scholarly journals A fungal ribonuclease-like effector protein inhibits plant host ribosomal RNA degradation

2018 ◽  
Author(s):  
Helen G. Pennington ◽  
Rhian Jones ◽  
Seomun Kwon ◽  
Giulia Bonciani ◽  
Hannah Thieron ◽  
...  
Keyword(s):  
Rna Degradation ◽  
In Planta ◽  
Glutathione S Transferase ◽  
Plant Host ◽  
Translation Elongation ◽  
Transgenic Expression ◽  
Susceptibility To Infection ◽  
Host Cell Death ◽  
Dicotyledonous Plants ◽  
Related Proteins

ABSTRACTThe biotrophic fungal pathogen Blumeria graminis causes the powdery mildew disease of cereals and grasses. Proteins with a predicted ribonuclease (RNase)-like fold (termed RALPHs) comprise the largest set of secreted effector candidates within the B. graminis f. sp. hordei genome. Their exceptional abundance suggests they play crucial functions during pathogenesis. We show that transgenic expression of RALPH CSEP0064/BEC1054 increases susceptibility to infection in monocotyledenous and dicotyledonous plants. CSEP0064/BEC1054 interacts in planta with five host proteins: two translation elongation factors (eEF1α and eEF1γ), two pathogenesis-related proteins (PR5 and PR10) and a glutathione-S-transferase. We present the first crystal structure of a RALPH, CSEP0064/BEC1054, demonstrating it has an RNase-like fold. The protein interacts with total RNA and weakly with DNA. Methyl jasmonate levels modulate susceptibility to aniline-induced host RNA fragmentation. In planta expression of CSEP0064/BEC1054 reduces the formation of this RNA fragment. We propose that CSEP0064/BEC1054 is a pseudoenzyme that binds to host ribosomes, thereby inhibiting the action of plant ribosome-inactivating proteins that would otherwise lead to host cell death, an unviable interaction and demise of the fungus.

scholarly journals Survival trade-offs in plant roots during colonization by closely related beneficial and pathogenic fungi

2016 ◽  
Vol 7 (1) ◽  
Author(s):  
Stéphane Hacquard ◽  
Barbara Kracher ◽  
Kei Hiruma ◽  
Philipp C. Münch ◽  
Ruben Garrido-Oter ◽  
...  
Keyword(s):  
Sufficient Conditions ◽  
Pathogenic Fungi ◽  
Defense Responses ◽  
Effector Proteins ◽  
In Planta ◽  
Plant Host ◽  
Genomic Signatures ◽  
Trade Offs ◽  
Related Proteins ◽  
Similar Gene

Abstract The sessile nature of plants forced them to evolve mechanisms to prioritize their responses to simultaneous stresses, including colonization by microbes or nutrient starvation. Here, we compare the genomes of a beneficial root endophyte, Colletotrichum tofieldiae and its pathogenic relative C. incanum, and examine the transcriptomes of both fungi and their plant host Arabidopsis during phosphate starvation. Although the two species diverged only 8.8 million years ago and have similar gene arsenals, we identify genomic signatures indicative of an evolutionary transition from pathogenic to beneficial lifestyles, including a narrowed repertoire of secreted effector proteins, expanded families of chitin-binding and secondary metabolism-related proteins, and limited activation of pathogenicity-related genes in planta. We show that beneficial responses are prioritized in C. tofieldiae-colonized roots under phosphate-deficient conditions, whereas defense responses are activated under phosphate-sufficient conditions. These immune responses are retained in phosphate-starved roots colonized by pathogenic C. incanum, illustrating the ability of plants to maximize survival in response to conflicting stresses.

scholarly journals Interactions with Hosts at Cool Temperatures, Not Cold Tolerance, Explain the Unique Epidemiology of Ralstonia solanacearum Race 3 Biovar 2

2009 ◽  
Vol 99 (10) ◽  
pp. 1127-1134 ◽  
Author(s):  
Annett Milling ◽  
Fanhong Meng ◽  
Timothy P. Denny ◽  
Caitilyn Allen
Keyword(s):  
North American ◽  
Ralstonia Solanacearum ◽  
Potato Tubers ◽  
In Planta ◽  
Plant Host ◽  
Tomato Plants ◽  
North American Strain ◽  
Tropical Highlands ◽  
American Strain ◽  
Warm Temperate

