A single NLR gene confers resistance to leaf and stripe rust in wheat.

Nucleotide-binding leucine-rich repeat (NLR) disease resistance genes typically confer resistance against races of a single pathogen. Here, we report that Yr87/Lr85, an NLR gene from Aegilops sharonensis and Aegilops longissima, confers resistance against both P. striiformis tritici (Pst) and Puccinia triticina (Pt) that cause stripe and leaf rust, respectively.

UDP-glucosyltransferase HvUGT13248 confers type II resistance to Fusarium graminearum in barley.

Fusarium head blight (FHB) of barley (Hordeum vulgare) causes yield losses and accumulation of trichothecene mycotoxins (e.g. deoxynivalenol [DON]) in grains.

Measuring Pectin Properties to Track Cell Wall Alterations During Plant-Pathogen Interactions.

Plant cell walls act both as a barrier to pathogen entry and as a source of signaling molecules that can modulate plant immunity. Cell walls consist mainly of three polymeric sugars: cellulose, pectin, and hemicellulose (Mohnen et al., Biomass Recalcitrance: deconstructing the plant cell wall for bioenergy, 2008).

Different Modes of Negative Regulation of Plant Immunity by Calmodulin-Related Genes.

Plant immune responses activated through the perception of microbe-associated molecular patterns, leading to pattern-triggered immunity, are tightly regulated. This results in low immune responses in the absence of pathogens and a rapid return to the resting state following an activation event. Here, we show that two genes, and , negatively regulate salicylic acid accumulation and immunity in Arabidopsis ().

WRKY70 prevents axenic activation of plant immunity by direct repression of SARD1.

SARD1 is an activator of plant immunity that promotes production of the hormone salicylic acid (SA) and activation of defense gene expression. SARD1 itself is strongly inducible by infection. Here, we investigated the transcriptional control of SARD1.

[Pyostomatitis vegetans. Numerous pale yellow dots on inflammatory red ground - A case report.].

Pyostomatitis vegetans is a disease of the gingiva and the oral mucosa with noticeable, uncommon morphology. Clinical characteristics of this rare disease and considerations regarding differential diagnosis are described. Pyostomatitis vegetans is frequently associated with chronic inflammatory bowel diseases and can, thus, give a diagnostic hint at an existing ulcerative colitis or Crohn’s disease.

Pectin Biosynthesis Is Critical for Cell Wall Integrity and Immunity in Arabidopsis thaliana.

Plant cell walls are important barriers against microbial pathogens. Cell walls of Arabidopsis thaliana leaves contain three major types of polysaccharides: cellulose, various hemicelluloses, and pectins. UDP-D-galacturonic acid, the key building block of pectins, is produced from the precursor UDP-D-glucuronic acid by the action of glucuronate 4-epimerases (GAEs).

The receptor-like cytoplasmic kinase PCRK1 contributes to pattern-triggered immunity against Pseudomonas syringae in Arabidopsis thaliana.

In this paper we describe PATTERN-TRIGGERED IMMUNITY (PTI) COMPROMISED RECEPTOR-LIKE CYTOPLASMIC KINASE 1 (PCRK1) of Arabidopsis thaliana, an RLCK that is important for defense against the pathogen Pseudomonas syringae pv. maculicola ES4326 (Pma ES4326). We examined defense responses such as bacterial growth, production of reactive oxygen species (ROS) and callose deposition in pcrk1 mutant plants to determine the role of PCRK1 during pathogen infection.

The mRNA decay factor PAT1 functions in a pathway including MAP kinase 4 and immune receptor SUMM2.

Multi-layered defense responses are activated in plants upon recognition of invading pathogens. Transmembrane receptors recognize conserved pathogen-associated molecular patterns (PAMPs) and activate MAP kinase cascades, which regulate changes in gene expression to produce appropriate immune responses. For example, Arabidopsis MAP kinase 4 (MPK4) regulates the expression of a subset of defense genes via at least one WRKY transcription factor.

The Arabidopsis thaliana mitogen-activated protein kinases MPK3 and MPK6 target a subclass of 'VQ-motif'-containing proteins to regulate immune responses.

