Publications by authors named "Peter S Solomon"

is a necrotrophic pathogen of wheat that is particularly destructive in major wheat-growing regions of the United States, northern Europe, Australia, and South America. secretes necrotrophic effectors that target wheat susceptibility genes to induce programmed cell death (PCD), resulting in increased colonization of host tissue and, ultimately, sporulation to complete its pathogenic life cycle. Intensive research over the last two decades has led to the functional characterization of five proteinaceous necrotrophic effectors, , , , , and , and three wheat susceptibility genes, , , and Functional characterization has revealed that these effectors, in addition to inducing PCD, have additional roles in pathogenesis, including chitin binding that results in protection from wheat chitinases, blocking defense response signaling, and facilitating plant colonization.

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Human activity impacts the evolutionary trajectories of many species worldwide. Global trade of agricultural goods contributes to the dispersal of pathogens reshaping their genetic makeup and providing opportunities for virulence gains. Understanding how pathogens surmount control strategies and cope with new climates is crucial to predicting the future impact of crop pathogens.

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ToxA is one of the most studied proteinaceous necrotrophic effectors produced by plant pathogens. It has been identified in four pathogens (, , [formerly f. sp.

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Septoria tritici blotch (STB) has been ranked the third most important wheat disease in the world, threatening a large area of wheat production. Although major genes play an important role in the protection against infection, the lifespan of their resistance unfortunately is very short in modern wheat production systems. Combinations of quantitative resistance with minor effects, therefore, are believed to have prolonged and more durable resistance to .

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Pathogenic fungi use diverse infection strategies to obtain nutrients from plants. Biotrophic fungi feed only on living plant tissue, whereas necrotrophic fungi kill host cells to extract nutrients. To prevent disease, plants need to distinguish between pathogens with different life cycles, as a successful defense against a biotroph, which often involves programmed cell-death around the site of infection, is not an appropriate response to some necrotrophs.

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The plant pathogen Parastagonospora nodorum secretes necrotrophic effectors to promote disease. These effectors induce cell death on wheat cultivars carrying dominant susceptibility genes in an inverse gene-for-gene manner. However, the molecular mechanisms underpinning these interactions and resulting cell death remain unclear.

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Effectors are a key part of the arsenal of plant-pathogenic fungi and promote pathogen virulence and disease. Effectors typically lack sequence similarity to proteins with known functional domains and motifs, limiting our ability to predict their functions and understand how they are recognized by plant hosts. As a result, cross-disciplinary approaches involving structural biology and protein biochemistry are often required to decipher and better characterize effector function.

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Plant fungal pathogens cause devastating diseases on cereal plants and threaten global food security. During infection, these pathogens secrete proteinaceous effectors that promote disease. Some of these effectors from necrotrophic plant pathogens induce a cell death response (necrosis), which facilitates pathogen growth .

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Plant pathogens cause disease through secreted effector proteins, which act to promote infection. Typically, the sequences of effectors provide little functional information and further targeted experimentation is required. Here, we utilized a structure/function approach to study SnTox3, an effector from the necrotrophic fungal pathogen Parastagonospora nodorum, which causes cell death in wheat-lines carrying the sensitivity gene Snn3.

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Zymoseptoria tritici, the causal agent of Septoria tritici blotch, is a fungal wheat pathogen that causes significant global yield losses. Within Z. tritici populations, quantitative differences in virulence among different isolates are commonly observed; however, the genetic components that underpin these differences remain elusive.

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The effector SnTox3 from Parastagonospora nodorum elicits a strong necrotic response in susceptible wheat and also interacts with wheat pathogenesis-related protein 1 (TaPR-1), although the function of this interaction in disease is unclear. Here, we dissect TaPR1 function by studying SnTox3-TaPR1 interaction and demonstrate the dual functionality of SnTox3. We utilized site-directed mutagenesis to identify an SnTox3 variant, SnTox3 , that was unable to interact with TaPR1 in yeast-two-hybrid assays.

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Background: The fungal pathogen is a significant constraint to wheat production in temperate cropping regions around the world. Despite its agronomic impacts, the mechanisms allowing the pathogen to asymptomatically invade and grow in the apoplast of wheat leaves before causing extensive host cell death remain elusive. Given recent evidence of extracellular vesicles (EVs)-secreted, membrane-bound nanoparticles containing molecular cargo-being implicated in extracellular communication between plants and fungal pathogen, we have initiated an in vitro investigation of EVs from this apoplastic fungal wheat pathogen.