Most strains of the bacterial wilt pathogen Ralstonia solanacearum are tropical, but race 3 biovar 2 (R3bv2) strains can attack plants in temperate zones and tropical highlands. The basis of this distinctive ecological trait is not understood. We compared the survival of tropical, R3bv2, and warm-temperate North American strains of R. solanacearum under different conditions. In water at 4°C, North American strains remained culturable the longest (up to 90 days), whereas tropical strains remained culturable for the shortest time (≈40 days). However, live/dead staining indicated that cells of representative strains remained viable for >160 days. In contrast, inside potato tubers, R3bv2 strain UW551 survived >4 months at 4°C, whereas North American strain K60 and tropical strain GMI1000 were undetectable after <70 days in tubers. GMI1000 and UW551 grew similarly in minimal medium at 20 and 28°C and, although both strains wilted tomato plants rapidly at 28°C, UW551 was much more virulent at 20°C, killing all inoculated plants under conditions where GMI100 killed just over half. Thus, differences among the strains in the absence of a plant host were not predictive of their behavior in planta at cooler temperatures. These data indicate that interaction with plants is required for expression of the temperate epidemiological trait of R3bv2.

scholarly journals Molecular Insights into Defense Responses of Vietnamese Maize Varieties to Fusarium verticillioides Isolates

2021 ◽  
Vol 7 (9) ◽  
pp. 724
Author(s):  
Trang Minh Tran ◽  
Maarten Ameye ◽  
Sofie Landschoot ◽  
Frank Devlieghere ◽  
Sarah De Saeger ◽  
...  
Keyword(s):  
Expression Profiles ◽  
Fusarium Verticillioides ◽  
Gene Expression Profiles ◽  
Defense Responses ◽  
Ear Rot ◽  
In Planta ◽  
Resistant Lines ◽  
Maize Varieties ◽  
Pathogenesis Related ◽  
Related Proteins

Fusarium ear rot (FER) caused by Fusarium verticillioides is one of the main fungal diseases in maize worldwide. To develop a pathogen-tailored FER resistant maize line for local implementation, insights into the virulence variability of a residing F. verticillioides population are crucial for developing customized maize varieties, but remain unexplored. Moreover, little information is currently available on the involvement of the archetypal defense pathways in the F. verticillioides–maize interaction using local isolates and germplasm, respectively. Therefore, this study aims to fill these knowledge gaps. We used a collection of 12 F. verticillioides isolates randomly gathered from diseased maize fields in the Vietnamese central highlands. To assess the plant’s defense responses against the pathogens, two of the most important maize hybrid genotypes grown in this agro-ecological zone, lines CP888 and Bt/GT NK7328, were used. Based on two assays, a germination and an in-planta assay, we found that line CP888 was more susceptible to the F. verticillioides isolates when compared to line Bt/GT NK7328. Using the most aggressive isolate, we monitored disease severity and gene expression profiles related to biosynthesis pathways of salicylic acid (SA), jasmonic acid (JA), abscisic acid (ABA), benzoxazinoids (BXs), and pathogenesis-related proteins (PRs). As a result, a stronger induction of SA, JA, ABA, BXs, and PRs synthesizing genes might be linked to the higher resistance of line Bt/GT NK7328 compared to the susceptible line CP888. All these findings could supply valuable knowledge in the selection of suitable FER resistant lines against the local F. verticllioides population and in the development of new FER resistant germplasms.

scholarly journals The landscape of cytokinin binding by a plant nodulin

2013 ◽  
Vol 69 (12) ◽  
pp. 2365-2380 ◽  
Author(s):  
M. Ruszkowski ◽  
K. Szpotkowski ◽  
M. Sikorski ◽  
M. Jaskolski
Keyword(s):  
Root Nodules ◽  
Outer Cortex ◽  
Plant Host ◽  
Symbiotic Interaction ◽  
Model Legume ◽  
Hydrophobic Cavity ◽  
Density Maps ◽  
Loop Element ◽  
Α Helix ◽  
Related Proteins