Mitogen-activated protein kinase (MAPK) cascades play key roles in plant immune signalling, and elucidating their regulatory functions requires the identification of the pathway-specific substrates. We used yeast two-hybrid interaction screens, in vitro kinase assays and mass spectrometry-based phosphosite mapping to study a family of MAPK substrates. Site-directed mutagenesis and promoter-reporter fusion studies were performed to evaluate the impact of substrate phosphorylation on downstream signalling.

Arabidopsis PECTIN METHYLESTERASEs contribute to immunity against Pseudomonas syringae.

Pectins, major components of dicot cell walls, are synthesized in a heavily methylesterified form in the Golgi and are partially deesterified by pectin methylesterases (PMEs) upon export to the cell wall. PME activity is important for the virulence of the necrotrophic fungal pathogen Botrytis cinerea. Here, the roles of Arabidopsis PMEs in pattern-triggered immunity and immune responses to the necrotrophic fungus Alternaria brassicicola and the bacterial hemibiotroph Pseudomonas syringae pv maculicola ES4326 (Pma ES4326) were studied.

Dual regulation of gene expression mediated by extended MAPK activation and salicylic acid contributes to robust innate immunity in Arabidopsis thaliana.

Network robustness is a crucial property of the plant immune signaling network because pathogens are under a strong selection pressure to perturb plant network components to dampen plant immune responses. Nevertheless, modulation of network robustness is an area of network biology that has rarely been explored. While two modes of plant immunity, Effector-Triggered Immunity (ETI) and Pattern-Triggered Immunity (PTI), extensively share signaling machinery, the network output is much more robust against perturbations during ETI than PTI, suggesting modulation of network robustness.

The CALMODULIN-BINDING PROTEIN60 family includes both negative and positive regulators of plant immunity.

Two members of the eight-member CALMODULIN-BINDING PROTEIN60 (CBP60) gene family, CBP60g and SYSTEMIC ACQUIRED RESISTANCE DEFICIENT1 (SARD1), encode positive regulators of plant immunity that promote the production of salicylic acid (SA) and affect the expression of SA-dependent and SA-independent defense genes. Here, we investigated the other six family members in Arabidopsis (Arabidopsis thaliana). Only cbp60a mutations affected growth of the bacterial pathogen Pseudomonas syringae pv maculicola ES4326.

Pattern-triggered immunity suppresses programmed cell death triggered by fumonisin b1.

Programmed cell death (PCD) is a crucial process for plant innate immunity and development. In plant innate immunity, PCD is believed to prevent the spread of pathogens from the infection site. Although proper control of PCD is important for plant fitness, we have limited understanding of the molecular mechanisms regulating plant PCD.

Metabolite profiling of Arabidopsis inoculated with Alternaria brassicicola reveals that ascorbate reduces disease severity.

The interaction between the pathogenic ascomycete Alternaria brassicicola and Arabidopsis was investigated by metabolite profiling. The effect of A. brassicicola challenge on metabolite levels was substantial, with nearly 50% of detected compounds undergoing significant changes.

MPK11-a fourth elicitor-responsive mitogen-activated protein kinase in Arabidopsis thaliana.

Recognition of pathogen attack or elicitation with pathogen-associated molecular patterns (PAMPs) leads to defense signaling that includes activation of the three mitogen-activated protein kinases (MPKs), MPK3, MPK4 and MPK6 in Arabidopsis. Recently, we demonstrated the activation of a fourth MPK, MPK11, after treatment with flg22, a 22 amino acid PAMP derived from bacterial flagellin. Here, we extended the study by examining elicitation with two other PAMPs, elf18 (derived from bacterial elongation factor EF-Tu) and ch8 (N-acetylchitooctaose derived from fungal chitin).

Activation of the Arabidopsis thaliana mitogen-activated protein kinase MPK11 by the flagellin-derived elicitor peptide, flg22.

Mitogen-activated protein kinases (MAPK) mediate cellular signal transduction during stress responses, as well as diverse growth and developmental processes in eukaryotes. Pathogen infection or treatments with conserved pathogen-associated molecular patterns (PAMPs) such as the bacterial flagellin-derived flg22 peptide are known to activate three Arabidopsis thaliana MAPK: MPK3, MPK4, and MPK6. Several stresses, including flg22 treatment, are known to increase MPK11 expression but activation of MPK11 has not been shown.

An efficient Agrobacterium-mediated transient transformation of Arabidopsis.

