Nölke T Schwan C Lehmann F Østevold K Pertz O Aktories K 2016 Hypervirulent Clostridium difficile strains, which are associated with increased morbidity and mortality, produce the actin-ADP ribosylating toxin Clostridium difficile transferase (CDT). CDT depolymerizes actin, causes formation of microtubule-based protrusions, and increases pathogen adherence. Here, we show that septins (SEPT) are essential for CDT-induced protrusion formation. SEPT2, -6, -7, and -9 accumulate at predetermined protrusion sites and form collar-like structures at the base of protrusions. The septin inhibitor forchlorfenuron or knockdown of septins inhibits protrusion formation. At protrusion sites, septins colocalize with the GTPase Cdc42 (cell division control protein 42) and its effector Borg (binder of Rho GTPases), which act as up-stream regulators of septin polymerization. Precipitation and surface plasmon resonance studies revealed high-affinity binding of septins to the microtubule plus-end tracking protein EB1, thereby guiding incoming microtubules. The data suggest that CDT usurps conserved regulatory principles involved in microtubule-membrane interaction, depending on septins, Cdc42, Borgs, and restructuring of the actin cytoskeleton. application/pdf https://sonar.ch/global/documents/278528 eng info:eu-repo/semantics/altIdentifier/doi/10.1073/pnas.1522717113 info:eu-repo/semantics/altIdentifier/pmid/27339141 info:eu-repo/semantics/openAccess Proceedings of the National Academy of Sciences of the United States of America. - 2016 Clostridium difficile actin bacterial toxin microtubules septins Animals Bacterial Toxins Caco-2 Cells Clostridium difficile Dogs GTP-Binding Protein Regulators HeLa Cells Humans Madin Darby Canine Kidney Cells Mice, Inbred C57BL Microtubules Septins Transferases cdc42 GTP-Binding Protein Septins guide microtubule protrusions induced by actin-depolymerizing toxins like Clostridium difficile transferase (CDT). http://purl.org/coar/resource_type/c_6501