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Benjamin Schwessinger - One of the best experts on this subject based on the ideXlab platform.

  • fungal phytopathogens encode functional homologues of Plant rapid alkalinization factor ralf Peptides
    Molecular Plant Pathology, 2017
    Co-Authors: Elisha Thynne, Isabel M. L. Saur, Jaime Simbaqueba, Huw A. Ogilvie, Oliver Mead, Adam P. Taranto, Ann-maree Catanzariti, Megan C. Mcdonald, Yvonne Gonzalezcendales, Benjamin Schwessinger
    Abstract:

    In this paper we describe the presence of genes encoding close homologues of an endogenous Plant Peptide, rapid alkalinisation factor (RALF), within the genomes of 26 species of phytopathogenic fungi. Members of the RALF family are key growth factors in Plants, and the sequence of the RALF active region is well conserved between the Plant and fungal proteins. RALF1-like sequences were observed in most cases; however, RALF27-like sequences were present in the Sphaerulina musiva and Septoria populicola genomes. These two species are pathogens of poplar and interestingly, the closest relative to their respective RALF genes is a poplar RALF27-like sequence. RALF Peptides control cellular expansion during Plant development, but were originally defined based on their ability to induce rapid alkalinisation in tobacco cell cultures. To test whether the fungal RALF Peptides were biologically active in Plants, we synthesized RALF Peptides corresponding to those encoded by two sequenced genomes of the tomato pathogen Fusarium oxysporum f. sp. lycopersici. One of these Peptides inhibited the growth of tomato seedlings and elicited responses in tomato and Nicotiana benthamiana typical of endogenous Plant RALF Peptides (ROS burst, induced alkalinisation and MAP kinas activation). Gene expression analysis confirmed that a RALF-encoding gene in Fusarium oxysporum f. sp. lycopersici was expressed during infection on tomato. However a subsequent reverse genetics approach revealed that the RALF Peptide was not required by Fusarium oxysporum f. sp. lycopersici for infection on tomato roots. This study has demonstrated the presence of functionally active RALF Peptides encoded within phytopathogens that harbour an as yet undetermined role in the Plant-pathogen interactions. This article is protected by copyright. All rights reserved.

  • a microbially derived tyrosine sulfated Peptide mimics a Plant Peptide hormone
    New Phytologist, 2017
    Co-Authors: Benjamin Schwessinger, Rory Pruitt, Anna Joe, Weiguo Zhang, Wei Feng, Valley Stewart, Jose R Dinneny
    Abstract:

    Summary The biotrophic pathogen Xanthomonas oryzae pv. oryzae (Xoo) produces a sulfated Peptide named RaxX, which shares similarity to Peptides in the PSY (Plant Peptide containing sulfated tyrosine) family. We hypothesize that RaxX mimics the growth-stimulating activity of PSY Peptides. Root length was measured in Arabidopsis and rice treated with synthetic RaxX Peptides. We also used comparative genomic analyses and reactive oxygen species burst assays to evaluate the activity of RaxX and PSY Peptides. Here we found that a synthetic sulfated RaxX derivative comprising 13 residues (RaxX13-sY), highly conserved between RaxX and PSY, induces root growth in Arabidopsis and rice in a manner similar to that triggered by PSY. We identified residues that are required for activation of immunity mediated by the rice XA21 receptor but that are not essential for root growth induced by PSY. Finally, we showed that a Xanthomonas strain lacking raxX is impaired in virulence. These findings suggest that RaxX serves as a molecular mimic of PSY Peptides to facilitate Xoo infection and that XA21 has evolved the ability to recognize and respond specifically to the microbial form of the Peptide.

  • a microbially derived tyrosine sulfated Peptide mimics a Plant Peptide hormone
    bioRxiv, 2017
    Co-Authors: Rory Pruitt, Benjamin Schwessinger, Anna Joe, Weiguo Zhang, Wei Feng, Valley Stewart, Jose R Dinneny, Pamela C Ronald
    Abstract:

    ·The biotrophic pathogen Xanthomonas oryzae pv. oryzae (Xoo) produces a sulfated Peptide named RaxX, which shares similarity to Peptides in the PSY (Plant Peptide containing sulfated tyrosine) family. We hypothesize that RaxX functionally mimics the growth stimulating activity of PSY Peptides. ·Root length was measured in Arabidopsis and rice treated with synthetic RaxX Peptides. We also used comparative genomic analysis and Reactive Oxygen Species (ROS) burst assay to evaluate the activity of RaxX and PSY Peptides. ·Here we found that a synthetic sulfated RaxX derivative comprising 13 residues (RaxX13-sY), highly conserved between RaxX and PSY, induces root growth in Arabidopsis and rice in a manner similar to that triggered by PSY. We identified residues that are required for activation of immunity mediated by the rice XA21 receptor but that are not essential for root growth induced by PSY. Finally, we showed that a Xanthomonas strain lacking raxX is impaired in virulence. ·These findings suggest that RaxX serves as a molecular mimic of PSY Peptides to facilitate Xoo infection and that XA21 has evolved the ability to recognize and respond specifically to the microbial form of the Peptide.

