The cytoskeleton of plants has structural function and provides a network of transport and signalling within the cell. Upon fungal infection a profound rearrangement of the actin cytoskeleton takes place. Changes in the cytoskeleton may be part of the pathogen defence systems of plants. The aim of this proposal is to investigate the effect of Verticillium dahliae and Verticillium longisporum infection on the actin cytoskeleton of Arabidopsis thaliana and Brassica napus along with the developmental consequences of such effects. The activity of Verticillium extracts containing putative toxins will be tested in transgenic plants expressing fimbrin-GFP to allow visualisation of the actin cytoskeleton in vivo and real time. Changes in structure and dynamics of the actin cytoskeleton affect endo- and exocytosis and possibly result in changes in the localisation of auxin carriers. As a consequence root growth and development might be disturbed. These processes will be studied using subcellular markers in plants treated with Verticillium extracts. (click here for the german version)