PROJECT PROPOSAL for applicants for Ph.D. fellowships BACKGROUND OF THE STUDY In the nervous system neurons are organized into functional circuits where information

In the nervous system neurons are organized into functional circuits where information between cells is transmitted by axons and dendrites. Axons are slender projections that extend over long distances in order to reach defined targets, i.e. other neurons, muscles or glandular cells. Growth cones, located at the distal tip of axons, play a crucial role in guiding axons to their correct target sites. Growth cones respond to extracellular guidance cues which lead to coordinated changes of cytoskeletal polymers, F-actin and microtubules. Rearrangement of the growth cone cytoskeleton promotes shape changes that ultimately result in growth cone advance. In the last decades a large number of guidance molecules, repellents and attractants, have been identified. In addition to the navigation factors, the related downstream signalization pathways were also described in remarkable details. Surprisingly however, we learnt much less as to how the different guidance systems affect the activity of the cytoskeleton regulatory proteins, and which cytoskeletal effector is regulated by which signaling pathway.