Nodulation is an extraordinary symbiotic interaction between leguminous plants and nitrogen-fixing bacteria (rhizobia) that assimilate atmospheric nitrogen (in root nodules) and convert it into compounds suitable for the plant host. A class of plant hormones called cytokinins are involved in the nodulation process. In the model legumeMedicago truncatula, nodulin 13 (MtN13), which belongs to the pathogenesis-related proteins of class 10 (PR-10), is expressed in the outer cortex of the nodules. In general, PR-10 proteins are small and monomeric and have a characteristic fold with an internal hydrophobic cavity formed between a seven-stranded antiparallel β-sheet and a C-terminal α-helix. Previously, some PR-10 proteins not related to nodulation were found to bind cytokinins such astrans-zeatin. Here, four crystal structures of the MtN13 protein are reported in complexes with several cytokinins, namelytrans-zeatin,N6-isopentenyladenine, kinetin andN6-benzyladenine. All four phytohormones are bound in the hydrophobic cavity in the same manner and have excellent definition in the electron-density maps. The binding of the cytokinins appears to be strong and specific and is reinforced by several hydrogen bonds. Although the binding stoichiometry is 1:1, the complex is actually dimeric, with a cytokinin molecule bound in each subunit. The ligand-binding site in each cavity is formed with the participation of a loop element from the other subunit, which plugs the only entrance to the cavity. Interestingly, a homodimer of MtN13 is also formed in solution, as confirmed by small-angle X-ray scattering (SAXS).

scholarly journals Nanosphere Loaded With Curcumin Inhibits the Gastrointestinal Cell Death Signaling Pathway Induced by the Foodborne Pathogen Vibrio vulnificus

Cells ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 631 ◽  
Author(s):  
Ji-Yun Kim ◽  
Young-Min Lee ◽  
Do-Wan Kim ◽  
Taesun Min ◽  
Sei-Jung Lee
Keyword(s):  
Cell Death ◽  
Signaling Pathway ◽  
Vibrio Vulnificus ◽  
Foodborne Pathogen ◽  
Herbal Supplement ◽  
Host Cell Death ◽  
Infection Treatment ◽  
Major Factors ◽  
Related Proteins ◽  
Ht 29

Curcumin, a hydrophobic polyphenol of turmeric, has a variety of biological functions as a herbal supplement, but its poor gastric absorption rate is one of the major factors limiting its oral bioavailability. In the present study, we have investigated the functional role of a nanosphere loaded with curcumin (CN) during host cell death elicited by the Gram-negative bacterium V. vulnificus in human gastrointestinal epithelial HT-29 cells and an ileal-ligated mouse model. The recombinant protein (r) VvhA produced by V. vulnificus significantly reduced the viability of HT-29 cells. The cytotoxic effect of rVvhA was restored upon a treatment with CN (100 ng/mL), which had shown 1000-fold higher anti-apoptotic efficacy than curcumin. CN inhibited the phosphorylation of c-Src and PKC mediated by intracellular ROS responsible for the distinctive activation of the MAPKs in rVvhA-treated HT-29 cells. Interestingly, CN significantly restored the expression of Bax, Bcl-2, and cleaved caspase-3 as regulated by the phosphorylation of NF-κB. In mouse models of V. vulnificus infection, treatment with CN had a blocking effect that elevated the levels of TUNEL-positive DNA fragmentation and apoptosis-related proteins. These results indicate that CN is a functional agent that manipulates the V. vulnificus VvhA signaling pathway responsible for gastrointestinal cell death.

Comparative proteomic analysis of chestnut blight fungus,Cryphonectria parasitica, under tannic-acid-inducing and hypovirus-regulating conditions

2012 ◽  
Vol 58 (7) ◽  
pp. 863-871 ◽  
Author(s):  
Jung-Mi Kim ◽  
Jin-Ah Park ◽  
Dae-Hyuk Kim
Keyword(s):  
Tannic Acid ◽  
Proteomic Analysis ◽  
Cryphonectria Parasitica ◽  
Chestnut Blight ◽  
Gene Products ◽  
Glutathione S Transferase ◽  
Chestnut Blight Fungus ◽  
Shock Proteins ◽  
Related Proteins ◽  
Hypothetical Genes

