The rapidly growing elderly population and the increasing occurrence of memory disorders make the promotion of “healthy ageing” and the treatment of these disorders a major challenge in our modern societies. However, the development of treatments is hindered mainly because the biological basis of memory is still unclear. For this reason a better understanding of the mechanisms regulating memory processes appears fundamental. Normal development of hippocampal networks is crucial for memory and learning. In particular, the proper development of the dendritic arbor and spines is critical for the establishment and function of synapses, and, in turn, for neuronal activity and brain function.In the project presented here, I propose to study the role of Rnd proteins in the regulation of dendrite, spine and synapse formation in the developing hippocampus and their implication in hippocampal-dependent memory. Indeed, my preliminary data and data from the literature indicate that these atypical RhoGTPases are particularly good candidates to modulate these functions but this has not been explored yet. The ultimate goals of this study are to provide mechanistic insights into the critical aspect of memory regulation and eventually to propose new therapeutic strategies for learning and memory disorders. The attractiveness of this project is to study the role of these Rnd proteins directly in vivo by using not only in vivo electroporation of Rnd shRNA but also Rnd conditional knockouts. To successfully achieve the goals of my proposal, I have chosen to conduct this project in a host laboratory which is well known for its expertise in memory, behavior and adult hippocampal neurogenesis. Thus, the successful funding of this proposal will allow me to complement my current experimental and theoretical background especially in the field of neurogenesis and neuronal development but also to investigate new fields of research like memory thereby contributing to my career development.