Agrobacterium tumefaciens-mediated transient transformation has been a useful procedure for characterization of proteins and their functions in plants, including analysis of protein-protein interactions. Agrobacterium-mediated transient transformation of Nicotiana benthamiana by leaf infiltration has been widely used due to its ease and high efficiency. However, in Arabidopsis this procedure has been challenging.

The Arabidopsis mitogen-activated protein kinase phosphatase PP2C5 affects seed germination, stomatal aperture, and abscisic acid-inducible gene expression.

Abscisic acid (ABA) is an important phytohormone regulating various cellular processes in plants, including stomatal opening and seed germination. Although protein phosphorylation via mitogen-activated protein kinases (MAPKs) has been suggested to be important in ABA signaling, the corresponding phosphatases are largely unknown. Here, we show that a member of the Protein Phosphatase 2C (PP2C) family in Arabidopsis (Arabidopsis thaliana), PP2C5, is acting as a MAPK phosphatase.

Ethylene signalling and ethylene-targeted transcription factors are required to balance beneficial and nonbeneficial traits in the symbiosis between the endophytic fungus Piriformospora indica and Arabidopsis thaliana.

*The endophytic fungus Piriformospora indica colonizes the roots of the model plant Arabidopsis thaliana and promotes its growth and seed production. The fungus can be cultivated in axenic culture without a host, and therefore this is an excellent system to investigate plant-fungus symbiosis. *The growth of etr1, ein2 and ein3/eil1 mutant plants was not promoted or even inhibited by the fungus; the plants produced less seeds and the roots were more colonized compared with the wild-type.

A protein phosphatase 2C, responsive to the bacterial effector AvrRpm1 but not to the AvrB effector, regulates defense responses in Arabidopsis.

Using a proteomics approach, a PP2C-type phosphatase (renamed PIA1, for PP2C induced by AvrRpm1) was identified that accumulates following infection by Pseudomonas syringae expressing the type III effector AvrRpm1, and subsequent activation of the corresponding plant NB-LRR disease resistance protein RPM1. No accumulation of PIA1 protein was seen following infection with P. syringae expressing AvrB, another type III effector that also activates RPM1, although PIA transcripts were observed.

Sometimes new results raise new questions: the question marks between mitogen-activated protein kinase and ethylene signaling.

In Arabidopsis thaliana, mitogen activated protein kinase (MAPK) signaling cascades that contain MPK3, MPK4 and MPK6 have been implicated in various aspects of developmental processes and stress responses. We identified an ethylene response factor (ERF104), which controls innate immunity, to be a specific substrate of MPK6 and showed that ethylene signaling regulates the release of the ERF104 substrate from its kinase. Implications and questions that arise from our findings are addressed.

Flg22 regulates the release of an ethylene response factor substrate from MAP kinase 6 in Arabidopsis thaliana via ethylene signaling.

Mitogen-activated protein kinase (MAPK)-mediated responses are in part regulated by the repertoire of MAPK substrates, which is still poorly elucidated in plants. Here, the in vivo enzyme-substrate interaction of the Arabidopsis thaliana MAP kinase, MPK6, with an ethylene response factor (ERF104) is shown by fluorescence resonance energy transfer. The interaction was rapidly lost in response to flagellin-derived flg22 peptide.

[Assessment of severity of oral lichen planus using a new clinical index].

Aim: The goal of this study was to develop a clinical index to assess therapy of oral lichen planus (OLP) to be used in comparing the efficacy of two topical glucocorticoids. The clinical severity of non-gingival and gingival lichen planus and their severity from the patients' view were evaluated.

Description Of The Index: A clinical index for assessing the severity of oral lichen planus is described with which the clinical forms as well as all the varying combinations of forms can be addressed separately.

Focal palmoplantar and gingival keratosis: a distinct palmoplantar ectodermal dysplasia with epidermolytic alterations but lack of mutations in known keratins.

Focal palmoplantar and gingival keratosis is a rare autosomal dominant disease whose clinical features, and in particular, pathologic alterations and molecular etiology remain to be well defined. Recently we observed a German family affected by the disease in at least 3 consecutive generations. The 4 patients examined showed circumscribed and painful hyperkeratosis at the weight-bearing plantar skin since infancy, rather mild palmar hyperkeratosis, and continuous leukokeratosis confined to the maxillary and mandibulary attached gingiva.