Chestnut blight fungus, Cryphonectria parasitica , and its hypovirus present a useful model system for investigating the mechanisms of hypoviral infection. To identify gene products associated with fungal pathogenicity and hypoviral regulation, we attempted a proteomic analysis of the virus-free EP155/2 strain and its isogenic virus-infected UEP1 strain in response to tannic acid (TA), which is abundant in the bark of chestnut trees. In this study, pretreatment of mycelia grown on TA-supplemented media was developed for proteomic analysis. Approximately 704 proteins from the mycelia of the EP155/2 strain were reproducibly present in 3 independent extractions. Among these, 111 and 79 spots were found to be responsive to hypovirus infection and TA supplementation, respectively. The TA-grown UEP1 strain yielded 28 spots showing an expression pattern different from that of untreated UEP1. Thirty protein spots showing considerable differences in spot density were selected for further analysis. Hybrid tandem LC-MS/MS spectrometry of the 30 selected protein spots revealed that 29 were identified while 1 was unidentified. Among the identified 29 proteins, 15 were metabolic enzymes; 5 were stress-related, of which 4 were heat-shock proteins and 1 was glutathione S-transferase; 5 were signaling and cellular process-related proteins; 2 were structural proteins; and 2 matched proteins of hypothetical genes.

scholarly journals Interactions between two fission yeast serine/arginine-rich proteins and their modulation by phosphorylation

2002 ◽  
Vol 368 (2) ◽  
pp. 527-534 ◽  
Author(s):  
Zhaohua TANG ◽  
Norbert F. KÄUFER ◽  
Ren-Jang LIN
Keyword(s):  
Alternative Splicing ◽  
Protein Phosphorylation ◽  
Fission Yeast ◽  
Protein Function ◽  
Sr Proteins ◽  
Specific Protein ◽  
Glutathione S Transferase ◽  
Sr Protein ◽  
Random Screen ◽  
Related Proteins

The unexpected low number of genes in the human genome has triggered increasing attention to alternative pre-mRNA splicing, and serine/arginine-rich (SR) proteins have been correlated with the complex alternative splicing that is a characteristic of metazoans. SR proteins interact with RNA and splicing protein factors, and they also undergo reversible phosphorylation, thereby regulating constitutive and alternative splicing in mammals and Drosophila. However, it is not clear whether the features of SR proteins and alternative splicing are present in simple and genetically tractable organisms, such as yeasts. In the present study, we show that the SR-like proteins Srp1 and Srp2, found in the fission yeast Schizosaccharomyces pombe, interact with each other and the interaction is modulated by protein phosphorylation. By using Srp1 as bait in a yeast two-hybrid analysis, we specifically isolated Srp2 from a random screen. This Srp interaction was confirmed by a glutathione-S-transferase pull-down assay. We also found that the Srp1—Srp2 complex was phosphorylated at a reduced efficiency by a fission yeast SR-specific kinase, Dis1-suppression kinase (Dsk1). Conversely, Dsk1-mediated phosphorylation inhibited the formation of the Srp complex. These findings offer the first example in fission yeast for interactions between SR-related proteins and the modulation of the interactions by specific protein phosphorylation, suggesting that a mammalian-like SR protein function may exist in fission yeast.

scholarly journals Plant-Necrotroph Co-transcriptome Networks Illuminate a Metabolic Battlefield

2018 ◽  
Author(s):  
Wei Zhang ◽  
Jason A. Corwin ◽  
Daniel Copeland ◽  
Julie Feusier ◽  
Robert Eshbaugh ◽  
...  
Keyword(s):  
Interaction Network ◽  
In Planta ◽  
Systematic Map ◽  
Plant Host ◽  
Host Pathogen Interaction ◽  
Host Pathogen ◽  
Species Dynamics ◽  
Transcriptomic Level ◽  
The Impact ◽  
Interaction Research

AbstractA central goal of studying host-pathogen interaction research is to understand how the host and pathogen manipulate each other to promote their own fitness in a pathosystem. Co-transcriptomic approaches can simultaneously analyze dual transcriptomes during infection and provide a systematic map of the cross-kingdom communication between two species. Here we used the Arabidopsis-B. cinerea pathosystem to test how plant host and fungal pathogen interaction at the transcriptomic level during infection. We assessed the impact of natural genetic diversity in the pathogen and plant host by utilization of a collection of 96 isolates of B. cinerea infection on Arabidopsis wild-type and two mutants with jasmonate or salicylic acid compromised immunities. We identified ten B. cinerea gene co-expression networks (GCNs) that encode known or novel virulence mechanisms. We constructed a dual interaction network by combining four host-and ten pathogen-GCNs into a single network, which revealed potential connections between the fungal and plant GCNs involving both novel and conserved mechanisms. These co-transcriptome data shed lights on the potential mechanisms underlying host-pathogen interaction and illustrate the continued need for advancements of in planta analysis of dual-species dynamics.

