A5061923494- Plant-Microbe Interactions and Immunity
- Plant nutrient uptake and metabolism
- Plant Pathogenic Bacteria Studies
- Plant Molecular Biology Research
- Photosynthetic Processes and Mechanisms
- Plant Parasitism and Resistance
- Plant Stress Responses and Tolerance
- Plant tissue culture and regeneration
- Potato Plant Research
- Microbial Metabolites in Food Biotechnology
- Legume Nitrogen Fixing Symbiosis
- Plant Virus Research Studies
- Plant Micronutrient Interactions and Effects
- Plant pathogens and resistance mechanisms
- Genomics, phytochemicals, and oxidative stress
- Enzyme Production and Characterization
- Plant Reproductive Biology
- Enzyme Structure and Function
- Moringa oleifera research and applications
- Redox biology and oxidative stress
- Biofuel production and bioconversion
- Lipid metabolism and biosynthesis
- Endoplasmic Reticulum Stress and Disease
- Ubiquitin and proteasome pathways
- Plant Gene Expression Analysis
University of Potsdam
2014-2024
Leibniz Institute of Vegetable and Ornamental Crops
2014-2024
Friedrich-Alexander-Universität Erlangen-Nürnberg
2007-2015
Leibniz Association
2002-2014
Leibniz Institute of Plant Genetics and Crop Plant Research
2002-2011
Max Planck Institute of Molecular Plant Physiology
2011
Leibniz Institute for Neurobiology
2001-2007
Abstract Here, we characterize a plastidial thioredoxin (TRX) isoform from Arabidopsis thaliana that defines previously unknown branch of TRXs lying between x- and y-type thus was named TRX z. An knockout mutant z had severe albino phenotype inhibited in chloroplast development. Quantitative real-time RT-PCR analysis the suggested expressions genes depend on plastid-encoded RNA polymerase (PEP) were specifically decreased. Similar results obtained upon virus-induced gene silencing (VIGS)...
Abstract Since years, research on SnRK1, the major cellular energy sensor in plants, has tried to define its role signalling. However, these attempts were notoriously hampered by lethality of a complete knockout SnRK1. Therefore, we generated an inducible amiRNA::SnRK1α2 snrk1α1 knock out background ( / α2 ) abolish SnRK1 activity understand systemic functions signalling under deprivation triggered extended night treatment. We analysed vivo phosphoproteome, proteome and metabolome found that...
The eukaryotic cytoskeleton is essential for structural support and intracellular transport, therefore a common target of animal pathogens. However, no phytopathogenic effector has yet been demonstrated to specifically the plant cytoskeleton. Here we show that Pseudomonas syringae type III secreted HopZ1a interacts with tubulin polymerized microtubules. We demonstrate an acetyltransferase activated by co-factor phytic acid. Activated acetylates itself tubulin. conserved autoacetylation site...
Abstract Trehalose-6-phosphate (T6P) is a signaling metabolite that regulates carbon metabolism, developmental processes, and growth in plants. In Arabidopsis (Arabidopsis thaliana), T6P is, at least part, mediated through inhibition of the SNF1-related protein kinase SnRK1. To investigate role heterotrophic, starch-accumulating storage organ, transgenic potato (Solanum tuberosum) plants with altered levels specifically their tubers were generated. Transgenic lines elevated (B33-TPS,...
Abstract Little is known about the function of host factors involved in disease susceptibility. The barley (Hordeum vulgare) ROP (RHO plants) G-protein RACB required for full susceptibility leaf epidermis to invasion by biotrophic fungus Blumeria graminis f. sp hordei. Stable transgenic knockdown reduced ability accommodate haustoria B. intact epidermal cells and form hairs on root epidermis, suggesting that a common element hair outgrowth ingrowth cells. We further identified...
