Konfokales Laserscanning-Mikroskop
Final Report Abstract
Our work is focussed on structural and functional aspects of the plant cytoskeleton and endomembrane system in the context of cell differentiation, organ development and response to environmental signals including stress. We are studying these phenomena in wild type and mutant plant of several higher plant species and “primitive” plant unicells such as the green alga Acetabularia and several diatom species. We are using microscopic imaging techniques on fixed and live specimens employing in-vivo fluorochromes, antibodies and GFP-reporter constructs as tools for the visualization of these components and compartments. Of particular importance is the recycling of endomembranes at the level of the plasma membrane and the state of the endosomal compartment as a central cell component in these processes. Important molecular players in these processes are studied in detail, such as synaptotagmin, clathrin-adaptor proteins 1, 2 and 4, stonin-like protein and a novel receptor-like protein kinases involved in cell polarity. Another focus of our work is gravitropism and the involvement of trans-cellular auxin transport and the particular involvement of membrane recycling processes, cytoskeletal dynamics and myosin motor functions at the polar cross walls in the transition zone of roots and in root hairs. A further research topic in our lab addresses the reaction of cells on the level of the cytoskeleton and the state of endomembrane recycling involving second messengers such as reactive oxygen species acting under normal conditions and in stress situations such as osmotic stress and mechanical pressure. A new area of research that we are just developing in our lab, is concerned with the dynamics of the cytoskeleton and endomembrane system in the unicellular diatoms. These are unique cells, forming a nanostructured silica shell around them in the course of cell division. This is an intricate process, which has not yet been studied in detail on the level of the cytoskeleton, particularly not in live cells employing fluorescent reporter proteins.
Publications
- (2010) Structural sterols are involved in both the initiation and tip growth of root hairs in Arabidopsis thaliana. Plant Cell. 22(9): 2999-3019. (2010)
Ovecka M., Berson T., Beck M., Derksen J., Šamaj J., Baluška F., Lichtscheidl I.K.
- Arabidopsis homologs of Nucleus- and Phragmoplast-Localized Kinase 2 and 3 and Mitogen-Activated Protein Kinase 4 are essential for microtubule organization. Plant Cell 22(3): 755-771. (2010)
Beck M., Komis G., Müller J., Menzel D., Šamaj J.
- Arabidopsis MPK6 is involved in cell division plane control during early root development, and localizes to the pre-prophase band, phragmoplast, trans-Golgi network and plasma membrane. Plant J. 61(2): 234–248. (2010)
Müller J., Beck M., Mettbach U., Komis G., Hause G., Menzel D., Šamaj J.
- Mitogen-activated protein kinase 4 is involved in the regulation of mitotic and cytokinetic microtubule transitions in Arabidopsis thaliana. New Phytologist 189: 1069–1083. (2011)
Beck, M., Komis, G., Ziemann, A., Menzel, D., Šamaj, J.