scholarly journals Transposon mutagenesis reveals Pseudomonas cannabina pv. alisalensis optimizes its virulence factors for pathogenicity on different hosts

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7698 ◽  
Author(s):  
Nanami Sakata ◽  
Takako Ishiga ◽  
Haruka Saito ◽  
Viet Tru Nguyen ◽  
Yasuhiro Ishiga
Keyword(s):  
Virulence Factors ◽  
Type Iii Secretion ◽  
Bacterial Blight ◽  
Membrane Transporters ◽  
Plant Host ◽  
Inoculation Test ◽  
Bacterial Interaction ◽  
Dicotyledonous Plants ◽  
Blight Disease ◽  
Green Manure Crops

Pseudomonas cannabina pv. alisalensis (Pcal), which causes bacterial blight disease of Brassicaceae, is an economically important pathogen worldwide. To identify Pcal genes involved in pathogenesis, we conducted a screen for 1,040 individual Pcal KB211 Tn5 mutants with reduced virulence on cabbage plants using a dip-inoculation method. We isolated 53 reduced virulence mutants and identified several potential virulence factors involved in Pcal virulence mechanisms such as the type III secretion system, membrane transporters, transcription factors, and amino acid metabolism. Importantly, Pcal is pathogenic on a range of monocotyledonous and dicotyledonous plants. Therefore, we also carried out the inoculation test on oat plants, which are cultivated after cabbage cultivation as green manure crops. Interestingly among the 53 mutants, 31 mutants also exhibited reduced virulence on oat seedlings, indicating that Pcal optimizes its virulence factors for pathogenicity on different host plants. Our results highlight the importance of revealing the virulence factors for each plant host-bacterial interaction, and will provide new insights into Pcal virulence mechanisms.

scholarly journals Coexistence of genetically different Rhizophagus irregularis isolates induces genes involved in a putative fungal mating response

2020 ◽  
Vol 14 (10) ◽  
pp. 2381-2394
Author(s):  
Ivan D. Mateus ◽  
Edward C. Rojas ◽  
Romain Savary ◽  
Cindy Dupuis ◽  
Frédéric G. Masclaux ◽  
...  
Keyword(s):  
Mycorrhizal Fungi ◽  
Arbuscular Mycorrhizal ◽  
Fungal Species ◽  
Rhizophagus Irregularis ◽  
In Planta ◽  
Host Genotype ◽  
Plant Host ◽  
Mating Response ◽  
Ecological Importance ◽  
Mat Locus

Abstract Arbuscular mycorrhizal fungi (AMF) are of great ecological importance because of their effects on plant growth. Closely related genotypes of the same AMF species coexist in plant roots. However, almost nothing is known about the molecular interactions occurring during such coexistence. We compared in planta AMF gene transcription in single and coinoculation treatments with two genetically different isolates of Rhizophagus irregularis in symbiosis independently on three genetically different cassava genotypes. Remarkably few genes were specifically upregulated when the two fungi coexisted. Strikingly, almost all of the genes with an identifiable putative function were known to be involved in mating in other fungal species. Several genes were consistent across host plant genotypes but more upregulated genes involved in putative mating were observed in host genotype (COL2215) compared with the two other host genotypes. The AMF genes that we observed to be specifically upregulated during coexistence were either involved in the mating pheromone response, in meiosis, sexual sporulation or were homologs of MAT-locus genes known in other fungal species. We did not observe the upregulation of the expected homeodomain genes contained in a putative AMF MAT-locus, but observed upregulation of HMG-box genes similar to those known to be involved in mating in Mucoromycotina species. Finally, we demonstrated that coexistence between the two fungal genotypes in the coinoculation treatments explained the number of putative mating response genes activated in the different plant host genotypes. This study demonstrates experimentally the activation of genes involved in a putative mating response and represents an important step towards the understanding of coexistence and sexual reproduction in these important plant symbionts.

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