinas/metabolismo , Modelos Animais de Doenças , Infecções Oculares Fúngicas/metabolismo , Infecções Oculares Fúngicas/patologia , Fusariose/metabolismo , Fusariose/patologia , Fusarium/fisiologia , Humanos , Masculino , Metaloproteinases da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Reação em Cadeia da Polimerase em Tempo Real
17.
NPJ Biofilms Microbiomes ; 7(1): 33, 2021 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-33846334

RESUMO

Soil microbiome manipulation can potentially reduce the use of pesticides by improving the ability of soils to resist or recover from pathogen infestation, thus generating natural suppressiveness. We simulated disturbance through soil fumigation and investigated how the subsequent application of bio-organic and organic amendments reshapes the taxonomic and functional potential of the soil microbiome to suppress the pathogens Ralstonia solanacearum and Fusarium oxysporum in tomato monocultures. The use of organic amendment alone generated smaller shifts in bacterial and fungal community composition and no suppressiveness. Fumigation directly decreased F. oxysporum and induced drastic changes in the soil microbiome. This was further converted from a disease conducive to a suppressive soil microbiome due to the application of organic amendment, which affected the way the bacterial and fungal communities were reassembled. These direct and possibly indirect effects resulted in a highly efficient disease control rate, providing a promising strategy for the control of the diseases caused by multiple pathogens.


Assuntos
Antibiose , Fusarium/fisiologia , Microbiota , Ralstonia solanacearum/fisiologia , Microbiologia do Solo , Carga Bacteriana , Biodiversidade , Interações Hospedeiro-Patógeno , Lycopersicon esculentum/microbiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/terapia
18.
Int J Mol Sci ; 22(6)2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33809411

RESUMO

Fusarium wilt caused by Fusarium oxysporum f. sp. cubense (Foc) is one of the most destructive diseases of banana. Methods to control the disease are still inadequate. The present investigation targeted expression of defense-related genes in tissue cultured banana plantlets of Fusarium resistant and susceptible cultivars after infection with biological control agents (BCAs) and Fusarium (Foc race 1). In total 3034 differentially expressed genes were identified which annotated to 58 transcriptional families (TF). TF families such as MYB, bHLH and NAC TFs were mostly up-regulated in response to pathogen stress, whereas AP2/EREBP were mostly down-regulated. Most genes were associated with plant-pathogen response, plant hormone signal transduction, starch and sucrose metabolism, cysteine and methionine metabolism, flavonoid biosynthesis, selenocompound metabolism, phenylpropanoid biosynthesis, mRNA surveillance pathway, mannose type O-glycan biosynthesis, amino acid and nucleotide sugar metabolism, cyanoamino acid metabolism, and hormone signal transduction. Our results showed that the defense mechanisms of resistant and susceptible banana cultivars treated with BCAs, were regulated by differentially expressed genes in various categories of defense pathways. Furthermore, the association with different resistant levels might serve as a strong foundation for the control of Fusarium wilt of banana.


Assuntos
Resistência à Doença/genética , Fusarium/fisiologia , Perfilação da Expressão Gênica , Musa/genética , Musa/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Transcriptoma/genética , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Redes Reguladoras de Genes , Anotação de Sequência Molecular , Polimorfismo Genético , Mapas de Interação de Proteínas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
19.
Microbiol Res ; 248: 126767, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33873138

RESUMO

Xylanase secreted by Trichoderma asperellum ACCC30536 can stimulate the systemic resistance of host plants against pathogenic fungi. Following T. asperellum conidia co-culture with Populus davidiana × P. alba var. pyramidalis Louche (PdPap) seedlings, the expression of xylanases TasXyn29.4 and TasXyn24.2 in T. asperellum were upregulated, peaking at 12 h, by 106 (26.74) and 10.1 (23.34)-fold compared with the control, respectively. However, the expression of TasXyn24.4 and TasXyn24.0 was not detected. When recombinant xylanases rTasXyn29.4 and rTasXyn24.2 were heterologously expressed in Pichia pastoris GS115, their activities reached 18.9 IU/mL and 20.4 IU/mL, respectively. In PdPap seedlings induced by rTasXyn29.4 and rTasXyn24.2, the auxin and jasmonic acid signaling pathways were activated to promote growth and enhance resistance against pathogens. PdPap seedlings treated with both xylanases showed increased methyl jasmonate contents at 12 hpi, reaching 122 % (127 µg/g) compared with the control. However, neither of the xylanases could induce the salicylic acid signaling pathway in PdPap seedlings. Meanwhile, both xylanases could enhance the antioxidant ability of PdPap seedlings by improving their catalase activity. Both xylanases significantly induced systemic resistance of PdPap seedlings against Alternaria alternata, Rhizoctonia solani, and Fusarium oxysporum. However, the xylanases could only be sensed by the roots of the PdPap seedlings, not the leaves. In summary, rTasXyn29.4 and rTasXyn24.2 from T. asperellum ACCC30536 promoted growth and induced systemic resistance of PdPap seedlings, which endowed the PdPap seedlings broad-spectrum resistance to phytopathogens.


Assuntos
Endo-1,4-beta-Xilanases/farmacologia , Proteínas Fúngicas/farmacologia , Hypocreales/enzimologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/farmacologia , Populus/crescimento & desenvolvimento , Alternaria/fisiologia , Ciclopentanos/imunologia , Resistência à Doença , Endo-1,4-beta-Xilanases/genética , Endo-1,4-beta-Xilanases/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fusarium/fisiologia , Regulação Fúngica da Expressão Gênica , Hypocreales/química , Hypocreales/genética , Ácidos Indolacéticos/imunologia , Oxilipinas/imunologia , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Populus/efeitos dos fármacos , Populus/imunologia , Populus/microbiologia , Rhizoctonia/fisiologia
20.
J Invertebr Pathol ; 182: 107586, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33812924

RESUMO

The aim of this study was to identify and characterize, at the molecular and transcriptional levels, sequences encoding the different members of the four families of shrimp antimicrobial peptides (AMPs) in species of the genus Farfantepenaeus. The identification of the AMP sequences was performed by in silico analysis as well as by molecular cloning and nucleotide sequencing. We identified all seven shrimp ALFs (ALF-A to ALF-G), both Type IIa and Type IIb crustins as well as two stylicins (STY1 and STY2) in Farfantepenaeus. Only two genes (PEN1/2 and PEN4) of the four-member penaeidin family (PEN1/2 to PEN5) were found and this is the first report of stylicins as well as of several additional members of ALFs, crustins and penaeidins in species of the genus Farfantepenaeus. All AMP genes have shown to be constitutively transcribed in the shrimp immune cells (hemocytes), except for ALF-G. Finally, the transcriptional profile of the different AMPs was assessed in the hemocytes of F. paulensis (pink shrimp) following an experimental infection with the opportunistic filamentous fungus Fusarium solani. We found that while the expression of ALF-B was induced at 24 h, the STY2 gene was down-regulated at 48 h post-challenge. These results provide evidence of the molecular diversity of AMPs from shrimp of the genus Farfantepenaeus in terms of sequences, biochemical properties and expression profiles in response to infectious diseases.


Assuntos
Fusarium/fisiologia , Expressão Gênica , Interações Hospedeiro-Patógeno , Penaeidae/genética , Proteínas Citotóxicas Formadoras de Poros/genética , Animais , Penaeidae/microbiologia , Proteínas Citotóxicas Formadoras de Poros/metabolismo
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