Margret Sauter - One of the best experts on this subject based on the ideXlab platform.

  • sulfated Plant Peptide hormones
    Journal of Experimental Botany, 2019
    Co-Authors: Christine Kaufmann, Margret Sauter
    Abstract:

    Sulfated Peptides are Plant hormones that are active at nanomolar concentrations. The sulfation at one or more tyrosine residues is catalysed by tyrosylprotein sulfotransferase (TPST), which is encoded by a single-copy gene. The sulfate group is provided by the co-substrate 3´-phosphoadenosine 5´-phosphosulfate (PAPS), which links synthesis of sulfated signaling Peptides to sulfur metabolism. The precursor proteins share a conserved DY-motif that is implicated in specifying tyrosine sulfation. Several sulfated Peptides undergo additional modification such as hydroxylation of proline and glycosylation of hydroxyproline. The modifications render the secreted signaling molecules active and stable. Several sulfated signaling Peptides have been shown to be perceived by leucine-rich repeat receptor-like kinases (LRR-RLKs) but have signaling pathways that, for the most part, are yet to be elucidated. Sulfated Peptide hormones regulate growth and a wide variety of developmental processes, and intricately modulate immunity to pathogens. While basic research on sulfated Peptides has made steady progress, their potential in agricultural and pharmaceutical applications has yet to be explored.

  • conserved phosphorylation sites in the activation loop of the arabidopsis phytosulfokine receptor pskr1 differentially affect kinase and receptor activity
    Biochemical Journal, 2015
    Co-Authors: Jens Hartmann, Dennis Linke, Christine Bonniger, Andreas Tholey, Margret Sauter
    Abstract:

    PSK (phytosulfokine) is a Plant Peptide hormone perceived by a leucine-rich repeat receptor kinase. Phosphosite mapping of epitope-tagged PSKR1 (phytosulfokine receptor 1) from Arabidopsis thaliana Plants identified Ser(696) and Ser(698) in the JM (juxtamembrane) region and probably Ser(886) and/or Ser(893) in the AL (activation loop) as in Planta phosphorylation sites. In vitro-expressed kinase was autophosphorylated at Ser(717) in the JM, and at Ser(733), Thr(752), Ser(783), Ser(864), Ser(911), Ser(958) and Thr(998) in the kinase domain. The LC-ESI-MS/MS spectra provided support that up to three sites (Thr(890), Ser(893) and Thr(894)) in the AL were likely to be phosphorylated in vitro. These sites are evolutionarily highly conserved in PSK receptors, indicative of a conserved function. Site-directed mutagenesis of the four conserved residues in the activation segment, Thr(890), Ser(893), Thr(894) and Thr(899), differentially altered kinase activity in vitro and growth-promoting activity in Planta. The T899A and the quadruple-mutated TSTT-A (T890A/S893A/T894A/T899A) mutants were both kinase-inactive, but PSKR1(T899A) retained growth-promoting activity. The T890A and S893A/T894A substitutions diminished kinase activity and growth promotion. We hypothesize that phosphorylation within the AL activates kinase activity and receptor function in a gradual and distinctive manner that may be a means to modulate the PSK response.

  • phytosulfokine Peptide signalling
    Journal of Experimental Botany, 2015
    Co-Authors: Margret Sauter
    Abstract:

    Phytosulfokine (PSK) belongs to the group of Plant Peptide growth factors. It is a disulfated pentaPeptide encoded by precursor genes that are ubiquitously present in higher Plants, suggestive of universal functions. Processing of the preproprotein involves sulfonylation by a tyrosylprotein sulfotransferase in the trans-golgi and proteolytic cleavage in the apoplast. The secreted Peptide is perceived at the cell surface by a membrane-bound receptor kinase of the leucine-rich repeat family. The PSK receptor PSKR1 from Arabidopsis thaliana is an active kinase and has guanylate cyclase activity resulting in dual-signal outputs. Receptor activity is regulated by calmodulin. While PSK may be an autocrine growth factor, it also acts non-cell autonomously by promoting growth of cells that are receptor-deficient. In Planta, PSK has multiple functions. It promotes cell growth, acts in the quiescent centre cells of the root apical meristem, contributes to funicular pollen tube guidance, and differentially alters immune responses depending on the pathogen. It has been suggested that PSK integrates growth and defence signals to balance the competing metabolic costs of these responses. This review summarizes our current understanding of PSK synthesis, signalling, and activity.

Rory Pruitt - One of the best experts on this subject based on the ideXlab platform.

