Final Activity Report Summary - CORTACTINNMQ (Cortactin signalling and actin dynamics control in cell migration and bacterial invasion)
On other hand, cortactin and crk were shown to sinergise on actin polymerization during the invasion of Shigella, and that effect was dependent on the tyrosine phosphorylation of cortactin. We analysed if similar model could apply to EPEC infection. Using siRNAi and overexpression of a dominant negative mutant of crk, we demonstrated that Crk is not required for pedestal formation by EPEC. This result establishes a major signal transduction difference between Shigella and EPEC infection models.
We used purified recombinant cortactin and tir proteins to demonstrate a direct interaction of both and to characterise the effect of this interaction on actin polymerisation in vitro. Using nck and n-wasp K.O. cells we further analysed what type of complexes are de facto formed in vivo.