The phytopathogenic bacterium Xanthomonas campestris pv. vesicatoria (Xcv) requires type III effector proteins (T3Es) for virulence. After translocation into the host cell, T3Es are thought to interact with components of immunity suppress defence responses. XopJ is a T3E protein from Xcv that interferes plant immune responses; however, its cellular target unknown. Here we show interacts proteasomal subunit RPT6 in yeast and planta inhibit proteasome activity. A C235A mutation within...
Recent evidence suggests that the ubiquitin-proteasome system is involved in several aspects of plant immunity and a range pathogens subvert to enhance their virulence. Here, we show proteasome activity strongly induced during basal defense Arabidopsis (Arabidopsis thaliana). Mutant lines subunits RPT2a RPN12a support increased bacterial growth virulent Pseudomonas syringae pv tomato DC3000 (Pst) maculicola ES4326. Both are required for pathogen-associated molecular pattern-triggered...
Beyond its role in cellular homeostasis, autophagy plays anti- and promicrobial roles host-microbe interactions, both animals plants. One prominent of antimicrobial is to degrade intracellular pathogens or microbial molecules, a process termed xenophagy. Consequently, microbes evolved mechanisms hijack modulate escape elimination. Although well-described animals, the extent which xenophagy contributes plant-bacteria interactions remains unknown. Here, we provide evidence that Xanthomonas...
As a critical part of plant immunity, cells that are attacked by pathogens undergo rapid transcriptional reprogramming to minimize virulence. Many bacterial phytopathogens use type III effector (T3E) proteins interfere with defense responses, including this reprogramming. Here, we show Xanthomonas outer protein S (XopS), T3E campestris pv. vesicatoria (Xcv), interacts and inhibits proteasomal degradation WRKY40, regulator gene expression. Virus-induced silencing WRKY40 in pepper (Capsicum...
ABSTRACT The capsid protein (CP) of potyviruses is required for various steps during plant infection, such as virion assembly, cell-to-cell movement, and long-distance transport. This suggests a series compatible interactions with putative host factors which, however, are largely unknown. By using the yeast two-hybrid system CP from Potato virus Y (PVY) was found to interact novel subset DnaJ-like proteins tobacco, designated NtCPIPs. Mutational analysis identified core region, previously...
In plants, SNF1-related kinase (SnRK1) responds to the availability of carbohydrates as well environmental stresses by down-regulating ATP consuming biosynthetic processes, while stimulating energy-generating catabolic reactions through gene expression and post-transcriptional regulation. The functional SnRK1 complex is a heterotrimer where catalytic α subunit associates with regulatory β an activating γ subunit. Several different metabolites hormone abscisic acid (ABA) have been shown...
In plants, the sucrose non-fermenting (SNF1)-related protein kinase 1 (SnRK1) represents a central integrator of low energy signaling and acclimation towards many environmental stress responses. Although SnRK1 acts as convergent point for different metabolic signals to control growth development, it is currently unknown how these could be translated into cell-type or stimulus specific response since components SnRK1-regulated pathways remain unidentified. Recently, we have demonstrated that...
To change the hexose-to-sucrose ratio within phloem cells, yeast-derived cytosolic invertase was expressed in transgenic potato (Solanum tuberosum cv. Desirée) plants under control of rolC promoter. Vascular tissue specific expression transgene verified by histochemical detection activity tuber cross-sections. Vegetative growth and yield unaltered as compared to wild-type plants. However, sprout stored tubers much delayed, indicating impaired phloem-transport sucrose towards developing bud....
Downregulation of endogenous genes via post-transcriptional gene silencing (PTGS) is a key to the characterization function in plants. The recent discovery that double-stranded RNA (dsRNA) an extremely effective trigger greatly enhanced predictability this approach. However, strong constitutive often leads pleiotropic effects, which make it difficult directly relate phenotype function, or even interferes with recovery viable transgenic Here, we show genetic interference can be achieved...
