Konfokales Laserscanning-Mikroskop (CLSM)
Final Report Abstract
Subcellular localization behavior of Arabidopsis LysM-domain proteins: In this project we study functionality and subcellular localization patterns of a class of receptor-like kinases and potential interactors that are required for perception of pathogen/microbe associated molecular patterns (P/MAMPs) and activation of the plant’s innate immune defense machinery. Subcellular localization dynamcis of executive nonhost resistance components: In this project we focus on the subcellular behavior of proteins that mediate entry control towards fungal pathogens. In particular we study the subcellular localization dynamics of the SNARE protein PEN1 and the atypical myrosinase PEN2. PEN1 is a plasma-membrane localized syntaxin that is subject to pathogeninduced cell polarization and required for focal secretion at sites of attempted fungal invasion. PEN2 represents a component of a distinct secretion pathway and is required for local activation of toxic secondary metabolites at fungal interaction sites. Our research aims at identifying intrinsic protein features that govern PEN protein subcellular behavior and protein functionality within plant innate immunity. Nucleocytoplasmic signaling in plant-microbe interactions: A major focus of this research project is to analyze molecular mechanisms that regulate spatial communication between the cytoplasm and the nucleus in plant cellular immunity to pathogenic microbes. On the host side, we study the functions of nuclear transport receptors and nuclear pore complex proteins (nucleoporins) that are essential for plant disease resistance and control nucleocytoplasmic trafficking of proteins and RNAs. Our research on the pathogen side aims at exploring molecular functions of secreted effector proteins that are targeted into host cell nuclei during infection to interfere with plant defense and allow host invasion. Pathogen induced differentiation and plant hormone crosstalk: Focus of the project is investigation of the fungal pathogen Verticillium longisporum causing vascular disease in members of the family Brassicaceae. Mechanisms of Verticillium triggered transdifferentiation of mesophyll cells to xylem elements are studied with emphasis on key transcription factors. In addition, the role of changes in plant hormone homeostasis and signaling during establishment of Verticillium infection are characterized. Another aim is analysis of crosstalk between gibberellic acid (GA) signal transduction and auxin transport. Auxin and gibberellic acid functionally overlap in their effects on shoot and root growth. It was proposed that these two hormones interact to regulate common targets. The impact of GA on polar auxin transport and GA effects on PIN protein amount and localization are studied. Mutants defective in expression or function of DELLA repressors are analysed to obtain hints on the cross-talk between GA signal transduction, auxin signalling and transport.
Publications
- Live and let die - Arabidopsis nonhost resistance to powdery mildews. European Journal of Cell Biology (2010) 89: 194-199
Lipka, U., Fuchs, R., Kuhns, C., Petutschnig, E. und Lipka, V.
- Mechanisms of functional specificity among plasma-membrane syntaxins in Arabidopsis. Traffic (2011) 12(9):1269-80
Reichardt I., Slane D., El Kasmi F., Knöll C., Fuchs R., Mayer U., Lipka V., Jürgens G.