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The necrotrophic fungal pathogen produces victorin, a host-selective toxin (HST) essential for pathogenicity to certain oat cultivars with resistance against crown rust. Victorin is a mixture of highly modified heterodetic cyclic hexapeptides, previously assumed to be synthesized by a nonribosomal peptide synthetase. Herein, we demonstrate that victorin is a member of the ribosomally synthesized and posttranslationally modified peptide (RiPP) family of natural products.

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Septoria nodorum blotch is a major disease of wheat caused by the fungus . Recent studies have demonstrated that secondary metabolites, including polyketides and non-ribosomal peptides, produced by the pathogen play important roles in disease and development. However, there is currently no knowledge on the composition or biological activity of the volatile organic compounds (VOCs) secreted by .

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Background: The genome-editing tool CRISPR/Cas9 has revolutionized gene manipulation by providing an efficient method to generate targeted mutations. This technique deploys the Cas9 endonuclease and a guide RNA (sgRNA) which interact to form a Cas9-sgRNA complex that initiates gene editing through the introduction of double stranded DNA breaks. We tested the efficacy of the CRISPR/Cas9 approach as a means of facilitating a variety of reverse genetic approaches in the wheat pathogenic fungus .

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The etiology of fungal pathogenesis of grains is critical to global food security. The large number of orphan biosynthetic gene clusters uncovered in fungal plant pathogen genome sequencing projects suggests that we have a significant knowledge gap about the secondary metabolite repertoires of these pathogens and their roles in plant pathogenesis. Cytochalasans are a family of natural products of significant interest due to their ability to bind to actin and interfere with cellular processes that involved actin polymerization; however, our understanding of their biosynthesis and biological roles remains incomplete.

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The fungus Parastagonospora nodorum infects wheat through the use of necrotrophic effector (NE) proteins that cause host-specific tissue necrosis. The ZnCys transcription factor PnPf2 positively regulates NE gene expression and is required for virulence on wheat. Little is known about other downstream targets of PnPf2.

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The aldol reaction is one of the most fundamental stereocontrolled carbon-carbon bond-forming reactions and is mainly catalyzed by aldolases in nature. Despite the fact that the aldol reaction has been widely proposed to be involved in fungal secondary metabolite biosynthesis, a dedicated aldolase that catalyzes stereoselective aldol reactions has only rarely been reported in fungi. Herein, we activated a cryptic polyketide biosynthetic gene cluster that was upregulated in the fungal wheat pathogen Parastagonospora nodorum during plant infection; this resulted in the production of the phytotoxic stemphyloxin II (1).

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Most known examples of horizontal gene transfer (HGT) between eukaryotes are ancient. These events are identified primarily using phylogenetic methods on coding regions alone. Only rarely are there examples of HGT where noncoding DNA is also reported.

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Chemical investigation of the barley and wheat fungal pathogen BRIP10943 yielded four new sativene-type sesquiterpenoid natural products, bipolenins K-N (-), together with seven related known analogues (-), and a sesterterpenoid (). Their structures were determined by detailed analysis of spectroscopic data, supported by TDDFT calculations and comparison with previously reported analogues. These compounds were evaluated for their phytotoxic activity against wheat seedlings and wheat seed germination.

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White grain disorder is a recently emerged wheat disease in Australia, caused by Eutiarosporella darliae, E. pseudodarliae, and E. tritici-australis.

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is a globally distributed fungal pathogen which causes Septoria tritici blotch on wheat. Management of the disease is attempted through the deployment of resistant wheat cultivars and the application of fungicides. However, fungicide resistance is commonly observed in populations, and continuous monitoring is required to detect breakdowns in fungicide efficacy.

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A new and dominant R gene Stb19 is identified from a soft wheat cultivar 'Lorikeet' and was mapped on the distal region of chromosome 1DS. Two tightly linked KASP markers were also discovered and validated for molecular-assisted breeding programs. A new R gene, designated as Stb19, provides resistance to Zymoseptoria tritici in wheat.

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