  • a microbially derived tyrosine sulfated Peptide mimics a Plant Peptide hormone
    New Phytologist, 2017
    Co-Authors: Benjamin Schwessinger, Rory Pruitt, Anna Joe, Weiguo Zhang, Wei Feng, Valley Stewart, Jose R Dinneny
    Abstract:

    Summary The biotrophic pathogen Xanthomonas oryzae pv. oryzae (Xoo) produces a sulfated Peptide named RaxX, which shares similarity to Peptides in the PSY (Plant Peptide containing sulfated tyrosine) family. We hypothesize that RaxX mimics the growth-stimulating activity of PSY Peptides. Root length was measured in Arabidopsis and rice treated with synthetic RaxX Peptides. We also used comparative genomic analyses and reactive oxygen species burst assays to evaluate the activity of RaxX and PSY Peptides. Here we found that a synthetic sulfated RaxX derivative comprising 13 residues (RaxX13-sY), highly conserved between RaxX and PSY, induces root growth in Arabidopsis and rice in a manner similar to that triggered by PSY. We identified residues that are required for activation of immunity mediated by the rice XA21 receptor but that are not essential for root growth induced by PSY. Finally, we showed that a Xanthomonas strain lacking raxX is impaired in virulence. These findings suggest that RaxX serves as a molecular mimic of PSY Peptides to facilitate Xoo infection and that XA21 has evolved the ability to recognize and respond specifically to the microbial form of the Peptide.

  • a microbially derived tyrosine sulfated Peptide mimics a Plant Peptide hormone
    bioRxiv, 2017
    Co-Authors: Rory Pruitt, Benjamin Schwessinger, Anna Joe, Weiguo Zhang, Wei Feng, Valley Stewart, Jose R Dinneny, Pamela C Ronald
    Abstract:

    ·The biotrophic pathogen Xanthomonas oryzae pv. oryzae (Xoo) produces a sulfated Peptide named RaxX, which shares similarity to Peptides in the PSY (Plant Peptide containing sulfated tyrosine) family. We hypothesize that RaxX functionally mimics the growth stimulating activity of PSY Peptides. ·Root length was measured in Arabidopsis and rice treated with synthetic RaxX Peptides. We also used comparative genomic analysis and Reactive Oxygen Species (ROS) burst assay to evaluate the activity of RaxX and PSY Peptides. ·Here we found that a synthetic sulfated RaxX derivative comprising 13 residues (RaxX13-sY), highly conserved between RaxX and PSY, induces root growth in Arabidopsis and rice in a manner similar to that triggered by PSY. We identified residues that are required for activation of immunity mediated by the rice XA21 receptor but that are not essential for root growth induced by PSY. Finally, we showed that a Xanthomonas strain lacking raxX is impaired in virulence. ·These findings suggest that RaxX serves as a molecular mimic of PSY Peptides to facilitate Xoo infection and that XA21 has evolved the ability to recognize and respond specifically to the microbial form of the Peptide.

Eleonora Kurtenbach - One of the best experts on this subject based on the ideXlab platform.

  • antifungal pisum sativum defensin 1 interacts with neurospora crassa cyclin f related to the cell cycle
    Biochemistry, 2007
    Co-Authors: Denise S Lobo, Iuri B Pereira, Lucianne Fragelmadeira, Luciano Neves De Medeiros, Luiz M Cabral, Jane Faria, Maria Bellio, Reinaldo Calixto De Campos, Rafael Linden, Eleonora Kurtenbach
    Abstract:

    Plant defensins, components of the Plant innate immune system, are cationic cysteine-rich antifungal Peptides. Evidence from the literature [Thevissen, K., et al. (2003) Peptides 24, 1705-1712] has demonstrated that patches of fungi membrane containing mannosyldiinositolphosphorylceramide and glucosylceramides are selective binding sites for the Plant defensins isolated from Dahlia merckii and Raphanus sativus, respectively. Whether Plant defensins interact directly or indirectly with fungus intracellular targets is unknown. To identify physical protein-protein interactions, a GAL4-based yeast two-hybrid system was performed using the antifungal Plant Peptide Pisum sativum defensin 1 (Psd1) as the bait. Target proteins were screened within a Neurospora crassa cDNA library. Nine out of 11 two-hybrid candidates were nuclear proteins. One clone, detected with high frequency per screening, presented sequence similarity to a cyclin-like protein, with F-box and WD-repeat domains, related to the cell cycle control. GST pull-down assay corroborated in vitro this two-hybrid interaction. Fluorescence microscopy analysis of FITC-conjugated Psd1 and DAPI-stained fungal nuclei showed in vivo the colocalization of the Plant Peptide Psd1 and the nucleus. Analysis of the DNA content of N. crassa conidia using flow cytometry suggested that Psd1 directed cell cycle impairment and caused conidia to undergo endoreduplication. The developing retina of neonatal rats was used as a model to observe the interkinetic nuclear migration during proliferation of an organized tissue from the S toward the M phase of the cell cycle in the presence of Psd1. The results demonstrated that the Plant defensin Psd1 regulates interkinetic nuclear migration in retinal neuroblasts.

