Unser 10. Leibniz Plant Biochemistry Symposium am 7. und 8. Mai war ein großer Erfolg. Thematisch ging es in diesem Jahr um neue Methoden und Forschungsansätze der Naturstoffchemie. Die exzellenten Vorträge über Wirkstoffe…
Omanische Heilpflanze im Fokus der Phytochemie IPB-Wissenschaftler und Partner aus Dhofar haben jüngst die omanische Heilpflanze Terminalia dhofarica unter die phytochemische Lupe genommen. Die Pflanze ist reich an…
Geschmack ist vorhersagbar: Mit FlavorMiner. FlavorMiner heißt das Tool, das IPB-Chemiker und Partner aus Kolumbien jüngst entwickelt haben. Das Programm kann, basierend auf maschinellem Lernen (KI), anhand der…
Dobritzsch, S.; Weyhe, M.; Schubert, R.; Dindas, J.; Hause, G.; Kopka, J.; Hause, B.;Dissection of jasmonate functions in tomato stamen development by transcriptome and metabolome analysesBMC Biol.1328(2015)DOI: 10.1186/s12915-015-0135-3
BackgroundJasmonates are well known plant signaling components required for stress responses and development. A prominent feature of jasmonate biosynthesis or signaling mutants is the loss of fertility. In contrast to the male sterile phenotype of Arabidopsis mutants, the tomato mutant jai1-1 exhibits female sterility with additional severe effects on stamen and pollen development. Its senescence phenotype suggests a function of jasmonates in regulation of processes known to be mediated by ethylene. To test the hypothesis that ethylene involved in tomato stamen development is regulated by jasmonates, a temporal profiling of hormone content, transcriptome and metabolome of tomato stamens was performed using wild type and jai1-1.ResultsWild type stamens showed a transient increase of jasmonates that is absent in jai1-1. Comparative transcriptome analyses revealed a diminished expression of genes involved in pollen nutrition at early developmental stages of jai1-1 stamens, but an enhanced expression of ethylene-related genes at late developmental stages. This finding coincides with an early increase of the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC) in jai1-1 and a premature pollen release from stamens, a phenotype similarly visible in an ethylene overproducing mutant. Application of jasmonates to flowers of transgenic plants affected in jasmonate biosynthesis diminished expression of ethylene-related genes, whereas the double mutant jai1-1 NeverRipe (ethylene insensitive) showed a complementation of jai1-1 phenotype in terms of dehiscence and pollen release.ConclusionsOur data suggest an essential role of jasmonates in the temporal inhibition of ethylene production to prevent premature desiccation of stamens and to ensure proper timing in flower development.
Bücher und Buchkapitel
Hause, B.; Hause, G.;Microscope Techniques and Single Cell AnalysisKrauss, G.-J. & Nies, D. H., eds.366-382(2015)ISBN:9783527686063DOI: 10.1002/9783527686063.ch19
For centuries, progress in biological research has been connected to the development of tools and equipment that allow new insights into the living matter. The invention of and improvements in optical systems were very important because exceeding the limits of the optical resolution of the human eye delivered new insights into tissues, cells, and subcellular compartments on the one hand and cellular processes on the other. Even the very first light microscopes, developed at the beginning of the seventeenth century, enabled the discovery of “Cells as little boxes” by Robert Hooke, and of bacteria by Antoni van Leeuwenhoek. Since then, many aspects of microscopes have been improved and new illumination, staining, and detection methods have been developed in order to increase the optical resolution. In this chapter, we describe the principles and possibilities of the use of microscopes in biology, as well as specific methods of preparing biological materials in order to obtain optimum microscopic images with an appropriate scientific message. Further, emphasis is given on staining techniques used for biological materials including transgenic approaches that use the wide variance of fluorescent proteins.
Publikation
Phan, H. T.; Hause, B.; Hause, G.; Arcalis, E.; Stoger, E.; Maresch, D.; Altmann, F.; Joensuu, J.; Conrad, U.;Influence of Elastin-Like Polypeptide and Hydrophobin on Recombinant Hemagglutinin Accumulations in Transgenic Tobacco PlantsPLOS ONE9e99347(2014)DOI: 10.1371/journal.pone.0099347
Fusion protein strategies are useful tools to enhance expression and to support the development of purification technologies. The capacity of fusion protein strategies to enhance expression was explored in tobacco leaves and seeds. C-terminal fusion of elastin-like polypeptides (ELP) to influenza hemagglutinin under the control of either the constitutive CaMV 35S or the seed-specific USP promoter resulted in increased accumulation in both leaves and seeds compared to the unfused hemagglutinin. The addition of a hydrophobin to the C-terminal end of hemagglutinin did not significantly increase the expression level. We show here that, depending on the target protein, both hydrophobin fusion and ELPylation combined with endoplasmic reticulum (ER) targeting induced protein bodies in leaves as well as in seeds. The N-glycosylation pattern indicated that KDEL sequence-mediated retention of leaf-derived hemagglutinins and hemagglutinin-hydrophobin fusions were not completely retained in the ER. In contrast, hemagglutinin-ELP from leaves contained only the oligomannose form, suggesting complete ER retention. In seeds, ER retention seems to be nearly complete for all three constructs. An easy and scalable purification method for ELPylated proteins using membrane-based inverse transition cycling could be applied to both leaf- and seed-expressed hemagglutinins.
Publikation
Landgraf, R.; Smolka, U.; Altmann, S.; Eschen-Lippold, L.; Senning, M.; Sonnewald, S.; Weigel, B.; Frolova, N.; Strehmel, N.; Hause, G.; Scheel, D.; Böttcher, C.; Rosahl, S.;The ABC Transporter ABCG1 Is Required for Suberin Formation in Potato Tuber PeridermPlant Cell263403-3415(2014)DOI: 10.1105/tpc.114.124776
The lipid biopolymer suberin plays a major role as a barrier both at plant-environment interfaces and in internal tissues, restricting water and nutrient transport. In potato (Solanum tuberosum), tuber integrity is dependent on suberized periderm. Using microarray analyses, we identified ABCG1, encoding an ABC transporter, as a gene responsive to the pathogen-associated molecular pattern Pep-13. Further analyses revealed that ABCG1 is expressed in roots and tuber periderm, as well as in wounded leaves. Transgenic ABCG1-RNAi potato plants with downregulated expression of ABCG1 display major alterations in both root and tuber morphology, whereas the aerial part of the ABCG1-RNAi plants appear normal. The tuber periderm and root exodermis show reduced suberin staining and disorganized cell layers. Metabolite analyses revealed reduction of esterified suberin components and hyperaccumulation of putative suberin precursors in the tuber periderm of RNA interference plants, suggesting that ABCG1 is required for the export of suberin components.