Barley ADH-1 modulates susceptibility to Bgh and is involved in chitin-induced systemic resistance.

The plant primary energy metabolism is profoundly reorganized under biotic stress conditions and there is increasing evidence for a role of the fermentative pathway in biotic interactions. Previously we showed via transient gene silencing or overexpression a function of barley alcohol dehydrogenase 1 (HvADH-1) in the interaction of barley with the parasitic fungus Blumeria graminis f.sp.

Silencing of RBOHF2 Causes Leaf Age-Dependent Accelerated Senescence, Salicylic Acid Accumulation, and Powdery Mildew Resistance in Barley.

Plant RBOH (RESPIRATORY BURST OXIDASE HOMOLOGS)-type NADPH oxidases produce superoxide radical anions and have a function in developmental processes and in response to environmental challenges. Barley RBOHF2 has diverse reported functions in interaction with the biotrophic powdery mildew fungus Blumeria graminis f. sp.

Cell-wall invertases, key enzymes in the modulation of plant metabolism during defence responses.

Most plant-pathogen interactions do not result in pathogenesis because of pre-formed defensive plant barriers or pathogen-triggered activation of effective plant immune responses. The mounting of defence reactions is accompanied by a profound modulation of plant metabolism. Common metabolic changes are the repression of photosynthesis, the increase in heterotrophic metabolism and the synthesis of secondary metabolites.

Cyanobacterial phytochrome2 regulates the heterotrophic metabolism and has a function in the heat and high-light stress response.

Cyanobacteria combine the photosynthetic and respiratory electron transport in one membrane system, the thylakoid membrane. This feature requires an elaborate regulation mechanism to maintain a certain redox status of the electron transport chain, hence allowing proper photosynthetic and respiratory energy metabolism. In this context, metabolic adaptations, as seen in the light-to-dark and dark-to-light transitions, are particularly challenging.

Infection of barley with the parasitic fungus Blumeria graminis f.sp. hordei results in the induction of HvADH1 and HvADH2.

Besides the established functions of alcohol dehydrogenase (ADH) in the flooding response and in seed and pollen metabolism there is increasing evidence for a role of the fermentative pathway in biotic interactions. We have recently shown that barley ADH may be involved in susceptibility to the parasitic fungus Blumeria graminis f.sp.

Alcohol dehydrogenase 1 of barley modulates susceptibility to the parasitic fungus Blumeria graminis f.sp. hordei.

Plant primary energy metabolism is profoundly reorganized under biotic stress conditions and there is increasing evidence for a role for the fermentative pathway in biotic interactions. However, the mechanisms regulating metabolic reprogramming are not well understood despite its critical function in the biotic stress response. Here the function of alcohol dehydrogenase (ADH) in the interaction of barley with the parasitic fungus Blumeria graminis f.

RBOHF2 of barley is required for normal development of penetration resistance to the parasitic fungus Blumeria graminis f. sp. hordei.

Plant respiratory burst oxidase homologs are prominent sources of reactive oxygen species (ROS) in signal transduction and in interaction with microbes. However, the function of respiratory burst oxidase homologue (RBOH) genes in interaction with microbes might differ for certain plant and pathogen species. We produced transgenic barley knock down (KD) for the HvRBOHF2 isoform of NADPH oxidases.

Extracellular invertase LIN6 of tomato: a pivotal enzyme for integration of metabolic, hormonal, and stress signals is regulated by a diurnal rhythm.

To elucidate the regulation pattern of extracellular invertase LIN6 of tomato, the corresponding promoter has been cloned and the sink-tissue specific expression and its regulation by sugars, stress stimuli, growth regulators, and the diurnal rhythm is shown. The in situ analysis of transgenic tobacco plants expressing a LIN6 promoter::beta-glucuronidase reporter gene fusion demonstrates LIN6 expression in sink tissues, such as pollen grains and vascular tissues of leaves and stems. LIN6 is up-regulated in close proximity to wounded tissue, and by methyl jasmonate and abscisic acid, global signals known to modulate defence/stress response.

Cloning and characterization of a novel LpWRKY1 transcription factor in tomato.

The initiation of defence responses in plants is accompanied by fundamental changes in gene expression: the expression of pathogenesis-related genes is co-ordinately regulated with metabolic changes such as down regulation of photosynthesis and induction of sink metabolism. To identify candidate regulators of this co-ordinated regulatory mechanism, the role of WRKY transcription factors in the initiation of defence response was analysed in tomato. A WRKY-type transcription factor (LpWRKY1) from tomato was cloned by a reverse Northern approach.

Gibberellin-dependent induction of tomato extracellular invertase Lin7 is required for pollen development.

The tomato extracellular invertase family comprises four members with different expression patterns. Among the three invertase isoenzymes expressed in floral tissues, Lin5, Lin6 and Lin7, the expression of Lin7 was previously shown to be restricted to the tapetum and pollen. Histochemical analysis of β-glucuronidase (GUS) reporter activity shows Lin7 expression in pollen and pollen tubes of corresponding transgenic plants.

Cloning of a CACTA transposon-like insertion in intron I of tomato invertase Lin5 gene and identification of transposase-like sequences of Solanaceae species.

Very few CACTA transposon-like sequences have been described in Solanaceae species. Sequence information has been restricted to partial transposase (TPase)-like fragments, and no target gene of CACTA-like transposon insertion has been described in tomato to date. In this manuscript, we report on a CACTA transposon-like insertion in intron I of tomato (Lycopersicon esculentum) invertase gene Lin5 and TPase-like sequences of several Solanaceae species.

A heat-activated MAP kinase in tomato: a possible regulator of the heat stress response.

Adaptation to elevated temperatures is of major importance for the survival of plants. The role of kinases in heat stress response was studied in tomato by in gel and in solution kinase assays using myelin basic protein as substrate. The application of heat stress in a naturally occurring temperature range resulted in a fast and transient activation of a 50 kDa mitogen-activated protein (MAP) kinase both in a photoautotrophic cell suspension culture and in leaves of mature plants.