RHO-DEPENDENT MEMBRANE FOLDING CAUSES SHIGELLA ENTRY INTO EPITHELIAL-CELLS

The small GTPase rho is functionally involved in the formation of cyto skeletal structures like stress fibers or focal adhesion plaques. Shig ella entry into HeLa cells induces a blossom-like membrane structure a t the bacterial entry site. We show here that this membrane-folding pr ocess is rho-dependent. The three rho isoforms were recruited into bac terial entry sites with differential localization relative to the memb rane structure. A rho-specific inhibitor abolished Shigella-induced me mbrane folding and impaired bacterial entry accordingly. S1-myosin lab eling indicated that rho was involved in Shigella-induced actin polyme rization but not actin nucleation in the bacterial invasion site. This provides a major link in the signalization cascade allowing entry of a bacterial pathogen into a eukaryotic cell.