Application of norflurazon (NF) damages plastids, induces photobleaching and represses expression the nuclear LHCB1.2 gene encoding a light-harvesting protein. In genomes uncoupled (gun) mutants, is maintained in presence NF. The mutants gun2, gun4 gun5 exhibit perturbations tetrapyrrole biosynthesis, but gun1 defective organellar (OGE). How gun mutations affect (NGE) why signals elicited by two types evoke same response remains unknown. Here we show that carotenoid biosynthesis inhibitors...
In plants, the shikimate pathway occurs in plastid and leads to biosynthesis of aromatic amino acids. The bifunctional 3-dehydroquinate dehydratase/shikimate dehydrogenase (DHD/SHD) catalyses conversion dehydroquinate into shikimate. Expression NtDHD/SHD was suppressed by RNAi transgenic tobacco plants. Transgenic lines with <40% wild-type activity displayed severe growth retardation reduced content acids downstream products such as cholorogenic acid lignin. Dehydroquinate, substrate enzyme,...
During photosynthesis, triose-phosphates (trioseP) exported from the chloroplast to cytosol are converted sucrose via cytosolic fructose-1,6-bisphosphatase (cFBPase). Expression analysis in rice suggests that OscFBP1 plays a major role conversion of trioseP leaves during day. The isolated mutants exhibited markedly decreased photosynthetic rates and severe growth retardation with reduced chlorophyll content, which results plant death. Analysis primary carbon metabolites revealed both...
Sucrose (Suc)-phosphate synthase (SPS) catalyses one of the rate-limiting steps in synthesis Suc plants. The Arabidopsis genome contains four annotated SPS genes which can be grouped into three different families (SPSA1, SPSA2, SPSB, and SPSC). However, functional significance this multiplicity is as yet only poorly understood. All isoforms show enzymatic activity when expressed yeast although there variation sensitivity towards allosteric effectors. Promoter–reporter gene analyses...
The YopJ family of type III effector proteins (T3E) is one the largest and most widely distributed families proteins, whose members are highly diversified in virulence functions. In present study, HopZ4, a member T3E from cucumber pathogen Pseudomonas syringae pv. lachrymans described. HopZ4 shares high sequence similarity with Xanthomonas XopJ, functional analysis suggests conserved function between these two T3E. As has previously been shown for interacts proteasomal subunit RPT6 yeast...
Many animal and plant pathogenic bacteria inject type III effector (T3E) proteins into their eukaryotic host cells to suppress immunity. The Yersinia outer protein J (YopJ) family of T3Es is a widely distributed found in both pathogens, its members are highly diversified virulence functions. Some have been shown possess acetyltransferase activity; however, whether this general feature YopJ currently unknown. T3E Xanthomonas (XopJ), from the pathogen campestris pv vesicatoria, interacts with...
Abstract Sucrose (Suc)-phosphate synthase (SPS) plays a crucial role in the synthesis of Suc photosynthetic and nonphotosynthetic tissues. Several isoforms SPS exist dicotyledonous plants that can be grouped into different families A, B, C. To explore whether functional differences between gene might exist, we characterized representative for each family from tobacco (Nicotiana tabacum). RNA-blot analysis revealed distinct expression pattern three genes. While A-family member (NtSPSA) was...
Abstract Background Maize is a major crop plant, grown for human and animal nutrition, as well renewable resource bioenergy. When looking at the problems of limited fossil fuels, growth world’s population or climate change, it important to find ways increase yield biomass maize study how reacts specific abiotic biotic stress situations. Within OPTIMAS systems biology project plants were under large set controlled conditions, phenotypically characterised plant material was harvested analyse...
Redox modulation of protein activity by thioredoxins (TRXs) plays a key role in cellular regulation. Thioredoxin z (TRX z) and its interaction partner fructokinase-like 1 (FLN1) represent subunits the plastid-encoded RNA polymerase (PEP), suggesting both proteins redox regulation chloroplast gene expression. Loss TRX or FLN1 expression generates PEP-deficient phenotype renders plants incapable to grow autotrophically. This study shows that PEP function trx fln1 can be restored...