An RLP23-SOBIR1-BAK1 complex mediates NLP-triggered immunity.

Plants and animals employ innate immune systems to cope with microbial infection. Pattern-triggered immunity relies on the recognition of microbe-derived patterns by pattern recognition receptors (PRRs). Necrosis and ethylene-inducing peptide 1-like proteins (NLPs) constitute plant immunogenic patterns that are unique, as these proteins are produced by multiple prokaryotic (bacterial) and eukaryotic (fungal, oomycete) species.

A conserved peptide pattern from a widespread microbial virulence factor triggers pattern-induced immunity in Arabidopsis.

Microbe- or host damage-derived patterns mediate activation of pattern-triggered immunity (PTI) in plants. Microbial virulence factor (effector)-triggered immunity (ETI) constitutes a second layer of plant protection against microbial attack. Various necrosis and ethylene-inducing peptide 1 (Nep1)-like proteins (NLPs) produced by bacterial, oomycete and fungal microbes are phytotoxic virulence factors that exert immunogenic activities through phytotoxin-induced host cell damage.

Receptor like proteins associate with SOBIR1-type of adaptors to form bimolecular receptor kinases.

Receptor like proteins (RLPs) build large protein families in all higher plants. Apart from RLPs with conserved roles in development, an increasing number of RLPs could be associated with functions as immunoreceptors detecting specific patterns from a variety of pathogens. Recent work showed that functionality of these RLPs, at least those with leucine rich repeats in their extracellular domain, depends on association with the common adaptor kinase SOBIR1.

Immune receptor complexes at the plant cell surface.

Immunity to microbial infection is a common feature of metazoans and plants. Plants employ plasma membrane and cytoplasmic receptor systems for sensing microbe-derived or host-derived patterns and effectors and to trigger inducible immune defenses. Different biochemical types of plasma membrane immune receptors mediate recognition predominantly of peptide and carbohydrate patterns.

bZIPs and WRKYs: two large transcription factor families executing two different functional strategies.

bZIPs and WRKYs are two important plant transcription factor (TF) families regulating diverse developmental and stress-related processes. Since a partial overlap in these biological processes is obvious, it can be speculated that they fulfill non-redundant functions in a complex regulatory network. Here, we focus on the regulatory mechanisms that are so far described for bZIPs and WRKYs.

Prerequisites, performance and profits of transcriptional profiling the abiotic stress response.

During the last decade, microarrays became a routine tool for the analysis of transcripts in the model plant Arabidopsis thaliana and the crop plant species rice, poplar or barley. The overwhelming amount of data generated by gene expression studies is a valuable resource for every scientist. Here, we summarize the most important findings about the abiotic stress responses in plants.

Alanine zipper-like coiled-coil domains are necessary for homotypic dimerization of plant GAGA-factors in the nucleus and nucleolus.

GAGA-motif binding proteins control transcriptional activation or repression of homeotic genes. Interestingly, there are no sequence similarities between animal and plant proteins. Plant BBR/BPC-proteins can be classified into two distinct groups: Previous studies have elaborated on group I members only and so little is known about group II proteins.

Biotechnological concepts for improving plant innate immunity.

Saving the world's food supply constitutes one of the major challenges of the future. As a complement to classical and molecular breeding technologies, novel strategies for biotechnological improvement of plant immunity aim at enhancing host recognition capacities for potential pathogens, at boosting the executive arsenal of plant immunity, and at interfering with virulence strategies employed by microbial pathogens. In addition, chemical and biological priming provides means for triggering plant defenses in a non-transgenic manner.

Transparent Testa Glabra 1 (TTG1) and TTG1-like genes in Matthiola incana R. Br. and related Brassicaceae and mutation in the WD-40 motif.

TTG1 (Transparent Testa Glabra 1), a WD-40 repeat protein, is involved in regulation of flavonoid/anthocyanin biosynthesis, seed coat (mucilage) development/pigmentation and trichome formation in leaves. Here, we characterized the TTG1 gene of Matthiola incana wild type (e locus), showing 85.3% similarity to TTG1 of A.

Organization, differential expression and methylation of rDNA in artificial Solanum allopolyploids.

Uniparental activity of ribosomal RNA genes (rDNA) in interspecific hybrids is known as nucleolar dominance (ND). To see if difference in rDNA intergenic spacers (IGS) might be correlated with ND, we have used artificial Solanum allopolyploids and back-crossed lines. Combining fluorescence in situ hybridization and quantification of the level of the rRNA precursor by real-time PCR, we demonstrated that an expression hierarchy exists: In leaves, roots, and petals of the respective allopolyploids, rDNA of S lycopersicum (tomato) dominates over rDNA of S.

Characterization and structural features of a chalcone synthase mutation in a white-flowering line of Matthiola incana R. Br. (Brassicaceae).

For Matthiola incana (Brassicaceae), used as a model system to study biochemical and genetical aspects of anthocyanin biosynthesis, several nearly isogenic colored wild type lines and white-flowering mutant lines are available, each with a specific defect in the genes responsible for anthocyanin production (genes e, f, and g). For gene f supposed to code for chalcone synthase (CHS; EC 2.3.

Molecular evolution of rDNA external transcribed spacer and phylogeny of sect. Petota (genus Solanum).

The 5(') external transcribed spacer (ETS) region of ribosomal DNA of 30 species of Solanum sect. Petota and the European Solanum dulcamara were compared. Two structural elements can be distinguished in the ETS: (i).

Cloning and expression of two novel aldo-keto reductases from Digitalis purpurea leaves.

The aldo-keto reductase (AKR) superfamily comprises proteins that catalyse mainly the reduction of carbonyl groups or carbon-carbon double bonds of a wide variety of substrates including steroids. Such types of reactions have been proposed to occur in the biosynthetic pathway of the cardiac glycosides produced by Digitalis plants. Two cDNAs encoding leaf-specific AKR proteins (DpAR1 and DpAR2) were isolated from a D.

Heat stress- and heat shock transcription factor-dependent expression and activity of ascorbate peroxidase in Arabidopsis.

To find evidence for a connection between heat stress response, oxidative stress, and common stress tolerance, we studied the effects of elevated growth temperatures and heat stress on the activity and expression of ascorbate peroxidase (APX). We compared wild-type Arabidopsis with transgenic plants overexpressing heat shock transcription factor 3 (HSF3), which synthesize heat shock proteins and are improved in basal thermotolerance. Following heat stress, APX activity was positively affected in transgenic plants and correlated with a new thermostable isoform, APX(S).