  • antifungal pisum sativum defensin 1 interacts with neurospora crassa cyclin f related to the cell cycle
    Biochemistry, 2007
    Co-Authors: Denise S Lobo, Iuri B Pereira, Lucianne Fragelmadeira, Luciano Neves De Medeiros, Luiz M Cabral, Jane Faria, Maria Bellio, Reinaldo Calixto De Campos, Rafael Linden, Eleonora Kurtenbach
    Abstract:

    Plant defensins, components of the Plant innate immune system, are cationic cysteine-rich antifungal Peptides. Evidence from the literature [Thevissen, K., et al. (2003) Peptides 24, 1705−1712] has demonstrated that patches of fungi membrane containing mannosyldiinositolphosphorylceramide and glucosylceramides are selective binding sites for the Plant defensins isolated from Dahlia merckii and Raphanus sativus, respectively. Whether Plant defensins interact directly or indirectly with fungus intracellular targets is unknown. To identify physical protein−protein interactions, a GAL4-based yeast two-hybrid system was performed using the antifungal Plant Peptide Pisum sativum defensin 1 (Psd1) as the bait. Target proteins were screened within a Neurospora crassa cDNA library. Nine out of 11 two-hybrid candidates were nuclear proteins. One clone, detected with high frequency per screening, presented sequence similarity to a cyclin-like protein, with F-box and WD-repeat domains, related to the cell cycle contr...

Jose R Dinneny - One of the best experts on this subject based on the ideXlab platform.

  • a microbially derived tyrosine sulfated Peptide mimics a Plant Peptide hormone
    New Phytologist, 2017
    Co-Authors: Benjamin Schwessinger, Rory Pruitt, Anna Joe, Weiguo Zhang, Wei Feng, Valley Stewart, Jose R Dinneny
    Abstract:

    Summary The biotrophic pathogen Xanthomonas oryzae pv. oryzae (Xoo) produces a sulfated Peptide named RaxX, which shares similarity to Peptides in the PSY (Plant Peptide containing sulfated tyrosine) family. We hypothesize that RaxX mimics the growth-stimulating activity of PSY Peptides. Root length was measured in Arabidopsis and rice treated with synthetic RaxX Peptides. We also used comparative genomic analyses and reactive oxygen species burst assays to evaluate the activity of RaxX and PSY Peptides. Here we found that a synthetic sulfated RaxX derivative comprising 13 residues (RaxX13-sY), highly conserved between RaxX and PSY, induces root growth in Arabidopsis and rice in a manner similar to that triggered by PSY. We identified residues that are required for activation of immunity mediated by the rice XA21 receptor but that are not essential for root growth induced by PSY. Finally, we showed that a Xanthomonas strain lacking raxX is impaired in virulence. These findings suggest that RaxX serves as a molecular mimic of PSY Peptides to facilitate Xoo infection and that XA21 has evolved the ability to recognize and respond specifically to the microbial form of the Peptide.

  • a microbially derived tyrosine sulfated Peptide mimics a Plant Peptide hormone
    bioRxiv, 2017
    Co-Authors: Rory Pruitt, Benjamin Schwessinger, Anna Joe, Weiguo Zhang, Wei Feng, Valley Stewart, Jose R Dinneny, Pamela C Ronald
    Abstract:

    ·The biotrophic pathogen Xanthomonas oryzae pv. oryzae (Xoo) produces a sulfated Peptide named RaxX, which shares similarity to Peptides in the PSY (Plant Peptide containing sulfated tyrosine) family. We hypothesize that RaxX functionally mimics the growth stimulating activity of PSY Peptides. ·Root length was measured in Arabidopsis and rice treated with synthetic RaxX Peptides. We also used comparative genomic analysis and Reactive Oxygen Species (ROS) burst assay to evaluate the activity of RaxX and PSY Peptides. ·Here we found that a synthetic sulfated RaxX derivative comprising 13 residues (RaxX13-sY), highly conserved between RaxX and PSY, induces root growth in Arabidopsis and rice in a manner similar to that triggered by PSY. We identified residues that are required for activation of immunity mediated by the rice XA21 receptor but that are not essential for root growth induced by PSY. Finally, we showed that a Xanthomonas strain lacking raxX is impaired in virulence. ·These findings suggest that RaxX serves as a molecular mimic of PSY Peptides to facilitate Xoo infection and that XA21 has evolved the ability to recognize and respond specifically to the microbial form of the Peptide.