Profilin and actin localizes to Synaptotagmin-induced filopodia
Anna-Karin Johnsson, Roger Karlsson
Department of Cell Biology, The Wenner-Gren Institute, Stockholm University, S-10691 Stockholm, Sweden.
We are interested in the dynamics of the microfilament system at the leading edge. Our main focus is to explore how profilin:actin is transported to actin polymer forming sites at the inner leaflet of the plasma membrane. As a model system to study this process we are overexpressing synaptotagmin 1 in mammalian cells. This leads to a dramatic change in cell morphology with numerous oversized filopodia beeing formed. In addition to using this effect as a model system we are also interested in characterizing the mechanism responsible for this process. We have seen that the synaptotagmin 1 induced filopodia stain positively for profilin and actin and that they are enriched in the phosphatidylinositol lipid PIP2. Through cotransfection with a dominant negative form of Cdc42 we have indications that the formation of these filopodia is dependent on this small Rho GTPase.
ASCB/ECF-möte i Dijon 27-30 juni 2007